Makindo Medical Notes

🌡️ About

• Typhoid Fever: Caused by Salmonella typhi.
• Paratyphoid Fever: Caused by Salmonella paratyphi (A, B, C).

🦠 Aetiology

• Transmission: Faeco-oral (contaminated food/water).
• Children aged 1–5 yrs particularly vulnerable.
• Gallbladder = reservoir in chronic carriers.
• Pathology: Peyer’s patches in ileum → swelling, ulceration → intestinal bleeding/perforation in severe cases.

🔬 Key Microbiology

• Gram-negative, motile rod, facultative anaerobe.
• Ferments glucose, oxidase-negative, catalase-positive.
• Reduces nitrates → nitrites.
• Non-lactose fermenter → pale colonies on MacConkey agar.
• Resistant to bile salts (sodium deoxycholate).

🩺 Clinical Presentation

• Incubation: 10–14 days (typhoid); shorter in paratyphoid.
• Week 1: Dry cough, malaise, headache, stepwise fever (→ 39°C), constipation/diarrhoea, relative bradycardia 🚨.
• Week 2: Rose spots (trunk), splenomegaly, hepatomegaly, lymphadenopathy, epistaxis, persistent bradycardia.
• Week 3: Complications – bowel haemorrhage, perforation, toxaemia, cholecystitis, osteomyelitis (esp. sickle cell), myocarditis, nephritis, meningitis, pneumonia.
• Week 4: Recovery (if untreated), but some → prolonged illness or carrier state.
• Paratyphoid: Shorter, milder, rash more prominent, intestinal complications less common.

⚠️ Clinical clue: Relative bradycardia + low WCC despite fever.
🧒 Sickle cell children → high risk of Salmonella osteomyelitis.

🧪 Investigations

• FBC: Low WCC, raised AST/ALT.
• Blood cultures: Positive in 1st–2nd week.
• Stool cultures: Positive from 2nd week onward.
• Urine cultures: May also be positive.
• Widal test: Obsolete/unreliable.

💊 Management

• Duration untreated: Typically ≥4 weeks.
• Infection control: Side room isolation, strict hygiene.
• First-line antibiotics:
  • Ciprofloxacin 500–750 mg BD PO × 10 days (up to 500 mg QDS).
  • Alternative if resistance suspected → Azithromycin 500 mg OD × 10–14 days.
• Chronic carriers: Ciprofloxacin 500 mg BD PO × 4 weeks.
  If fails → consider cholecystectomy.
• Public health: Notifiable disease 🚨 → inform HPA/UKHSA.
• Food handling: No return until 3 consecutive negative stool cultures.

🛡️ Prevention

• Vaccination (IM polysaccharide) recommended for travellers to endemic regions.
• Safe food, clean water, strict hygiene.