This study was conducted to investigate factors associated with thrombocytopenia in a large cohort of patients with leptospirosis in an endemic area. This retrospective study included 374 consecutive patients with leptospirosis who were admitted to tertiary hospitals in Fortaleza, Brazil. All patients had a diagnosis of severe leptospirosis (Weil's disease). Acute kidney injury was defined according to the RIFLE criteria. Thrombocytopenia was defined as a platelet count <100,000/mm3. A total of 374 patients were included, with a mean age of 36.1 ± 15.5 years, and 83.4% were male. Thrombocytopenia was present at the time of hospital admission in 200 cases (53.5%), and it developed during the hospital stay in 150 cases (40.3%). The patients with thrombocytopenia had higher frequencies of dehydration (53% vs. 35.3%, p=0.001), epistaxis (5.7% vs. 0.8%, p=0.033), hematemesis (13% vs. 4.6%, p=0.006), myalgia (91.5% vs. 84.5%, p=0.038), hematuria (54.8% vs. 37.6%, p=0.011), metabolic acidosis (18% vs. 9.2%, p=0.016) and hypoalbuminemia (17.8% vs. 7.5%, p=0.005). The independent risk factors associated with thrombocytopenia during the hospital stay were lengthy disease (OR: 1.2, p=0.001) and acute kidney injury (OR: 6.6, p=0.004). Mortality was not associated with thrombocytopenia at admission (12.5% vs. 12.6%, p=1.000) or during the hospital stay (12.6% vs. 11.3%, p=0.748). Thrombocytopenia is a frequent complication in leptospirosis, and this condition was present in more than half of patients at the time of hospital admission. Lengthy disease and acute kidney injury are risk factors for thrombocytopenia. There was no significant association between thrombocytopenia and mortality.

Leprosy is a chronic disease caused by Mycobacterium leprae, highly incapacitating, and with systemic involvement in some cases. Renal involvement has been reported in all forms of the disease, and it is more frequent in multibacillary forms. The clinical presentation is variable and is determined by the host immunologic system reaction to the bacilli. During the course of the disease there are the so called reactional states, in which the immune system reacts against the bacilli, exacerbating the clinical manifestations. Different renal lesions have been described in leprosy, including acute and chronic glomerulonephritis, interstitial nephritis, secondary amyloidosis and pyelonephritis. The exact mechanism that leads to glomerulonephritis in leprosy is not completely understood. Leprosy treatment includes rifampicin, dapsone and clofazimine. Prednisone and non-steroidal anti-inflammatory drugs may be used to control acute immunological episodes.

Dengue is the most important arboviral disease worldwide. Dengue diagnosis is usually made by serology, but serological techniques do not identify the infecting strain, and are only useful late in the course of infection. Several reverse transcription-polymerase chain reaction (RT-PCR) protocols have been described for dengue diagnosis but none of them has been used on a regular basis. We conducted a validation study of PCR-based diagnosis in an area (in Brazil) where dengue-1 virus has been circulating at a low incidence rate. Viral detection by RT-PCR was evaluated using the sera of 253 patients with clinical diagnosis of dengue, and the results were compared to those obtained by IgM capture enzyme-linked immunosorbent assay (MAC-ELISA) and virus isolation. Out of 75 IgM-positive samples, 17 were RT-PCR positive, and only 2 were positive for virus isolation. Through enzymatic digestion of PCR amplicons, we were able to differentiate the 2 dengue serotypes circulating in Brazil (dengue-1 and dengue-2), and to determine that dengue-1 was the virus responsible for the infections. We show with this study that RT-PCR is more sensitive than virus isolation on clinical samples and allows for a rapid detection of dengue infections and for a straightforward identification of the circulating serotype.

Chikungunya virus (CHIKV) infection is a current public health problem. The aim of this study was to investigate risk factors for death among patients with CHIKV infection during a large epidemic in northeast Brazil. This is a cross-sectional study with all registered cases of CHIKV in Ceara, Brazil, during 2016-2017. Data from notification reports were collected, and we have compared non-survivors and survivors. A total of 182 731 cases were reported, with a mean age of 38±19 years, and the majority was female (62%). There were 383 deaths. Non-survivors were elderly, with a predominance of males, and with a lower educational level. Conditions that were significantly more frequent in the non-survivor group were systemic arterial hypertension, diabetes mellitus and chronic kidney disease (p<0.0001). Independent risk factors for death were advanced age (OR 7.35, p<0.0001), male gender (OR 2.05, p<0.0001), leukopenia (OR 3.18, p<0.0001) and vomiting (OR 2.19, p<0.0001), and comorbidities like hypertension (OR 3.74, p<0.0001), diabetes (OR 3.29, p<0.0001) and chronic kidney disease (OR 3.14, p<0.0001). Advanced age and low educational level were associated with higher risk of mortality in CHIKV. Leukopenia and vomiting were signs of severity, as well as the presence of comorbidities, especially hypertension, diabetes and kidney disease.

The northeastern region of Brazil has faced in the last 2 years the largest outbreak of chikungunya virus (CHIKV) infection in its history. There are still few studies on kidney involvement in CHIKV. The aim of this study is to describe the impact of chronic kidney disease (CKD) on CHIKV clinical manifestations and outcome. This is a cross-sectional study conducted in the State of Ceara, northeastern Brazil, including all registered cases of CHIKV infection in the period from January 2016 to December 2017. Clinical manifestations were collected from the notification reports from official data bank from the State Secretary of Health of Ceara: National System of Diseases Notification and Laboratory Manager. A total of 182,731 cases were notified. Patients’ mean age was 32.4 ± 14.6 years, and 62.2% were female. The most common clinical manifestations were fever (88.6%), headache (72.9%), intense arthralgia (69.5%), and myalgia (65.6%). Hospital admission was required for 3,080 cases (3.3%), and death occurred in 383 cases (0.2%). Chronic kidney disease was reported in 691 cases (0.3%). Patients with CKD had a higher frequency of almost all clinical manifestations, including fever, myalgia, exanthema, vomiting, nausea, back pain, conjunctivitis, arthritis, severe arthralgia, petechiae, and retro-orbital pain. They also had a significantly higher frequency of diabetes, hematological disorders, liver diseases, hypertension, peptic ulcer disease, and autoimmune diseases. Mortality was significantly higher among CKD patients than patients without CKD (3.0% versus 0.2%, P < 0.0001).

Infection with both Human Immunodeficiency Virus (HIV) and Mycobacterium tuberculosis is currently the world's leading cause of death due to infectious agents. We evaluated factors related to the development of tuberculosis (TB) in HIV-infected patients who were being treated at an infectious diseases hospital in Fortaleza, Ceará, Brazil. From January 2004 to December 2005, we made an epidemiological study through the analysis of the medical records of 171 patients, who were diagnosed as having both HIV and tuberculosis. Among these co-infected patients, most (81%, p=0.0006) were male. Co-infection was more frequent (87.8%) among patients over 40 years of age and those with lower educational levels (less than eight years of schooling). Forty-one percent of the patients in the study had not had a smear culture test for acid-fast bacilli (AFB). CD4 cell counts were lower than 200 cells/µL in 71.9% of the patients, the mean being 169 cells/µL. This type of data is important for establishing strategies to improve the control of tuberculosis in HIV-infected patients.