Rapid and inexpensive assays for drug susceptibility testing (DST) of Mycobacterium tuberculosis (MTB) are urgently required especially in developing countries where tuberculosis cases are prevalent. In response to this necessity, a direct microplate-based colorimetric assay which excludes the use of pre-testing culture isolate was evaluated. MTB susceptibility to the first line anti-tuberculosis drugs was tested directly on sputum specimens using tetrazolium microplate assay (TEMA) method and the sensitivity, specificity, accuracy as well as mean turn-around time of TEMA were compared to the standard absolute concentration method (ACM). TEMA was performed on 41 acid fast bacilli (AFB) positive sputum specimens by direct inoculation of the processed specimens into the microplate wells containing serialdiluted first line anti-tuberculosis drugs using tetrazolium dye as growth indicator. Indirect TEMA was performed on MTB isolates of the corresponding samples. The minimum inhibitory concentrations (MICs) of isoniazid (INH), rifampicin (RMP), ethambutol (EMB) and streptomycin (SM) were obtained for direct and indirect TEMA with reference to the absolute concentration method (ACM). After establishing the breakpoint MIC of each drug using receiver operating characteristics (ROC) curve, reliable results from direct TEMA were obtained for INH and SM, with excellent levels of sensitivity, specificity, and accuracy (more than 90%). The predictive values for susceptibility were 100% for INH, EMB and SM as well as 96% for RMP. A shorter mean turn-around time of 14 days was observed for direct TEMA (P < 0.05). Thus direct TEMA is potentially rapid, reliable and inexpensive DST screening method of MTB in countries with high prevalence rates of drug resistance tuberculosis

Antimicrobial activities of plants have long been evaluated for their promising use as antimicrobial agent and in minimizing the unwanted resistance effects of microorganisms. The study was conducted to evaluate the antibacterial activity of Quercus infectoria gall crude extracts against multidrug resistant (MDR) bacteria in vitro. The screening test was determined by disc diffusion technique using sterile filter paper discs impregnated with 1 mg/ disc (50 mg/ml) aqueous and ethanol extracts of Q. infectoria galls tested on five selected MDR bacterial strains. The minimum inhibitory concentration (MIC) was determined using the twofold serial micro dilution technique at concentration ranging from 5.00 mg/ml to 0.01 mg/ml. The minimum bactericidal concentration (MBC) was determined by sub culturing the microtitre wells showing no turbidity on the agar plate to obtain the MBC value. Both extracts showed substantial inhibitory effects against methicillin resistant coagulase negative Staphylococcus (MRCoNS) and methicillin resistant Staphylococcus aureus (MRSA). A slightly reduced inhibitory zone diameter was observed with MDR Acinetobacter sp. while no inhibitory effect was displayed among the extended spectrum beta lactamases (ESBL) K. pneumoniae and ESBL E. coli isolates. A significant difference in the zone sizes between both extracts was only observed in MRSA (p < 0.05). The MIC values ranged from 0.08 mg/ml to 0.63 mg/ml for aqueous and ethanol extracts against MRSA, MRCoNS and MDR Acinetobacter sp. while their MBC to MIC ratio values were 2 and less. The Q. infectoria gall extracts have shown very promising in vitro antibacterial activities and may be considered as a potentially good source of antimicrobial agent especially against MDR Gram positive bacteria.

Abstract. The use of ice cubes in beverages is common among patrons of food outlets in Malaysia although its safety for human consumption remains unclear. Hence, this study was designed to determine the presence of faecal coliforms and several useful water physicochemical parameters viz. free residual chlorine concentration, turbidity and pH in ice cubes from 30 randomly selected food outlets in Kubang Kerian, Kelantan. Faecal coliforms were found in ice cubes in 16 (53%) food outlets ranging between 1 CFU/100mL to >50 CFU/ 100mL, while in the remaining 14 (47%) food outlets, in samples of tap water as well as in commercially bottled drinking water, faecal coliforms were not detected. The highest faecal coliform counts of >50 CFU/100mL were observed in 3 (10%) food outlets followed by 11-50 CFU/100mL and 1-10 CFU/100mL in 7 (23%) and 6 (20%) food outlets, respectively. All samples recorded low free residual chlorine concentration (<0.10mg/L) with the pH ranging between 5.5 and 7.3 and turbidity between 0.14-1.76 NTU. Since contamination by faecal coliforms was not detected in 47% of the samples, tap water and commercially bottled drinking water, it was concluded that (1) contamination by faecal coliforms may occur due to improper handling of ice cubes at the food outlets or (2) they may not be the water sources used for making ice cubes. Since low free residual chlorine concentrations were observed (<0.10mg/L) in all samples as well as in both tap water and commercially bottled drinking water, with the pH ranged between 5.5-7.3, ineffective disinfection of water source as a contributing factor to such high counts of faecal coliforms in ice cubes also could not be ruled out. Therefore, a periodical, yet comprehensive check on the food outlets, including that of ice cube is crucial in ensuring better food and water for human consumption.

Clinical utilization of carbapenems remains under threat with the emergence of acquired carbapenemase-producing bacteria, particularly metallo-β-lactamases (MBL). Rapid detection of MBL-producing Gram-negative bacilli is essential to prevent their widespread dissemination. However, no standardized detection method is available for routine laboratory use. The purpose of the study was to evaluate a chelating-agent based double disk synergic test and disk potentiation test for MBL-producing strain detection and to determine the isolation rate of MBL-producing Pseudomonas aeruginosa and Acinetobacter from clinical samples in our tertiary teaching hospital. A total of 22 and 66 imipenem-resistant P. aeruginosa and Acinetobacter isolates respectively were tested with ceftazidime (CAZ) disk by modified double disk synergic test and disk potentiation test using ethylenediaminetetraacetic acid (EDTA) and 2-mercaptopropionic acid (as chelating agents) to detect MBL production. The tests were compared with EDTA-phenanthroline-imipenem (EPI) microdilution MIC test as gold standard. MBL positive strains were detected in 17 (77.3%) P. aeruginosa and 2 (3.5%) Acinetobacter isolates. The disk potentiation test with 2-mercaptopropionic acid (2-MPA) dilution of 1:12 provided the most acceptable sensitivities and specificities (88.2% sensitivity and 100% specificity in P. aeruginosa; 100% sensitivity and specificity in Acinetobacter) compared to other screening methods used in this study. This study provided useful informationon the local prevalence of MBL-producing P. aeruginosa and Acinetobacter in our hospital. Disc potentiation test with CAZ/2-MPA disc appears to be reliable and convenient MBL detection method in the routine clinical laboratory.

Human fascioliasis is a public health problem particularly in areas where ruminants are raised. The aims of this study were to determine the seroprevalence of anti-Fasciola antibody and the associated risk factors among cattle farm workers and dwellers in Kelantan. A total of 90 blood samples were collected in this cross-sectional study. A set of validated questionnaire was used to obtain information on socio-demographic profiles and dietary habits of participants. The sera were subjected to enzyme linked immunosorbent assay (ELISA) for the detection of anti-Fasciola IgG antibody. The association between seropositivity and the significant risk factors were determined via logistic regression. From the result, serological screening revealed 60 (67%) participants positive for anti-Fasciola IgG antibody. The factors found to be significantly associated with seropositivity against anti-Fasciola IgG antibody were the age group of 18 years old and above with calculated odds ratio of 3.2 times (p=0.032) and the duration of farming activities of more than 5 years with calculated odds ratio of 2.6 times (p=0.036). In conclusion, Fasciola infection is prevalent among cattle farm workers and dwellers in Kelantan.