The secretory immunoglobulin A response to Mycobacterium tuberculosis in a childhood population

We report on the measurement of saliva anti-Purified Protein Derivative sIgA and 38kDa antibodies from 127 children, of whom 31 were strong tuberculosis suspects and 96 were healthy contact children. The results concerning the percentage of children with antibody reactivity to PPD and 38kDa antigens showed that, of these 2 antigens, 38kDa induced higher reactivity in patients positive and negative for the Tuberculin Skin Test (28% and 16.6%, respectively) in comparison to controls positive and negative for the TST (11.7% and 7.1%, respectively). There was a statistically significant difference between patients positive and controls negative for the TST. In relation to the Purified Protein Derivative antigen, while 14.2% of patients positive for the TST showed antibody reactivity to the PPD antigen, no patients negative for the TST had reactivity to this antigen. The findings suggest that these two antigens seem be associated with a different development of the mucosal defence mechanisms mediated by sIgA against Mycobacterium tuberculosis.

Clinical, epidemiological and laboratory aspects of patients with American cutaneous leishmaniasis in the State of Pernambuco

The diagnosis for American cutaneous leishmaniasis is based on an association of clinical, epidemiological and laboratory characteristics. The present study identified the circulating species of Leishmania in the State of Pernambuco, described its clinical-epidemiological characteristics and diagnosed the disease. Nineteen patients presenting active lesions who had been diagnosed through clinical evaluation and laboratory tests were selected. The tests included direct investigation, in vitro culturing, Montenegro skin test, indirect immunofluorescence and polymerase chain reaction. The Montenegro Skin Test showed positive results in 89% of the patients; indirect immunofluorescence, in 79%; direct investigation, in 58%; and polymerase chain reaction in 75%. Seven Leishmania (Viannia) braziliensis samples were isolated from these patients and were characterized by means of specific monoclonal antibodies. These data confirm that a combination of different diagnosis techniques is needed in order to obtain efficient results and that, so far, Leishmania (Viannia) braziliensis is the only species responsible for American cutaneous leishmaniasis infection in Pernambuco. Thus, it is essential to identify the parasite species involved in cases of human disease in an endemic area in order to determine the clinical and epidemiological characteristics, especially with regard to diagnosis, therapy development and disease prognosis.

Risk factors for Leishmania chagasi infection in an endemic area in Raposa, State of Maranhão, Brazil

INTRODUCTION: Infection with Leishmania chagasi is the most common clinical presentation for visceral leishmaniaisis in endemic areas. The municipality of Raposa is an endemic area in State of Maranhão, Brazil, and have had registration cases of visceral leishmaniasis disease. For this reason, a cross- sectional study was conducted to evaluate the risk factors for infection with L. chagasi detected by Montenegro skin test. METHODS: The sample comprised 96% of the inhabitants of the villages of Maresia, Pantoja, and Marisol located in the municipality of Raposa, corresponding to 1,359 subjects. Data were collected using a questionnaire. Univariate and multivariate logistic regression models were applied to evaluate the association between the variables studied and infection of L. chagasi. RESULTS: The variables associated with infection upon nonadjusted analysis were a straw roof, mud walls, floors of beaten earth, presence of sand flies inside or outside of the dwelling, and bathing outdoors. Adjusted analysis showed that the presence of sand flies inside/outside the dwelling was a risk factor, and age younger than 10 years was a protective factor against asymptomatic infection. CONCLUSIONS: The results highlight the extent to which precarious living conditions of the population strengthen the epidemiological chain of visceral leishmaniasis.

Active surveillance of American tegumentary leishmaniasis in endemic areas in rural Bolivia

INTRODUCTION: American tegumentary leishmaniasis (ATL), including mucocutaneous leishmaniasis (MCL) and localized cutaneous leishmaniasis (LCL), is endemic in Bolivia. We describe the results of active surveillance of ATL from 2001 to 2006 and assess demographic data related to ATL epidemiology in the Yungas valleys. METHODS: Community-based active ATL surveillance was performed by the institutions SERVIR, CÁRITAS, and the Health Services Department of La Paz, whose files were reviewed retrospectively. A cross-sectional survey was carried out to assess demographic data in two communities. RESULTS: Two thousand nine hundred nine cases of ATL were detected from 2001 to 2006: 2,488 (85.5%) corresponded to LCL and 421 (14.5%) to MCL. A reduction in the proportion of mucosal cases was observed between 2001 and 2006. The proportion of MCL cases increased with age and was higher among males (15.5% versus 12.1%, p=0.018). The rate of positivity via direct observation of the parasite in dermal scrapings and in parasite cultivation was significantly higher for LCL than for MCL (p<0.001 and p=0.009, respectively). The rate of reactivity in the leishmanin skin test was higher in the group with mucosal lesions (p=0.012). The cross-sectional survey showed that 40% of the families had emigrated from the Altiplano. CONCLUSIONS: It is necessary to undertake continuous case detection of ATL in the area, where the disease presents a high rate of mucosal cases. Increasing incidence seems to be associated with immigration and continuous deforestation to expand the crop-growing areas.

