The results of five serologic tests (ELISA using promastigote antigen [ELISAp] and recombinant K39 [ELISArK39] and K26 [ELISArK26] antigens, indirect immunofluorescence test using promastigote antigen [IIFT], and immunochromatographic tests using the rK39 antigen [TRALd]) and of the Montenegro skin test (MST) were analyzed in 41 individuals treated for kala-azar and living in Porteirinha, Minas Gerais, Brazil. The tests were carried out 1 week to 12 years after specific treatment. All MSTs during the 8 months after treatment were negative, whereas after 1 year, 28 (84.8%) were positive. Negativity in all serologic tests was observed for 11 (26.8%) of the 41 individuals, whereas positivity in at least one test was observed for 70.3% of subjects evaluated > or = 2 years after treatment. With respect to each exam, positivity was 38.0% for TRALd, 61.9% for ELISA rK39, 47.6% for ELISA rK26, 38.0% for ELISAp, and 40.5% for IIFT. None of the individuals presented recurrence of the disease during the 4 years of follow-up. The tests were repeated in 24 of the 41 individuals, after some time, and the results were the same in 33.3% of the cases. We conclude that serological tests for kala-azar might continue to be positive after treatment of the disease, although this does not indicate a poor prognosis or a poor therapeutic response.

This report describes three elderly patients with mucosal form of American tegumentary leishmaniasis associated with chronic cardiopathy. Due to the known toxicity of classical drugs with activity against Leishmania sp., the patients received three oral courses of azithromycin therapy in single 500 mg daily dose during ten days, every other month. All lesions healed after the third series. One of the patients relapsed and a new series of azithromycin was prescribed. Azithromycin may be an alternative drug for the treatment of leishmaniasis in special situations due to its optimal mucosal and intraphagocyte concentration, single daily posology, high tolerance and oral administration. The mechanism of this drug on Leishmania sp. is unknown at present.

Background. During dengue virus (DV) infection, monocytes produce tumor necrosis factor alpha (TNF-α) and nitric oxide (NO) which might be critical to immunopathogenesis. Since intensity of DV replication may determine clinical outcomes, it is important to know the effects of viral nonstructural protein 1 (NS1) on innate immune parameters of infected patients. The present study investigates the relationships between dengue virus nonstructural protein 1 (NS1) serum levels and innate immune response (TLR4 expression and TNF-α/NO production) of DV infected patients presenting different clinical outcomes. Methodology/Principal Findings. We evaluated NO, NS1 serum levels (ELISA), TNF-α production by peripheral blood mononuclear cells (PBMCs), and TLR4 expression on CD14+ cells from 37 dengue patients and 20 healthy controls. Early in infection, increased expression of TLR4 in monocytes of patients with dengue fever (DF) was detected compared to patients with dengue hemorrhagic fever (DHF). Moreover, PBMCs of DHF patients showed higher NS1 and lower NO serum levels during the acute febrile phase and a reduced response to TLR4 stimulation by LPS (with a reduced TNF-α production) when compared to DF patients. Conclusions/Significance. During DV infection in humans, some innate immune parameters change, depending on the NS1 serum levels, and phase and severity of the disease which may contribute to development of different clinical outcomes.

bIgG avidity tests are used to discriminate acute from chronic infections. There are few reports on the IgG avidity profile of patients with visceral leishmaniasis (VL). This study investigated the anti-Leishmania IgG avidity in patients with classic VL (n ‫؍‬ 10), patients showing clinical cure after treatment (n ‫؍‬ 18), and asymptomatic subjects with at least one positive Leishmania test (n ‫؍‬ 20). All subjects were from areas in Brazil where VL is endemic. Serum samples were collected from each subject on two different occasions. IgG avidity was evaluated by Western blotting. The proportion of high-avidity antibodies was higher in all samples from patients with classic VL. In contrast, low-avidity antibodies predominated in subjects with a history of VL, including 13 cases (72.2%) in the first assessment and 14 (77.8%) in the second. Fifteen (75%) of the asymptomatic subjects presented a predominance of low-avidity antibodies in the first assessment, and the frequency of high-avidity antibodies increased over time in seven subjects (35%) of this group. Antibodies against the 14-and/or 16-kDa antigen fraction were detected in the first assessment in all patients with classic VL, in 10 (55.5%) treated patients, and in 10 (50%) asymptomatic subjects. These were highavidity antibodies in most cases. In the asymptomatic group, an increase in IgG avidity against the 14-and/or 16-kDa antigen fraction was observed in three cases (15%). The results indicate distinct responses in infected and asymptomatic subjects, probably associated with the length of time after infection. In this respect, IgG avidity tests represent a new approach to better characterize asymptomatic VL.

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Abstract. The diagnosis of Leishmania (Leishmania) infantum infection in children from birth may serve as a reference for the early identification of cases that would progress to classical visceral leishmaniasis (VL) in endemic areas. This study prospectively evaluated newborns of mothers living in the municipality of Paracatu, Minas Gerais, Brazil. The infants were followed up at 6-month intervals by clinical examination, serological tests (immunofluorescence [IIF] and enzyme-linked immunosorbent assay with rK39 [ELISA-rK39]) and polymerase chain reaction (PCR) until they had completed 18 months of age. A total of 166 pregnant women were included to evaluate the possible transfer of antibodies or even congenital transmission. Twenty-two of the women tested positive by IIF, four by ELISA-rK39, and one by PCR. Three infants of the 25 women with some positive test results were also positive in the first test (one by IIF, one by ELISA-rK39, and the third by ELISA-rK39 and PCR). One hundred and sixty infants were included in the study; of these, 43 had at least one positive sample over time. However, agreement between tests was low. Follow-up of children with a positive result in the tests studied revealed no progression to classical disease within a period of 18 months. In contrast, two children with negative IIF, PCR, and ELISA-rK39 results developed classical VL at 9 and 12 months of age. In conclusion, a positive test result was variable and sometimes temporary and agreement between tests was low. Therefore, the early diagnosis of Leishmania infection was not associated with the early identification of cases that would progress to classical VL in the endemic area studied.

With the purpose of evaluating the response of sequential applications of Montenegro intradermoreaction (IDRM), we have repeated four times the test in the inhabitants of an endemic area for kala-azar, that resulted negative 3-4 years ago. Firstly, we have repeated three IDRM in those who remained negative, with a 60-day interval among them. In the second stage, we have performed a last reaction in all participants of the study. From the total of 49 individuals with prior negative IDRM, 19 (38.8%) have positivated the test in some of the times, 17 (34.7%) have given up the study and 13 (26.5%) remained with a negative result in all the applications. In the second stage, the repetition of IDRM has shown that from the 14 positive in some of the tests, 8 remained like this and 6 have become negative. Our results confirm the possibility of late hypersensitivity induction in some individuals as a consequence of IDRM application.

RESUMO ABSTRACT Intradermal reactions were performed in 399 individuals by using, simultaneously, the antigen produced by both the Universidade Federal de Minas Gerais and Fundação Instituto Oswaldo Cruz. Each of these antigens was manufactured with promastigotes of Leishmania (L) amazonensis (IFLA/BR/67/PH8). The Fundação Oswaldo Cruz antigen caused a larger number of positive reactions. Discordant reactions occurred in 22% of the individuals.