Case 1 2-month-old previously healthy female presents to the ED with a 3-day

history of poor feeding, lethargy, and a weak cry. She has not stooled for 3 days, but normal pattern was every other day. Mother describes her feeding, as licking instead of sucking with poor head control.

The day of admission, she developed a fever to 39°C and became more lethargic.

She was exclusively breast-fed. The family are avid hikers, and the mother is an active gardener.

On examination, the infant is ill-appearing but not distressed. Her vital signs are normal. She has a flat affect, bilateral ptosis, a weak suck, and a weak gag reflex. Her upper extremities are flaccid, and her lower extremities nearly so. She has absent DTR.

Blood glucose is 50 mg/dL. Complete blood count, C-reactive protein, ABG, and head CT are all normal.

Differential Diagnosis

Sepsis: Bacterial;

Streptococcus pnuemoniae, Neisseria meningitidis, Haemophilus influenzae type b, Staphylococcus aureus, Salmonella sp.

Nonbacterial: rare Respiratory syncitial virus, enteroviruses, influenza virus,

adenovirus, herpes simplex virus

Other Metabolic Neurologic: includes infant botulism

Clinical Course

The baby was treated for hypoglycemia, dehydration, and possible sepsis and then transferred to a tertiary care center where the diagnosis of infant botulism was confirmed by stool study. She received BabyBIG and made a full recovery over several months. She never required endotracheal intubation.

Infant Botulism Most common presentation of botulism in the US

Young infants have risk factors for overgrowth Altered flora, pH and motility

Caused by Clostridium botulinum Found in soil and agricultural products 3 forms: infantile, foodborne, and wound Spores in honey have been mplicated, but not spores in light or

dark corn syrup Diagnosis

Culture Toxin in stool Electromyography demonstrates a characteristic pattern

Differential Diagnosis of hypotonia Hypothyroidism: more indolent, no cranial nerve

involvement Myasthenia gravis: earlier in neonatal period:

symptoms wax and waned, weakness not characteristic

Guillan-Barre: rare < 2: presents as ascending paralysis

Polio: usually asymmetric

Question 1 A 3 wk old infant is admitted w/ fever, irritability

and poor feeding. On PE she has temp 38.6oC, weak suck, and poor tone. Her CSF is cloudy w/ a WBC of 250/mm3

What is the most likely etiology of this child’s illness? 1. group B beta-hemolytic Streptococcus 2. Haemophilus influenzae type b 3. Neisseria meningitidis 4. Staphylococcus aureus 5. Streptococcus pneumoniae

Neonatal Sepsis

Pathogens: group B beta-hemolytic Streptococcus Escherichia coli enterococcus Listeria monocytogenes other gram negative enterics

Incidence greatly decreases after 4 weeks 1 mo – 2yrs Streptococcus pneumoniae and

Neisseria meningitiids account for about 75% of cases of meningitis

Neonatal Sepsis

Listeria: In neonates causes sepsis, early (≤ 7 days) and late (> 7 days- 3-

5 months) onset Pneumonia and sepsis predominate early, may have

erythematous, nodular rash Late on set meningitis predominates

Listeriosis in pregnant woman, the elderly and immunocompromised is a foodborne illness Can present with flu-like symptoms or meningitis and

parenchymal brain illness, rhomboencephalitis (brain stem encephalitis), brain abscess and endocariditis

Treatment is with ampicillin with or without gentamicin for synergy

Case 2

5mo male with 2 day h/o tactile temps, irritability/decreased po intake. Temp 40oC in office: PE- nl. Pt UTD on immunizations, no ill contacts Any further w/u work up needed Differential Diagnosis

Considerations

Likelihood of this child having a serious bacterial illness (SBI) Pneumococcal bacteremia/ sepsis

Most commonly 6-24 mo continues to occur despite PCV7 but numerous reports with

decreased incidence Before Prevnar- 7 serotypes caused 80% of IPD now they cause

only 7% Reported IPD is 50% bacteremia, 30% pneumonia

Febrile child- Child-Pre Prevnar/HiB EraBaraff, et. al. Pediatr:1993;92:1-12 Febrile infants that are toxic appearing

