# # Pediatric Critical Care Review Hasan Pappas

1. Nosocomial infections are an unfortunate complication of hospitalization. All of the following statements regarding nosocomial infections in children are true except. A. Hospital acquired infections are generally highest in teaching hospitals B. Surgical services have the highest rate of nosocomial infections C. In the pediatric services, respiratory infection is the most common nosocomial infection D. E. coli is the most common cause of pediatric urinary tract infections E. Klebsiella is the most common cause of lower respiratory infections in newborns Click here for answer 2. Which of the following is least accurate regarding nosocomial upper respiratory infection: A. When patients with nasotracheal tubes in place develop maxillary sinusitis, pneumococcus is the most common organism B. It has been shown that in acute sinusitis, culture of the nose or throat do not yield the organisms responsible for the sinusitis C. Corneal ulcers, if discovered, must be treated aggressively to prevent progression to hypopyon, corneal destruction & perforation. D. Data suggest that there is little overall effect of a different physical plant of the hospital, whether new or old, on the resultant nosocomial infection rate Click here for answer 3. Respiratory borne nosocomial infections are associated with increased morbidity and mortality, which is likely to increase hospital costs. Regarding this topic which of the following statements is not true: A. Patients treated with H2-blockers are at higher risk of tracheal colonization with gram negative bacilli B. Ventilators with humidifying cascades rather than nebulizers have little role in contaminating patients if the tubing is changed every 48 hours C. Aspiration occurs more often in children with an uncuffed endotracheal tube compared to those with a cuffed tube D. Initial colonization begins in the stomach or hypopharynx with subsequent spread to the trachea E. Anaerobes are the dominant organisms that colonize the trachea in intubated patients Click here for answer 4. All of the following statements regarding infections associated with arterial cathererization are true except: A. Insertion by a surgical cutdown is associated with a significantly higher risk of localized and systemic infection compared to percutaneous insertion B. Catheters in place for greater than 4 days have a significantly higher risk of being infected C. Local inflammation correlates well with duration of insertion of the catheter D. Single patient disposable transducers can be used up to 4 days without bacteremia E. Candida albicans and enterococcus are most common organisms involved in infection Click here for answer 5. All of the following statements regarding central venous catheterization are true except: A. Catheters placed during an active infection may become colonized with the same organism causing the bacteremia B. The proximity of a tracheostomy tube may be a relative contraindication for a subclavian catheter placement C. Pulmonary artery catheters have a significantly higher incidence of positive catheter tip cultures after 72 hours of insertion D. Staphylococcus epidermidis and staphylococcus aureus are the most commons causes of parenteral nutrition associated infections E. Fifty percent of parenteral nutrition associated infections are fungal Click here for answer 6. Select whether the following statements regarding nosocomial infections in children are true or false: ____ Skin site erythema greater than 4 mm in diameter, fever and positive skin cultures are predictive of catheter-associated infection ____ Asymptomatic Pseudomonas bacteremia in dialysis patients has been reported ____ External shunts for hemodialysis are most commonly infected by Staphylococcus aureus ____ Approximately 10 % of cannulas placed for extracorporeal life support become infected ____ Coagulase-negative staphylococci are the most common cause of catheter-related sepsis Click here for answer 7. All of the following statements regarding urinary tract infection in children are true except: A. In the newborn period males outnumber females 3:1 to 6:1 B. In B. In the Pediatric ICU, the cumulative risk of urinary tract infection in catheterized patients approaches 30% C. In a midstream “clean catch” specimen, greater than 105 organisms/ml indicates infection D. Meatal cleansing with providone-iodine and use of impregnated catheters significantly decreases the incidence of urinary tract infection E. Urinary catheters are more likely to be colonized with gram positive than gram negative bacteria Click here for answer 8. All of the following statements regarding intracranial pressure devices are true except: A. Increasing frequency of breaks in the system increases the risk of infection B. Prophylactic antibiotic coverage significantly decreases the incidence of infection C. Duration of placement is directly related to infection rates D. Placement either in the intensive care unit or in the operating room appears to have no relationship to the rate of infection E. Intraventricular hemorrhage in the presence of an intracranial pressure greater than 20 cm H20 increases the rate of infection Click here for answer 9. All of the following statements regarding childhood infections are true except: A. Common offending organisms during the first seven days of the life are Group B streotococci, E.coli,and Listeria monocytogenes B. Ampicillin and a third generation cephalosporin will effectively cover the organisms in Answer A C. H. infuenzae, S. pneumoniae and N. meningitidis are the three most common causes of bacterial meningitis and pneumonia in children D. In the septic child with an abdominal focus, ampicillin, gentamicin and tobramycin are adequate E. Avoiding monotherapy with cephalosporin in the treatment of catheter sepsis decreases the risks of emerging resistant organisms Click here for answer 10. Match the clinical features with the corresponding type of Group B-streptococcal infection: A. Early onset neonatal Group-B Streptococcal infection B. Late onset Group-B Streptococcal infection ____ 1. Higher association with pneumonia ____ 2. Higher association with meningitis ____ 3. Type III isolated 95% of the time ____ 4. Poor correlation with maternal Click here for answer 11. Both the choice of antibiotics and the population at risk being treated affect bacterial complications of a disease. Select whether the following statements are true or false: ____ Ampicillin/gentamicin is a synergistic combination against Group B Streptococcal infection ____ Ampicillin/chloramphenicol is a synergistic combination against Group-B Streptococcal infection ____ Low complement