RESUMO Objetivo: Determinar a prevalência de alterações oculares em pacientes com diagnóstico de dengue, internados em um centro de referência para doenças infecciosas e parasitárias em Manaus (AM), Brasil. Métodos: Estudo observacional, analítico e prospectivo de série de casos de 33 pacientes admitidos no hospital com exames de patologia clínica positivos durante um período de 90 dias de uma epidemia de dengue em 2011. As investigações incluíram medida da acuidade visual, avaliação macular com tela de Amsler, biomicroscopia de fundo de olho, retinografia e tomografia de coerência ótica. Resultados: A idade média dos pacientes foi de 35,48 anos (idade mínima de 17 anos e máxima de 69 anos). Os principais sintomas relatados foram visão turva, seguida de dor retro-ocular, fotopsia, halos, corpos estranhos, escotoma, visão dupla e moscas volantes. A acuidade visual variou entre 20/20 e 20/40 (mediana 20/30). A avaliação macular com a tela de Amsler foi insatisfatória em três doentes. Os achados retinianos mais comuns foram edema perimacular, edema macular, hemorragia retiniana, vasculite e alterações no epitélio pigmentar da retina. A tomografia de coerência óptica mostrou edema da retina em 16 doentes (51,51%). Conclusões: Em todos os casos, a doença foi autolimitada e resolveu-se espontaneamente sem tratamento. Este estudo confirma, portanto, que as manifestações oculares da dengue são variadas e frequentes. Objetivo AM, AM , (AM) Brasil Métodos observacional 3 9 2011 olho ótica Resultados 3548 35 48 35,4 1 6 anos. . anos) turva retroocular, retroocular retro ocular, ocular retro-ocular fotopsia halos estranhos escotoma volantes 2020 20 20/2 2040 40 20/4 mediana 20/30. 2030 20/30 30 20/30) perimacular retiniana 51,51%. 5151 51,51% 51 (51,51%) Conclusões resolveuse resolveu se tratamento confirma portanto frequentes (AM 201 354 4 35, 202 2 20/ 204 203 20/3 515 51,51 5 (51,51% 51,5 (51,51 51, (51,5 (51, (51 (5 (

ABSTRACT Objective: To determine the prevalence of ocular alterations in patients diagnosed with dengue, admitted to a reference center for infectious and parasitic diseases in Manaus (AM), Brazil. Methods: This was an observational, analytical, and prospective case series study with 33 patients admitted to the hospital with positive clinical pathology tests during a 90-day period of a dengue epidemic in 2011. The investigations included measurement of visual acuity, macular assessment with Amsler grid test, fundus biomicroscopy, retinography and optical coherence tomography. Results: The average age of the patients was 35.48 years (minimum age 17 years and maximum 69 years). The main symptoms reported were blurred vision, followed by retro-ocular pain, photopsia, halos, foreign bodies, scotoma, double vision, and floaters. Visual acuity ranged from 20/20 to 20/40 (median 20/30). Macular assessment with Amsler Grid Test was unsatisfactory in three patients. The most common retinal findings were perimacular edema, macular edema, retinal hemorrhage, vasculitis, and changes in the retinal pigment epithelium. Optical coherence tomography showed retinal edema in 16 patients (51.51%). Conclusions: In all cases, the disease was self-limiting and resolved spontaneously without treatment. Therefore, this study confirms that ocular manifestations in dengue fever are varied and frequent. Objective AM, AM , (AM) Brazil Methods observational analytical 3 90day day 90 2011 test biomicroscopy Results 3548 35 48 35.4 minimum 1 6 years. . years) vision retroocular retro pain photopsia halos bodies scotoma floaters 2020 20 20/2 2040 40 20/4 median 20/30. 2030 20/30 30 20/30) hemorrhage vasculitis epithelium 51.51%. 5151 51.51% 51 (51.51%) Conclusions cases selflimiting self limiting treatment Therefore frequent (AM 9 201 354 4 35. 202 2 20/ 204 203 20/3 515 51.51 5 (51.51% 51.5 (51.51 51. (51.5 (51. (51 (5 (

