Pathogenesis of Pulmonary Hemorrhagic Syndrome in Human Leptospirosis.

Based on a previous study and by incorporating new knowledge, the goal of our study was to understand more fully the pathogenesis of hemorrhagic pneumonia of severe human leptospirosis, highlighting the onset of capillary lesions by Leptospira itself and/or its antigenic/toxic products acting on the endothelium and binding to cadherins. Both events lead to loss of endothelial integrity, alter permeability, cause rupture, and open intercellular junctions, contributing to the hemorrhagic phenomena associated with severe leptospirosis.

Disease Severity Prediction by Spirometry in Adults with Visceral Leishmaniasis from Minas Gerais, Brazil.

Visceral leishmaniasis (VL) is associated with interstitial pneumonitis according to histology and radiology reports. However, studies to address the functional impact on respiratory function in patients are lacking. We assessed pulmonary function using noninvasive spirometry in a cross-sectional study of hospitalized adult VL patients from Minas Gerais, Brazil, without unrelated lung conditions or acute infections. Lung conditions were graded as normal, restrictive, obstructive, or mixed patterns, according to Brazilian consensus standards for spirometry. To control for regional patterns of lung function, we compared spirometry of patients with regional paired controls. Spirometry detected abnormal lung function in most VL patients (70%, 14/20), usually showing a restrictive pattern, in contrast to regional controls and the standards for normal tests. Alterations in spirometry measurements correlated with hypoalbuminemia, the only laboratory value indicative of severity of parasitic disease. Abnormalities did not correlate with unrelated factors such as smoking or occupation. Clinical data including pulmonary symptoms and duration of therapy were also unrelated to abnormal spirometry findings. We conclude that the severity of VL is correlated with a restrictive pattern of lung function according to spirometry, suggesting that there may be interstitial lung involvement in VL. Further studies should address whether spirometry could serve as an index of disease severity in the management of VL.

Facial structure alterations and abnormalities of the paranasal sinuses on multidetector computed tomography scans of patients with treated mucosal leishmaniasis.

BACKGROUND/OBJECTIVES: Mucosal leishmaniasis (ML) is a progressive disease that affects cartilage and bone structures of the nose and other upper respiratory tract structures. Complications associated with ML have been described, but there is a lack of studies that evaluate the structural changes of the nose and paranasal sinuses in ML using radiological methods. In this study, we aimed to assess the opacification of the paranasal sinuses in patients with treated ML and any anatomical changes in the face associated with ML using multidetector computed tomography scans (MDCT) of the sinuses. We compared the findings with a control group. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated 54 patients with treated ML who underwent CT scans of the sinuses and compared them with a control group of 40 patients who underwent orbital CT scans. The degree of sinus disease was assessed according to the Lund-Mackay criteria. Forty of the 54 patients with a history of ML (74.1%) had a tomographic score compatible with chronic sinusitis (Lund-Mackay ≥4). CT scans in the leishmaniasis and control groups demonstrated significant differences in terms of facial structure alterations. Patients from the ML group showed more severe levels of partial opacification and pansinus mucosal thickening (42.6%) and a greater severity of total opacification. Patients from the ML group with a Lund-Mackay score ≥4 presented longer durations of disease before treatment and more severe presentations of the disease at diagnosis. CONCLUSION/SIGNIFICANCE: CT scans of the sinuses of patients with ML presented several structural alterations, revealing a prominent destructive feature of the disease. The higher prevalence in this study of chronic rhinosinusitis observed in CT scans of patients with treated ML than in those of the control group suggests that ML can be considered a risk factor for chronic rhinosinusitis in this population (p<0.05).

Are the severe injuries of cutaneous leishmaniasis caused by an exacerbated Th1 response?

American tegumentary leishmaniasis (ATL) is a disease whose clinical features are strongly related to the type of immune response it induces. Herein we report an atypical presentation of cutaneous leishmaniasis in a woman with a severe and extensive sore located in her leg, and we describe the differences between the usual local immune response in ATL and the local immune response in this patient. We observed an intense inflammatory response characterized by Th1 cells and cytokines with conspicuous expression of Toll-like receptor 3 (TLR-3). Few parasites were present, but there was an extensive tissue damage. We also discuss the immunological factors that could be related to the atypical presentation.

Can we use a lower dose of liposomal amphotericin B for the treatment of mucosal American leishmaniasis?

Liposomal amphotericin B has been used as an alternative treatment of mucosal leishmaniasis, but the optimal dose is not established. We retrospectively reviewed the clinical outcome of eight patients with mucosal leishmaniasis treated with liposomal amphotericin B. The mean total dose was 35 mg/kg (range 24-50 mg/kg), which resulted in the healing of all the lesions in all patients and no recurrences were observed during the follow-up period (mean 25 months; range 7-40 months).

Mucosal leishmaniasis and abnormalities on computed tomographic scans of paranasal sinuses.

Studies evaluating radiologic aspects, local complications, and structural alterations of the paranasal sinus in patients with mucosal leishmaniasis (ML) are lacking. The aim of this study was to analyze alterations of the paranasal sinuses in patients with ML by using computed tomography (CT) scans. This prospective study evaluated 26 patients in Brazil with ML from December 2008 through June 2009. All patients underwent CT scans of the paranasal sinuses. Paranasal thickening was observed in 25 patients (96%). Nasal perforation was observed in 17 patients (65%). Those patients who received re-treatment showed more abnormalities on CT scan than cured patients (P < 0.05). Complications of ML are not limited to the nasal mucosa but extend to the paranasal sinuses. Mucosal thickening, opacified air cells, bony remodeling, and bony thickening caused by inflammatory osteitis of the sinus cavity walls are CT findings suggestive of chronic sinusitis.

Antimicrobial therapy for community-acquired pneumonia in adults.

This is part of the series of practice guidelines commissioned by the Brazilian Society for Infectious Diseases through its Practice Guidelines Committee. The purpose of these guidelines is to provide assistance to clinicians in the antimicrobial treatment of community-acquired pneumonia (CAP) in immunocompetent adults. Panel members and consultants are experts in adult infectious diseases. The guidelines are evidence based where possible. The recommendations included in this document were elaborated based on the most frequently isolated pathogens and their antimicrobial susceptibilities. The etiology was based mainly on international studies, since there are very few regional data. On the other hand, the antimicrobial susceptibilities of main bacterial causes of CAP were based on the results of several antimicrobial resistance surveillance studies recently performed in Brazil. Other reference guidelines for the treatment of CAP, such as those elaborated by the Infectious Diseases Society of America and by the Canadian Infectious Diseases Society, were also discussed by the group during the elaboration of this document.

Antimicrobial therapy for community-acquired pneumonia in adults

This is part of the series of practice guidelines commissioned by the Brazilian Society for Infectious Diseases through its Practice Guidelines Committee. The purpose of these guidelines is to provide assistance to clinicians in the antimicrobial treatment of community-acquired pneumonia (CAP) in immunocompetent adults. Panel members and consultants are experts in adult infectious diseases. The guidelines are evidence based where possible. The recommendations included in this document were elaborated based on the most frequently isolated pathogens and their antimicrobial susceptibilities. The etiology was based mainly on international studies, since there are very few regional data. On the other hand, the antimicrobial susceptibilities of main bacterial causes of CAP were based on the results of several antimicrobial resistance surveillance studies recently performed in Brazil. Other reference guidelines for the treatment of CAP, such as those elaborated by the Infectious Diseases Society of America and by the Canadian Infectious Diseases Society, were also discussed by the group during the elaboration of this document.