Cintia Mara Costa de Oliveira

Mayaro Fever in the City of Manaus, Brazil, 2007–2008

Mayaro Alphavirus is an arbovirus that causes outbreaks of acute febrile illness in the Amazon region of South America. We show here the cases of Mayaro fever that occurred in 2007-2008, in Manaus, a large city and capital of the Amazonas State, in Western Brazilian Amazon. IgM antibodies to Mayaro virus (MAYV) were detected by an enzyme immunoassay using infected cell cultures as antigen in the sera of 33 patients from both genera and 6-65 years old. MAYV genome was also detected by RT-PCR in the blood of 1/33 of these patients. The patients presented mainly with headache, arthralgia, myalgia, ocular pain, and rash. These cases of Mayaro fever are likely to represent the tip of an iceberg, and probably a much greater number of cases occurred in Manaus in the study period.

Co-infection of Dengue virus by serotypes 3 and 4 in patients from Amazonas, Brazil

The natural co-infection with dengue virus can occur in highly endemic areas where different serotypes have been observed for many years. We report here four cases of DENV-3/DENV-4 co-infection detected by serological and molecular tests among 674 patients with acute undifferentiated fever from the tropical medicine reference center of Manaus City, Brazil, between 2005 and 2010. Analysis of the sequences obtained indicated the presence of genotype 3 and 1 for DENV-3 and DENV-4 respectively.

Chronic HDV/HBV co-infection: Predictors of disease stage – a case series of HDV-3 patients

BACKGROUND & AIMS Chronic HDV/HBV co-infection is perhaps the most intriguing amongst all viral hepatitis. Only few studies focus deeply on this topic, particularly with patients infected with HDV-3. This study aimed to identify predictors of advanced disease, examining a cross-sectional data of 64 patients. METHODS Histological grading was used to characterize the disease stages and viral loads were tested as predictors of necroinflammatory activity and fibrosis. RESULTS We identified three HDV/HBV co-infection patterns: patients with predominant HDV replication (56.3%), patients with similar viral loads of both viruses (40.6%), and patients with predominant HBV replication (3.1%). Mean HDV-RNA showed a positive trend regarding inflammatory activity and grade of fibrosis. HDV viral load correlated positively with serum levels of liver enzymes and inversely with platelets count. HBV viral load showed no correlation with any of the above parameters. Advanced fibrosis was associated with age, splenomegaly, and HDV viral load of more than 2 log10. Multiple logistic regression confirmed the independent effect of HDV viral predominance. Advanced necroinflammatory activity was independently associated with HDV viral load and splenomegaly. CONCLUSIONS HDV may possibly play an important and direct role in the establishment of necroinflammatory activity and fibrosis. Data show an indigenous HDV genotype, HDV-3, similar to those described in the Amazon region.

High Prevalence Detection of Chlamydia trachomatis by Polymerase Chain Reaction in Endocervical Samples of Infertile Women Attending University Hospital in Manaus-Amazonas, Brazil

Background: We established for the first time the prevalence of Chlamydia trachomatis infection among infertile women in Manaus Amazonas Brazil using the polymerase chain reaction (PCR) technique. Methods: 106 women were studied at a public university hospital fertility clinic for infertility problems correlated with chlamydia infection. Social-economic and clinical information was obtained before medical examination to obtain samples for the amplification of C. trachomatis DNA plasmid. Results: The prevalence of chlamydial infection among infertile women was 52.8, and 51.8% of the positive participants were older than 30 years of age (p = 0.8697). Of the 56 women positive for C. trachomatis, 31 (55.4%) had never given birth, while 9 (16%) had a pregnancy resulting in fetal death. Our findings also revealed that these patients had a low socio-economic status and high unemployment (p = 0.0274), and a significant association of 5% (p < 0.05) of chlamydial infection with family income. Conclusions: Due to the high prevalence of C. trachomatis, concerns about effects on reproductive health and fertility are undertaken. Therefore, we believe it is extremely necessary to implement large-scale PCR-based screening as part of routine clinical detection programs concerning preventive effects of chlamydial infection among this population.

