Congenital infections, neonatal sepsis and conjunctivitis: board review

Recognize the congenital infection: TORCH, syphilis and parvovirus

Whatever the clue, the next step is the same: test the infant directly with the right PCR or serology, and test early.

• Toxoplasmosis prevention in pregnancy: someone else changes the cat litter daily (or wear gloves), cook meat well, wash produce and hands after gardening.
• Rubella is prevented by MMR before pregnancy; MMR is not given during pregnancy.
• Suspect congenital syphilis with snuffles, palm and sole rash, hepatosplenomegaly or bone changes, especially with no prenatal care.
• Compare the infant's serum RPR (not cord blood) with the mother's; an infant titer fourfold higher than the mother's confirms likely infection.
• Treatment: aqueous penicillin G 50,000 units/kg IV every 12 hours in the first 7 days of life, then every 8 hours, for 10 days. Procaine penicillin 50,000 units/kg IM daily for 10 days is an alternative.
• If more than 1 day of treatment is missed, restart the whole course.
• Parvovirus B19 infects red-cell precursors: fetal red-cell production stops, causing severe anemia, high-output heart failure and nonimmune hydrops.
• Pregnant person exposed to a child with slapped-cheek rash: check parvovirus IgG and IgM. If acute infection, follow the fetus with serial middle cerebral artery Doppler for anemia.

Congenital and postnatal CMV

• CMV is the most common congenital infection and the leading non-genetic cause of sensorineural hearing loss.
• Diagnose congenital CMV with urine PCR (or saliva PCR confirmed by urine) in the first 21 days of life.
• CMV IgG in the newborn has no role: it is maternal antibody.
• A negative dried blood spot PCR does not exclude congenital CMV (low sensitivity); a positive one confirms it.
• Moderate to severe symptomatic disease: oral valganciclovir for 6 months, starting in the first month. Watch for neutropenia.
• Blood viral load is used to monitor treatment, not to diagnose.
• Follow hearing and eyes: hearing loss can appear or worsen later.
• Postnatal CMV: negative tests in the first 3 weeks, positive after 21 days. It affects very-low-birth-weight preterm infants, usually from their mother's breast milk.
• Postnatal CMV looks like sepsis with neutropenia, thrombocytopenia, raised transaminases, hepatitis or pneumonitis. Confirm with urine PCR.
• Breast milk benefits still outweigh the risk; freezing or pasteurizing milk lowers it.

Neonatal HSV and neonatal varicella

Most neonatal HSV is caught during delivery, often from a mother with no known history of herpes. It presents in the first 1–3 weeks as skin-eye-mouth disease, CNS disease or disseminated disease; many babies never have vesicles.

• Grouped vesicles, including at a scalp-monitor site: start IV acyclovir 60 mg/kg/day divided every 8 hours right away; do not wait for PCR.
• Add acyclovir to a septic neonate who is not improving on ampicillin and a cephalosporin, or who has seizures, raised ALT or CSF pleocytosis.
• Work-up: surface swabs PCR, blood PCR, CSF PCR and ALT.
• MRI in HSV encephalitis may show temporal-lobe edema and hemorrhagic necrosis.
• Treat 14 days for skin-eye-mouth disease and 21 days for CNS or disseminated disease (repeat CSF PCR before stopping in CNS disease), then oral acyclovir suppression for 6 months.
• Maternal varicella rash from 5 days before to 2 days after delivery: the baby gets virus without maternal antibody. Give VariZIG as soon as possible, and IV acyclovir if disease develops.

Neonatal sepsis, GBS, Listeria and Candida

• GBS prevention: vaginal-rectal culture at 36 0/7–37 6/7 weeks. Intrapartum penicillin or ampicillin (or cefazolin) at least 4 hours before delivery is adequate; clindamycin or vancomycin alone is not.
• Intrapartum prophylaxis prevents early-onset GBS only, not late-onset disease.
• Listeria is intrinsically resistant to all cephalosporins, and vancomycin is not a substitute: ampicillin is required.
• Pregnant people, newborns and immunocompromised people have the highest risk of invasive Listeria; pregnant people should avoid unpasteurized milk, soft cheese, deli meats, hot dogs (unless steaming hot) and smoked seafood.
• Empiric early-onset sepsis therapy: ampicillin plus gentamicin. For meningitis, add a broad-spectrum cephalosporin such as cefepime or ceftazidime.
• Avoid ceftriaxone in neonates: it displaces bilirubin from albumin and precipitates with IV calcium.

Newborn conjunctivitis and chlamydial pneumonia

• Timing: chemical conjunctivitis within 24 hours, gonococcal on day 2–5, chlamydial on day 5–14.
• Prevention: erythromycin 0.5% ophthalmic ointment to both eyes at birth prevents gonococcal ophthalmia, not chlamydial infection.
• Gonococcal ophthalmia (copious pus): Gram stain and culture, then treat at once without waiting for results.
• Treatment: ceftriaxone 25–50 mg/kg IV or IM once (maximum 250 mg). Topical treatment alone is not enough. Look for disseminated infection.
• If the infant receives IV calcium or has high bilirubin, use cefotaxime 100 mg/kg once instead.
• Evaluate and treat the mother and her partners for STIs.
• Chlamydial conjunctivitis or pneumonia: oral azithromycin 20 mg/kg once daily for 3 days, or erythromycin for 14 days. Oral, not topical, because nasopharyngeal carriage causes pneumonia.
• Chlamydial pneumonia: afebrile infant aged 1–3 months with staccato cough, hyperinflation with interstitial infiltrates and peripheral eosinophilia.
• Macrolides in the first weeks raise the risk of pyloric stenosis; watch for vomiting.

The well-appearing febrile infant 8–60 days

The AAP 2021 guideline applies to well-appearing term infants with a temperature of 100.4 °F (38.0 °C) or higher. It uses 3 age groups: 8–21 days, 22–28 days and 29–60 days. E. coli is the top cause of bacteremia and UTI; GBS remains a top cause of meningitis.

• 8–21 days: urinalysis (and urine culture), blood culture and CSF analysis and culture, even if inflammatory markers are normal. Admit and give parenteral antibiotics.
• 22–28 days: urine and blood culture plus inflammatory markers; LP is done when markers are abnormal and may be done when they are normal.
• 29–60 days: urine, blood culture and inflammatory markers; many can go home with close follow-up if all are reassuring.
• Procalcitonin is the preferred marker (abnormal above 0.5 ng/mL); others are CRP above 2.0 mg/dL and ANC above 4,000/µL.
• A positive urinalysis is any leukocyte esterase or pyuria.
• Discharge after admission when cultures are negative at 24–36 hours, the infant is well and follow-up is arranged.

Maternal infection and breastfeeding

Common questions

Sources

• AAP 2021: Evaluation and management of well-appearing febrile infants 8 to 60 days old (Pediatrics)
• AAP 2019: Management of infants at risk for group B streptococcal disease (Pediatrics)
• CDC 2021: Sexually transmitted infections treatment guidelines (MMWR)
• Congenital cytomegalovirus infection: international consensus recommendations (Lancet Infect Dis 2017)
• AAP 2022: Policy statement on breastfeeding and the use of human milk (Pediatrics)

Written for Pedemy in our own words from the sources above; checked November 2026. For education only, not medical advice; check doses and local protocols before treating a patient. Pedemy is independent and not affiliated with or endorsed by the organizations cited.