Antimicrobial Resistance of Neisseria gonorrhoeae Isolated from Out Patients Presenting with Urethral and Vaginal Discharges at Mbarara Regional Referral Hospital

Background: Gonococcus is one of the most common sexually transmitted diseases in developing countries and it has become a global health burden, hence a need for effective treatment. However, there is growing trend of antimicrobial resistant strains, in many parts of the world, to the previously effective antimicrobials thus creating serious health concerns.Setting: Mbarara Regional Referral Hospital -South-Western Uganda.Objectives:1) To determine the prevalence ofgonococcusamong out patients presenting with urethral and vaginal discharges at MRRH. 2) To determine the level of antimicrobial resistance ofgonococcusbased on phenotypic methods at MRRH.Design: The study was crosssectional and enrolled 189 participants presenting with urethral and vaginal discharges. The urethral and endo cervical swab samples collected were cultured on Chocolate media supplemented with 5%-10% carbondioxide in candle jar (inoculated plates were placed in a jar and a burning candle placed in the same jar, then closed, by the time the candle went off, that 5%-10% carbondioxide atmosphere would have been created). Isolates obtained were identified according to the laboratory standard operating procedures. Drug Sensitivity Test (DST) on confirmed Neisseria gonorrheaeisolates was performed using the Kirby Bauer technique. The colonies of the test organism were emulsified in peptone water and then inoculated on prepared sterile chocolate agarand the following discs were applied to it (Ceftriaxone discs (30μg), Erythromycin (15ug), Ciprofloxacin (10ug) and Penicillin (10IU). The plates were incubated at 37°C for 24-48 hours under 5% carbon dioxide atmospheres. The Zone of inhibition was seen around an antibiotic disc to which the organism was sensitive. Results: Out of the 189 participants whose urethral swabs and Endo cervical swabs were cultured, 89 were positive cultures (47%), out of which 25 (28%) were found to have gonococcal infection, 64 (72%) patients had other micro-organisms. The prevalence of NeisseriaGonorrhoeaewas 13%. In total, 4% of the isolates were resistant to Ceftriaxone, 28% to Ciprofloxacin, 68% to Erythromycin and 80% to Penicillin. A high percentage of resistance was observed against Penicillin (80%) and Erythromycin (68%).Conclusion: Adults aged 18 years and above who present at Mbarara Regional Referral Hospital with urethral or vaginal discharges are more likely to have a Neisseria gonorrhoeaewhich is resistant to Penicillin and Erythromycin

Clinical Description, Bacterial Causes and the Association of HIV with Pyodermas Presenting at a Skin Clinic of a Tertiary Hospital in Rural South Western Uganda.

Background: Diagnosis of pyoderma is clinical and antibiotic therapy in low resource setting is largely empirical. At MRRH Skin clinic repetitive visits by some patients with pyoderma led to speculation of antibiotic resistance. This indicated a need to survey the bacterial aetiology of pyoderma, their antibiotic susceptibility, clinical presentation, and look for association with HIV if any. Methods: We consecutively enrolled 216 study participants with clinical diagnosis of pyodermas in a descriptive cross sectional study. Consenting participants had photographic documentation of pyoderma lesions, HIV counselling and testing. Skin swabs were cultured and sensitivity performed on the isolates. Pearson’s chi-square and Fischer’s exact test were performed to determine association between HIV status and bacterial causes of pyoderma. Results: Non-bullous impetigo was the commonest clinical presentation, followed by folliculitis/perifolliculitis and lastly ecthyma. The major aetiological agents for the pyodermas were Staphylococcus aureus 77.78% and Streptococcus pyogenes 7.41% respectively. Other bacteria isolated were Klebsiella species 2.31% (5/216), Proteus species 1.85% (4/216) and Pseudomonas species 0.93% (2/216). Resistance of Staphylococcus aureus isolates to the anti-staphylococcal penicillin oxacillin was at 19.53% (33/169). The bacteria isolated from HIV positive participants were no different from that of HIV negative participants; for Staphylococcus aureus (82.35% versus 77.47% or p-value =0.527), Streptococcus pyogenes (5.88% versus 9.34% or p-value = 0.513) and for Klebsiella species (2.94% versus 2.75% or p-value = 0.647). Antibiotic susceptibility to most antibiotics was not significantly different between HIV positive and HIV negative participants except susceptibility to the cephalosporin cefalexin (p-value 0.039) which was much lower in the HIV positive pyoderma patients (83.87% versus 95.12%). Conclusion: Non-bullous impetigo is the most common pyoderma in this population with Staphylococcus aureus and Streptococcus pyogenes being the major causes of pyoderma and pyoderma aetiology was not affected by HIV status.

