Background: Renal involvement [as acute renal failure (ARF)] is a prominent feature of both mild and severe leptospirosis-a re-emerging infectious disease. Few large series describe in detail clinical and laboratory features of cases with ARF and their outcome.
Methods: We performed a retrospective analysis (1997-2001) of all consecutive, serological confirmed leptospirosis cases with ARF (n=58, 53 male, age 44+/-13 years, rural residents=31%, animal contact=88%.
Results: Clinical manifestations (>50% prevalence): oliguria 95%, fever and jaundice 93%, nausea and vomiting 83%, haemorrhagic diathesis 80%, headache, hepatomegaly 76%, myalgias, abdominal pain 70%, hypotension 62%, disturbed consciousness 50%. A pattern of multiple organ failure (MOF) was frequent: ARF together with hepatic failure in 72%, respiratory failure in 38%, circulatory failure in 33%, pancreatitis in 25% and rhabdomyolysis in 5% of cases. Renal dysfunction: 35% of cases had a renal K(+)-wasting defect and 43% a FE(Na)(+)>1% and low-osmolarity urine despite volume depletion. Haematuria was encountered in 12 and mild proteinuria in 10 subjects.
Outcome: 26% deaths, 64% normal hepatic and renal function at 90 days from presentation (however 29% maintained the initial tubular defect), 10% persistent mild renal failure. All deceased patients had, beside ARF, at least two other organ failures, affected consciousness, and haemorrhagic diathesis vs a prevalence for the above features of only 34, 33, and 72%, respectively, in the survivors group (P<0.05).
Conclusions: Leptospirosis presenting with ARF is a severe disease, frequently leading to MOF and to death in one-third of the patients. In particular, the haemorrhagic diathesis and cerebral involvement are markers for unfavourable patient and renal outcomes.