Resumo: Introdução: Além de demorada, a mentoria em Medicina ocorre em vários níveis e é complexa, pois pode incluir várias combinações de ensino, prática clínica, atendimento ao paciente e pesquisa. Relato de experiência: Trata-se de um relato de experiência individual de uma mentorada em um programa de residência médica em patologia do Hospital Universitário Getúlio Vargas, de Manaus, no Amazonas. Descrevem-se os benefícios individuais e coletivos de uma mentoria fora de um programa formal, orientada pelo discernimento e pela maturidade de relacionamento entre mentor e mentorada. Discussão: Discentes de programa de residência médica podem se beneficiar sobremaneira, pessoal e profissionalmente, de mentorias bem conduzidas. Conclusão: No relacionamento de mentoria, são imprescindíveis qualidades como respeito mútuo, discernimento e abnegação, para que o mentorado cresça e desenvolva uma identidade profissional independente, ainda que atrelada à relação de mentoria, e amadurecida, em seu pleno desenvolvimento, a fim de que ele seja um novo mentor e novos alunos sejam beneficiados.

Abstract: Introduction: Mentoring in medicine is time-consuming on several levels and complex, as it can include various combinations of teaching, clinical practice, patient care, and research. Experience report: This report is on the individual experience of a mentee in a medical residency program in Pathology at the Getúlio Vargas University Hospital (Manaus-AM). The individual and collective benefits of mentoring outside a formal program are described, guided by the discernment and maturity of the relationship between mentor and mentee. Discussion: Medical residency program students can benefit greatly, both personally and professionally, from well-conducted mentoring. Conclusion: In the mentoring relationship, qualities such as mutual respect, discernment, and selflessness are essential so that the mentee grows and develops a fully developed and independent professional identity, albeit bound to the mentoring relationship, in order for him become a new mentor and to benefit new students.

Abstract INTRODUCTION: Electron microscopy (EM) is a rapid and effective tool that can be used to create images of a whole spectrum of virus-host interactions and, as such, has long been used in the discovery and description of viral mechanisms. METHODS: Electron microscopy was used to evaluate the pulmonary pathologies of postmortem lung sections from three patients who died from infection with SARS-associated coronavirus 2 (SARS-CoV-2), a new member of the Coronaviridae family. RESULTS: Diffuse alveolar damage (DAD) was predominant in all three patients. The early exudative stage was characterized principally by edema and extravasation of red blood cells into the alveolar space with injury to the alveolar epithelial cells; this was followed by detachment, apoptosis, and necrosis of type I and II pneumocytes. The capillaries exhibited congestion, exposure of the basement membrane from denuded endothelial cells, platelet adhesion, fibrin thrombi, and rupture of the capillary walls. The proliferative stage was characterized by pronounced proliferation of type II alveolar pneumocytes and multinucleated giant cells. The cytopathic effect of SARS-CoV-2 was observed both in degenerated type II pneumocytes and freely circulating in the alveoli, with components from virions, macrophages, lymphocytes, and cellular debris. CONCLUSIONS: Viral particles consistent with the characteristics of SARS-CoV-2 were observed mainly in degenerated pneumocytes, in the endothelium, or freely circulating in the alveoli. In the final stage of illness, the alveolar spaces were replaced by fibrosis.

Abstract Some epidermal alterations in measles has been described, such as keratinocytes apoptotic, parakeratosis, giant-cell formation, intranuclear and cytoplasmic inclusions, dyskeratosis, spongiosis, and intracellular edema. The authors report for the first time in human a case of measles with the presence of multinucleated giant cells in the hair follicle and dyskeratosis in acrosyringium.

Abstract We present postmortem evidence of invasive pulmonary aspergillosis (IPA) in a patient with severe COVID-19. Autopsies of COVID-19 confirmed cases were performed. The patient died despite antimicrobials, mechanical ventilation, and vasopressor support. Histopathology and peripheral blood galactomannan antigen testing confirmed IPA. Aspergillus penicillioides infection was confirmed by nucleotide sequencing and BLAST analysis. Further reports are needed to assess the occurrence and frequency of IPA in SARS-CoV-2 infections, and how they interact clinically.