Geographic analysis on the occurrence of human and canine leptospirosis in the city of Maringá, state of Paraná, Brazil

INTRODUCTION: Leptospirosis is a zoonotic disease, the primary hosts of which are wild, synanthropic, and household animals. Humans behave as terminal and accidental hosts. The prevalence of leptospirosis depends on carrier animals that disseminate the agent, on the environmental survival of this agent, and on the contact of susceptible individuals. Each serovar has one or more hosts with different adaptation levels. The focuses of leptospirosis are infected, sick, and asymptomatic animals, which are considered to be sources of environmental infection. This study aimed to determine the risk areas for leptospiral infection in stray dogs and patients diagnosed with leptospirosis from 2006 to 2008 in Maringá, State of Paraná, Brazil. METHODS: Three hundred and thirty-five stray dogs and 25 patients were studied. Serum from both animals and patients was examined by the microscopic serum agglutination test to study anti-leptospiral antibodies. To determine the risk areas and the spatial distribution of the disease, thematic maps were designed. RESULTS: Forty-one (12.2%) dogs positive for one or more leptospire serovars were observed, the most frequent serovars being Pyrogenes (43.9%), Canícola (21.9%), and Copennhageni (19.5%). Among the humans, 2 (8%) were positive for serovars Pyrogenes and Hardjo Prajitno and for Pyrogenes and Cynopteri. CONCLUSIONS: Spatial analysis showed that the risk for dogs and humans in the City of Maringá to become infected with leptospires exists in both the central and the peripheral areas, a fact that reinforces the relevance of this study and of continuous epidemiological and environmental surveillance actions to control the disease in animals and in humans.

Prevalence of latent tuberculosis and treatment adherence among patients with chronic kidney disease in Campo Grande, State of Mato Grosso do Sul

Introduction The primary strategy for tuberculosis control involves identifying individuals with latent tuberculosis. This study aimed to estimate the prevalence of latent tuberculosis in chronic kidney disease (CKD) patients who were undergoing hemodialysis in Campo Grande, State of Mato Grosso do Sul, Brazil, to characterize the sociodemographic and clinical profiles of patients with latent tuberculosis, to verify the association between sociodemographic and clinical characteristics and the occurrence of latent tuberculosis, and to monitor patient adherence to latent tuberculosis treatment. Methods This epidemiological study involved 418 CKD patients who were undergoing hemodialysis and who underwent a tuberculin skin test. Results The prevalence of latent tuberculosis was 10.3%. The mean patient age was 53.43±14.97 years, and the patients were predominantly men (63.9%). The population was primarily Caucasian (58.6%); half (50%) were married, and 49.8% had incomplete primary educations. Previous contact with tuberculosis patients was reported by 80% of the participants. Treatment adherence was 97.7%. Conclusions We conclude that the prevalence of latent tuberculosis in our study population was low. Previous contact with patients with active tuberculosis increased the occurrence of latent infection. Although treatment adherence was high in this study, it is crucial to monitor tuberculosis treatment administered to patients in health services to maintain this high rate.

Osteoarticular tuberculosis in an HIV-positive patient: a case report

The authors report a case of a 38-year-old HIV-positive woman, with subcutaneous nodules on the thoracic region with 3 months of evolution. Clinical, laboratory, and epidemiological features were evaluated and associated with apparent damage to the T11-T12 vertebrae, identification by imaging tests, positivity in a polymerase chain reaction-based test, and reactivity to the Mantoux tuberculin skin test (PPD-RT 23). The patient was diagnosed with osteoarticular tuberculosis and received treatment for a year, and clinical cure was achieved.

An outbreak of human Leishmania (Viannia) braziliensis infection

The occurence of acute cutaneous leishmaniasis among inhabitants of 10 farms within 10 Km of the hamlet of Corte de Pedra, Bahia, Brazil was studied prospectively from 1984-l989. A mean population of 1,056 inhabitants living in 146 houses were visited every 6 months and the number of sKin ulcers recorded. A leishmanin skin test survey was done people with suggestive skin scars or active disease in l984. The incidence of skin ulcers due to Leishmania (Viannia) brasiliensis (Vlb) reached 83/1,000 inhabitants but declined sharply in the subsequent 2 years. Retrospective data shows that leishamiasis is a sporadic endemic disease. Although the reasons for this epidemic are unclear some possible aetiological factors are discussed.

