What is the examination protocol for a patient suspected of having typhoid fever?

Typhoid Fever Examination Protocol

For patients with suspected typhoid fever, immediately obtain blood cultures (ideally within the first week of symptoms), perform a focused physical examination for fever, relative bradycardia, hepatosplenomegaly, and abdominal tenderness, and assess for neurologic complications—do not rely on the Widal test alone for diagnosis. 1, 2

Clinical History Assessment

Obtain specific information about:

• Travel history: Recent travel to South or Southeast Asia where incidence exceeds 100 cases per 100,000 person-years 1
• Fever pattern: Duration and characteristics (sustained high-grade fever present in 97-100% of cases, though the classic "step-ladder" pattern is unreliable) 1
• Constitutional symptoms: Headache, malaise, myalgia, and anorexia 1
• Gastrointestinal symptoms: Constipation or diarrhea, abdominal pain, vomiting 1, 3
• Respiratory symptoms: Nonproductive cough 1
• Timeline: Incubation period is typically 7-18 days (range 3-60 days) with insidious rather than abrupt onset 1

Physical Examination Components

Vital Signs

• Temperature: Document fever (present in 97-100% of cases) 1
• Pulse: Assess for relative bradycardia (pulse slower than expected for degree of fever) 1

Abdominal Examination

• Palpation: Check for hepatomegaly and splenomegaly 3, 4
• Tenderness: Assess for diffuse abdominal tenderness, particularly in the right lower quadrant 5
• Peritoneal signs: Critical to detect intestinal perforation, which typically occurs in the third week if untreated 1

Neurologic Examination

• Mental status: Assess for encephalopathy, confusion, or coma (13% of cases may have neurologic manifestations) 1, 6
• Motor examination: Check for upper motor neuron signs including hyperreflexia, spasticity, or sustained ankle clonus (43% of neurologic cases) 6
• Coordination: Assess for ataxia (present in 55% of neurologic cases) 6
• Movement disorders: Evaluate for parkinsonism (20% of neurologic cases) or tremors (10% of neurologic cases) 6

General Examination

• Skin: Assess for rose spots (though often absent)
• Overall appearance: Document degree of toxicity and prostration 7

Laboratory Investigations

Essential Diagnostic Tests

Blood cultures (gold standard):

• Obtain before initiating antibiotics 2
• Highest yield within the first week of symptoms 1, 2
• Collect multiple sets (at least 2-3) to increase sensitivity 3, 7
• Sensitivity is 65.3% in confirmed cases but may be negative in 87.5-95% of cases 2, 4

Complete blood count:

• Assess for leukopenia, lymphocytopenia, and thrombocytopenia (common findings) 7, 4
• Check for anemia 4

Liver function tests:

• Elevated transaminases are common 3
• Document hepatitis pattern 7

Additional Laboratory Tests

Stool and urine cultures:

• Collect if blood cultures are negative 2
• Urine culture may be positive 7

Renal function:

• Creatinine and BUN to assess for acute renal failure (rare complication) 5

Muscle enzymes:

• Creatine kinase and myoglobin if rhabdomyolysis suspected 5

Pancreatic enzymes:

• Amylase and lipase if acute pancreatitis suspected 5

Tests to Avoid or Interpret Cautiously

Widal test limitations 2:

• Not sufficient for diagnosis alone per CDC guidelines 2
• False positives occur from: prior typhoid vaccination, previous typhoid infection, other febrile illnesses, cross-reactions with other Salmonella species 2
• False negatives occur from: prior antibiotic treatment, immunosuppression 2
• Background antibody levels may be elevated in endemic areas, reducing specificity 2

Rapid dipstick assays:

• Sensitivity 58%, specificity 98.1% (lower than culture but higher than Widal test) 4
• May be used when culture facilities unavailable, but should not replace blood culture when available 4
• Sensitivity increases with duration of illness and is higher in culture-positive patients 4

Critical Pitfalls to Avoid

• Do not delay blood cultures: Obtain before antibiotics, as prior antibiotic use reduces sensitivity 2, 4
• Do not rely on Widal test alone: Requires culture confirmation per CDC guidelines 2
• Do not dismiss neurologic symptoms: 13% of cases have objective neurologic findings, which may be the presenting feature 6
• Do not overlook immunocompromised patients: High-risk groups including those with chronic liver disease require heightened suspicion 1
• Do not miss complications: Examine carefully for signs of intestinal perforation (typically third week), gastrointestinal bleeding, or septic shock 8, 1, 7

Special Considerations for Empiric Treatment

Initiate empiric antibiotics after culture collection in patients with:

• Clinical features of sepsis 8
• Severe illness with documented fever ≥38.5°C in travelers from endemic areas 8
• Signs of septic shock or encephalopathy 7

Empiric therapy should be fluoroquinolone (ciprofloxacin) or azithromycin depending on local resistance patterns, or third-generation cephalosporin (ceftriaxone) for severe cases 8, 3, 7