Infections, CNS | The Massachusetts General Hospital Handbook of Neurology

Authors: Flaherty, Alice W.; Rost, Natalia S.

Title: Massachusetts General Hospital Handbook of Neurology, The, 2nd Edition

> Table of Contents > Child Neurology > Infections, CNS

Infections, CNS

F. Meningitis

See also meningitis in adults, p. 56.

H&P: Irritability or somnolence, fever, cyanosis, high-pitched cry, poor feeding, sometimes a bulging fontanelle or seizures. Before 1 yr of age, there is usually no meningismus; after that, you may see HA, stiff neck, Kernig's or Brudzinski's sign. Look for rash, mouth or ear lesions.
DDx: Mass lesion, including abscess, toxic exposure
Tests: CBC, electrolytes, blood cultures. LP, usually with prior head CT. See Table 3, p. 19, for CSF findings. Never delay empiric Abx; LP can be done up to 2 h after first dose without destroying culture results.

Rx:

Empiric Abx: These suggestions are heavily influenced by vaccine use and do not apply outside the United States. Adjust on basis of culture and sensitivities.

Table 40. Empiric antibiotics for pediatric meningitis. (Adapted from Tunkel AR, et al. Clin Infect Dis. 2004;39:1267-1284.)

Patient	Likely Pathogen	Antibiotic
1 mo	S. agalactiae, E. coli, L. monocytogenes, Klebsiella	Ampicillin + (cefotaxime or aminoglycoside)
1 mo-2 yr¹	S. pneumo., H. influenzae, E. coli, N. meningitides, L. monocytogenes	Vancomycin + (ceftri-axone or cefotaxime)
2-50 yr¹	N. meningitidis, S. pneumo.	Vancomycin + (ceftri- axone or cefotaxime)
Head trauma, surgery, shunt	Staph, gram-neg. bacilli, or pneumococcus	Vancomycin + (cefepime, cef-tazidime, or meropenem)
¹Most infants and children need only vancomycin unless gram stain has gram-negative bacilli.

Respiratory precautions if you suspect N. meningitidis.
Dexamethasone: 20 min before, or at least with, the first Abx dose, at 0.15 mg/kg every 6 h for 2-4 d, or until pathogen determined. Helps H. influenzae primarily. No point in starting it after the first dose of Abx.

P.142

G. TORCH infections

Acronym for the major nonbacterial infections of neonates: Toxoplasmosis, Others (especially syphilis), Rubella, Cytomegalovirus, and Herpes simplex. All are acquired transplacentally except herpes, which the fetus catches in the birth canal.

Toxoplasmosis:
- H&P: Signs of diffuse cortical and subcortical lesions. Cataracts, microphthalmia. Sometimes liver, marrow, lung, muscle, and heart problems.
- Tests: Cerebral cortex and periventricular necrosis and calcification on CT; watch for hydrocephalus. Toxoplasma-specific IgM is often negative. CSF may show lymphocytosis, high protein, and trophozoites.
- Rx: Spiramycin, pyrimethamine, and sulfadiazine to infected mother and baby during the first year. Infected infants are highly infectious.
Rubella: Congenital rubella syndrome occurs when the fetus is infected <20 wk gestation.
- Mild cases: Normal at birth, then show CNS and ocular deficits, deafness, and heart dz.
- Severe cases: Low birth weight, liver failure, petechiae, cataracts, deafness, heart dz, microcephaly, bone lesions, and low platelets.
- Tests: Viral culture of throat and urine. Serum rubella IgM.
- Rx: Symptomatic.
Cytomegalovirus:
- H&P: Only 10% of infected newborns are symptomatic at birth (liver failure, petechiae, microcephaly, periventricular calcifications, chorioretinitis). Of the 90% who are asymptomatic, 10% will later get deafness or microcephaly.
- Tests: Urine culture.
Herpes simplex: Maternal hx may be absent for newborns since mother sheds virus before lesions are visible.
- H&P: Local oral or ophthalmic lesions (both may be absent), meningitis, or disseminated HSV with hepatosplenomegaly, DIC, renal failure, and encephalitis.
- Tests: CSF is consistent with viral meningitis, and CSF HSV PCR+. Throat, urine, and stool cultures.
- Rx: 14 days of acyclovir, 60 mg/kg/d, div tid for neonates. Do not wait for culture results to start.