Pathology and pathogenesis of human leptospirosis: a commented review

Abstract

Leptospirosis is an acute bacterial septicemic febrile disease caused by pathogenic leptospires, which affect humans and animals in all parts of the world. Transmission can occur by direct contact with infected animals or, more commonly, through indirect contact with water or soil contaminated with urine from infected animals. Leptospires enter the body by penetrating mucous membranes or skin abrasions and disseminate through the hematogenic route. In humans, leptospirosis may cause a wide spectrum of symptoms. Most cases have a biphasic clinical presentation, which begins with the septicemic phase followed by immune manifestations. The severe forms of the disease may be life threatening with multisystem damage including renal failure, hepatic dysfunction, vascular damage, pulmonary hemorrhage and muscle lesions. In this review, we present and discuss the pathogenesis of the human disease and the mechanisms of cell membrane injuries, which occur mainly due to the presence of leptospires and/or their antigen/s in the host tissues.

Leptospirosis as an unusual culprit of acute pancreatitis and portal vein thrombosis in a New Yorker

“…Leptospira antigens present in muscle sarcoplasm during active infection, creating an immunological target that produces myositis and elevated creatinine kinase. 2 Resultant myoglobinuria may also contribute to renal failure, but this conjecture requires further study. 18 Leptospirosis is underdiagnosed because physicians lack clinical suspicion, symptomatology varies, reporting systems are poor, and serological testing is usually expensive and time-consuming.…”

“…Rhabdomyolysis in this patient is also characteristic of leptospirosis. Leptospira antigens present in muscle sarcoplasm during active infection, creating an immunological target that produces myositis and elevated creatinine kinase . Resultant myoglobinuria may also contribute to renal failure, but this conjecture requires further study …”

“…Humans can remain asymptomatic and disseminate Leptospira into the environment for up to 1 year. 2 Leptospirosis is common to an array of tropical climates but also poses a risk to low socioeconomic populations in city areas. [5][6][7] Among symptomatic patients, one study suggests that the mortality rate for untreated leptospirosis ranges between 0% and 40% (median 2.2%).…”

“…Based on a systematic review of published mortality and morbidity studies, it is estimated the global burden of leptospirosis is 1.03 million cases each year . While disease manifestation may be mild or asymptomatic, severe disease can present with multiorgan dysfunction including liver failure, renal failure, pulmonary hemorrhage, vascular damage, and muscle lesions . One of the classic manifestations of leptospirosis is Weil's disease—the combination of hemorrhagic events, jaundice, and acute renal failure—first observed by Adolf Weil in 1886 .…”

“…1 While disease manifestation may be mild or asymptomatic, severe disease can present with multiorgan dysfunction including liver failure, renal failure, pulmonary hemorrhage, vascular damage, and muscle lesions. 2 One of the classic manifestations of leptospirosis is Weil's disease-the combination of hemorrhagic events, jaundice, and acute renal failure-first observed by Adolf Weil in 1886. 3 We present a case of a 61-year-old homeless New Yorker complaining of abdominal pain who was found to have acute pancreatitis, myositis, and portal vein thrombosis due to leptospirosis in addition to renal failure and hepatic dysfunction.…”