Schistosomiasis mansoni in three localities of western lowland of the state of Maranhão before and after mass treatments

A cross-sectional study for schistosomiasis was carried out in the localities of Aliança, Alegre and Coroatá (districts of Cururupu, São Bento and São João Batista, respectively) in the lowland of the state of Maranhão, after respectively 13, 11 and 4 mass treatments with oxamniquine in the period of ten years (1977-1987). The study included clinical and quantitative fecal examination, skin test for Shistosoma mansoni infection, evaluation of man-water contact of the total population (829 persons) in the three localities and other epidemiological investigations such as infection rate and dynamics of the snail population. After 13 mass treatments in Aliança, the prevalence of S. mansoni infection was reduced from 57.9% to 7.4%. In Coroatá with 11 mass treatments the prevalence fell from 69.2% to 12.8% and in Alegre, with only 4 mass treatments there was pratically no reduction in prevalence: 22.9% to 21%. After mass treatments the type II hepatointestinal clinical form was 10.8% in Aliança, 17.9% in Alegre and 18% in Coroatá. The hepatosplenic (type III) form was not seen in Aliança and Coroatá but unexplanably it was 7.6% in Alegre. There was no correlation between the egg load elimination and the clinical forms.

Epidemiological aspects of American Cutaneous Leishmaniasis in a periurban area of the metropolitan region of Belo Horizonte, Minas Gerais, Brazil

In order to characterize the epidemiology of American Cutaneous Leishmaniasis (ACL) in a periurban area of the municipality of Sabará in the metropolitan region of Belo Horizonte (MRBH), an area until then considered free of the disease, a cross sectional survey was undertaken in 1990. The survey of the population consisted of 1119 interviews and 881 clinical examinations using Montenegro's skin test (MST). A low prevalence (3.7%) of positive MST was encountered. The disease had been occuring in the area for about 20 years in the form of sporadic cases. The predominant species of sandfly both in domestic areas and nearby areas of secondary vegetation was Lutzomyia whitmani. A canine survey of delayed hypersensitivity to the antigen P10,000 identified only one dog with a positive reaction out of 113 examined. The transmission of ACL in MRBH was confirmed. The occurrence of the disease in women, children and individuals with no contact with forest areas as well as the presence of potential vector species in the domiciliar environment, suggests the transmission of the disease in this environment.

Seroepidemiological Studies of Cutaneous Leishmaniasis in the Campeche State of México

Seroepidemiological studies of cutaneous leishmaniasis were carried out on 169 individuals in a rural area of the Campeche state of México. Fifty showed cutaneous lesions suggestive of leishmaniasis, 70% were parasite positive and 96% skin test positive. An overall 40% positivity to skin test with Montenegro's antigen was found. Most of the affected individuals were males from 11 to 30 years-old. Antibodies were determined by immunofluorescent antibody test (IFA) and by Western blot. Two antigen preparations were used, one from a Leishmania mexicana strain which produced localized cutaneous leishmaniasis (LCL) and the other from a diffuse cutaneous leishmaniasis (DCL). In the general population from the area of study 19% gave positive IFA tests with DCL antigen and 20% with LCL antigen while for the patients 67% gave positive IFA tests with DCL and 71% with LCL. By Western blot analysis most of the patients recognized more antigens in the DCL than in the LCL strain. In the DCL strain 78% of patients recognized a 105 kDa, 34% a 139 kDa, 28% a 117 kDa and 26% a 205 kDa MW antigen. In the LCL strain 40% of patients recognized a 205 kDa and 22% a 175 kDa antigens

Response to Heterologous Leishmanins in Cutaneous Leishmaniasis in Nigeria: Discovery of a New Focus

A pilot study was undertaken to preliminary illustrate the leishmanin skin test (LST) positivity to distinct antigen preparations (derived from promastigote of either Leishmania major or L. amazonensis, or pooled L. mexicana, L. amazonensis and L. guyanensis) in cutaneous leishmaniasis (CL) patients and healthy subjects living in two endemic foci in Nigeria. The study was designed to provide insights into whether cross-species leishmanin, such as that prepared from New World Leishmania could be useful to detect cases of Old World leishmanial infection and to compare the results with LST using L. major-derived leishmanin. The overall LST positivity in individuals from Keana tested with the cross-species leishmanin was 28.7% (27/94), while the positivity rate in the subjects from Kanana tested with the same leishmanin was 54.5% (6/11). Lower positivity values were obtained when L. major (12.5%; 11/88) or L. amazonensis (15.8%; 9/57) was tested as antigen in grossly comparable populations. Moreover, the pooled leishmanin identified most of the subjects (13/14; 92.9%) with active or healed CL, and the maximum reaction sizes were found among positive subjects in this group. No healthy controls (10 total) showed specific DTH response. The LST was useful for assessing the prevalence of subclinical infection and for measuring CL transmission over time. We report for the first time the occurrence of CL in Kanana village of Langtang South local government area of Plateau State

