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Submitted by Pós graduação Farmácia (ppgfar@ufba.br) on 2017-05-30T20:39:16Z No. of bitstreams: 1 Flavia-Thamires -farmacia-final.pdf: 2671133 bytes, checksum: d04fe328ab695f2547b14e8d937e5959 (MD5) / Approved for entry into archive by Patricia Barroso (pbarroso@ufba.br) on 2017-06-01T17:33:52Z (GMT) No. of bitstreams: 1 Flavia-Thamires -farmacia-final.pdf: 2671133 bytes, checksum: d04fe328ab695f2547b14e8d937e5959 (MD5) / Made available in DSpace on 2017-06-01T17:33:52Z (GMT). No. of bitstreams: 1 Flavia-Thamires -farmacia-final.pdf: 2671133 bytes, checksum: d04fe328ab695f2547b14e8d937e5959 (MD5) / FAPESB / O diagnóstico dos coccídeos Cryptosporidium e Isospora belli é realizado principalmente pela pesquisa de oocistos em esfregaços fecais corados. Entretanto, não existe uma padronização na rotina laboratorial para a identificação microscópica desses coccídeos. O diagnóstico da Cryptosporidium pode também ser realizado pela detecção de coproantígenos por ensaio imunoenzimático (ELISA) ou pela amplificação do DNA através da reação em cadeia da polimerase (PCR), dispensando a identificação morfológica dos oocistos. Além disso, a análise do polimorfismo genético de fragmentos de restrição (PCR-RFLP) pode ser utilizada na caracterização das espécies de Cryptosporidium, permitindo um melhor entendimento da dinâmica da transmissão deste parasito. Os objetivos deste trabalho foram: (1) comparar as técnicas de concentração de formol-acetato de etila (FE) e sedimentação por centrifugação (SC), bem como as técnicas de coloração de Ziehl-Neelsen modificado (ZN), auramina (AR) e safranina (SF) na detecção de oocistos de Cryptosporidium e Isospora belli em amostras fecais; (2) comparar a microscopia com a pesquisa de coproantígeno para o diagnóstico de Cryptosporidium e avaliar os resultados discordantes utilizando a PCR e (3) caracterizar as espécies de Cryptosporidium de amostras fecais humanas, através da PCR-RFLP. Para comparação entre os métodos de concentração de oocistos, FE e SC, e as técnicas de coloração, ZN, AR e SF, foram utilizadas amostras fecais positivas para Cryptosporidium (n=27) e I. belli (n=15), conservadas em formalina a 10%. Os métodos foram avaliados quanto ao número de oocistos detectados e a qualidade microscópica dos esfregaços. Para comparação entre o método de ZN e ELISA para o diagnóstico de Cryptosporidium foram examinadas amostras fecais de 626 crianças de diferentes grupos. Posteriormente, todas as amostras positivas para Cryptosporidium obtidas no estudo, juntamente com outros isolados disponíveis no laboratório, foram submetidos à extração de DNA e análise por Nested-PCR/RFLP dos genes COWP e 18S rRNA, para determinação das espécies de Crptosporidium. Os métodos SC e ZN identificaram mais oocistos de ambos parasitos do que os demais métodos avaliados (p<0,05). Houve perda de oocistos no anel de detritos gordurosos no FE em praticamente todas as amostras de Cryptosporidium e I. belli. Por outro lado, os métodos FE e AR apresentaram menos artefatos nos esfregaços comparados aos demais, sendo classificados com qualidade microscópica superior. A frequência de Cryptosporidium nas crianças foi de 2,6% (16/626), sendo maior no grupo com doença diarreica, enfatizando a importância deste coccídeo como agente etiológico da diarreia infantil. A sensibilidade e especificidade do ELISA foram de 85,7% e 99,7%, respectivamente. A eficiência da amplificação do DNA de Cryptosporidium foi de 92% (23/25), considerando os resultados dos dois genes analisados. As espécies do parasito identificadas foram C. hominis (78,3%), C. felis (8,7%), C. parvum (4,3%) e mistura C. felis + C. hominis (8,7%). Esses dados são os primeiros de genotipagem de Cryptosporidium de indivíduos de Salvador, demonstrando a predominância de C. hominis nas infecções, e a elevada frequência de C. felis, sugerindo um provável papel de gatos na transmissão do parasito aos humanos em nosso meio. / The diagnosis of coccidia Isospora belli and Cryptosporidium is usually accomplished by identification of oocysts in stained fecal smears. However, there is a lack of standardization in the routine laboratory for microscopic identification of these coccidia. The diagnosis of Cryptosporidium can also be done by detecting coproantigens using the enzyme linked immunosorbent assay (ELISA) or by parasite DNA amplification by polymerase chain reaction (PCR), eliminating the need of morphological identification of oocysts. Furthermore, the analysis of restriction fragment length polymorphism of amplified DNA (RFLP-PCR) can be used to characterize the species of Cryptosporidium, allowing a better understanding of the transmission dynamics of the parasite. The objectives of this study were: (1) to compare the techniques of concentration of formalin-ethyl acetate (FE) and sedimentation by centrifugation (SC), as well as the techniques of modified Ziehl-Neelsen (ZN), auramin (AR) and safranin (SF) in the detection of Cryptosporidium and Isospora belli in stool samples, (2) to compare the microscopy with coproantigen detection for the diagnosis of Cryptosporidium and evaluate discordant results using PCR and (3) to characterize the species Cryptosporidium in human fecal samples by PCR-RFLP. To compare the methods for concentration, FE and SC, and staining of oocysts, ZN, AR and SF, there were used positive fecal samples for Cryptosporidium (n = 27) and I. belli (n = 15), preserved in 10% formalin. The methods were evaluated according the numbers of oocysts detected and the microscopic quality of smears. For comparison between ELISA and ZN for the diagnosis of Cryptosporidium in faecal samples, there were examined 626 stool samples from children of different groups. Subsequently, all positive samples for Cryptosporidium obtained in the study, along with other isolates available in the laboratory, were subjected to DNA extraction and analysis by Nested-PCR/RFLP of the COWP and 18S rRNA genes to determine the species of Crptosporidium. The SC and ZN methods identified more oocysts of both parasites than other methods tested (p <0.05). The loss of oocysts in the fatty debris layer of FE method was observed in all Cryptosporidium and I. belli samples. Moreover, the methods of FE and AR had fewer artifacts in smears compared to the others, being ranked with higher microscopic quality. The frequency of Cryptosporidium in children was 2.6% (16/626), being higher in patients with diarrheic disease, emphasizing the importance of this protozoan as etiologic agent of childhood diarrhea. The sensitivity and specificity of ELISA were 85.7% and 99.7%, respectively. The efficiency of amplification of Cryptosporidium DNA was 92% (23/25), considering the results of the two genes. The species of the parasite identified were C. hominis (78.3%), C. felis (8.7%), C. parvum (4.3%) and a mixture of C. felis + C. hominis (8.7%). To our knowledgment, these data represent the first genotyping study of Cryptosporidium from individuals of Salvador, demonstrating the dominance of C. hominis infection and the high frequency of C. felis, suggesting a potential role of cats in the transmission of the parasite to humans in our area.