Abstract The involvement of Mycobacterium tuberculosis in the central nervous system (CNS) is an uncommon and devastating manifestation of tuberculosis. We report a case of disseminated tuberculosis presenting as meningoencephalitis, hypothalamic involvement with extension to the hypophysis, and secondary insipidus diabetes diagnosed at autopsy.

RESUMO A patologia deve ter como meta um diagnóstico correto e completo para o paciente, em tempo hábil, de maneira útil e compreensível para o médico assistente. No entanto, na prática diária, são múltiplas as possibilidades de erros no laboratório de patologia, com diversos impactos na assistência e no prognóstico do paciente. Nesta revisão, serão abordados os diferentes conceitos de erros e concordância diagnóstica em patologia, em que momento do processo diagnóstico os erros são mais frequentes, bem como a proposta de soluções para minimizar a chance de sua ocorrência.

ABSTRACT Pathology must aim at a correct and complete diagnosis for the patient, timely, useful and understandable to the physician assistant. However, in daily practice, there are multiple possibilities of errors in the pathology laboratory, with several impacts on patient care and prognosis. In this review, we discuss the different concepts of error and diagnostic concordances in pathology, at which point in the diagnostic process the errors are more frequent, and propose solutions to minimize the chance of their occurrence.

Abstract: Freshwater stingray injuries are a common problem in the Brazilian Amazon, affecting mostly riverine and indigenous populations. These injuries cause severe local and regional pain, swelling and erythema, as well as complications, such as local necrosis and bacterial infection. Herein, we report a case of bacterial infection and hallux necrosis, after a freshwater stingray injury in the Brazilian Amazon, which eventually required amputation. Different antimicrobial regimens were administered at different stages of the disease; however, avoiding amputation through effective treatment was not achieved.

Synovial sarcomas are rare malignant tumors affecting mainly young adults, presenting as a slow growth mass located in deep soft tissues of extremities, near the joints. In this report a 34-year-old male patient, presented an ulcerovegetative lesion on the right wrist which was completely excised. Histopathology and immunohistochemistry confirmed synovial sarcomas with poorly differentiated cells. This patient presented 11 months later with ipsilateral axillary lymph node metastasis, which emphasizes the unfavorable prognosis of this synovial sarcoma variant. The indolent growth pattern of this sarcoma justifies the well circumscribed initial stages, which progressively infiltrate adjacent structures with lung metastasis (80%) and lymph node involvement (20%) and thus corroborates the importance of early diagnosis and proper treatment.

OBJETIVO: Avaliar a acurácia da citologia cervicovaginal realizada no principal laboratório do Estado de Roraima, por concordância entre avaliadores (monitoramento externo) e com resultados histopatológicos.MÉTODOS: Lâminas de 100 mulheres, de uma amostra de conveniência de base populacional, foram avaliadas pelo LAPER, principal laboratório de referência do Sistema Único de Saúde do Estado de Roraima e reavaliadas por médicos patologistas experts externos ao laboratório. Foram avaliados índice Kappa, sensibilidade e especificidade. O estudo foi aprovado pela Coordenação do Laboratório Estadual e pelo Comitê de Ética em Pesquisa da Universidade Federal de Roraima.RESULTADOS: Quanto à prevalência de atipias celulares (relacionadas ao papilomavírus humano), não houve concordância entre resultados emitidos pelo LAPER e pelos patologistas externos (k=0,21). Constatou-se baixa sensibilidade (28,5%) e especificidade de 89,2% para o desempenho do LAPER, com elevada proporção de resultados falsos positivos e falsos negativos. Os laudos citológicos de patologistas externos apresentaram sensibilidade e especificidade maiores (71,4 e 98,9%, respectivamente), descartando que erros de coleta e coloração possam explicar o baixo desempenho do LAPER.CONCLUSÃO: O baixo desempenho diagnóstico da citologia cervicovaginal pode ser uma barreira para o controle do câncer de colo de útero em Roraima. Ressalta-se a necessidade de capacitação profissional e monitoramento interno e externo em Estados brasileiros com alta incidência de câncer de colo de útero.

