A 35-year-old woman from Mumbai with enteric fever (confirmed by blood culture for Salmonella typhi) develops high fever, altered mental status, and signs of meningitis on day 5 of illness. Lumbar puncture shows lymphocytic pleocytosis. What is the drug of choice for this complicated enteric fever with encephalitis?

Explanation

## Drug of Choice for Complicated Enteric Fever (Encephalitis) ### Shift in Treatment Strategy for Severe/Complicated Disease **Key Point:** When enteric fever is complicated by encephalitis, meningitis, myocarditis, intestinal perforation, or septic shock, third-generation cephalosporins (ceftriaxone or cefotaxime) become the drug of choice, displacing fluoroquinolones. ### Why Ceftriaxone for Complicated Enteric Fever? 1. **Superior CNS penetration:** Achieves therapeutic levels in cerebrospinal fluid (CSF), essential for meningitis/encephalitis. 2. **Bactericidal activity:** Rapidly kills Salmonella in CNS and systemic circulation. 3. **Resistance profile:** Minimal resistance in S. typhi; effective against MDR and NAR strains. 4. **Dosing in meningitis:** Ceftriaxone 2 g IV Q4–6H (higher doses for CNS penetration). 5. **Parenteral route:** IV administration ensures high serum and CSF levels. ### Comparison of Agents in Complicated Enteric Fever | Agent | CNS Penetration | Efficacy in Encephalitis | Current Role | |-------|-----------------|--------------------------|---------------| | Ciprofloxacin (FQ) | Moderate | Suboptimal in meningitis | First-line for uncomplicated only | | Ceftriaxone (3rd-gen) | Excellent | Gold standard | **DOC for complicated disease** | | Chloramphenicol | Good | Historically used; now obsolete | Resistance + toxicity; avoid | | Azithromycin | Poor | Inadequate | Not recommended; no role | **High-Yield:** The **clinical presentation of encephalitis** (altered mental status, meningeal signs, CSF pleocytosis) is the trigger to **switch from fluoroquinolone to cephalosporin**, even if the patient was initially on ciprofloxacin. ### Clinical Pearl **Warning:** Do NOT continue ciprofloxacin in a patient who develops CNS complications. The moderate CSF penetration of fluoroquinolones is insufficient for meningitis/encephalitis. Immediate switch to ceftriaxone is mandatory. **Mnemonic — COMP-CEPH:** **COMP**licated enteric fever → **CEPH**alosporin (3rd-gen). ### Duration and Adjunctive Therapy - **Duration:** 10–14 days IV ceftriaxone (longer than uncomplicated disease). - **Adjuncts:** Dexamethasone may be considered to reduce inflammation and improve outcomes in enteric encephalitis. - **Supportive care:** ICU monitoring, management of seizures, cerebral edema. [cite:Harrison 21e Ch 155; Park 26e Ch 32]