levels, poor opsonization capacity, and decreased immunoglobulin levels account for a newborn’s susceptibility to Group-B Streptococcal infection ____ Simple and exchange transfusions improve short-term outcome in Group-B Streptococcal infection ____ Most babies with Group-B Streptococcal infection are born to mothers who possess antibodies against the infecting strain ____ Listeria monocytogenes becomes more coccoid in morphology the longer it stays in culture ____ High risk groups for Listeria monocytogenes include neonates, pregnant women, and the elderly ____ Listeria monocytogenes has a bi-modal presentation similar to Group-B Streptococcal infection Click here for answer 12. Regarding sepsis, match the following associated findings with the most accurate diagnosis A or B: A. Early onset Listeria monocytogenes sepsis B. Late onset Listeria monocytogenes sepsis ____ 1. Mother has a “flu-like” illness ____ 2. Meningitis ____ 3. Type 4B ____ 4. Mothers are asymptomatic Click here for answer 13. A full-term infant is born by spontaneous vaginal delivery to a mother with active herpetic lesions. All of the following statements regarding Herpes Simplex virus infection are true except: A. Contraction during delivery is the most common B. Approximately 6% of babies delivered by Cesarean section within 4 hours of rupture of Membranes become infected C. 10-20% of adult genital diseases may be caused by Type I Herpes Simplex virus D. Incubation period is approximately 2 days E. Premature babies are more likely to be affected Click here for answer 14. Select whether the following statements regarding Herpes Simplex virus are true or false: ____ Mucosal or skin lesions are only present 20-30% of the time in neonatal diagnoses ____ Meningoencephalitis occurs in 75% of neonatal diagnoses ____ Disseminated diagnosis has a mortality rate of 40% ____ Type 2 has an increased rate of pneumonitis and disseminated intravascular coagulopathy than Type 1 ____ Mothers with genital lesions need to beisolated from their babies ____ It may be wise to isolate the mother from the newborn when the mother has oral lesions Click here for answer 15. A 2 year-old male presents to the emergency department with tachycardia, hypotension, fever, and ecchymotic lesions on his trunk and lower extremities. You suspect meningococcemia. All of the following statements regarding Neisseria meningitis are true except. A. The disease caused by Neisseria meningitidis is usually endemic B. Ninety percent (90%) of infections occur in children < 2 years of age C. Prior infection with influenza A or B has been associated with increased susceptibility to infection with Neisseria meningitidis D. More common in males E. Carriage of the organism in the nasopharynx is very rare Click here for answer 16. Unfavorable prognostic features in meningococcal infection include all of the following except: A. Cerebrospinal fluid, white blood cell count of 3 mononuclear cells/mm3 B. Presence of petechiae for < 12 hours prior to admission C. Presence of shock D. An erythrocyte sedimentation rate of 100 mm/hr E. A peripheral white blood cell count of 3000/mm³ Click here for answer 17. Which of the following is true regarding fulminant meningococcemia: A. Rarely fatal B. Petechiae are universally absent C. Large doses of exogenous corticosteriods always reverses the shock state D. Cardiovascular collapse is secondary to endotoxemia E. Mortality is approximately 35% in patients with unfavorable pronostic factors Click here for answer 18. Which statement is true regarding meningococcal infection: A. High dose methyprednisolone always reverses the associated shock state B. Myocarditis develops 24-48 hours after presentation in 3-5% of all patients C. Pneumonia is always mild D. Rifampin prophylaxis of household and day care center contacts is recommended Click here for answer 19. Which of the following infections is associated with petechiae: A. H. influenza B. N. gonorrhea C. N. meningitidis D. S. pneumoniae E. All of the above Click here for answer 20. Which of the following statements regarding H. influenzae type b infection is least accurate: A. Acute sepsis may mimic meningococcemia B. Adrenal hemorrhage is recognized in fatal cases C. Death related to overwhelming sepsis is caused by intractable hypotension and cardiac dysfunction D. Chemoprophylaxis with Rifampin is recommended for all household contacts E. Rifampin prophylaxis should be administered one month after completion of the therapeutic antibiotic course Click here for answer 21. Which of the following statements regarding meningitis in children is true: A. Otitis media has not been associated with H. influenzae meningitis B. Contaminated lake water is a recognized source of Neigleria meningitis C. Meningitis usually involves the parenchyma of the brain D. Virchow-Robin spaces are continous extensions of the subararchnoid space which prevent bacteria from infecting the surface of the brain E. The process of meningitis rarely includes cerebral edema Click here for answer 22. Regarding the pathophysiology of meningitis, which of the following statements is/are the most appropriate responses (s): A. Convulsions in the first 72 hours of the illness carry a grave prognosis B. Children less than 5 years of age who attend a day care center are a lower risk of meningitis than the average child C. Limitation of ocular movement always indicates increased intracranial pressure D. Papilledema that develops within the first day of presentation is more likely to be due to a ruptured brain abscess than meningitis itself E. All of the above Click here for answer 23. Which one of the following statements is incorrect regarding the clinical manifestations of bacterial meningitis: A. Convulsions occur in 30% of cases during the course of the illness B. Convulsions that are limited to the first 48-72 hours of illness carry a better prognosis C. Kernig’s sign is positive when pain is elicited after extension of the leg D. Limitations of extraocular movements are secondary to paresis of cranial nerve VII E. Tuberculosis and crypotococcal meningitis are more likely to present with focal signs and papilledema Click here for answer 24. All of the following statements regarding laboratory diagnosis of meningitis are true except: A. Definitive diagnosis is made by cerebrospinal fluid culture B. The normal opening pressure, by spinal manometer, in the neonate is 90-110 cm H2O C. The normal opening pressure of older children and adults is up to 180 cm H2O D. An acceptable upper limit for white blood cell numbers of cerebrospinal fluid in the full-term infant, is 32 white blood cells/mm³ E. In newborns, neutrophils may comprise 90% of the white