Thesis (MMed)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The aim of this pilot project was to determine whether mothers with laboratory confirmed or clinically suspected tuberculosis (TB) had evidence of TB in the placenta. A secondary objective was to correlate evidence of placental TB with neonatal outcome. A total of 56 placentas were examined to determine if there were any specific histopathological features predictive of tuberculosis together with Ziehl-Neelsen (ZN) staining. A total of 30 cases were positive for maternal TB and one case was a false positive maternal diagnosis of TB, whilst 25 cases were negative for maternal TB. Biopsies from these 56 placentas were collected for conventional PCR from the paraffin embedded tissue blocks. The performance of these two diagnostic modalities (histopathology and PCR) was assessed coll ectively and individually, and compared to the neonatal outcome (presence or absence of active clinical mycobacterial tuberculosis infection) and evidence of maternal pulmonary and extra pulmonary tuberculosis. The recognition of specific sites of lesions in the placenta (e.g. membranes vs. intervillous space) may lead to an understanding of the pathogenic mechanisms involved in matern alfetal transmission of tuberculosis, and thereby pave the way for further studies in understanding the pathogenesis of congenital TB. Invaluable knowledge was obtained in the diagnoses of M.tuberculosis in the placenta as it was found that micro abscesses and intervillositis were strong indicators of TB infection in the placenta, however, ZN staining still remains the gold standard for diagnosing M.tuberculosis infection in the placenta. PCR is found to have limitations, because only M.tuberculosis DNA is amplified and does not distinguish live from dead bacteria. The conclusion reached is that PCR is of limited value in the diagnosis of active M.tuberculosis infection in the placenta using FFPE tissue, while certain histological changes may be indicative of such infection; however confirmation of the organism by ZN staining is still essential. / AFRIKAANSE OPSOMMING: Die hoofdoelwit van hierdie projek was om vas te stel of moeders met bevestigde of vermoedelike TB enige indikasie van TB in die plasenta toon. ‘n Tweede doelwit was om die neonatale uitkoms teenoor die plasentale TB te korreleer. ‘n Totale getal van 56 plasentas is ondersoek om vas te stel of daar enige spesifieke histopatologiese indikasies is van tuberkulose met die hulp van die ZN spesiale kleuring. Die totale getal positiewe vir TB was 30 asook ‘n vals positiewe geval vir TB en daar was 25 TB negatiewe gevalle. Ses en vyftig biopsies is versamel van paraffien in gebedteerde weefsel vir die gebruik in PKR. Die uitvoering van hierdie twee diagnostiese modaliteite is elk individueel ondersoek asook gesamentlik om dit te vergelyk met die neonatale uitkoms (m.a.w die teenwoordigheid of aanwesigheid van mikobakteriale tuberkulose infeksie) asook die teenwoordigheid van moederlike pulmunere en ekstra-pulmunere tuberkulose. Die spesifieke ligging van die letsels in die plasenta (bv. membrane vs. intervillus spasie) kan lei tot verbeterde begrip van die patogeniese meganismes betrokke in die moeder fetale oordrag van tuberkulose en dit kan lei tot toekomstige navorsing. Waardevolle kennis is opgedoen in die diagnose van M.tuberkulose in die plasenta, want die letsels van mikro abbesses en intervillisitus gee ‘n goeie aanduiding van TB infeksie in die plasenta. Die ZN kleuring bly nog steeds die standaard metode om M.tuberculose in die plasenta te diagnoseer. PKR het baie limiete want dit kan slegs die M.tuberkulose DNA vermeningvuldig, maar dit kan nie onderskeid tref tussen lewendige en dooie bakterie nie. The slotsom in hierdie projek is dat PKR ‘n be pperkte waarde het in die diagnose van aktiewe M .tuberkulose in die plasenta, deur die gebruik van formalien gefikseerde paraffien ingebedteerde weefsel nie terwyl sekere histologiese veranderinge ‘n aa nduiding van sodanige infeksie kan wees maar dat dit deur die spesiale kleruring (ZN) bevestig moet word. / National Health Laboratory Service (NHLS)