What is the appropriate treatment plan for a patient presenting with suspected or confirmed typhoid fever?

SOAP Note for Typhoid Fever

Subjective

Chief Complaint:

• Fever for 7-18 days (typical incubation period), though range can be 3-60 days 1

History of Present Illness:

• Fever is almost invariable - patient may report continuous or intermittent fever 1
• Non-specific symptoms including headache, malaise, lethargy, and abdominal pain 1
• Constipation OR diarrhea (diarrhea is actually uncommon in enteric fever) 1
• Dry cough may be present 1
• Note: Patient may be afebrile on presentation despite fever history 1

Critical Travel/Exposure History:

• Recent travel to South/Southeast Asia (highest incidence), Central/South America, Africa, or Oceania 1
• Consumption of food prepared by individuals with recent endemic exposure 1
• 68% of S. Typhi cases and 50% of S. Paratyphi cases report travel history 1

Red Flags for Complications (if illness >2 weeks):

• Confusion, seizures, or decreased Glasgow Coma Scale (cerebral malaria or hypoglycemia) 1
• Gastrointestinal bleeding or severe abdominal pain (perforation risk) 1, 2

Objective

Vital Signs:

• Temperature: Document fever pattern
• Blood pressure and heart rate: Assess for sepsis/shock

Physical Examination:

• Hepatosplenomegaly - present in established disease 1
• Abdominal tenderness without peritoneal signs (unless perforation) 1
• Mental status: Assess for stupor or encephalopathy 1
• Meningism may occur (misleading symptom) 1

Laboratory Findings:

• Full blood count and liver function tests may be normal or deranged in almost any pattern 1
• Elevated aspartate aminotransferase (especially with nalidixic acid-resistant strains) 3

Assessment

Diagnosis: Suspected/Confirmed Typhoid Fever (Enteric Fever)

Diagnostic Workup:

• Blood cultures BEFORE antibiotics - highest yield within first week of symptoms (40-80% sensitivity) 1, 2
• Stool and urine cultures - become positive after first week (lower sensitivity: stool 35-65%, urine 0-58%) 1
• Bone marrow culture if blood cultures negative and high suspicion (higher sensitivity than blood) 1
• Do NOT use Widal test - lacks sensitivity and specificity 1
• Newer rapid serological tests (Typhidot, Tubex) have shown mixed results 1

Antibiotic Susceptibility Testing:

• Critical: Ciprofloxacin disc testing is unreliable - organism must also be sensitive to nalidixic acid to be considered fluoroquinolone-sensitive 1
• Over 70% of S. typhi/paratyphi isolates from Asia are fluoroquinolone-resistant 1, 2

Complications to Monitor (occur in 10-15% of patients, more likely if illness >2 weeks):

• Gastrointestinal bleeding 1, 2
• Intestinal perforation 1, 2
• Typhoid encephalopathy 1, 2

Plan

Immediate Management

For Clinically Unstable Patients or Strong Suspicion:

• Start empiric IV ceftriaxone 50-80 mg/kg/day (maximum 2g/day) immediately after blood cultures 1, 2
• Do NOT use empiric fluoroquinolones for cases from South/Southeast Asia due to >70% resistance 1, 2, 4

Definitive Antibiotic Therapy

First-Line Treatment (based on geographic origin and severity):

For Severe/Hospitalized Cases:

• Ceftriaxone 50-80 mg/kg/day IV (maximum 2g/day) for 5-7 days, then switch to oral when afebrile for 24 hours 2, 4, 5
• Total treatment duration: 14 days to reduce relapse risk 1, 2
• Expected fever clearance: 4 days average 1, 5
• Relapse rate with ceftriaxone: <8% 1, 2

For Uncomplicated Cases:

• Azithromycin 20 mg/kg/day (maximum 1g/day) orally for 7 days 2, 4
• Relapse rate with azithromycin: <3% 1, 2
• Lower risk of clinical failure compared to fluoroquinolones 2, 4

For Fluoroquinolone-Sensitive Isolates ONLY (if nalidixic acid sensitive):

• Ciprofloxacin or ofloxacin for 14 days 1, 4
• Fever clearance time <4 days, cure rates >96% 1
• Do NOT use empirically - resistance is widespread 1, 2, 4

Alternative Oral Agent (if confirmed fluoroquinolone-resistant):

• Azithromycin as oral follow-on agent 1, 2
• Cefixime 8 mg/kg/day (maximum 400mg) has treatment failure rates of 4-37.6% - less preferred 1, 4

Adjunctive Therapy

For Severe Cases:

• Consider steroids for severe/toxic presentations 1, 6

Supportive Care:

• Monitor fluid and electrolyte balance 4
• Nutritional support 6

Monitoring

Clinical Response:

• Expect defervescence within 4-5 days of appropriate therapy 4, 5
• If no response within 24-48 hours, consider alternative diagnoses or resistant organism 1

Complications Surveillance:

• Daily abdominal examination for perforation signs 1, 2
• Monitor for gastrointestinal bleeding 1, 2
• Neurological assessment for encephalopathy 1, 2

Follow-Up

Post-Treatment:

• Monitor for relapse for 1-8 months 5
• Assess for chronic carrier state (positive stool cultures >1 year after infection) 6
• Counsel on hygiene and food handling if carrier state develops 6

Critical Pitfalls to Avoid

• Never use empiric fluoroquinolones for cases from South/Southeast Asia - >70% resistance 1, 2, 4
• Never rely on Widal test for diagnosis - poor sensitivity and specificity 1
• Never use ciprofloxacin disc alone for susceptibility - must check nalidixic acid sensitivity 1
• Never treat for <14 days - increases relapse risk 1, 2
• Never delay antibiotics in unstable patients - start empirically after cultures 1, 2