Leptospirosis and acute respiratory failure: report of 34 cases

Introduction

Leptospirosis is generally found in tropical regions but it can occur in temperate regions. It is caused by all kinds of leptospiras and it is, in general, a self limited disease. However, reports of important complications as acute respiratory failure (ARF), associated or not with other organic dysfunction had increased in the last years and had been associated with a high mortality rate [1].

Objective

The goal from this paper is to evaluate the clinical characteristics and the morbimortality of severe leptospirosis associated with ARF in two general ICU from two general hospitals.

Methods

All cases with the diagnosis of leptospirosis, confirmed by blood macroagglutination test, associated with ARF and admitted from January 1990 to October 2000, in two general ICU from two general hospitals, were studied. There were analyzed the clinical and laboratory characteristics, the associated organic dysfunction and the mortality rate. Survivors were compared with non-survivors. The quantitative variables have been compared by unpaired t-test and the qualitative variables by a chi-squared test. The level of significance was P < 0.05.

Results

We described 34 adults patients, 39 ± 16 years, 28 men and 6 women. The most frequent clinical manifestation were dyspnea (n = 32), fever (n = 31), myalgias (n = 29), jaundice (n = 28), hemoptysis (n = 25) and cough (n = 25). All patients showed ARF needing for mechanical ventilation (PaO₂/FIO₂ = 169 ± 73, with diffuse pulmonary infiltrates in all cases) as well as some level of other organic dysfunction as hepatic (n = 26), renal (n = 25), cardiovascular (n = 22), hematological (n = 20) and neurological (n = 11). The mortality rate was 53% (n = 18). The comparison between non-survivors and survivors showed they were older (P < 0.05) and had: 1) higher number of organic dysfunction, principally higher incidence of renal, cardiovascular and neurological failures (P < 0.05); 2) higher levels of acidosis (P < 0.05); 3) higher use of invasive mechanical ventilation and positive end-expiratory pressure (P < 0.05).

Conclusions

In endemic regions leptospirosis has to be considered as a cause of ARF as well as a cause of other associated organic dysfunction. Leptospirosis associated with ARF has a high mortality rate mainly when associated with other organic failures.