Clinical Presentation of Leptospirosis in Outpatient Department
Leptospirosis typically presents in the outpatient department as a biphasic illness with fever, severe headache, muscle pain, conjunctival suffusion, and chills, with a wide clinical spectrum ranging from asymptomatic infection to severe disease with multi-organ failure. 1
Key Clinical Features
Initial Phase (Septicemic/Leptospiremic Phase)
- High fever (sudden onset)
- Severe headache
- Myalgia (particularly in calf and lumbar regions)
- Conjunctival suffusion (redness without exudate) - a distinctive feature
- Chills
- Skin rash/exanthema
- Nausea, vomiting, abdominal pain
- Non-productive cough
Secondary Phase (Immune Phase)
- Return of fever
- Jaundice (indicating liver involvement)
- Renal impairment (oliguria, anuria)
- Pulmonary manifestations (from subtle to severe hemorrhage) 2
Laboratory Findings
- Leukocytosis with left shift
- Thrombocytopenia
- Elevated liver enzymes
- Elevated bilirubin (in icteric cases)
- Elevated creatinine and BUN (in renal involvement)
- Proteinuria and microscopic hematuria
Severe Presentations (Weil's Syndrome)
Patients may progress to severe disease characterized by:
Diagnostic Approach
Blood cultures should be obtained within the first 5 days of illness for laboratory confirmation. Serological tests including agglutination titers between acute and convalescent sera are useful for diagnosis. 1
Risk Factors to Identify
- Travel to or residence in endemic areas
- Seasonal occurrence (often after heavy rainfall)
- Exposure to potentially contaminated water or soil
- Rodent exposure
- Occupational risks (agricultural workers, sewage workers) 1
Differential Diagnosis
- Dengue fever
- Malaria
- Typhoid fever
- Viral hepatitis
- Other causes of febrile thrombocytopenia 1
Red Flags Requiring Urgent Attention
- Jaundice with renal failure (significantly associated with mortality, odds ratio 1.2) 3
- Respiratory distress or hemoptysis (indicating pulmonary involvement)
- Altered mental status
- Hypotension or signs of shock
- Severe thrombocytopenia with bleeding manifestations 4, 5
Common Pitfalls
- Misdiagnosis as viral syndrome or other tropical diseases
- Delayed treatment due to low clinical suspicion
- Failure to obtain occupational and environmental exposure history
- Not considering leptospirosis in non-epidemic settings 4
Recognizing the biphasic nature of the disease is crucial, as patients may initially improve after the first phase only to deteriorate when the second phase begins. Early recognition and prompt antibiotic therapy are essential to prevent progression to severe disease with multi-organ involvement.