Characterization of HBeAg-negative chronic hepatitis B in western Brazilian Amazonia

The present study was conducted with 55 patients native from western Brazilian Amazonia, who were HBV-DNA positive after seroconversion of HBeAg. It is a descriptive case study, with the patients separated into two groups: with hepatitis and without hepatitis on histological examination. The aim of the present study was to describe the clinical and molecular characteristics of patients who are chronic carriers of HBsAg. The prevalence of hepatitis was 63.64%, with a predominance of males (41.82%) and a mean age of 42.5 years, occurring mostly in natives of the southeast sub-region (32.73%). Time was a variable proportional to the course of the disease and the most frequent symptoms were: dyspepsia, asthenia and loss of libido with the majority of the patients having history of prior contact with HBV or positive family history. Splenomegalia was the most frequent sign (40%). Among the tests, platelet count, serum albumin and prothrombin activity were significant in the diagnosis of hepatitis. Alpha-fetoprotein was greater in patients with hepatitis, and hepatocellular carcinoma was detected in 3.63% of the patients with hepatic cirrhosis. Three types of HBV genotypes were diagnosed: A, D and F in the samples amplified for gene S. Genotype A (AA) was observed in 54.54% of the cases with hepatitis, in contrast to other studies showing the predominance of genotype F in this region. We observed mutations in 36.36%, with a predominance of the mutations in the core promoter region (31.81%), due to the greater prevalence of genotype A in this study.

Serological evidence of hantavirus infection in rural and urban regions in the state of Amazonas, Brazil

Hantavirus disease is caused by the hantavirus, which is an RNA virus belonging to the family Bunyaviridae. Hantavirus disease is an anthropozoonotic infection transmitted through the inhalation of aerosols from the excreta of hantavirus-infected rodents. In the county of Itacoatiara in the state of Amazonas (AM), Brazil, the first human cases of hantavirus pulmonary and cardiovascular syndrome were described in July 2004. These first cases were followed by two fatal cases, one in the municipality of Maués in 2005 and another in Itacoatiara in 2007. In this study, we investigated the antibody levels to hantavirus in a population of 1,731 individuals from four different counties of AM. Sera were tested by IgG/IgM- enzyme-linked immune-sorbent assay using a recombinant nucleocapsid protein of the Araraquara hantavirus as an antigen. Ten sera were IgG positive to hantavirus (0.6%). Among the positive sera, 0.8% (1/122), 0.4% (1/256), 0.2% (1/556) and 0.9% (7/797) were from Atalaia do Norte, Careiro Castanho, Itacoatiara and Lábrea, respectively. None of the sera in this survey were IgM-positive. Because these counties are distributed in different areas of AM, we can assume that infected individuals are found throughout the entire state, which suggests that hantavirus disease could be a local emerging health problem.

Hepatite crônica B oculta: prevalência e aspectos clínicos em população de elevada endemicidade de infecção pelo vírus da hepatite B na Amazônia Ocidental Brasileira

A persistent form of the hepatitis B virus called occult chronic hepatitis B has recently been described. Its prevalence and physiopathology are unknown. The aim of this study was to evaluate the occurrence of this clinical entity among patients in the Brazilian Amazon region. Out of 51 anti-HBc total-positive patients who were tested using the polymerase chain reaction, 17% were positive. We did not find any associations with classical risk factors for hepatitis B virus infection or with biochemical tests, hematological tests or histological patterns. However, the jaundiced and HIV-positive patients showed a statistical association with the presence of hepatitis B virus-DNA. The results demonstrated that occult hepatitis B occurred among our patients, but at prevalence rates lower than expected for this region. We believe that despite the small sample size, the occurrence might have been found to be greater if we had used primers for the S, C and X regions of the hepatitis B virus genome, thereby increasing the sensitivity of the test.

Combining diagnostic procedures for the management of leishmaniasis in areas with high prevalence of Leishmania guyanensis

BACKGROUND The Amazon region corresponds to approximately 40% of the cases of leishmaniasis in Brazil. We report a prospective study with 180 patients conducted in a health care unit that diagnoses 10% of the cases of leishmaniasis in the Brazilian Amazon. The study addresses how a combination of procedures improves diagnosis in areas with high prevalence of Leishmania guyanensis. OBJECTIVES to evaluate diagnostic methods in areas with high prevalence of Leishmania guyanensis. METHODS All subjects were amastigote-positive by direct microscopic examination of lesion scarifications. We conducted skin biopsy and histopathology, polymerase chain reaction and parasite cultivation. RESULTS Polymerase chain reaction detected almost ninety percent of infections when two amplification protocols were used (mini-exon and HSP-70). HSP-70 specific polymerase chain reaction matched the sensitivity of parasite cultivation plus histopathology. CONCLUSION The best combination was polymerase chain reaction plus histopathology, which increased diagnostic sensitivity to 94%. Species discrimination by polymerase chain reaction disclosed prevalence of human infections with Leishmania guyanensis of 94% and with Leishmania braziliensis of 6% for this region.

