Potential Differential Marker in the Diagnosis of Leptospirosis

Abstract

Human leptospirosis, or commonly known as the “rat urine disease” is a zoonotic disease caused by a bacterium called Leptospira sp. acquired via the urine of animal carriers. It is believed that the incidence rate of leptospirosis has been under-reported due to its unspecific clinical Symptoms and the limitations of current diagnostic methods. Leptospirosis can be effectively treated with antibiotics in the early stage, and it is a curable disease. But the accuracy to diagnose the infection is rarely achieved. The present study investigated the plasma protein profiles of lleptospirosis patients who presented with different clinical presentations, and compared them against two control groups consisting of dengue patients and healthy individuals. The plasma protein digests were analyzed using a shotgun approach by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as described by the manufacturer. The proteins detected in every leptospirosis patient and with at least two-fold differential expression with statistical significance (p<0.05) compared to the control groups were identified. Lipopolysaccharide (LPS)-binding protein (LBP) is reported as the only plasma protein that fulfilled the selection criteria. The characteristics and roles of LBP in the immune system during infections are reviewed. Compared to the other proteome-based studies on human leptospirosis. The present study is the first that reported LBP as one of the significant differentially expressed proteins. Potential of coupling LBP with other disease-specific biomarkers in clinical diagnosisand prognosis should be considered.