Prevalence and Genotypic Characterization of Extended- Spectrum Beta-Lactamases Produced by Gram Negative Bacilli at a Tertiary Care Hospital in Rural South Western Uganda.

Aim: To determine the prevalence and genotypic characterisation of extended spectrum beta-lactamases produced by gram negative bacilli isolated at Mbarara Regional Referral Hospital (MRRH). Samples: Gram negative clinical isolates. Study Design: Laboratory-based descriptive cross-sectional study. Place and Duration of the Study: MRRH, June and August 2012. Methods: Gram negative clinical isolates were sub cultured, and identified using biochemical tests. They were screened for ESBL by using oxyimino-cephalosporins and confirmed by double disc synergy Genotyping was performed using the PCR for TEM, SHV and CTX-M. Susceptibility pattern for the extended spectrum beta-lactamases, (ESBL) - positive isolates to other antibiotic classes was performed by the Kirby Bauer Technique. Results: A total of 484 isolates were included in the study. The commonest ESBL producers were Escherichia coli (34%), followed by unidentified coliforms (19.3%) and Klebsiella spp. (12.7%). Phenotypically, 88/484 were ESBL producers while genotypically 213/ 484 possessed ESBL genes. The ESBL genes were blaCTX-M (146; 70%), blaSHV (72; 34%) and blaTEM (100; 47%). 87of 213 isolates expressed more than one ESBL gene. Of these 36 (7.4%) produced blaCTX-M/blaSHV, 28 (5.8%) blaCTX-M /blaTEM, 4 (0.8%) blaSHV/ blaTEM and 19 (3.9%) blaCTX-M/blaSHV/blaTEM. Sixty two (16%) were phenotypically and genotypically positive, 12 (3%) of the isolates were phenotypically positive but genotypically negative and 140 (37%) isolates were phenotypically negative but genotypically positive. The ESBL producers were highly susceptible to imipenem (95%), nitrofurantoin (66%) but less susceptible to ampicillin (4%) and ticarcillin (7%). Conclusion: ESBL production among the Gram-negative clinical isolates at MRRH is very high with several isolates possessing multiple genes. The ESBL producers are highly susceptible to imipenem, but very resistant to ciprofloxacin.

Clindamycin Resistance among Staphylococcus Aureus Isolated at Mbarara Regional Referral Hospital, in South Western Uganda.

Aims: The study was conducted to determine the prevalence of Clindamycin (CL) resistance and antimicrobial susceptibility among clinical isolates of Staphylococcus aureus (S. aureus) from Mbarara Regional Referral Hospital (MRRH) in Southwestern Uganda. Study Design: Laboratory based cross sectional study. Place and Duration of the Study: The study was conducted at the Microbiology department of Mbarara Regional referral hospital between November 2012 and December 2013. Methodology: In our study, we recruited 300 S. aureus isolates that were stored in the laboratory and were obtained from different clinical samples. The isolates were tested for antimicrobial susceptibility by phenotypic methods and for the genotypic expression of Macrolide Lincosamide StreptograminB (MLSB) resistance genes (ermA, ermB, ermC, and msrA). The D-test was also performed. Results: Phenotypically, a total of 109 (36%) S. aureus isolates were resistant to CL, of which 9 (3%) were constitutively resistant while 100 (33.3%) were inducibly resistant. Genotypicaly, 134/300 (44.7%) isolates possessed at least one of the MLSB resistance genes. 23/300 (7.7%) tested positive for ermB, 98/300 (32.7%) tested positive for the ermC and 43/300 (14.3%) tested positive for the msrA genes with none possessing the ermA gene. Isolates were highly resistant to Sulfamethoxazole/trimethoprim, Erythromycin and Oxacillin with moderate resistance to Vancomycin and Imipenem and least resistance to Linezolid Conclusion: S. aureus resistance to CL was high in this set up. There was also high resistance to Sulfamethoxazole/trimethoprim, Erythromycin and Oxacillin but low resistance to Linezolid.