HIV-associated tuberculous lymphadenitis: the importance of polymerase chain reaction (PCR) as a complementary tool for the diagnosis of tuberculosis - a study of 104 patients

FUNDAMENTOS: A linfadenite e comum em pacientes HIV-positivos. O diagnostico das infeccoes associadas a essa condicao e complexo, especialmente em relacao a tuberculose. A deteccao rapida e especifica do Mycobacterium tuberculosis (M. tuberculosis) e essencial para o tratamento adequado. Alem disso, frequentes causas de linfadenites tais como as relacionadas a linfoma, histoplasmose, e outras, devem ser afastadas. OBJETIVOS: Avaliar a importância da biopsia cirurgica excisional das linfadenites e realizacao dos exames histopatologicos, exames baciloscopicos (Ziehl-Neelsen), cultura (Lowenstein-Jensen) e reacao em cadeia da polimerase (PCR) com finalidade diagnostica METODOS: Desenvolveu-se um protocolo para biopsias excisionais de linfonodos, adotando-se os seguintes procedimentos: exame direto de esfregacos corados pelo metodo de Ziehl-Neelsen, cultura em meio de Lowenstein-Jensen, exame anatomo-patologico e PCR. RESULTADOS: Ao todo foram incluidos 104 pacientes, e o exame histopatologico evidenciou 36% (n = 38 pacientes) de casos de linfadenite cronica inespecifica, 26% (n = 27) de linfadenite tuberculosa, 10,5% (n =11) de linfoma e 8,7% (n = 9) de histoplasmose. Atraves da cultura no meio de Lowenstein-Jensen, os casos positivos para linfadenite tuberculosa aumentaram para 30%. A PCR detectou M. tuberculosis em 6 das 38 amostras de linfadenite cronica inespecifica. Tres desses pacientes foram acompanhados, exibiram sintomas de tuberculose e foram curados apos tratamento especifico. CONCLUSAO: Os dados obtidos neste trabalho sugerem que em todos os casos de linfadenopatia deve-se realizar exame histopatologico, cultura em Lowenstein-Jensen ou Ogawa e reacao em cadeia da polimerase. A reacao em cadeia da polimerase pode ser util na deteccao precoce e acurada de casos de TB extrapulmonar nos pacientes HIV-positivos com linfadenopatias, evitando-se o uso de tratamentos empiricos e o eventual desenvolvimento de cepas resistentes.BACKGROUND Lymphadenitis is common in HIV-positive patients. Diagnosis of the infections associated with this condition is complex, particularly in the case of tuberculosis. Rapid and specific detection of Mycobacterium tuberculosis (M. tuberculosis) is fundamental in ensuring adequate treatment. In addition, frequent causes of lymphadenitis such as those associated with lymphoma and histoplasmosis, among others, must be eliminated as possible causes. OBJECTIVES To evaluate the accuracy of polymerase chain reaction as a tool for the diagnosis of lymphadenitis resulting from M. tuberculosis. METHODS In this study, a protocol was developed using the following procedures: direct microscopy using Ziehl-Neelsen staining, culture in Lowenstein-Jensen medium, histology and polymerase chain reaction. RESULTS A total of 104 patients were included in the study. According to histopathology, 38 patients (36%) were found to have nonspecific chronic lymphadenitis, 27 (26%) had tuberculous lymphadenitis, 11 patients (10.5%) had lymphoma and 9 (8.7%) had histoplasmosis. When Lowenstein-Jensen culture was performed, positive tests for tuberculous lymphadenitis increased by 30%. With polymerase chain reaction, M. tuberculosis DNA was detected in 6 out of 38 samples of non-specific chronic lymphadenitis. Three of these patients were followed up, developed symptoms of tuberculosis and were cured following specific treatment. CONCLUSION The data obtained in this study suggest that all cases of lymphadenopathies should be submitted to histopathology, Lowenstein-Jensen or Ogawa culture and polymerase chain reaction. Polymerase chain reaction may prove to be useful in providing an early and accurate detection of cases of extrapulmonary tuberculosis in HIV-positive patients with lymphadenopathies, avoiding empirical treatment and the possible development of resistant strains.

Identification of dengue viruses in naturally infected Aedes aegypti females captured with BioGents (BG)-Sentinel traps in Manaus, Amazonas, Brazil

INTRODUCTION In Manaus, the first autochthonous cases of dengue fever were registered in 1998. Since then, dengue cases were diagnosed by the isolation of viruses 1, 2, 3, and 4. METHODS One hundred eighty-seven mosquitoes were collected with BioGents (BG)-Sentinel traps in 15 urban residential areas in the Northern Zone of Manaus and processed by molecular tests. RESULTS Infections with dengue viruses 1, 2, 3, and 4 and a case of co-infection with dengue viruses 2 and 3 were identified. CONCLUSIONS These findings corroborate the detection of dengue in clinical samples and reinforce the need for epidemiological surveillance by the Health authorities.