Mycobacterium avium complex (MAC) isolated from AIDS patients and the criteria required for its implication in disease

Before the AIDS pandemia, the Mycobacterium avium complex (MAC) was responsible in most cases for the pneumopathies that attack patients with basic chronic pulmonary diseases such as emphysema and chronic bronchitis36. In 1981, with the advent of the acquired immunodeficiency syndrome (AIDS), MAC started to represent one of the most frequent bacterial diseases among AIDS patients, with the disseminated form of the disease being the major clinical manifestation of the infection8. Between January 1989 and February 1991, the Section of Mycobacteria of the Adolfo Lutz Institute, São Paulo, isolated MAC from 103 patients by culturing different sterile and no-sterile processed specimens collected from 2304 patients seen at the AIDS Reference and Training Center and/or Emilio Ribas Infectology Institute. Disseminated disease was diagnosed in 29 of those patients on the basis of MAC isolation from blood and/or bone marrow aspirate. The other 74 patients were divided into categories highly (5), moderately (26) and little suggestive of disease (43) according to the criteria of DAVIDSON (1989)10. The various criteria for MAC isolation from sterile and non-sterile specimens are discussed.

PARACOCCIDIOIDOMYCOSIS AND AIDS: REPORT OF THE FIRST TWO COLOMBIAN CASES

The records of the first two Colombian patients with AIDS and paracoccidioidomycosis are presented. Both patients were males and had no known risk factors for HIV although in the past they had worked in the field where they could have been infected with the fungus. They exhibited the juvenile type of disease with multiple organ system involvement and symptoms of short duration. They were deeply immunodepressed as indicated by less than 100 CD4 T lymphocytes per mL; however, serologic tests revealed circulating anti-Paracoccidioides brasiliensis antibodies and in one patient the first diagnostic clue came from such tests. In one case, the mycosis preceded the AIDS diagnosis while in the other, both pathologies were discovered simultaneously. Antimycotic therapy with itraconazole was administered for over 10 months, with an initial dose of 200 mg/day followed by 100 mg/day; marked improvement of the mycotic signs and symptoms was soon noticed an there have been no signs of relapse. The patients´ improvement was also due to the combined retroviral treatment that was instituted. In spite of the rarity of the AIDS-paracoccidioidomycosis association, physicians practicing in endemic areas should consider the presence of the mycosis in immunosuppressed patients, since a prompt diagnosis and institution of combined antimycotic-anti-retroviral treatments would result in patient improvement and survival. It appears possible that the longer survival time of today's AIDS patients would give the quiescent fungus the opportunity to revive, multiply and cause overt disease.

Chagas' Disease and HIV Co-infection: Genotypic Characterization of the Trypanosoma cruzi Strain

In the past few years, new aspects of the immunopathology of Chagas' disease have been described in immunosuppressed patients, such as fatal central nervous system lesions related to the reactivation of the parasite. This article is the first description of the genotypic characterization, at the strain level, of Trypanosoma cruzi isolated from a patient with Chagas` disease/AIDS co-infection. The presence of four hypodense lesions was observed in the cranial compute tomographic scan. The diagnosis of AIDS was assessed by the detection of anti-HIV antibodies using enzyme-linked immunosorbent assay (ELISA) and Western blot techniques. The CD4+ lymphocyte counts were maintained under 200 cells/mm3 during one year demonstrating the severity of the state of immunosuppression. Chagas' disease was confirmed by serological and parasitological methods. Trypomastigote forms were visualized in a thick blood smear. The parasite isolated is genotypically similar to the CL strain. The paper reinforces that cerebral Chagas' disease can be considered as another potential opportunistic infection in AIDS resulting from the reactivation of a dormant T. cruzi infection acquired years earlier.

