What complications can patients with leptospirosis experience?

Complications of Leptospirosis

Leptospirosis can progress from a mild flu-like illness to life-threatening multi-organ failure, with severe disease (Weil's disease) occurring in 5-10% of infected patients and carrying a mortality rate exceeding 50% even with intensive care support. The most critical complications include acute renal failure, severe pulmonary hemorrhage syndrome, hepatic dysfunction with jaundice, and multi-organ dysfunction syndrome, all of which require immediate recognition and aggressive supportive care. 1, 2, 3

Renal Complications

Acute renal failure is one of the most common and serious complications of leptospirosis, presenting in both oliguric and nonoliguric forms. 2, 3

• Nonoliguric (high output) renal dysfunction should be managed with aggressive fluid and electrolyte replacement 3
• Oliguric renal failure requires prompt initiation of dialysis, which can be life-saving 3
• Proteinuria and hematuria are early laboratory indicators of renal involvement 2
• Renal dysfunction can progress rapidly and requires continuous monitoring with serial renal function tests 2, 4

Pulmonary Complications

Pulmonary involvement occurs in 20-70% of patients, with severe pulmonary hemorrhage syndrome representing the most lethal complication. 5, 3

• Severe pulmonary hemorrhage syndrome due to extensive alveolar hemorrhage has a fatality rate exceeding 50% 3
• Patients may present with bloody sputum, dyspnea, and rapidly progressive respiratory distress requiring mechanical ventilation 6, 7
• Acute respiratory distress syndrome (ARDS) can develop as part of multi-organ dysfunction 6
• Pulmonary manifestations can occur even in anicteric cases without jaundice 4

Hepatic Complications

Hepatic involvement manifests as jaundice with characteristic laboratory patterns that distinguish leptospirosis from viral hepatitis. 2, 3

• Elevated bilirubin with only mild elevation of transaminases is the typical pattern 2
• Hepatocellular damage and disruption of intercellular junctions between hepatocytes cause bilirubin leakage from bile canaliculi 3
• Jaundice is a hallmark of severe leptospirosis (Weil's disease) and indicates poor prognosis 1, 2
• Leptospirosis may be misdiagnosed as viral hepatitis in patients presenting with fever and jaundice, delaying appropriate treatment 2

Hematologic Complications

Hemorrhagic complications are common in severe leptospirosis and are associated with coagulation abnormalities and thrombocytopenia. 3, 4

• Thrombocytopenia is a frequent finding in both icteric and anicteric forms 4
• Anemia can occur if there is significant hemorrhage 2
• Coagulation abnormalities contribute to bleeding manifestations 3
• Leukocytosis with polymorphonuclear predominance is typical 2

Neurologic Complications

Neurologic involvement ranges from aseptic meningitis to rare but devastating cerebral infarction. 1, 2, 7

• Aseptic meningitis is an immune-mediated complication occurring during the secondary immune phase 5, 4
• Cerebral arteritis can lead to cerebral infarction, though this is rarely reported 7
• Cerebral occlusion, although rare, can be rapidly fatal even with appropriate antibiotic therapy 7
• Headache is nearly universal during the septicemic phase 1, 2

Musculoskeletal Complications

While myalgias are ubiquitous in leptospirosis, life-threatening rhabdomyolysis represents a rare but catastrophic complication. 6

• Massive rhabdomyolysis can occur with rapidly progressive muscle breakdown 6
• Most patients show only mildly elevated muscle enzymes, but severe cases require major life support 6
• Diffuse myalgias, especially in the calves, are characteristic of the septicemic phase 2
• Rhabdomyolysis can contribute to acute renal failure and multi-organ dysfunction 6

Multi-Organ Dysfunction Syndrome

A small proportion of patients develop shock and multi-organ dysfunction syndrome, representing the most severe form of leptospirosis. 6, 3

• Multiple organ dysfunction can occur with widespread hematogenous dissemination of pathogens 3
• Patients may require mechanical ventilation, hemodialysis, and continuous renal replacement therapy 6, 7
• Circulatory collapse can occur, particularly in association with Weil's disease 5
• High levels of bacteremia are associated with poor clinical outcomes 3

Cardiovascular Complications

Cardiac involvement can occur, though it is less commonly reported than other organ complications. 7

• Coronary artery damage has been documented in severe cases 7
• Myocarditis can contribute to circulatory collapse 5

Ocular Complications

Uveitis is an immune-mediated complication occurring during the secondary phase of illness. 5

• Uveitis develops after leptospires disappear from the blood, mediated by circulating antibodies 5

Critical Pitfalls to Avoid

• Do not delay antibiotic treatment while waiting for laboratory confirmation in suspected severe cases, as mortality increases significantly with delayed treatment 2
• Consider leptospirosis in patients with cryptogenic sepsis and multi-organ dysfunction, especially with rhabdomyolysis, as this atypical presentation can be missed 6
• Recognize that anicteric leptospirosis can still cause severe complications including renal failure and thrombocytopenia, avoiding the misconception that absence of jaundice indicates mild disease 4
• Monitor closely for fluid overload during resuscitation by watching for development of crepitations, as patients can develop impaired cardiac function 2