Ocorrência de Cryptococcus neoformans em excretas de pombos na cidade de Pelotas, Estado do Rio Grande do Sul

Abstract

RESUMOIntrodução: O Cryptococcus neoformans é uma levedura capsulada, agente etiológico da criptococose em humanos e animais, encontrado em fontes ambientais, incluindo excretas de pombos, é uma importante causa de mortalidade em indivíduos imunodeprimidos em todo o mundo. Métodos: com o objetivo de verificar a ocorrência do Cryptococcus neoformans, em excretas de pombos, na cidade de Pelotas, pesquisou-se 70 ambientes, incluindo prédios, praças e locais ao ar livre, da cidade de Pelotas, RS. Após a coleta, os excrementos foram adicionados de salina com cloranfenicol, homogeneizados, semeados em ágar Sabouraud com cloranfenicol e ágar Níger e incubados a 32ºc. Para identificação, realizou-se exame direto, prova da fenoloxidase, urease, assimilação de carboidratos e cultura em meio cGB. Resultados: Dos locais estudados (nº =70), em 26 (37,1%) havia excretas de pombos. Estes lugares foram representados por prédios históricos (nº =8), torre de igreja (nº =1), engenhos e armazéns de arroz (nº =7), praça (nº =1) e locais ao ar livre (nº =9), o isolamento de Cryptococcus neoformans ocorreu em 26,9% (nº =7/26), destes locais. Conclusões: O estudo chama a atenção, para o isolamento do fungo em áreas urbanas, que apresentavam grande acúmulo de excretas, indicando um risco para a saúde pública, especialmente para indivíduos imunocomprometidos. Palavras-chaves: Cryptococcus neoformans. Excretas. Pombos. Ambiente. Urbano. ABSTRACT Introduction:Cryptococcus neoformans is an encapsulated yeast and is the etiological agent for human and animal cryptococcosis. It is found in sources within the environment, including pigeon excrement, and is an important cause of mortality among immunocompromised individuals worldwide. Methods: Seventy different environments in the city of Pelotas, Rio Grande do Sul, were surveyed for the purpose of investigating Cryptococcus neoformans occurrences in pigeon excreta. The environments included buildings, public squares and outdoor locations in the city. After collection, chloramphenicol saline solution was added to the excreta, which were then homogenized and seeded onto Sabouraud agar with chloramphenicol and onto Niger agar, and incubated at 32°c. Identification was performed by direct examination and by means of the phenoloxidase and urease tests, carbohydrate assimilation and culturing in cGB medium. Results: Out of the sites investigated (n = 70), 26 (37.1%) of them contained pigeon excreta. These included historical buildings (n = 8), a church tower (n = 1), rice mills and warehouses (n = 7), a public square (n = 1) and outdoor locations (n = 9). Cryptococcus neoformans was isolated from 26.9% (n = 7/26) of these locations. Conclusions: This study draws attention to isolation of this fungus in urban areas that present large accumulations of pigeon excrement. This represents a risk to public health, especially for immunocompromised individuals.

Survey of Cryptococcus neoformansin pigeon (Columba livia) excreta in Public Square in Umuarama, Paran, Brazil

“…in pigeon excreta, the positivity in our study was low in relation to similar studies performed in Brazil. In the southern region, Reolon et al (2004) detected the fungus in 100% of the samples in Porto Alegre and Faria et al (2010) recorded positivity of 26.9% in environmental samples in Pelotas. Abegg et al (2006) analyzed excreta from 59 captivity bird species kept in cages in a zoo in Rio Grande do Sul, where the birds belonged to 12 different orders, 38 samples found positive for C. neoformans in environments with Psittaciformes.…”

“…C. gattii has a stricter distribution, being usually associated to tropical and subtropical areas (Boekhout et al, 2001). Studies show a variation in the isolation of C. neoformans from pigeon excreta ranging from 24.7 to 4.6% (Faria et al, 2010).…”

FIRST REPORT ON Cryptococcus neoformans IN PIGEON EXCRETA FROM PUBLIC AND RESIDENTIAL LOCATIONS IN THE METROPOLITAN AREA OF CUIABÁ, STATE OF MATO GROSSO, BRAZIL

“…However, when considering studies that examined samples of pigeon excreta, positivity rates for the isolation of the fungus in Brazil ranged from 4.3 to 31.3% 3 6 9 13 16 23 27 28 29 31 34 37 39 . The findings of this study show a positivity rate of 12% for C. neoformans , values that are compatible with the rates of isolation in Brazil previously reported in the literature.…”

“… 9 evaluated 70 environments, including squares (n = 1), historic buildings (n = 8), church towers (n = 1), rice mills and warehouses (n = 7) and outdoor locations (n = 9). Considering all these sites, the isolation of C. neoformans was verified in 26.9% (n = 7/26).…”

Cryptococcus spp. em excretas de Columba livia (pombos domésticos) provenientes de um hospital universitário no Sul do Brasil

“…O fungo C. neoformans tem distribuição mundial e seu habitat natural são as excretas de aves, especialmente de Columba livia (pombos domésticos) (Faria et al, 2010). Por outro lado, C. gattii ocorre em regiões tropicais e subtropicais, e tem como habitat natural os eucaliptos e material vegetal em decomposição.…”