The AIDS epidemic in the Amazon region: a spatial case-control study in Rondonia, Brazil

OBJECTIVE To analyze spatial changes in the risk of AIDS and the relationship between AIDS incidence and socioeconomic variables in the state of Rondonia, Amazon region. METHODS A spatial, population case-control study in Rondonia, Brazil, based on 1,780 cases reported to the Epidemiological Surveillance System and controls based on demographic data from 1987 to 2006. The cases were grouped into five consecutive four-year periods. A generalized additive model was adjusted to the data; the dependent variable was the status of the individuals (case or control), and the independent variables were a bi-dimensional spline of the geographic coordinates and some municipality-level socioeconomic variables. The observed values of the Moran’s I test were compared to a reference distribution of values generated under conditions of spatial randomness. RESULTS AIDS risk shows a marked spatial and temporal pattern. The disease incidence is related to socioeconomic variables at the municipal level in Rondônia, such as urbanization and human capital. The highest incidence rates of AIDS are in municipalities along the BR-364 highway and calculations of the Moran’s I test show positive spatial correlation associated with proximity of the municipality to the highway in the third and fourth periods (p = 0.05). CONCLUSIONS Incidence of the disease is higher in municipalities of greater economic wealth and urbanization, and in those municipalities bisected by Rondônia’s main roads. The rapid development associated with the opening up of once remote regions may be accompanied by an increase in these risks to health.

Immunodiagnosis of hydatid disease: evaluation of antigens from hydatid cyst fluid and the vesicularfluid of Taenia crassiceps metacestode

The specificity and sensitivity of the enzyme immunoassay (EIA), presently used in South America areas where hydatidosis caused by Echinococcus granulosus is endemic, was compared to two alternative EIA. One of these uses an hydatid antigen of different prepraration and the other vesicular fluid of Taenia crassiceps cisticerci (VFCC). The effect of previous neutralization in the serum sample of antibodies anti-normal ovine or murine sera and anti-phosphorylcholine on the diagnostic efficiency of these EIA was studied. The frequency of distribution of the titers obtained with normal sera, hydatid sera positive to DD5 test and hydatid sera negative to DD5 test in three EIA systems was analyzed. Results showed a significant decrease of sensitivity of the EIA using VFCC when compared to these EIA using hydatid antigens. This makes inconvenient the use of VFCC for the immunodiagnosis of hydatid disease. No significant differences between the two EIA using hydatid antigens were observed. SDS-PAGE analysis showed remarkable differences between the VFCC and the hydatid antigens composition and some differences among these latters probably due to manufacturing procedures.

Plasma levels of tumor necrosis factor-alpha in patients with visceral leishmaniasis (Kala-Azar). Association with activity of the disease and clinical remisson following antimonial therapy

Evaluation of TNF-alpha in patients with Kala-azar has drawn increasing interest due to its regulatory role on the immune system, in addition to its cachetizing activity. The objective of this study was to examine the association between plasma levels of TNF-alpha, measured by immunore-activity (ELISA) and bioactivity (cytotoxicity assay with L-929 cells), and clinical manifestations of visceral leishmaniasis. Plasma samples from 19 patients with Kala-azar were obtained before, during and at the end of antimonial therapy. TNF-alpha determinations was done by using the cytotoxicity assay (all patients) and the enzyme-linked immunoassay (ELISA - 14 patients). A discrepancy between results obtained by ELISA and cytotoxicity assay was observed. Levels of circulating TNF-alpha, assessed by ELISA, were higher in patients than in healthy controls, and declined significantly with improvement in clinical and laboratory parameters. Plasma levels before treatment were 124.7 ± 93.3 pg/ml (mean ± SD) and were higher than at the end of therapy 13.9 ± 25.1 pg/ml (mean ± SD) (p = 0.001). In contrast, plasma levels of TNF-alpha evaluated by cytotoxicity assay did not follow a predicted course during follow-up. Lysis, in this case, might be not totally attributed to TNF-alpha. The discrepancy might be attributed to the presence of factor(s) known to influence the release and activity of TNF-alpha.

Peptic disease and Helicobacter pylori are highly prevalent in patients with the indeterminate form of chagas’ disease: report of 21 cases

Given that chagasic patients in the indeterminate form of this disease, can have abnormal motility of the digestive tract and immunologic abnormalities, we decided to assess the frequency of peptic disease and Helicobacter pylori (Hp) infection in these individuals. Twenty-one individuals, 13 males and 8 females, mean age 37.6 ± 11.1 years, were examined. Biopsies of the duodenum, antrum, lesser and greater gastric curvature and esophagus were performed. The endoscopic findings were of chronic gastritis in 20 (95.2%) patients, duodenal ulcer in 3 (14.3%), gastric and duodenal ulcer in 3 (14.3%), gastric ulcer alone in 1 (4.8%), esophagitis in 5 (23.8%), and duodenitis in 5 (23.8%). The diagnosis of infection by the Hp was done by the urease test and histologic examination. Hp infection was found in 20 (95.2%) individuals: in 20 out of them in the antrum, in 17 in the lesser curvature, and in 17 in the greater curvature. Hp was not found in the esophagus and duodenum. The only individual with no evidence of infection by Hp was also the only one with normal endoscopic and histologic examinations. The histologic examinations confirmed the diagnoses of gastric ulcer as peptic, chronic gastritis in 20 patients, duodenitis in 14, and esophagitis in 9. In this series the patients had a high frequency of peptic disease, which was closely associated with Hp infection