PURPOSE: To evaluate the validity of cervicovaginal cytology performed at LAPER, the main Laboratory of Pathology of the State of Roraima, Brazil, by interrater agreement (external monitoring) and agreement with histopathologic results.METHODS: One hundred women were included, a population-based convenience sample. Their cervical cytological exams were evaluated by the laboratory staff and reviewed by expert medical pathologists, external to the laboratory. Cohen's Kappa index, sensitivity and specificity were evaluated. The study was approved by LAPER coordination and Federal University of Roraima Research Ethics Commitee.RESULTS: Regarding the prevalence of human papillomavirus-related atypical, there was no concordance between the results issued by LAPER and by the external pathologists (k=0.21). A low sensitivity (28.5%) and specificity (89,2%) was detected for the diagnostic performance of LAPER, with a high proportion of false positive and false negative results. The cytological reports of the external pathologists showed higher sensitivity and specificity (71.4 and 98.9%, respectively), ruling out the possibility that errors related to collection methods and staining would explain the low performance of the laboratory.CONCLUSION: A low diagnostic accuracy of cervicovaginal cytology can be a barrier against the control of cervical cancer in Roraima. We emphasize the need for professional training and internal and external monitoring in Brazilian states with a high incidence of cervical cancer.

O estudo descreve o perfil das notificações de sífilis em gestantes e sífilis congênita no Estado do Amazonas, Brasil, entre 2007 e 2009, e verifica a subnotificação em bases de dados do Sistema Nacional de Agravos de Notificação (SINAN) e a ocorrência de óbitos perinatais associados à sífilis congênita não notificados no Sistema de Informação de Mortalidade (SIM). Estudo seccional com relacionamento entre SINAN e SIM. Ocorreram 666 notificações de sífilis em gestantes, sendo 224 em 2007 (taxa detecção de 3,8/1.000 nascidos vivos); 244 (4,5/1.000) em 2008 e 198 (4,0/1.000) em 2009. Encontraram-se 486 casos de sífilis congênita, sendo 153 (incidência: 2,1/1.000) em 2007, 193 (2,6/1.000) em 2008 e 140 (2,0/1.000) em 2009. Após o relacionamento das bases-SINAN, 237 (35,6%) gestantes tinham casos de sífilis congênita notificados. No SIM, constavam 4.905 óbitos perinatais, sendo 57,8% fetais. No relacionamento do SIM/SINAN-sífilis congênita foram encontrados 13 registros pareados. A utilização do SINAN e SIM podem não refletir a total magnitude da sífilis, mas formam base para o monitoramento e análise da situação de saúde, tendo em vista o planejamento e a gestão.

This study analyzes notification of syphilis in pregnancy and congenital syphilis in Amazo- nas State, Brazil, from 2007 to 2009 and verifies underreporting in databases in the National Information System on Diseases of Notification (SINAN) and the occurrence of perinatal deaths associated with congenital syphilis and not reported in the Mortality Information System (SIM). This was a cross-sectional study with probabilistic record linkage between the SINAN and SIM. There were 666 reports of syphilis in pregnant women, including 224 in 2007 (3.8/1,000), 244(4.5/1,000) in 2008, and 198(4.0/1,000) in 2009. The study found 486 cases of congenital syphilis, of which 153 in 2007 (2.1/1,000), 193 in 2008 (2.6/1,000), and 140 in 2009 (2.0/1,000). After linkage of the SINAN databases, 237 pregnant women (35.6%) had cases of congenital syphilis reported. The SIM recorded 4,905 perinatal deaths, of which 57.8% were stillbirths. Probabilistic record linkage between SIM and SINAN-Congenital Syphilis yielded 13 matched records. The use of SINAN and SIM may not reflect the total magnitude of syphilis, but provide the basis for monitoring and analyzing this health problem, with a view towards planning and management.

