Antimicrobial resistance among the bacteria present in ready-to-eat foods like vegetable salads is an emerging concern today. The current study was undertaken to investigate the presence of multi-drug resistant extended-spectrum β-lactamase (ESBL) producing E. coli and Salmonella spp. in raw vegetable salads served at hotels and restaurants in Bharatpur. A total of 216 salad samples were collected from three different grades of hotels and restaurants and examined for the presence of E. coli and Salmonella spp. in Microbiology laboratory of Birendra Multiple Campus by conventional microbiological techniques. Out of 216 samples, 66 samples (35.2%) showed the presence of Salmonella spp. whereas E. coli was recovered from 29 (13.4%) samples of which 3 samples harbored E. coli O157: H7. Antibiotic susceptibility testing revealed that 9 (13.6%) Salmonella and 4 (13.8%) E. coli isolates were detected as multi-drug resistant. Total ESBL producers reported were 5 (7.57%) Salmonella and 4 (13.8%) E. coli. The study also assessed a significant association between occurrence of E. coli and Salmonella with different grades of hotels and restaurants, personal hygiene and literacy rate of chefs and with the type of cleaning materials used to wash knives and chopping boards (p < 0.05). The findings suggest an immediate need of attention by the concerned authorities to prevent the emergence and transmission of food-borne pathogens and infections antimicrobial resistance among them.
The emergence of multidrug resistant (MDR) bacteria which is attributable to extended spectrum β‐lactamases (ESBLs) production of CTX‐M types is an obvious problem worldwide. This study is aimed at determining the prevalence of CTX‐M β‐lactamases producing multidrug resistant Escherichia coli and Klebsiella pneumoniae among patients attending Bir Hospital. A cross‐sectional study was conducted between April and September 2019 at Bir Hospital, Kathmandu, and Department of Microbiology, National College, Kathmandu, Nepal. A total of 5,690 different clinical specimens were subjected to cultural, microscopic, and biochemical analyses for the identification of the isolates. Antimicrobial susceptibility testing of the isolates was done, and MDR isolates were selected and processed for further ESBL confirmation by the combination disks method. All confirmed ESBL isolates were screened for CTX‐M type β‐lactamases (blaCTX-M) by PCR. Of the total 345 isolates (227 Escherichia coli and 118 Klebsiella pneumoniae), 232 were MDR. All 232 (67.24%) MDR isolates were suspected as ESBL producers on the screening test. However, on the phenotypic test, 135 (58.18%) of total MDR bacteria were confirmed as ESBL producers with the highest proportion in K. pneumoniae (59.37%). The major source of ESBL producers was urine. ESBL producing isolates were mostly identified from outpatients and patients belonging to age group 41‐60. Gentamicin was found to be effective against ESBL producers. The prevalence of blaCTX-M was (89.62%) with the highest frequency for E. coli (93.81%). High prevalence of ESBL of CTX‐M types among MDR E. coli and K. pneumoniae was detected from clinical specimens of patients in Bir Hospital. This study warrants the need for the judicious use of antibiotics as well as emphasize the use of modern diagnostic tools for the early detection of MDR and ESBL producers to curb the emergence and spread of MDR and ESBL producing bacteria in the clinical settings of Nepal.
Objective: The current study aims to explore the bacteriology of sputum of tuberculosis (TB) suspected patients. A cross-sectional study was carried out in the sputum samples of 150 TB suspected patients visiting District Public Health Office, Bharatpur, Nepal. The samples were subjected to cultural, microscopic and biochemical analyses for the identification of the isolates. In addition, antibiotic susceptibility tests were carried out with a special focus on ESBL and MBL production following Clinical and Laboratory Standard Institute guidelines.Results: Bacterial growth was recovered in 47% (71/150) of the TB suspected patients of which 12.66% (19/150) had pulmonary TB infection.Streptococcusspp. (9%) andPseudomonas aeruginosa(9%) were the most frequently isolated bacteria. Enterobacteriaceae accounted for 35% of the total isolates. Occurrence of bacterial pathogens was more in males (69%) than in females (31%).The incidence of bacterial pathogen was seen associated with gender of the patients and with the TB infection (p < 0.05) but independent with age of the patients and HIV infection (p > 0.05). Tetracycline was effective againstStreptococcusspp. whereas gentamicin was effective againstBacillusspecies. Imipenem and co-trimoxazole were effective drugs for Gram-negative isolates. Among 83 isolates, 35 were multi-drug resistant, 9 were ESBL producers and 4 were MBL producers.