blood cells in the cerebrospinal fluid and still be considered normal Click here for answer 25. Cerebrospinal fluid abnormalities can help to determine the etiology of meningitis. Select whether the following statements are true or false: ____ Spinal fluid remains clear with up to 500 white blood cells/mm³ ____ Red blood cells in the cerebrospinal fluid may raise the protein by 5 mg/100ml for every 1000 red blood cells/mm³ ____ Abnormal cerebrospinal fluid lactate is > 2mg/100ml Click here for answer 26. Which of the following is true regarding partially treated meningitis: A. Clinical course and outcome are improved when prior treatment (oral antibiotics) has been administered prior to hospitalization B. Cerebrospinal fluid becomes “sterile” within 1 hour of parenteral antibiotic administration C. Specific antigens of the bacterial capsule are detectable for up to two weeks after antibiotic therapy D. Approximately 50% of children receive antibiotics in some form prior to diagnosis Click here for answer 27. Regarding evaluation and therapy of a child with meningitis, which of the following statements is least accurate: A. Tuberculous meningitis is less likely to present with focal signs and papilledema than other causes of bacterial meningitis B. Cryptococcal meningitis is more likely to present with focal signs and papilledema than bacterial meningitis C. The presence of retinal hemorrhages suggests cortical vein thrombosis D. The normal cerebrospinal fluid opening pressure in the neonate is 100 mm H2O Click here for answer 28. The following statements regarding complications of meningitis are all true except: A. SIADH has been noted in > 50% of patients B. Subdural effusions mostly occur beyond the first week of the illness and eventually resolve spontaneously C. Cerebral vasculitis leading to capillary leakage is the likely pathogenesis of subdural effusions D. The most common cause of recurrent fever after initial treatment of meningitis is a nosocomial infection E. By day 5 of treatment, only 30% of children with H. influenzae meningitis will be afebrile Click here for answer 29. Select whether the following statements regarding childhood meningitis are true or false: ____ Fever that persists beyond the 10th hospital day is most likely due to subdural effusions, drug fever, arthritis, brain abscess and nosocomial infection (in descending order) ____ Thirty to fifty percent (30% to 50%) of persistent fevers have an unknown etiology despite adequate treatment for meningitis with negative blood cultures ____ The outcome of children is directly proportional to the persistence of positive cerebrospinal fluid cultures ____ Gram negative endotoxin may be related to the formation of intracranial abscesses, hydrocephalus and porencephalic cysts in children with gram negative meningitis Click here for answer 30. All of the following statements regarding therapy of meningitis are true except: A. Respiratory isolation is required for 24-48 hours after initiation of antibiotic treatment B. Hyperglycemia may worsen outcome of children with cerebral ischemia C. The American Academy of Pediatrics recommends dexamethasone as a treatment option for children with suspected bacterial meningitis D. Aztreonam, a synthetic monocyclic b-lactam antibiotic, has been shown to be effective in the therapy of gram negative infections E. The child with a ventriculoperitoneal shunt and suspected meningitis should receive a combination of ampicillin and clindamycin for adequate antimicrobial coverage Click here for answer 31. Select whether the following statements regarding childhood meningitis are true or false: ____ Most neonatal meningitis cases require ³ 21 days of intravenous antibiotics ____ With tuberculous meningitis, a lymphocytic reaction in the cerbrospinal fluid may mimic a viral etiology ____ In the first several weeks of tuberculous meningitis, cerebrospinal fluid glucose and protein may remain normal ____ Acid-fast smear in tuberculous meningitis is positive in > 90% of patients ____ Long-term sequelae for bacterial meningitis occur in 30-50% of affected patients Click here for answer 32. Singer criteria for hospital admission of patients with probable aseptic meningitis include all of the following except: A. Deteriorating clinical condition B. Patients < 1year of age C. All children who have received antibiotics in the week prior to presentation D. Cerebrospinal fluid: increased protein, decreased glucose, > 1000 WBC/mm³ E. An older sibling with an upper respiratory infection Click here for answer 33. The following statements are all true regarding ECHO and coxsackie viruses except: A. Typical incubation period is 3-5 days B. Group B is most common Coxsackie, and type 9 among ECHO viruses C. Peak incidence occurs in late summer D. Meningitis is usually benign E. Incidence rates increase with higher socio-economic groups Click here for answer 34. Select whether the following statements regarding meningitis are true or false: ____ Lymphocytic choriomeningitis develops after contact with infected rodents ____ Corticosteriods greatly enhance recovery time of aseptic meningitis 35. All of the following statements regarding viral encephalitis are true except: A. Enteroviruses and Arboviruses are the most common etiologic agents B. In 75% of cases, no specific etiology can be established C. The hallmark of the disease is a disturbed higher cerebral function D. The majority of cases are secondary to hematogenenous spread E. With Herpes Simplex virus, the EEG displays abnormalities in the occipital cortex Click here for answer 36. Which of the following statements is true regarding arboviruses: A. Highest mortality occurs with California equine encephalitis B. Transmitted by rodents C. Occurs in late autumn and early winter D. St. Louis encephalitis is the most common arbovirus infection in the US Click here for answer 37. Match each of the following arboviruses with its likely clinical presentation: A. Eastern Equine Encephalitis B. Californian Equine Encephalitis C. Western Equine Encephalitis D. Venezuelan Equine Encephalitis ____ Midwest: “LaCrosse strain”; school-age children; most recover without sequelae ____ Abrupt onset: children, 1 year of age; extensive neuronal death with devastating sequelae ____ California and Texas; hyperplasia and occlusion of small blood vessels; elevation of intracranial pressure ____ Affects adults more than children; rare neurologic involvement Click here for answer 38. All of the following statements regarding Rocky Mountain Spotted Fever are true except: A. It is a tick borne disease B. Occurs primarily in the Rocky Mountain area C. Complicated by meningoencephalitis in 30% of cases