ABSTRACT
Abstract The aim of the present study was to evaluate the growth rate of Balantidium coli in three xenic media cultures. Between 2013 and 2015, 10 B. coli isolates obtained from feces of Cynomolgus macaques, and 30 isolates from feces of pigs were studied. An inoculum of 500 trophozoites was transferred to tubes containing LES, TYSGM-9 and Pavlova media. These cultures were evaluated at incubation times of 24, 48, 72 and 96 hours. In most of strains analyzed wasn't showed significant difference in the growth rate comparing TYSGM-9 and Pavlova media (Wilcoxon p>0.016). In Pavlova medium, the trophozoites showed a maximum growth at 72 hours with significant difference when compared with the times of 24 h and 96 h (Wilcoxon <0.008). In LES, viable trophozoites were observed until 24 hours, with a significant difference (Friedman p<0.05, Wilcoxon p<0.016) in the number of parasite cells compared with Pavlova and TYSGM-9 media cultures. Thus, LES medium seemed to be less adequate than the other media for maintenance of B. coli. Despite the satisfactory results in TYSGM-9, Pavlova medium was considered ideal for the maintenance of this protozoan strain, guaranteeing the viability of the parasite with subculture every three days, presenting lower costs.
Resumo O objetivo do presente estudo foi avaliar a taxa de crescimento de Balantidium coli em três meios de cultura xênicos. Entre 2013 e 2015 foram estudados 10 isolados de B. coli obtidos de Cynomolgus macaques e 30 isolados de suínos. Um inóculo contendo 500 trofozoítos foi transferido para tubos contendo os meios LES, TYSGM-9 e Pavlova. Os cultivos foram avaliados com tempos de incubação de 24, 48, 72 e 96 horas. Na maioria das cepas analisadas não foi observado diferença significativa na taxa de crescimento comparando TYSGM-9 e Pavlova (Wilcoxon p>0,016). Em Pavlova, os trofozoítos apresentaram máximo de crescimento a 72 h com diferença significativa quando se comparou com os tempos de 24 h e 96 h (Wilcoxon <0,008). Em LES observou-se trofozoítos viáveis até 24 horas com diferença significativa (Friedman p<0,05 e Wilcoxon p<0,016), na quantidade de células parasitárias, quando comparado com Pavlova e TYSGM-9. Dessa forma, o meio LES mostrou-se ser menos adequado do que os outros, para a manutenção de B. coli. Apesar do resultado satisfatório em TYSGM-9, Pavlova foi considerado ideal para manutenção do protozoário, por garantir a viabilidade do parasito com subcultivos a cada três dias, além de apresentar menor custo.
Subject(s)
Animals , Balantidium/growth & development , Culture Media , Parasitology/methods , Swine/parasitology , Balantidium/isolation & purification , Macaca/parasitologyABSTRACT
Introduction: Blastocystis hominis (B. hominis) is an obligate anaerobic protozoan found in the human large intestine, and is the most common eukaryotic organism reported in human fecal samples. Method: Multiple stool samples from 460 children (53.9% male and 46.07% female) were collected and examined for the presence of Blastocystis hominis in Parasitology Laboratory of International Centre for Diarrhoeal Diseases Research, Bangladesh during the period of 9th January to 28th December, 2011. Among them, 255 were diarrheal patients (56.47% male and 43.53% female). Direct microscopy was done for each of the samples and each sample was cultured in vitro for 48 hours and observed again for the presence of the pathogen. Th e aim of the study was to develop a sustainable technique to identify the pathogen. Results: In culture, several morphological forms were observed. Th rough microscopy, various morphological forms were clearly observed. Within 5679 tested samples, 795 samples (0.14%) were positive for B. hominis. As multiple forms were observed in the same sample, the most prevalent was cyst (0.125%) whereas least prevalent was granular (0.0072%). Th e highest percentage for all the morphological forms was observed in age group 25-36 months. In direct microscopy from fresh samples, children from 37-48 months showed the highest percentage (22.9%) of infection (p=0.000). In culture, the same age group showed the most infection rate (p=0.000). Among the diff erent morphological forms observed in culture, the highest prevalence of cyst was in age group 37-48 months (p=0.000). Th e highest prevalence of vacuolar form(5.7%) was observed in the same age group (p=0.015). In contrast, the amoeboid forms were mostly observed in children of 25-36 months (p=0.002).Th e children aged in between 37 to 48 months are at the most risk of the infection. Conclusion: Th e sensitivity of direct microscopy was found only 38.46% in respect to in-vitro culture which strongly suggests that in-vitro culture is the gold standard for the diagnosis of this parasite.