El estudio describe el perfil de las notificaciones de sífilis en mujeres embarazadas y sífilis congénita en la Amazonía entre 2007 y 2009, analizando el sub-registro en las bases de datos del Sistema Nacional de Enfermedades de Declaración Obligatoria (SINAN) y la ocurrencia de muertes perinatales, asociadas con sífilis congénita no declarada el Sistema de Información sobre la Mortalidad (SIM). Se trata de un estudio transversal de relación entre SINAN y SIM. Hubo 666 notificaciones de sífilis en mujeres embarazadas, y 224 en 2007 (tasa de detección de 3,8/1.000 nacidos vivos), 244 (4,5/1.000) en 2008 y 198 (4,0/1.000) en 2009. Así como 486 casos de sífilis congénita, 153 (incidencia: 2,1/1.000) en 2007, 193 (2,6/1.000) en 2008 y 140 (2,0/1.000) en 2009. Después de registrar la vinculación –SINAN, 237 (35,6%) mujeres habían reportado casos de sífilis congénita. Estaba presente en 4.905 de muertes perinatales, y en un 57,8% del feto. Se determinó la asociación de SIM/SINAN sífilis congénita –en 13 registros coincidentes. El uso de SIM SINAN puede no reflejar toda la magnitud de la sífilis, pero constituye la base para el seguimiento y análisis de la situación de salud, con vistas a la planificación y gestión.

O estudo descreve o perfil das notificações de sífilis em gestantes e sífilis congênita no Estado do Amazonas, Brasil, entre 2007 e 2009, e verifica a subnotificação em bases de dados do Sistema Nacional de Agravos de Notificação (SINAN) e a ocorrência de óbitos perinatais associados à sífilis congênita não notificados no Sistema de Informação de Mortalidade (SIM). Estudo seccional com relacionamento entre SINAN e SIM. Ocorreram 666 notificações de sífilis em gestantes, sendo 224 em 2007 (taxa detecção de 3,8/1.000 nascidos vivos); 244 (4,5/1.000) em 2008 e 198 (4,0/1.000) em 2009. Encontraram-se 486 casos de sífilis congênita, sendo 153 (incidência: 2,1/1.000) em 2007, 193 (2,6/1.000) em 2008 e 140 (2,0/1.000) em 2009. Após o relacionamento das bases-SINAN, 237 (35,6%) gestantes tinham casos de sífilis congênita notificados. No SIM, constavam 4.905 óbitos perinatais, sendo 57,8% fetais. No relacionamento do SIM/SINAN-sífilis congênita foram encontrados 13 registros pareados. A utilização do SINAN e SIM podem não refletir a total magnitude da sífilis, mas formam base para o monitoramento e análise da situação de saúde, tendo em vista o planejamento e a gestão.

This study analyzes notification of syphilis in pregnancy and congenital syphilis in Amazo- nas State, Brazil, from 2007 to 2009 and verifies underreporting in databases in the National Information System on Diseases of Notification (SINAN) and the occurrence of perinatal deaths associated with congenital syphilis and not reported in the Mortality Information System (SIM). This was a cross-sectional study with probabilistic record linkage between the SINAN and SIM. There were 666 reports of syphilis in pregnant women, including 224 in 2007 (3.8/1,000), 244(4.5/1,000) in 2008, and 198(4.0/1,000) in 2009. The study found 486 cases of congenital syphilis, of which 153 in 2007 (2.1/1,000), 193 in 2008 (2.6/1,000), and 140 in 2009 (2.0/1,000). After linkage of the SINAN databases, 237 pregnant women (35.6%) had cases of congenital syphilis reported. The SIM recorded 4,905 perinatal deaths, of which 57.8% were stillbirths. Probabilistic record linkage between SIM and SINAN-Congenital Syphilis yielded 13 matched records. The use of SINAN and SIM may not reflect the total magnitude of syphilis, but provide the basis for monitoring and analyzing this health problem, with a view towards planning and management.

