Congenital TORCH infections

ToRCHHeS

Feature	Toxoplasma gondii	Rubella	Cytomegalovirus (CMV)	HIV	HSV-2	Syphilis	Streptococcus (GBS)
Pathogen Type	Parasite	Virus	Virus (Herpesvirus)	Virus (Retrovirus)	Virus (Herpesvirus)	Bacterium (Treponema pallidum)	Bacterium (Streptococcus agalactiae)
Classic Triad/Presentation	Chorioretinitis, hydrocephalus, diffuse intracranial calcifications	Cataracts, heart defects, sensorineural hearing loss	No classic triad, but periventricular calcifications, microcephaly, and SNHL are characteristic.	No classic triad; failure to thrive, recurrent infections, and developmental delay are common	No classic triad; skin/mucous membrane lesions, encephalitis, or disseminated infection characterize.	Early: "Snuffles," rash, bone lesions, lymphadenopathy and hepatosplenomegaly; Late: Hutchinson teeth, interstitial keratitis, saddle nose, saber shins	Early-onset: Respiratory distress, sepsis, pneumonia, meningitis (within first week, usually <24 hrs); Late-onset: Bacteremia, meningitis (after first week)
Other Key Differentiators	Often asymptomatic at birth, later chorioretinitis. Linked to cat feces/undercooked meat.	"Blueberry muffin" rash, often mild maternal illness. Preventable by MMR vaccine.	Most common congenital viral infection. Hearing loss can be late-onset.	Opportunistic infections are a hallmark. ART is crucial for prevention.	Vesicular lesions (but not always present). Often acquired during birth.	Multisystem; early/late manifestations differ. Penicillin is treatment.	Leading cause of neonatal sepsis/meningitis. Maternal colonization is key risk factor. Intrapartum antibiotics prevent early-onset disease.
Transmission	Transplacental, ingestion	Transplacental, respiratory	Transplacental, body fluids	Transplacental, birth, breastfeeding	Primarily during birth	Transplacental, birth	Vertical transmission during birth (primarily), ascending infection, rarely nosocomial/community-acquired (late-onset)

Tip

All TORCH infections can cause blueberry muffin rash, except GBS.

# Congenital rubella infection

Clinical features

Intrauterine rubella infection: miscarriage, preterm birth, fetal growth restriction (especially likely if infection occurs during the first trimester)
Congenital rubella syndrome
- Triad of congenital rubella syndrome
  - Cardiac defect: most common defect (e.g., patent ductus arteriosus, pulmonary artery stenosis)
  - Cataracts: Other eye manifestations may also occur later in life, including glaucoma and salt and pepper retinopathy (abnormal retinal pigmentation)
  - Cochlear defect: bilateral sensorineural hearing loss
- Early features
  - Hepatosplenomegaly, jaundice
  - Hemolytic anemia, thrombocytopenia
  - Petechiae and purpura, i.e., blueberry muffin rash (due to extramedullary hematopoiesis in the skin)
- Late features
  - CNS defects: microcephaly, intellectual disability, panencephalitis
  - Skeletal abnormalities

Mnemonic

CCC-Triad of congenital rubella syndrome: Cataracts, Cochlear defects, Cardiac abnormality

Prevention
- Maternal preconception immunization with live attenuated rubella vaccine

# Congenital syphilis

Pathogen

Treponema pallidum

Transmission

Fetus: transplacental transmission from infected mother
Neonate: perinatal transmission during birth

Clinical features of congenital syphilis

Perinatal
- Intrauterine fetal demise
- Prematurity, low birth weight
- Focal necrosis of the umbilical cord
Mucocutaneous
- Snuffles: copious rhinorrhea, often purulent or serosanguineous
- Desquamating, maculopapular rash involving palms/soles
- Fissures near orifices (eg, anal, oral)
- Jaundice
Musculoskeletal
- Long bone abnormalities (eg, periosteal thickening, metaphyseal erosion)
  - Bilateral and symmetric metaphyseal erosions and periosteal inflammation of long bones
  - Pathologic fractures
  - Swelling, pain, and limited movement of affected extremities
Reticuloendothelial
- Hepatomegaly ± splenomegaly
- Lymphadenopathy
- Anemia, thrombocytopenia, leukopenia/leukocytosis