D. Ten percent (10%) of cases progress to coma Click here for answer 39. A 6-year-old female presents with a high temperature for 3 days despite negative blood and cerbrospinal fluid cultures. A CT scan of the brain reveals a 2 cm ring-enhanced lesion consistent with a brain abscess. The most likely predisposing condition is: A. Suppurative otitis media B. Suppurative mastoiditis C. Suppurative frontal sinusitis D. An uncorrected Tetralogy of Fallot Click here for answer 40. Which of the following statements about brain abscess is most accurate: A. Abscess formation occurs in areas of the brain with generous blood supply and is therefore most commonly seen in gray matter B. Brain abscess formation very commonly complicates bacterial meningitis beyond the neonatal period C. When seizures develop, they are always focal in type D. Brain abscess formed by hematogenous seeding is usually in the distribution of the middle cerebral artery E. All of the above Click here for answer 41. Regarding the microbiology and chemotherapeutic treatment strategies for brain abscess, which of the following is most accurate: A. The overwhelming majority of brain abscesses are caused by a single organism and polymicrobial etiology is very rare B. Suppurative otitis media due to H. influenza type b is the most common predisposing factor C. Aminglycosides are the drugs of first choice D. In the neonatal period, Citrobacter diversus and Proteus mirabilis are the most common etiologic agents E. All of the above Click here for answer 42. Which of the following statements regarding subdural empyema is true: A. The subdural space at the base of the brain is most frequently involved B. Is usually restricted from spreading by the suture lines where the dura is firmly adherent C. H. influenzae is the most common etiologic agent in infants D. MRI is the diagnostic imaging procedure of choice E. All of the above Click here for answer 43. Match the most likely organism with its disease process: A. Brain abscess in a child with a cyanotic congenital heart disease B. Subdural empyema C. Spinal epidural abscess ____ 1. Staphylococcus aureus ____ 2. Aerobic streptococci ____ 3. Hemolytic streptococci Click here for answer 44. Which is the following is not a prosposed diagnostic criterion for Toxic Shock Syndrome in children: A. Fever > 39° C. B. Diffuse or palmar erythema C. Hypotension D. Lymphocytosis E. Diarrhea or vomiting Click here for answer 45. Which of the following is true regarding Toxic Shock Syndrome: A. Is caused by coagulase negative staphylococci B. Neutralizing antibodies are formed immediately by the body against the toxin C. Menstrual cases seen exclusively in African-American D. A serum creatinine > 3mg/dl at presentation predicts a prolonged hospital course E. All of the above Click here for answer 46. Which of the following statements regarding Rocky Mountain Spotted Fever is true: A. Most victims are adults B. Dermacentor variabilis is most common tick involved in the eastern regions of the US, and D. Andersoni is the most common tick in the West C. Peaks in winter D. Incubation period is 24 hours E. Man is the primary host of R. Ricketsii Click here for answer 47. All of the following statements are true regarding Rocky Mountain Spotted Fever except: A. Initial presentation consists of fever, headache, and malaise B. Rash appears 10 days after the onset of fever and begins on the trunk C. Erythematous macules become petechial over the course of several days D. Complement fixation or indirect fluorescent antibody titers are used to confirm the diagnosis E. Diffuse vasculitis affects many organ systems Click here for answer 48. All of the following statements regarding Legionnaire’s disease are true except: A. Mostly affects adult males B. May present with cerebellar ataxia C. Lung disease is lobar D. Fever, non-prodcutive cough, hematuria and encephalopathy are presenting signs E. Accounts for 50% of pneumonias in adults Click here for answer 49. Superantigens are potentially involved in which of the following disorders: A. Toxic Shock Syndrome B. HIV infection C. Kawasaki Syndrome D. All of the above E. None of the above Click here for answer 50. Toxic Shock Syndrome in: A. An adult B. A child ____ 1. Prodromal synptoms of fever, mucosal erythema, vomiting, dizziness almost always seen ____ 2. Hypotensions is prominent at admission Click here for answer 51. Match the following: A. Brain abscess in a newborn with meningitis B. Brain abscess in a child with uncorrected Tetralogy of Fallot C. Brain abscess secondary to a penetrating brain injury D. Brain abscess in a patient with a compromised immune system ____ Nocardia spp. ____ Citrobacter diversus ____ a-hemolytic streptococci ____ Staphylococcus aureus Click here for answer Answers 1. E In pediatric and newborn services, lower respiratory infections are the most common type of nosocomial infection followed by bacteremia, urinary tract, cutaneous and surgical wound infection. S. aureus predominates as the most common cause of lower respiratory infections in newborns, not Klebsiella. Klebsiella is the most common organism isolated from pediatric lower respiratory tract nosocomial infections. Other common lower respiratory pathogens include P. aeroginosa, Coagulase Negative staph, and E. coli. E. coli is the most common cause of pediatric, nosocomial, urinary tract infections. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 976, 997 table 30.2) 2. A Pneumococcus and Branhamella are the most common organisms causing sinusitis in the general pediatric population < 10 years of age. In ICU patients with a nasotracheal tube in place, a variety of gram-negative organisms, including, P. aeruginosa, Klebsiella, Proteus, E. coli, Enterobacter and Serratia, are found. Often, these infections are polymicrobial. Direct aspiration and culture of the material should direct therapy. Ocular infections are often caused by P. aeruginosa and may progress if left untreated. Infection from environmental contaminants also occurs. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 987-988) 3. E Gram negative organisms, not anaerobes, are the dominant organisms that colonize the trachea in patients who are intubated. Colonization is increased in those patients receiving cimetidine or antacids. Respiratory equipment, including nebulizers, medications and hand ventilators may also become contaminated and contribute to respiratory infections. Uncuffed endotracheal tubes contribute to the aspiration of oral secretions. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 989) 4. C Local inflammation does not correlate with the duration of arterial catheter insertion and is not predictive of catheter tip colonization. All other responses are true. Catheters placed by surgical cutdown have twice the incidence of infection and nine-fold increase in septicemia. Disposable transducers used for 4 days had no higher risk of infection than those used for 2 days. At 8 days, the prevalence of contamination was significantly higher for the transducers (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 981-982) 5. E Approximately 30% of TPN infections are caused by fungi with C. albicans, candida species, and Torulopsis being primarily responsible. All of the other statements are true. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 984) 6. T, T, T, F, T In spite of the inherently invasive nature of ECMO, few reports of infectious complications have risen. Approximately 5% of the cannulas placed for extra-corporeal life support became infected. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 986-987) 7. D Cleansing with providone-iodine or the use of antibiotic impregnated catheters have not been shown to significantly lower the incidence of urinary tract infections in the intensive care unit. Gram positive isolates predominate in UTI in both sexes. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 991-992) 8. B The prophylactic use of antibiotics does not significantly decrease the incidence of infection associated with intracranial pressure monitoring devices, and therefore, use of prophylactic antibiotics in this setting is not indicated. Increasing the frequency of breaks into the system, such as obtaining samples or flushing the catheter with saline, does increase the risk of infection. However, placement of these catheters either in the intensive care unit or the operating room, has not been shown to make a substantial difference in terms of the rate of infection. The presence of blood within the ventricular system does increase the risk of infection. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 993-994) 9. D Ampicillin and an aminoglycoside alone will not be adequate coverage for intraabdominal infection. It is necessary to cover for anaerobic bacteria as well. Therefore, a combination of ampicillin, gentamycin and clindamycin, is one approach the child with abdominal sepsis. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1012-1013) 10. A, B, B, B Early onset neonatal group B streptococcal infections are usually seen within the first week of birth. Early onset disease is primarily a disease of premature infants < 35 weeks gestation and weighing <2500 g at birth. Late onset infection can be delayed up to three months after birth. There is a poor correlation between the late onset group B streptococcal infection and maternal colonization, 95% of the isolates are Type III, and there is a higher association with meningitis, as opposed to association with pneumonia that is seen with early onset group B streptococcal infection. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1016-1017) 11. T, F, T, T, F, T, T, T The initial antibiotic therapy of the sick neonate generally consists of ampicillin and an aminoglycoside. While the combination of ampicillin and gentamicin is synergistic against group B streptococcal infection, the addition of chloramphenicol to ampicillin is of no additional benefit. The immaturity of immunologic system of the newborn predisposes this group of patients to susceptibility to group B streptococcal infection. It is the deficiency in complement, antibodies and plasma components that is thought to be responsible for the short-term outcome improvement in simple and double volume exchange transfusions. Listeria monocytogenes generally affects extremes of age and pregnant women, and it has a bi-modal presentation similar to group B streptococcal infection (i.e., early onset and late onset). (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1019-1020) 12. A, B, B, B Late onset Listeria monocytogenes infection is usually seen in healthy full-term infants who are born to mothers who are asymptomatic at the time. The vast majority of infections are due to Type 4 B and there is a higher association with meningitis. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1020-1022) 13. D The majority of infections in which a source is identified are related to maternal genital infections. The incubation period for neonatal Herpes is usually longer than seven days. The likelihood of the neonate contracting the disease is correlated with a prolonged rupture of membranes (> than 6 hours) in a mother with active genital infection. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1023-1024) 14. T, F, F, T, F, T Herpetic meningoencephalitis occurs in approximately 50% of neonatal diagnoses. Mothers with genital lesions need not be isolated from their babies, in contrast to mothers with oral or perioral lesions who should be preferably isolated from their newborn babies. The prognosis for babies with disseminated infection is approximately 90%. HSV-2 has an increased rate of pneumonitis and DIC, which may relate to its poorer outcome when compared to HSV-1. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1023-1024) 15. E Neisseria meningitidis is usually endemic and is commonly carried in the nasopharynx of the healthy population. The infection is more commonly in males. Influenza A and B are associated with an increased susceptibility to infection. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1025-1027) 16. D Several attempts at classifying meningococcal disease severity and prognosis have occurred. The characteristics that are associated with a worsened outcome represent failure of the child’s organ systems to adequately compensate for the disease. A low leucocyte count in the periphery or in the CSF may represent a failure of the host’s neutrophils to mount an adequate response. Similarly the presence of shock, petechiae, and thrombocytopenia, are unfavorable. The elevation of the sedimentation rate is, in part, due to elevation of the acute phase reactants, which includes fibrinogen, and this will take at least 24 hours. A sedimentation rate of 100mm/hr (as stated in the question) would suggest that the infection has been going on for more than several hours, and it would constitute a good prognostic feature. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1026-1027, Tables 31.13, 31.14, 31.15, 31.16, and 31.17) 17. D The cardiovascular collapse and instability associated with meningococcal infection was originally thought to be due primarily to adrenal dysfunction. However large doses of exogenous corticosteroids were not always effective in reversing the shock state, and therefore, the more recent prevailing theory is that the cardiovascular collapse is actually secondary to endotoxemia with its effect in inducing multiple organ dysfunction syndrome. Fulminant menigococcemia has an estimated mortality rate of 85%. Petechiae are frequently present in this disease and are related to a failure of the hematopoietic system and DIC. Corticosteroids were a promising intervention that have not been demonstrated to universally reverse the shock state. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1026-1029) 18. D Myocarditis which is believed to be a form of vasculitis generally develops a 4-7days after onset of infection, and pneumonia can be very severe and require mechanical ventilatory support. The recommendation of using Rifampin prophylaxis for household and day-care contacts is universally agreed upon. Corticosteroids were a promising intervention that have not been demonstrated to universally reverse the shock state. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp1029-1032) 19. E Petechiae and ecchymosis may be noted with any of the infections mentioned although they are typically associated with Neiseria infection. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1032-1034) 20. E H. influenzae infection may mimic meningococcemia. Adrenal hemorrhage has been noted in 55% of the fatal cases of Hemophilus influenzae sepsis. Intractable hypotension and cardiac dysfunction usually lead to death in affected patients. Rifampin prophylaxis should be initiated immediately after diagnosis of the H. influenzae type B infection, in household contacts. It should be incorporated into the therapeutic antibiotic regimen of the index case in the last few days of therapy, and should not be delayed until one month after completion of antibiotic therapy. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1032-1034) 21. B A history of freshwater lake swimming is an important etiologic risk factor for Neigleria meningitis. Otitis media is often seen in association with H. influenzae meningitis. Meningitis in the vast majority of cases does not actually involve the parenchyma. It is limited to the three layers of the meninges. The Virchow-Robin spaces are a continuous extension of the subarachnoid space, which will allow the bacteria to gain access into the subarachnoid space, and maybe to the most superficial surface of the brain. Meningitis, when severe, is often associated with cerebral edema. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1040-1060) 22. D Even in the absence of an index case within the day care setting, children who attend day care centers are at higher risk of developing meningitis. Convulsions occurring within the first 24-72 hours of meningitis may represent febrile seizures and therefore have a better prognosis. Convulsions that develop beyond this period carry a less favorable prognosis. Limitation of ocular movement may be due to abnormalities in the 3rd cranial nerves and does not always indicate increased intracranial pressure. When papilledema is noted on the first day of admission of meningitis, other etiologies should be sought, particularly an intracranial mass lesion, such as a brain abscess. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1047-1060) 23. D Limitation of ocular movements may result from irritation of cranial nerves III, IV, or VI. Convulsions do occur in at least 30% of meningitis cases. Those convulsions that are limited to the first 24-72 hours carry a better prognosis. See response to question 22 above. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1047-1049) 24. E Bacterial culture of the CSF is considered the gold standard. The presence of any neutrophils in the cerebrospinal fluid in the newborn period should be treated with a high degree of suspicion. This may be one of the early manifestations of meningitis. However, in newborn infants polymorphonuclear leukocytes may comprise up to 60% of the total CSF white cell population and still be considered normal. The opening pressure in the neonate is between 90 and 110 mm H2O, whereas in the older child and adult it may be as high as 180 mm H2O. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1049-1051, Table 32.4) 25. T, F, F Spinal fluid remains clear with up to 500 WBCs/mm3. Erythrocytes raise the CSF protein concentration by about 15mg/dl for every 1000 RBCs/mm3. A cerebrospinal fluid lactate level of more than 14 mg % is considered abnormal. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1049-1047) 26. D Children who are diagnosed and admitted to the hospital for meningitis have commonly received some form of antibiotic, usually oral, prior to presentation. This form of antibiotic usually is not sufficient to treat meningitis, and therefore, it does not improve the outcome in these patients. Several hours after the administration of an appropriate antibiotic, it is certainly possible to inhibit bacterial growth in the spinal fluid. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1051-1052) 27. A Tuberculous meningitis, which is usually a basal form of meningitis, is more likely to present with focal neurologic signs and papilledema, particularly cranial nerve palsies such as cranial nerves VII, VIII and IX. Cryptococcal meningitis may present only with behavioral changes , or it may present with symptoms of a space occupying lesion. The opening pressure in neonates may be as high as 110 mm H2O. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1052-1060; American Academy of Pediatrics. Cryptococcus neoformans infections. In: Pickering LK, ed. 2000 Red Book: Report of the Committee on Infectious Diseases. 25th Ed. Elk Grove Village, Il) 28. E By day 5 of treatment with antibiotics, 85% of children with H. influenzae meningitis will be afebrile. The syndrome of inappropriate anti-diuretic hormone secretion (SIADH) has been noted in more than 50% of patients with meningitis. Under these circumstances, restriction of fluid and close monitoring of fluids and electrolytes are a necessary part of the management of these patients. Subdural effusions which are a recognized complication of meningitis, generally resolve spontaneously and do not require surgical intervention in the vast majority of cases. Nosocomial infection is a common cause of recurrent treatment after initial treatment for meningitis. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1052-1054) 29. T, T, F, T The causes of fever that persists beyond the 10th day in the setting of meningitis are subdural effusions, drug fever, arthritis, brain abscess and nosocomial infection. Thirty to fifty percent of fevers are idiopathic. Persistence of a positive cerebrospinal fluid culture would be a poor prognostic feature in patients with bacterial meningitis. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp1053-1060) 30. E The frequency of shunt infections varies between 2 and 30% and is influenced by a variety of factors. Children suspected of having a shunt infection or meningitis should receive coverage with antibiotics for gram positive organisms including staphylococcus species as well as gram-negative organisms. Staphylococcal species are the most common. Initial therapy should include vancomycin because the frequency of methicillin resistant staphylococci is high. Respiratory isolation of the patient for the initial 24hours of antimicrobial therapy is an important epidemiologic consideration. The data regarding the use of dexamethasone in meningitis are controversial. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1061-1062) 31. T, T, F, F, T The CSF cytology in tuberculous meningitis mimics the lymphocyte predominance found in viral meningitis. CSF glucose is classically reduced and the protein level is elevated. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1050-1061) 32. E Aseptic meningitis is an inflammatory process of the meninges that results from a number of different etiologies. An elevated protein, a pleocytosis and the absence of organisms on gram stain and culture characterize it. The etiologies associated with this diagnosis are rather large and include viral, bacterial, and fungal causes. Admission of the patient to the hospital depends upon the certainty of the diagnosis. To the extent that the patient is stable and the likelihood of a partially treated bacterial etiology is ruled out, outpatient management may be acceptable. (Mandell ML, et al. Principles and Practice of Infectious Diseases, 3rd Edition; pp 1367-1379) 33. E Enteroviral infections are higher in lower socioeconomic groups, have a 3-5 day incubation, and are typically seen in the latter part of the summer. The meningitis associated with these infections usually has a benign course. (American Academy of Pediatrics. Enterovirus infections. In: Pickering LK, ed. 2000 Red Book: Report of the Committee on Infectious Diseases. 25th Ed. Elk Grove Village, Il) 34. T, F (Mandell ML, et al. Principles and Practice of Infectious Diseases, 3rd Edition; pp 1367-1379) 35. E With Herpes Simplex virus infection, particularly with meningoencephalitis, the electroencephalogram displays abnormalities typically in the frontal and temporal lobe area of the brain. All of the other responses are true (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1064-1066) 36. D Arboviruses are arthropod borne viruses and are a common cause of encephalitis. These infections are usually seen in late summer and spring, and they are transmitted by arthropods. St. Louis encephalitis is the most common Arbovirus infection in the US, and is generally a mild disease. The highest mortality usually occurs with Eastern equine encephalitis. California encephalitis is usually a mild disease. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1062-1064) 37. B, A, C, D St. Louis encephalitis virus is distributed throughout most of the United States and causes major epidemics that peak later than other arboviruses. Most infections are asymptomatic, and less than 1% have overt neurologic disease. Western equine encephalitis is the usual cause of arbovirus encephalitis and California encephalitis viruses occur in the central and eastern United States and cause diseases with a fulminant and mild course, respectively. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1063-1065) 38. B Interestingly, in spite of the name, Rocky Mountain Spotted Fever occurs primarily in the eastern US, including the Ohio valley area. The disease is a tick-borne illness. See Question 47 below. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1106-1109) 39. D Over the past 30 years, cyanotic congenital heart disease has replaced suppurative otitis media or mastoiditis and suppurative sinusitis as the most common predisposing factor for brain abscess. This is true for the industrial nation, but even in developing nations, it is the most likely predisposing factor. Overall, a predisposing factor can be determined in approximately 85% of all patients with brain abscess, and therefore, a meticulous evaluation for a predisposing factor is warranted in these patients. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1071-1073) 40. D Brain abscesses formed by hematogenous seeding tend to develop at the junction of gray and white matter and usually in the distribution of the middle cerebral artery; hence the predominant location in the temporal and parietal lobes. Beyond the neonatal period, meningitis is a rare form of brain abscess. Seizures, when they occur, are more typically generalized. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1071-1074) 41. D Normal brain parenchyma is highly resistant to invasion by micro-organisms and therefore, abscess formation seems to occur only in areas of the brain with focal ischemia, necrosis, or marginal perfusion. Poor vascular supply in the white matter or at the junction of the gray and white matter makes these areas the most likely to be affected by brain abscess. With the exception of the neonatal period, abscess infrequently complicates a course of bacterial meningitis. In the neonatal period, meningitis, particularly due to Citrobacter diversus and Proteus mirabilis are the most common etiologic agents which usually cause meningitis and are subsequently complicated by brain abscess. When seizures develop in association with brain abscess, they are most commonly a generalized seizure. In up to 30% of brain abscess cases, the microbiology is polymicrobial, which could be a combination of aerobic and anaerobic organisms. Suppurative complications of otitis media or sinusitis are becoming less and less common as an etiologic agent or predisposing factors for brain abscess. Due to poor penetration into the abscess cavity, aminoglycosides are not effective for treatment of brain abscess. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1073-1075) 42. D Unlike the epidural space, the subdural space is not limited by attachment of the dura to the skull sutures, allowing extension and the spread of the subdural empyema over a wide area of the cerebral hemispheres. The potential subdural space is restricted at the base of the brain and therefore involvement of the base of the brain is rare with subdural abscesses. In infants, subdural empyema generally complicates acute meningitis and therefore, is caused by the organisms commonly implicated in causing meningitis. Because the incidence of H. influenza type b as a cause of meningitis in infants has decreased dramatically in the US, this organism is becoming less and less an etiologic agent for subdural empyema. The MRI is the diagnostic imaging procedure of choice for subdural empyema. Advantages of MRI over CT scan include the lack of bone artifact, the ability to detect the smaller extracranial fluid collection, and improved ability to differentiate extracranial collection of fluid from other differential diagnoses such as cerbritis, cerebral edema, and venous thrombosis. MRI can also detect the density difference from elevated protein concentration and therefore distinguish a subdural abscess from other sterile collections such as subdural effusions. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1071-1077) 43. C, B, A In the child and young adult, the most common organism causing localized para-meningeal infections such as a subdural empyema, are the various aerobic streptococci, such as streptococcus pnemoniae, staphylococci either the epidermidus or the aureus species. a-Hemolytic streptococci are the most frequently isolated organisms from brain abscesses in patients with cyanotic congenital heart disease. Staphylococcus aureus is the usual organism causing spinal epidural abscess and accounts for 80% of cases. See response to Q51 below. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1072-1079) 44. D Proposed and simplified diagnostic criteria for toxic shock syndrome in children include: fever equal to or greater than 39° C, lymphopenia, rash, shock, diarrhea and vomiting, and irritability. CDC has not adopted these simplified criteria, however. Toxic shock syndrome can also be caused by streptococci, and the streptococci toxic shock syndrome is one from of severe Group A streptococcal disease. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1103-1106) 45. D Staphylococcal Toxic Shock Syndrome is caused by a coagulase postive staphylococcus that liberates an exoprotein known as TSST-1. The host does not form neutralizing antibodies to the toxin for at least 2 years after infection. This, in addition to the noninvasiveness of the organism, may help to explain the recurrent nature of disease, especially in menstrual cases. Menstrual cases are seen exclusively in the white Caucasion population. patients who present with elevated serum creatinine, particularly when the serum creatinine is greater than 3 mg/dl tend to have a prolonged hospital course. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1103-1106) 46. B See Response to Question 47 (Rogers MC, et al.Textbook of Pediatric Intensive Care, 3rd Edition; pp 1106-1109) 47. B Rocky Mountain Spotted Fever is caused by R. rickettsii. In the eastern regions of the US, Dermacentor variabilis is the most common tick involved, whereas in the western region, the Dermacentor andersoni is the most common tic involved. The disease is usually prevalent in the summer months, and the highest incidence of disease among children age 5-9 years. More than half of all cases appear in persons younger than 19 years of age. The incubation period is 2-14 days, with an average of 7 days. Man is only incidentally involved when bitten by an adult tick. The initial presentation consists of headaches, malaise, myalgias. The rash generally appears within 2-4 days after the fever, and has been noted in nearly all children with the disease. The eruptions begin as discrete macules, first observed on the ankles and feet, and shortly thereafter on the wrists and hands. Regardless of the progression of the rash, the rash is almost always most pronounced over the extremities and almost always involves the palms of the hands and the soles of the feet. Over a period of several days, the rash becomes petechial and purpuric. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1106-1109) 48. E Legionnaire’s disease was first recognized in 1976 after an outbreak of pneumonia in Philadelphia. The organism, L. pneumophila, accounts for only about 15% of pneumonia in adults, but it causes acute pulmonary disease, mostly among adult males. The disease has also been noted in infants and children and the prevalence of elevated titers in children is quite high in some communities. The presenting complaints are usually fever, non-productive cough, encephalopathy and seizures; cerebeller signs may be markedly severe in these patients. The lung disease is usually lobar in nature, hepatic and renal abnormalities are often also noted. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1109-1110) 49. D Super antigens are antigens that are derived from either bacteria or viruses which interact with the major histocompatibility class II proteins and activate T-cells by binding to the variable region of the beta chain of the T-cell receptor. Stimulation of the T-cell receptors leads to polyclonal T-cell activation which results in release of massive amounts of tumor necrosis factor alpha and interleukin 6. These cytokines are most likely the elements responsible for the shock and multi-organ dysfunction seen in these diseases. Super antigens differ from conventional antigens mainly in the manner in which they are processed and presented to the T-cell receptors. The polyclonal activation generally results in a reduction of the number of circulating CD4+ lymphocytes; however, this reduction is usually reversible and transient. Super antigens are potentially involved in all the three disorders mentioned in the question. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp1103) 50. B, A Some differences have been noted between children and adults with toxic shock syndrome. While only a small percentage of adults have had a prominent prodromal illness, nearly all children have between 1-6 days of symptoms preceding the illness. These symptoms include fever, mucosal hyperemia, erythroderma, vomiting, diarrhea, dizziness, and myalgias. The vast majority of adults admitted to the hospital have hypotension at presentation. This finding is not prominent in children at the time of admission, although it may develop later during the hospitalization. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1103-1106) 51. D, A, B, C Brain abscesses are the most frequently encountered form of localized intracranial infection in children. Death usually occurs with rupture of the abscess and spread of the infection into the ventricular system or herniation secondary to mass effect. Citrobacter and Proteus are the most common etiologic agents in the newborn period. In patients with congenital heart disease, a-hemolytic streptococci are common. Patients who have traumatic injuries are affected by S. aureus. Imunocompromised patient are at risk for Nocardia brain abscesses. (Rogers MC, et al. Textbook of Pediatric Intensive Care, 3rd Edition; pp 1071-1076)