El estudio describe el perfil de las notificaciones de sífilis en mujeres embarazadas y sífilis congénita en la Amazonía entre 2007 y 2009, analizando el sub-registro en las bases de datos del Sistema Nacional de Enfermedades de Declaración Obligatoria (SINAN) y la ocurrencia de muertes perinatales, asociadas con sífilis congénita no declarada el Sistema de Información sobre la Mortalidad (SIM). Se trata de un estudio transversal de relación entre SINAN y SIM. Hubo 666 notificaciones de sífilis en mujeres embarazadas, y 224 en 2007 (tasa de detección de 3,8/1.000 nacidos vivos), 244 (4,5/1.000) en 2008 y 198 (4,0/1.000) en 2009. Así como 486 casos de sífilis congénita, 153 (incidencia: 2,1/1.000) en 2007, 193 (2,6/1.000) en 2008 y 140 (2,0/1.000) en 2009. Después de registrar la vinculación –SINAN, 237 (35,6%) mujeres habían reportado casos de sífilis congénita. Estaba presente en 4.905 de muertes perinatales, y en un 57,8% del feto. Se determinó la asociación de SIM/SINAN sífilis congénita –en 13 registros coincidentes. El uso de SIM SINAN puede no reflejar toda la magnitud de la sífilis, pero constituye la base para el seguimiento y análisis de la situación de salud, con vistas a la planificación y gestión.

OBJECTIVES:The aim of the present study was to determine the Chlamydia trachomatis prevalence and to identify the demographic, behavioural and clinical factors associated with C. trachomatis in human immunodeficiency virus infected men.STUDY:This was a cross-sectional study of C. trachomatis prevalence among human immunodeficiency virus-infected men enrolled at the Outpatient clinic of acquired immunodeficiency syndrome of the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado in Manaus, Amazonas, Brazil. C. trachomatis deoxyribonucleic acid from urethral samples was purified and submitted to real time polymerase chain reaction to identify the presence of C. trachomatis.RESULTS:A total of 276 human immunodeficiency virus-infected men were included in the study. The prevalence of C. trachomatis infection was 12% (95% confidence interval 8.1%-15.7%). The mean age of the participants was 34.63 (standard deviation 10.80) years. Of the 276 human immunodeficiency virus-infected men, 93 (56.2%) had more than one sexual partner in the past year and 105 (38.0%) reported having their first sexual intercourse under the age of 15 years. Men having sex with men and bisexuals amounted to 61.2% of the studied population. A total of 71.7% had received human immunodeficiency virus diagnosis in the last three years and 55.1% were using antiretroviral therapy. Factors associated with C. trachomatis infection in the logistic model were being single (p<0.034), men having sex with men (p<0.021), and having previous sexually transmitted diseases (p<0.001).CONCLUSION:The high prevalence of C. trachomatis infection among human immunodeficiency virus-infected men highlights that screening human immunodeficiency virus-infected men for C. trachomatis, especially among men having sex with men, is paramount to control the spread of C. trachomatis infection.

OBJETIVO: Avaliar a custo-efetividade da vacinação contra o papilomavírus humano (HPV) na prevenção do câncer de colo de útero na região Amazônica brasileira. MÉTODOS: Um modelo de coorte Markov foi desenvolvido para simular a história natural do HPV e seu progresso para câncer de colo de útero, considerando os atuais programas de prevenção e os custos de tratamento. As probabilidades de um ano de transição foram baseadas principalmente em dados empíricos de estudos locais e nacionais. O modelo avaliou a adição da vacina a três cenários de rastreio de câncer de colo de útero (0, 3 ou 10 exames ao longo da vida). RESULTADOS: O cenário de três exames de Papanicolau resultou em calibração satisfatória (caso base). A adição de vacinação contra o HPV reduziria em 35% a incidência de câncer de colo de útero (70% de cobertura de vacinação). A razão incremental de custo-efetividade foi US$ 825 para cada ano de vida ajustado para qualidade ganho. A análise de sensibilidade confirma a robustez deste resultado, e a duração de imunidade foi o parâmetro com maior variação na razão incremental de custo-efetividade. CONCLUSÃO A vacinação tem um perfil favorável em termos de custo-utilidade, e sua inclusão no calendário de imunização resultaria em redução substancial de incidência e de mortalidade relacionadas ao câncer de colo de útero na região Amazônica brasileira.