1-3 months-17% probability of SBI 11% bacteremia with 4% meningitis

>3 months-10% probability of SBI Nontoxic infants still have 8.6% probability of SBI

2% bacteremia and 1% meningitis Low risk infants have 0.7-1.4% probability of SBI-when

these guidelines are applied to practice. Higher rates reflect SBI 2o Salmonella species and has been decreased with stool evaluation in patients with diarrhea

Negative predictive value 99.1%

Febrile Child-Post Prevnar/HiB Era 1.3-1.8 % rate of occult bacteremia from multiple studies Peds: 2004

75% decrease in invasive pneumococcal disease ≤ 2 yrs Up to 66% increase in rates related to NV serotypes and increased

Penicillin resistance JAMA: 2004

1.8% bacteremia 0.5% meningitis 5.4% UTI Predictors of SBI:

age <30 days higher temperatures ill appearance abnormal cry abnormal WBC count

Febrile Child-Post Prevnar/HiB Era PIDJ: 2005

Decreased rate of invasive pneumococcal disease 69% decrease in incidence 7.8 fold higher in infants < 12 mo, 2 fold higher in AA and

Hispanics 31% with co-morbid conditions 29% vaccine serotypes, 23-vaccine related 23% had 3 doses of vaccines

S. Pneumoniae Pre vs.Post Prevnar

Change in incidence from 1998-200380.0 cases per 100,000 population to 4.6, a decline of 94%

MMWR:September 16, 2005 / 54(36);893-897

S. Pneumoniae Pre vs.Post Prevnar Overall IPD dropped from 98.7

cases per 100,000 during 1998--1999 to 23.4 cases in 2005-77% decline Plateau 2002--2005 62,000 cases of IPD prevented

among children <5 years 53% prevented directly by vaccine

use Greatest decline in children <

12 mo

S. Pneumoniae Pre vs.Post Prevnar

Non-PCV7 strains are on the rise

Accounting for 1200 ICP cases

Predominant replacement strain 19A

Sur, D, et al. Evaluating Fever of Unidentifiable Source in Young Children, Am Fam Physician. 2007 Jun 15;75(12):1805-11

Case 3 9 yr old previously healthy female presents with a one day

history of fever and progressive lethargy. She has had a mild URI for the preceding 3 days. Findings on PE include Temp 39.5oC, a stiff neck, and a petechial rash. Your order a blood culture and perform a lumbar puncture.

The best initial treatment is 1. Ampicillin and gentamicin 2. Cefotaxime and gentamicin 3. Ceftazidime plus vancomycin 4. Ceftriaxone plus vancomycin 5. Vancomycin alone

Meningitis in Childhood

Most common etiology is viral Of bacterial causes Streptococcus pneumoniae and

Neisseria meningitidis are now the most common (post Hib and Prevnar)

Case 4 2.5yo presents w 4 day history of watery stools,

w/o blood or mucous associated with severe abdominal cramping. He has no fever/N/V/ and rest of ROS neg. He has had intermittent episodes of diarrhea for several weeks, and he c/o 1-2 times/week of cramping pain. His mother feels his stomach appears bigger/bloated. PE: nl except for distended abdomen Exposure h/o: attends daycare, several children have

had diarrhea, none currently, daycare went on a trip to a public park, kids did drink

from a water fountain about 6 days prior

Considerations

Significant exposures include Daycare attendance

Rotavirus, salmonella, shigella, giardia, other viral AGE Water from public fountain

Escherichia coli, cryptosporidium, trichlorethylene, perchlorethylene Contaminated water or food/vegetables

Escherichia coli

Epidemiology: what fits This episode could be AGE, but must R/O other

Giradia common in daycare centers, symptoms can be variable and intermittent, bloating and cramping common

E. coli some strains more common in this age group, easily spread person-person or contaminated water Usually very watery or bloody stools, cramping common, usually not

intermittent Dysentery strains less likely given clinical presentation (also shigella,

but salmonella could cause this). Cryptosporidium can cause symptoms in immunocompetent,

but usually self limiting

The Work up

Stool culture: neg for bacterial pathogens including E. coli O157:H7 Rotavirus neg Giardia EIA positive

The antigen test must be ordered separately from O + P and is positive in 80-90% from one stool specimen

Pt. treated with 7 days of metronidazole