Leptospiral Pulmonary Haemorrhage Syndrome

Leptospiral pulmonary haemorrhage syndrome (LPHS) is a severe complication of leptospirosis caused by Leptospira interrogans, characterised by massive alveolar haemorrhage and respiratory failure.

• Complicates 5 to 10% of leptospirosis (higher in some outbreaks) and is the leading cause of death in severe disease, with a case fatality of 30 to 70%.
• Risk factors: exposure to floodwater, rodent urine, high bacterial load, serovar Icterohaemorrhagiae and Copenhageni, and delayed antibiotics.
• Occurs in tropical and subtropical regions (South-East Asia, Latin America, Pacific, parts of Africa) after heavy rainfall and flooding.

• Biphasic illness: septicaemic phase (fever, myalgia, calf pain, conjunctival suffusion, headache) followed on days 3 to 9 by immune phase with pulmonary involvement.
• Cough, haemoptysis (may be absent until late), dyspnoea, respiratory failure, and diffuse alveolar infiltrates.
• Weil syndrome features: jaundice, acute kidney injury, thrombocytopenia, and bleeding; myocarditis, arrhythmia, and shock.
• Rapid deterioration within hours.

• Clinical suspicion with exposure history; treat empirically.
• PCR on blood or urine (early), microscopic agglutination test (MAT; fourfold rise or titre of 1:400 or more), IgM ELISA, culture.
• Chest imaging: bilateral patchy alveolar infiltrates, ARDS pattern.
• Blood: thrombocytopenia, raised creatinine, bilirubin, CK, and hypokalaemia; arterial blood gas.
• Exclude hantavirus pulmonary syndrome, dengue haemorrhagic fever, ARDS from influenza, Goodpasture syndrome, vasculitis, and malaria.

• Immediate antibiotics: benzylpenicillin 1.5 million units IV every 6 hours, or ceftriaxone 1 to 2 g IV daily, or cefotaxime 1 g IV every 6 hours for 7 days; doxycycline 100 mg twice daily for mild cases.
• ICU care: early intubation with lung protective ventilation (tidal volume 6 mL/kg, plateau pressure under 30 cmH2O), higher PEEP, prone positioning, and ECMO for refractory hypoxaemia.
• Immunomodulation (evidence limited): methylprednisolone 1 g IV daily for 3 days, cyclophosphamide 1 g single dose, plasma exchange, or IVIG; used in specialised centres.
• Renal replacement therapy for acute kidney injury and fluid balance; transfuse for bleeding.
• Prevention: rodent control, protective footwear, doxycycline 200 mg weekly as chemoprophylaxis in high risk exposures.