OBJECTIVE: To assess the cost-utility of the human papillomavirus (HPV) vaccination on the prevention of cervical cancer in the Brazilian Amazon region. METHODS: AMarkov cohort modelwas developed to simulate the natural evolution of HPV and its progress to cervical cancer, considering the current preventive programs and treatment costs. The one-year transition probabilities were mainly based on empirical data of local and national studies. The model evaluated the addition of the vaccine to three cervical cancer-screening scenarios (0, 3 or 10 exams throughout life). RESULTS: The scenario of three Pap tests resulted in satisfactory calibration (base case). The addition of HPV vaccination would reduce by 35% the incidence of cervical cancer (70% vaccination coverage). The incremental cost-effectiveness ratio was US$ 825 for each quality-adjusted life year gained. The sensitivity analysis confirms the robustness of this result, and duration of immunity was the parameter with greater variation in incremental cost-effectiveness ratio. CONCLUSION: Vaccination has a favorable profile in terms of cost-utility, and its inclusion in the immunization schedule would result in a substantial reduction in incidence and mortality of invasive cervical cancer in the Brazilian Amazon region.

INTRODUÇÃO: A diversidade biológica dos estoques Trypanosoma cruzi circulantes na Região Amazônica pode desempenhar importante papel nas características clínico-epidemiológicas peculiares da doença de Chagas nesta área. MÉTODOS: Sete isolados de T. cruzi do Estado do Amazonas provenientes de humanos, mamíferos silvestres e triatomíneos, pertencentes aos genótipos TcI e Z3, foram biologicamente caracterizados em camundongos Swiss. Foram avaliados parâmetros parasitológicos e histopatológicos. RESULTADOS: Quatro isolados não produziram parasitemia patente em camundongos. Três isolados promoveram baixa parasitemia com longos períodos pré-patentes, período patente de um dia ou parasitemia oscilante. A parasitemia máxima variou de 1.400 a 2.800 tripomastigotas/0,1mL de sangue. Os camundongos inoculados com os isolados estudados mostraram baixa positividade no exame a fresco, variando de 0 a 28,6%. Para a hemocultura, a positividade variou de 0 a 100%. Parasitismo cardíaco foi observado em camundongos inoculados com os isolados AM49 e AM61. O isolado AM49 produziu inflamação moderada no tecido cardíaco. Processo inflamatório discreto foi observado no tecido cardíaco de camundongos inoculados com os isolados AM28, AM38, AM61 e AM69. Processo inflamatório em músculo esquelético foi muito frequente. O exame do tecido cerebral revelou focos inflamatórios e gliose em camundongos inoculados com o isolado AM49. CONCLUSÕES: A caracterização biológica e histopatológica demonstrou baixa infecciosidade e virulência dos estoques de T. cruzi isolados no Estado do Amazonas.

INTRODUCTION: The biological diversity of circulating Trypanosoma cruzi stocks in the Amazon region most likely plays an important role in the peculiar clinic-epidemiological features of Chagas disease in this area. METHODS: Seven stocks of T. cruzi were recently isolated in the State of Amazonas, Brazil, from humans, wild mammals, and triatomines. They belonged to the TcI and Z3 genotypes and were biologically characterized in Swiss mice. Parasitological and histopathological parameters were determined. RESULTS: Four stocks did not promote patent parasitemia in mice. Three stocks produced low parasitemia, long pre-patent periods, and a patent period of 1 day or oscillating parasitemia. Maximum parasitemia ranged from 1,400 to 2,800 trypomastigotes/0.1mL blood. Mice inoculated with the T. cruzi stocks studied showed low positivity during fresh blood examinations, ranging from 0% to 28.6%. In hemoculture, positivity ranged from 0% to 100%. Heart tissue parasitism was observed in mice inoculated with stocks AM49 and AM61. Stock AM49 triggered a moderate inflammatory process in heart tissue. A mild inflammatory process was observed in heart tissue for stocks AM28, AM38, AM61, and AM69. An inflammatory process was frequently observed in skeletal muscle. Examinations of brain tissue revealed inflammatory foci and gliosis in mice inoculated with stock AM49. CONCLUSIONS: Biological and histopathological characterization allowed us to demonstrate the low infectivity and virulence of T. cruzi stocks isolated from the State of Amazonas.