Microbially produced gamma poly glutamic acid (γ–PGA) is a commercially important biopolymer with many applications in foods and various other substances and are abundantly used in different parts of the world. With an aim to study the potent γ–PGA producing Bacillus species, a total of 47 different samples (Kinema, soil, and water) were randomly collected from different locations across the country, and Bacillus sp. were selectively isolated, screened, and characterized by performing physiological, biochemical, morphological, and 16S rRNA gene sequencing. The microbial production of γ–PGA was assayed with the selected isolates on the PGA medium and the metabolite obtained was recovered by ethanol precipitation method and further characterized by thin-layer chromatography (TLC). Thermotolerance (25–60 °C), pH tolerance (4–9), and NaCl tolerance (1–9%) tests were performed to optimize the bacterial growth and γ–PGA production and its viscosity were measured by Ostwald's viscometer. Out of 145 randomly selected colonies, 63 isolates were Gram-positive, rods, and endospore producers and were presumptively confirmed as genus Bacillus. Higher growth of γ–PGA producers were reported in 22 isolates and was found at optimum conditions such as temperature (30–37 °C), pH (6.5–7), incubation time (3 days), and NaCl concentration (3%) and γ–PGA thus produced was further verified by TLC with the retention factor (RF) value 0.27. The potent isolates were closely similar to Bacillus subtilis subsp. stercoris, Bacillus cereus, Bacillus paranthracis, and Bacillus licheniformis etc. Based on the findings of the study, B. licheniformis is the most potent γ–PGA producing Bacillus sp. which can further be used for the commercial production of γ–PGA. To the best of our knowledge, there is yet no published research from Nepal showing the production of the γ–PGA although microbially produced γ–PGA are the major constituents in some popular foods in particular communities of the country.
29 October 2021 in Emergency Medicine International
The multidrug- or extensively drug-resistant (MDR/XDR) Pseudomonas aeruginosa carrying some virulence genes has become a global public health threat. However, in Nepal, there is no existing report showing the prevalence of oprL and toxA virulence genes among the clinical isolates of P. aeruginosa. Therefore, this study was conducted for the first time in the country to detect the virulence genes (oprL and toxA) and antibiotic susceptibility pattern of P. aeruginosa. A total of 7,898 clinical specimens were investigated following the standard microbiological procedures. The antibiotic susceptibility testing was examined by the modified disc diffusion method, and virulence genes oprL and toxA of P. aeruginosa were assessed using multiplex PCR. Among the analyzed specimens, 87 isolates were identified to be P. aeruginosa of which 38 (43.68) isolates were reported as MDR. A higher ratio of P. aeruginosa was detected from urine samples 40 (45.98), outpatients specimens 63 (72.4), and in patients of the age group of 6079 years 36 (41.37). P. aeruginosa was more prevalent in males 56 (64.36) than in female patients 31 (35.63). Polymyxin (83.90) was the most effective antibiotic. P. aeruginosa (100) isolates harboured the oprL gene, while 95.4 of isolates were positive for the toxA gene. Identification of virulence genes such as oprL and toxA carrying isolates along with the multidrug resistance warrants the need for strategic interventions to prevent the emergence and spread of antimicrobial resistance (AMR). The findings could assist in increasing awareness about antibiotic resistance and suggest the judicious prescription of antibiotics to treat the patients in clinical settings of Nepal.
A urine dipstick test used for prompt diagnosis of urinary tract infection (UTI) is a rapid and cost-effective method. The main objective of this study was to compare the efficacy of the urine dipstick test with culture methods in screening for UTIs along with the detection of the blaCTX-M gene in extended spectrum β-lactamase (ESBL)-producing Escherichia coli. A total of 217 mid-stream urine samples were collected from UTI-suspected patients attending Bharatpur Hospital, Chitwan, and tested by dipstick test strip (COMBI-10SL, Germany) prior to the culture. E. coli isolates were identified by standard microbiological procedures and subjected to antimicrobial susceptibility testing by Kirby Bauer disc diffusion method following CLSI guideline. Primary screening of ESBL-producing E. coli isolates was conducted using ceftriaxone, cefotaxime and ceftazidime discs and phenotypically confirmed by combined disk diffusion test. Plasmid DNA of ESBL-producing strains was extracted by phenol-chloroform method and subjected to PCR for detection of the blaCTX-M gene. Out of 217 urine samples, 48 (22.12%) showed significant bacteriuria. Among 46 (21.20%) Gram negative bacteria recovered, the predominant one was E. coli 37 (77.08%) of which 33 (89.19%) were multidrug resistant (MDR). E. coli isolates showed a higher degree of resistance towards cefazolin (62.16%) while 81.08% of the isolates were sensitive towards amikacin followed by nitrofurantoin (70.27%). Among 14 (37.84%) phenotypically confirmed ESBL isolates, only eight (21.62%) isolates carried the blaCTX-M gene. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of urine dipstick test were 43.75%, 77.51%, 35.59% and 82.91%, respectively. Besides, the use of dipstick test strip for screening UTI was associated with many false positive and negative results as compared to the gold standard culture method. Hence, dipstick nitrite test alone should not be used as sole method for screening UTIs.