The relationship between bacterial sources and genotype to the antimicrobial resistance pattern of Burkholderia pseudomallei.

BACKGROUND: Melioidosis is a fatal emerging infectious disease of both man and animal caused by bacteria Burkholderia pseudomallei. Variations were suggested to have existed among the different B. pseudomallei clinical strains/genotypes which may implicate bacterial susceptibility and resistance toward antibiotics. AIM: This study was designed to determine whether the phenotypic antibiotic resistance pattern of B. pseudomallei is associated with the source of isolates and the genotype. MATERIALS AND METHODS: A collection of 111 B. pseudomallei isolates from veterinary cases of melioidosis and the environments (soil and water) were obtained from stock cultures of previous studies and were phylogenetically characterized by multilocus sequence typing (ST). The susceptibility to five antibiotics, namely meropenem (MEM), imipenem, ceftazidime (CAZ), cotrimoxazole (SXT), and co-amoxiclav (AMC), recommended in both acute and eradication phases of melioidosis treatment were tested using minimum inhibitory concentration antibiotics susceptibility test. RESULTS: Majority of isolates were susceptible to all antibiotics tested while few resistant strains to MEM, SXT, CAZ, and AMC were observed. Statistically significant association was found between resistance to MEM and the veterinary clinical isolates (p<0.05). The likelihood of resistance to MEM was significantly higher among the novel ST 1130 isolates found in veterinary cases as compared to others. CONCLUSION: The resistance to MEM and SXT appeared to be higher among veterinary isolates, and the novel ST 1130 was more likely to be resistant to MEM as compared to others.

Phylogenetic Diversity of Burkholderia pseudomallei isolated from veterinary cases and the environments in Peninsular Malaysia.

This study was designed to determine the genotype and the phylogeny of Burkholderia pseudomallei isolated from veterinary cases and from the animal environments in Peninsular Malaysia. The Malaysian B. pseudomallei population were then compared to those found elsewhere. A total of 113 isolates from veterinary cases (35) and the environment (56 from soil and 22 from water) were characterized using multilocus sequence typing (MLST). Two novel alleles, allele 97 and 69 of the gene locus ace and lepA respectively were recovered. Isolates were resolved into 12 distinct sequence types (STs) out of which five were novel, namely ST1130, ST1131, ST1338, ST1339 and ST1367. The isolates from veterinary cases co-clustered with those from the environment. B. pseudomallei isolates in this study were highly clonal and have descended from a common ancestor clonal complex (CC) 48 found in Southeast Asia. This study shows that veterinary case isolates are often caused by similar STs, with similar populations found in the direct animal environment and those previously reported to cause human infections in Malaysia and elsewhere. Isolates of B. pseudomallei from human infections have been given more attention, with a comparatively lower focus on isolates from animals and the farm environment. This study highlighted the genotype and phylogeny of B. pseudomallei isolated from animals and the environment and their relations to the isolates from human cases reported in Malaysia and elsewhere. Most STs reported in this study, from veterinary cases and animal environment are similar to those previously reported as causing human infections in Malaysia and elsewhere. Therefore, even though direct zoonosis is uncommon, monitoring melioidosis occurrences in animals can provide insights on the bacterial strains infecting humans.

Variable presentation of retrocaval ureter: Report of four cases and review of literature.

Retrocaval ureter is a rare anomaly in which the ureter passes behind the inferior vena cava due to abnormal embryogenesis. Very few cases have been reported from Africa. Although the anomaly is congenital, patients become symptomatic in the third or fourth decade of life. We reviewed the records of four patients with the diagnosis of retrocaval ureter and managed in our centre between January 2010 and December 2016. Three patients presented with recurrent colicky right flank pain while one was asymptomatic. Two patients each had Type I and Type II retrocaval ureters, respectively. Surgical repairs were achieved in the three symptomatic cases and recovery was uneventful. Retrocaval ureter, though congenital, manifests in young adults and it may be symptomatic. Pre-operative diagnosis may be difficult when the lesion is high and mimics pelviureteric junction obstruction. Thus, a high index of suspicion is required for pre-operative diagnosis. Under-reporting and asymptomatic cases may account for the low incidence.

In vitro larvicidal effects of ethanolic extract of Curcuma longa Linn. on Haemonchus larval stage.

AIM: Gastrointestinal helminthosis is a global problem in small ruminant production. Most parasites have developed resistance to commonly available anthelminthic compounds, and there is currently an increasing need for new compounds with more efficacies. This study evaluated the in vitro effects of ethanolic extract of Curcuma longa (EECL) as a biological nematicide against third stage Haemonchus larvae (L3) isolated from sheep. MATERIALS AND METHODS: Haemonchus L3 were cultured and harvested from the feces of naturally infected sheep. EECL was prepared and three concentrations; 50, 100, and 200 mg/mL were tested for their efficacies on Haemonchus L3. Levamisole at concentration 1.5 and 3 mg/mL were used as positive controls. RESULTS: EECL showed anthelmintic activity in a dose-dependent manner with 78% worm mortality within 24 h of exposure at the highest dose rate of 200 mg/mL. There was a 100% worm mortality rate after 2 h of levamisole (3 mg/mL) admisntration. However, there was a comparable larvicidal effect between when levamisole (1.5 mg/mL) and EECL (200 mg) were administered. CONCLUSION: The study shows that EECL does exhibit good anthelmintic properties at 200 mg/mL which is comparable with levamisole at 1.5 mg/mL.

The use of FAMACHA in estimation of gastrointestinal nematodes and total worm burden in Damara and Barbados Blackbelly cross sheep.

The prevalence of gastrointestinal (GI) nematodes and total worm burden of Damara and Barbados Blackbelly cross sheep was investigated among smallholder farms in Salak Tinggi district of Selangor, Malaysia. A total of 50 sheep raised in smallholder farms comprising of 27 Damara cross and 23 Barbados Blackbelly cross were categorized based on their age into young and adults. Fecal samples were collected and examined for strongyle egg count by using modified McMaster technique. Severity of infection was categorized into mild, moderate, and heavy, based on egg per gram (EPG). Five sheep were randomly selected and slaughtered to examine the presence of adult gastrointestinal (GI) nematodes through total worm count (TWC). Faffa Malan Chart (FAMACHA) score was used for investigation of worm load based on the degree of anemia. The study revealed an overall EPG prevalence of 88 %, of which 84.1 % had mild infection. There was a significant difference (p = 0.002) in EPG among the two breeds. Based on age, significant difference (p = 0. 004) in EPG was observed among Barbados Blackbelly cross, but not for Damara cross (p = 0.941). The correlation between severity of infection and the FAMACHA score was significant (r = 0.289; p = 0.042). Haemonchus spp. were the most predominant nematode found in the gastrointestinal tract, followed by Trichostrongylus and Oesophagostomum spps. EPG and TWC for Haemonchus were positively correlated, but not significant (r = 0.85, p = 0.066). From regression analysis, 73 % of the variability in TWC for Haemonchus could be explained by EPG. Thus, it can be concluded that FAMACHA score correlates well with severity of infection of a nematode and can be used to assess the strongyle nematode burden in the different sheep crosses.