Prevalence and Antibiotic Susceptibility Patterns of Clinical Isolates of Methicillin- Resistant Staphylococcus aureus in a Tertiary Care Hospital in Western Uganda.

Aim: To determine the prevalence and antibiotic susceptibility patterns of clinical isolates of methicillin resistant Staphylococcus aureus isolated at Mbarara Regional Referral Hospital. Method: A total of 400 S. aureus isolates recovered from various clinical specimens at Mbarara Regional Referral Hospital were included in this study. Phenotypic screening was performed using Oxacillin. Presence of mecA gene was studied using polymerase chain reaction (PCR). The mecA positive isolates were tested for susceptibility to, Vancomycin, Imipenem, Fusidic acid, Trimethoprim/Sulfamethoxazole, Clindamycin and Linezolid using the Kirby Bauer technique. Results: Of the 300 isolates of S. aureus 31.3% (94) were phenotypically MRSA and 38% (114) had the mecA gene. All the MRSA isolates were susceptible to vancomycin and linezolid but were highly resistant to trimethoprim/sulfamethoxazole (70.2%). Of the 114 MRSA isolates 19.3% (22) were multi-drug resistant S. aureus (MDR-MRSA). The study found that there was a significant difference between genotypic and phenotypic detection methods (p < 0.001). Conclusion: The prevalence of MRSA in Mbarara is high (38%) with a high resistance to trimethoprim/sulfamethoxazole. The detection of mecA gene is a good predictor of methicillin resistance in S. aureus. There is a worrying prevalence of MDR MRSA among the clinical isolates of S. aureus in South Western Uganda.

Trends in Antimicrobial Resistance of Staphylococcus aureus Isolated from Clinical Samples at Mbarara Regional Referral Hospital in Rural Uganda.

Aim: This study aimed at describing the antibiotic susceptibility patterns of S. aureus isolated from clinical samples at Mbarara Regional Referral Hospital from 2003 to 2012. Methods: This was a retrospective study that included clinical specimens cultured at the Microbiology laboratory of Mbarara Regional referral hospital between 2003 and 2012. Cultures and sensitivity data were abstracted from the laboratory registers using a data abstraction form. Among the positive culture reports, the antibiotic sensitivity of the common bacteria isolated were also recorded. Analysis of susceptibility data was limited to Staphylococcus aureus, the commonest organism identified. The data were entered into Epi info and exported to Stata Version 12.1 for analysis. Results: A total of 36,080 cultures were performed over a period of 10 years. Of these 7,744 (21.5%) specimens grew an organism. S. aureus was the most prevalent organism isolated. Fifty nine percent of the S. aureus was isolated from blood samples followed by 22% from pus samples, urine (8%) and HVS (5%). During the study period, resistance of S.aureus to chloramphenicol, amoxycillin, penicillin, tetracycline, and cotrimoxazole ranged from 50-90% while S. aureus resistance to Gentamicin and ceftriaxone ranged from 10-20%. Conclusion: Over the last decade, S. aureus isolates showed up to 90% resistance to commonly prescribed oral antibiotics. We recommend regular review of antibiotic resistance patterns to inform hospitals’ on guidelines on empirical antibiotic prescription, especially in resource-limited settings where susceptibility testing may not be feasible.