Antiretroviral treatment for HIV infection/AIDS and the risk of developing hyperglycemia and hyperlipidemia

A cross-sectional study with internal comparison groups was conducted to describe sociodemographic characteristics, as well as verify the association between the type of antiretroviral treatment used and hyperglycemia and hyperlipidemia, with special attention to the use of HIV protease inhibitors. The data was obtained through an interview questionnaire, as well as blood and urine samples that were collected for the laboratory exams. A total of 418 patients were interviewed. 46 of these, however, met the exclusion criteria. The sample was therefore composed by 372 HIV positive patients, attended at the laboratory of the Correia Picanço State Hospital for the collection of blood, to estimate the HIV viral load and/or TCD4 cell counts from August to November 2000. The association between the variables was tested using the chi-square test and the p-value. A multiple logistic regression analysis was carried out to adjust for potential confounding factors. A greater frequency of patients with high glucose levels was observed among those making use of antiretroviral therapy without protease inhibitors, but the number of patients limited the comparisons. An association was verified between the total serum cholesterol level and the use of HIV protease inhibitors (p = 0.047) even after controlling for age. An association was also observed between the triglyceride levels and the use of HIV protease inhibitors, which remained after adjustment for age, sex and creatinine levels (p < 0.001). The levels of glucose and TSH, the presence of proteinuria and the practice of physical activity were not associated either with the levels of cholesterol or with the levels of tryglicerides thus they were not confounders of the associations described.

Evaluation of seroepidemiological toxoplasmosis in HIV/AIDS patients in the south of Brazil

Toxoplasmosis is considered one of the opportunistic infections for individuals with the Acquired Immunodeficiency Syndrome (AIDS), and is also a major cause of morbidity and mortality. The aim of this study was to evaluate the prevalence of neurotoxoplasmosis, ocular toxoplasmosis and antibodies for Toxoplasma gondii in HIV-positive patients attending the SAE (Specialized Assistance Service for HIV/AIDS), as well as to associate their serological profile with epidemiological and clinical data. A total of 250 patients participated in the study from December, 2009 to November, 2010. Serological analysis was performed using the indirect immunofluorescent technique; epidemiological data were gathered by a questionnaire, and clinical history was based on the analysis of medical charts. Prevalence of seropositivity was 80%, with history of neurotoxoplasmosis in 4.8% and of ocular toxoplasmosis in 1.6% of the patients. The Highly Active Antiretroviral Treatment (HAART) was not used by 32% of the patients, 18.4% of the patients had CD4+ T- lymphocyte count less than 200 cells/mm³ and 96.8% of them were not aware of the modes of disease transmission. These findings led us to conclude that the study population is at high risk of clinical toxoplasmosis, because of both reactivation of infection in the seropositive patients who do not make a regular use of HAART, and primo-infection in seronegative patients worsened by an unawareness of the modes of infection reported in this study.

THE PROCESS OF Leishmania INFECTION - DISEASE AND NEW PERSPECTIVES OF PALEOPARASITOLOGY

Species of the genus Leishmania (Kinetoplastida, Trypanosomatidae) are causative agents of leishmaniasis, a complex disease with variable clinical spectrum and epidemiological diversity, constituting, in some countries, a serious public health problem. The origin and evolution of leishmaniasis has been under discussion regarding some clinical and parasitological aspects. After the introduction of paleoparasitology, molecular methods and immunodiagnostic techniques have been applied allowing the recovery of parasite remains, as well as the diagnosis of past infections in humans and other hosts. The dating of archaeological samples has allowed the parasitological analysis in time and space. This manuscript presents the state of the art of leishmaniasis and prospects related to paleoparasitology studies and their contribution to the evolutionary and phylogenetic clarification of parasites belonging to the genus Leishmania, and the leishmaniasis caused by them.