Invasive Salmonella Disease: Typhoid fever and NTS sepsis

Background

Typhoid (caused by Salmonella Typhi) and Non Typhoidal Salmonella (NTS) sepsis (Salmonella Typhimurium or Enteritidis) have caused outbreaks of febrile disease in Malawi. The clinical pictures of Typhoid and NTS sepsis can be similar.
Typhoid fever typically occurs in school aged children and young adults but all ages can be affected. NTS sepsis has a bimodal age distribution: it typically affects young children and older, immunocompromised adults. NTS bacteraemia is associated with malaria, severe anaemia or a combination of both, with malnutrition and with HIV. Both malaria and Salmonella diseases have a seasonal peak in the rainy season.

Salmonella isolates at QECH exhibit multiple drug resistance to antibiotics that
are commonly used in the community (Ampicillin, Cotrimoxazole, Chloramphenicol).

Symptoms

• Non-specific with fever - can last several weeks if untreated
• Headache, abdominal or back pain
• Constipation, diarrhoea, nausea, vomiting
• Weight loss - can be very dramatic.
• Jaundice, tender hepatomegaly and cholecystitis
• Dry cough - occasionally focal chest signs
• Dizziness, confusion, or an encephalitis/ meningitis-like picture

Complications

Common:

• Hepatitis
• Intestinal perforation (consider in child with typhoid and abdominal
  distension who develops shock) or GI bleeding
• Thrombocytopenia/ anaemia/ leucopenia - or pancytopenia

Rarely:

• Septic arthritis/ meningitis / myocarditis

Investigations

• Blood cultures are the gold standard but sensitivity is about 50% so a negative blood culture result does not rule out Salmonella disease in a symptomatic patient
• FBC - anaemia, leucopenia, thrombocytopenia, pancytopenia
• MPS or MRDT
• HIV test (NTS sepsis is Stage III disease, therefore patients qualify for ARTs. Recurrent NTS sepsis is stage IV disease)
• CXR/ AXR for air under diaphragm if perforation suspected

Treatment

• Preferably Ciprofloxacin 30 mg/kg daily in two divided doses, maximum 1000 mg/day either orally or parenterally 20 mg/kg daily in two divided doses, maximum 800 mg/day for 7 to 10 days or
• If the response to treatment is poor after 48 h, consider drug-resistant typhoid, and treat with second-line antibiotic. Ceftriaxone 100 mg/kg per day intravenously once daily, maximum 2 gr/day for 10 to 14 days.

Give a full course of Ciprofloxacin to patients who have had only a few days of Ceftriaxone.