Phase 1 Study of an Inactivated Vaccine against American Tegumentary Leishmaniasis in Normal Volunteers in Brazil

A Phase 1 double-blind placebo-controlled study was performed to evaluate a vaccine against American tegumentary leishmaniasis in 61 healthy male volunteers. Side effects and the immune response to the vaccine were evaluated, with 1- and 2- dose schemes, with intervals of 7 or 21 days, each dose containing 1440 mg of protein N antigen of a single strain of Leishmania amazonensis (PH 8) diluted in merthiolated saline (1:10,000). Merthiolated saline and an inert substance were used as placebos. No significant clinical alterations were found following the respective injections in the vaccinated individuals as compared to the placebos, except for local pain, which was associated significantly with injection of the vaccine. The laboratory alterations we observed bore no association with the clinical findings and were unimportant. We observed no differences between the groups with regard to seroconversion or the Montenegro skin test. However, the group that received a single dose of the vaccine and the one that received two doses with a 21-day interval displayed cutaneous induration significantly larger than in the control group, with 100%, 100%, and 66% conversion in the skin test, respectively. We concluded that the vaccine does not present any major side effect that would contraindicate its use in healthy individuals.

Atypical Mucocutaneous Leishmaniasis Caused by Leishmania braziliensis in an Acquired Immunodeficiency Syndrome Patient: T-cell Responses and Remission of Lesions Associated with Antigen Immunotherapy

An atypical case of acquired immunodeficiency syndrome-associated mucocutaneous lesions due to Leishmania braziliensis is described. Many vacuolated macrophages laden with amastigote forms of the parasite were found in the lesions. Leishmanin skin test and serology for leishmaniasis were both negative. The patient was resistant to therapy with conventional drugs (antimonial and amphotericin B). Interestingly, remission of lesions was achieved after an alternative combined therapy of antimonial associated with immunotherapy (whole promastigote antigens). Peripheral blood mononuclear cells were separated and stimulated in vitro with Leishmania antigens to test the lymphoproliferative responses (LPR). Before the combined immunochemotherapy, the LPR to leishmanial antigens was negligible (stimulation index - SI=1.4). After the first course of combined therapy it became positive (SI=4.17). The antigen responding cells were predominantly T-cells (47.5%) most of them with CD8+ phenotype (33%). Very low CD4+ cells (2.2%) percentages were detected. The increased T-cell responsiveness to leishmanial antigens after combined therapy was accompanied by interferon-g (IFN-g) production as observed in the cell culture supernatants. In this patient, healing of the leishmaniasis lesions was associated with the induction of a specific T-cell immune response, characterized by the production of IFN-g and the predominance of the CD8+ phenotype among the Leishmania-reactive T-cells.

Risk Factors for tuberculosis among human immunodeficiency virus-infected persons. A case-control study in Belo Horizonte, Minas Gerais, Brazil (1985-1996)

The objective of this study was to identify tuberculosis risk factors and possible surrogate markers among human immunodeficiency virus (HIV)-infected persons. A retrospective case-control study was carried out at the HIV outpatient clinic of the Universidade Federal de Minas Gerais in Belo Horizonte. We reviewed the demographic, social-economical and medical data of 477 HIV-infected individuals evaluated from 1985 to 1996. The variables were submitted to an univariate and stratified analysis. Aids related complex (ARC), past history of pneumonia, past history of hospitalization, CD4 count and no antiretroviral use were identified as possible effect modifiers and confounding variables, and were submitted to logistic regression analysis by the stepwise method. ARC had an odds ratio (OR) of 3.5 (CI 95% - 1.2-10.8) for tuberculosis development. Past history of pneumonia (OR 1.7 - CI 95% 0.6-5.2) and the CD4 count (OR 0.4 - CI 0.2-1.2) had no statistical significance. These results show that ARC is an important clinical surrogate for tuberculosis in HIV-infected patients. Despite the need of confirmation in future studies, these results suggest that the ideal moment for tuberculosis chemoprophylaxis could be previous to the introduction of antiretroviral treatment or even just after the diagnosis of HIV infection.