Neonatal tuberculosis

Background

• Infection of a neonate by Mycobacterium tuberculosis

Pathophysiology

• May be either acquired antenatally as congenital tuberculosis, via hematogenous dissemination from a mother with either miliary or primary TB, or post-natally as neonatal tuberculosis, via the usual airborne mechanism

Clinical Presentation

• Similar presentation for both congenital and neonatal tuberculosis
• Symptoms may take 1 to 2 weeks to develop (congenital) or several months (neonatal)
• Hepatomegaly, splenomegaly, respiratory distress, fever, lymphadenopathy, abdominal distension, lethargy, irritability, poor feeding and ear discharge
• Congenital TB may also have low birth weight
• Miliary or nodular pattern with hilar lymphadenopathy on chest x-ray

Differential Diagnosis

• Symptoms at birth
  • Congenital TORCH infection (toxoplasmosis, rubella, cytomegalovirus, herpes, etc.)
  • Congenital syphilis
  • Hemophagocytic lymphohistiocytoysis (HLH)
• Presentation after several weeks
  • Late-onset bacterial infection

Diagnosis

• Can be difficult if mother does not have a history of TB
• Based on chest x-ray plus clinical picture
• TST and IGRA are typically negative in neonatal period
• Send sputum or gastric aspirates for smear and culture ± PCR
  • Can also send ascitic or pleural fluid, or blood, as indicated
  • Newborns with suspected or proven disseminated TB need lumbar puncture
• Placental histopathology and culture, if possible

Management

• Treat empirically
• Standard treatment with isoniazid 10 mg/kg po daily, rifampin 15 mg/kg po daily, pyrazinamide 35 mg/kg po daily, and ethambutol 20 mg/kg po daily for 2 months, followed by isoniazid and rifampin alone for another 4 months
  • If low prevalence of isoniazid resistance and disease is not extensive, no need for ethambutol during initial treatment
• There are specific treatment considerations for drug-resistant tuberculosis and tuberculous meningitis