Therapeutic Plasma Exchange (TPE) in Severe Leptospirosis- Application, Factors Affecting Its Life-Saving Benefits and Outcome: A Case Series from Sri Lanka

Background: Leptospirosis is a globally prevalent zoonosis with significant morbidity and mortality, especially in tropical regions like South Asia. In its severe form, the disease often leads to multiorgan dysfunction, with pulmonary haemorrhage being a significant cause of death. Evidence supporting specific treatments for severe leptospirosis with pulmonary involvement remains limited. Recent studies suggest that immunomodulatory therapies, such as therapeutic plasma exchange (TPE), may offer survival benefits. This case series examines the application and outcomes of TPE in patients with severe leptospirosis at a tertiary-care hospital in Sri Lanka. Methods: We studied a case series involving 10 patients with confirmed severe leptospirosis and multiorgan involvement, from September 2021 to October 2022. All patients received intravenous antibiotics and methylprednisolone. TPE was initiated in nine patients based on clinical severity, particularly in the presence of pulmonary haemorrhage. Clinical, laboratory, and radiological data were collected from patient records and follow-up. ELISA IgM confirmed Leptospirosis. A multidisciplinary team made TPE decisions. Results: Of the nine patients who received TPE, seven survived (77.8%). Pulmonary haemorrhage was the primary indication for TPE in all the cases. All patients had multiorgan involvement: renal failure (90%), hepatic dysfunction (60%), and myocarditis (70%). Mortality was associated with inotropic-dependent myocarditis and mechanical ventilation at TPE initiation. Patients requiring intubation had a 50% mortality rate, compared to 14.3% in those who were not intubated. Non-survivors also had elevated lactate levels (>4 mmol/L) and worsening acid-base status. Four patients required dialysis: three survived. Clinical severity scores increased from admission (mean 3.78) to TPE initiation (mean 4.44), and no patient showed improvement before TPE. Conclusion: Early initiation of TPE may be beneficial in severe leptospirosis, particularly when performed before irreversible cardiopulmonary failure. The combined use of TPE and corticosteroids may provide additional benefit by mitigating immune-mediated tissue injury. These findings support further investigation into the timing and patient selection criteria for TPE in severe leptospirosis, particularly in resource-limited settings.