High carriage rates of extended-spectrum beta-lactamase-producing enterobacteriaceae in children at admission into paediatric wards of a university teaching hospital in Lagos, Nigeria.

CONTEXT: Bowel carriage has been identified as the main reservoir of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) and hospital-acquired infections. There are gaps in the knowledge of trends of these rates, which need to be filled for the development and implementation of hospital surveillance systems and antibiotic stewardship programmes in Nigeria. AIM: This study investigated the carriage rates of ESBL-PE among 273 children admitted to the paediatric wards of a university teaching hospital, Nigeria, using a prospective cohort study design over a 6-month period. SETTINGS AND DESIGN: The study explored the role of new and transferred patients in introducing resistant strains of ESBLs into paediatric wards and how quickly paediatric patients that were previously free of resistant strains acquired these within the hospital environment. MATERIALS AND METHODS: E-swabs (Copan Diagnostics, Italy) were used to obtain rectal samples from participants. Positive colonies were Gram stained and subcultured onto purity plates for further identification, and antibiotic susceptibility pattern of identified ESBL-PE was obtained using a range of antibiotics. STATISTICAL ANALYSIS USED: Data were analysed using SPSS statistics 20 (IBM SPSS Statistics, version 20). Statistical significance was determined using the Chi-square test and Fisher's exact test. A logistic regression analysis was also conducted to identify independent risk factors for colonisation. RESULTS: The findings showed that transferred patients contributed to the introduction of ESBLs into the hospital. Independent multivariate risk factors for colonisation of ESBL-PE were age >10-14 years, instrumentation (odds ratio [OR]: 0.2 [P < 0.05]) and sharing of thermometers (OR: 0.11 [P < 0.05]). CONCLUSIONS: The carriage rate of ESBL-PE is high (25.3%) among children, and none-carriers may become colonised within 14 days of hospitalisation.

Molecular diversity and antibiotic resistance gene profile of Salmonella enterica serovars isolated from humans and food animals in Lagos, Nigeria.

Outbreaks of Salmonellosis remain a major public health problem globally. This study determined the diversity and antibiotic resistance gene profile of Salmonella enterica serovars isolated from humans and food animals. Using standard methods, Salmonella spp. were isolated from fecal samples, profiled for antimicrobial susceptibility and resistance genes. Seventy-one Salmonella isolates were recovered from both humans and food animals comprising cattle, sheep, and chicken. Forty-four serovars were identified, with dominant Salmonella Budapest (31.8%). Rare serovars were present in chicken (S. Alfort, S. Wichita, S. Linton, S. Ealing, and S. Ebrie) and humans (S. Mowanjum, S. Huettwillen, S. Limete, and S. Chagoua). Sixty-eight percent of isolates were sensitive to all test antibiotics, while the highest rate of resistance was to nalidixic acid (16.9%; n = 12), followed by ciprofloxacin (11.3%; n = 8) and tetracycline (9.9%; n = 8). Five isolates (7%) were multidrug-resistant and antimicrobial resistance genes coding resistance to tetracycline (tetA), beta-lactam (blaTEM), and quinolone/fluoroquinolone (qnrB and qnrS) were detected. Evolutionary analysis of gyrA gene sequences of human and food animal Salmonella isolates revealed variations but are evolutionarily interconnected. Isolates were grouped into four clades with S. Budapest isolate from cattle clustering with S. Budapest isolated from chicken, whereas S. Essen isolated from sheep and chicken was grouped into a clade. Diverse S. enterica serovars with high antibiotic resistance profile are ubiquitous in food animals; hence, there is a need for surveillance and prudent use of antibiotics in human and veterinary medicine.

Feasibility and cost analysis of programmatic implementation of Microscopic-Observation Drug Susceptibility (MODS) assay in Nigeria.

Objectives: Detection of Multi-drug resistant tuberculosis in Nigeria still remains a challenge. We evaluated the feasibility of programmatic implementation of the Microscopic-Observation Drug Susceptibility (MODS) assay, a rapid culture and drug susceptibility testing technique for drug susceptibility testing in a low resource setting. Method: In a novel laboratory setting in Nigeria, we obtained data from the market on the cost of materials necessary for MODS assay. Three routinely collected sputum specimens from 160 tuberculosis suspects were evaluated by smear microscopy while only the early morning specimen was used for MODS culture. Results: MODS assay detected M. tuberculosis in 97.7% (42/43) of smear positive and 6.0% (7/117) of smear negative TB suspects. There was a statistically significant advantage of a single MODS culture over 3 smear microscopies (P=0.019). The modal time from culture of specimen to detection of M. tuberculosis and availability of drug susceptibility result for MODS was 7days with a mean of 8.4 days (Range= 5-13 days). Culture and susceptibility result was available in 18.4% (9/49) of patients within 5days of culture. Turnaround time for smear microscopy in the centers was 3 days. Cost of processing one specimen by MODS assay in the study was USD2.65. Multi-Drug resistant tuberculosis (MDR-TB) was detected in 4.1% (2/49) while Isoniazid mono-resistance was detected in 2.0% (1/49) of the culture positive cases. All the drug resistant isolates were from re-treatment cases with a statistically significant association (P=0.005). Conclusion: The MODS technique is simple, and its implementation in this novel setting was feasible. MODS can be scaled up to meet the demand for MDR-TB confirmation in XpertMTB/Rif deployed sites in Nigeria.

Car windshield fragments as cheap alternative glass beads for homogenization of Mycobacterium tuberculosis cultures in a resource-limited setting.

Tuberculosis is a global health problem which has been compounded by the emergence and rapid spread of drug resistant strains. Phenotypic drug susceptibility testing of Mycobacterium tuberculosis usually requires homogenization of cultures using 3-5mm glass beads. In resource limited settings, these important material may either not be readily available in the country as in our case requiring that one orders them from abroad or they may be too expensive. In both situations, this would impact on the usually lean budget. In our centre were we recently introduced tuberculosis culture and drug susceptibility testing using the Microscopic Observation Drug Susceptibility (MODS) technique, we successfully used glass fragments from a broken car windshield obtained from a mechanic workshop to homogenize solid cultures to prepare positive controls. All cultures homogenized with these local beads gave consistent MODS results. The challenge of the limited availability of resources for research in resource limited settings can be met by adapting available materials to achieve results.