Antimicrobial susceptibility patterns of bacteria isolated from patients with ear discharge in Jimma Town, Southwest, Ethiopia

Antibiogram and molecular characterization of extended-spectrum β-lactamase-producing pathogens implicated in chronic suppurative otitis media

Introduction

beta-lactamase-producing bacteria, especially extended-spectrum beta-lactamase (ESBL) producers have strong clinical relevance and have been implicated in chronic suppurative otitis media (CSOM) treatment failures. This study aimed to determine the frequency, antibiogram, and molecular characteristics of ESBL-producing gram-negative bacterial (GNB) pathogens isolated from patients with CSOM.

Methods

three hundred (300) ear swab samples collected from patients with active CSOM were analysed using standard microbiological techniques. Antibiogram of pathogens was determined by Kirby-Bauer disk diffusion technique. Phenotypic detection and molecular characterization of ESBL-producing GNB pathogens were performed by double disk synergy test (DDST) and polymerase chain reaction (PCR).

Results

Escherichia coli and P. aeruginosa were more prevalent among CSOM patients with a duration of discharge >2 weeks. The frequency of ESBL producers among the GNB pathogens was 18.3%. Isolates were generally multidrug-resistant but very susceptible (100% - 70.4%) to ciprofloxacin, imipenem, and amikacin. Multiple antibiotic resistance values of the isolates ranged from 0.7-0.8. Polymerase chain reaction showed that blaSHV (47.6%) was the most predominant ESBL genotype. This was followed by blaTEM (25.2%) and blaCTX-M (10.7%) as the least predominant ESBL gene. Concomitant expression of ESBL gene was observed in 13.6% of the isolates.

Conclusion

this study reported the occurrence and spread of β-lactamase-producing bacteria in patients with CSOM infections. It is therefore very crucial to screen for antibiotic-resistant pathogens at early stages of CSOM infections, for proper antimicrobial therapy and to curb the increasing spread of antimicrobial resistance.

Factors Associated with Otitis Media Among Pediatrics in Two Government Hospitals in Arba Minch, Southern Ethiopia

Background

Bacterial otitis media (OM) is a common infection among the pediatric community worldwide and is the first reason for prescribing antibiotics in pediatric practices. However, if not promptly diagnosed and appropriately treated, it may persist and cause severe intra- and extra-cranial hard-to-cure complications. Hence, knowing the magnitude, etiology, and antibiotic susceptibility profile is very important for the proper management.

Methods

A cross-sectional study was carried out in 312 pediatrics (1 to 18 years) attending the Ear Nose Throat outpatient departments of the two title hospitals from 25 February to 30th August 2022. Patients were chosen through a systematic random sampling method. Data were obtained by means of a semi-structured questionnaire. Samples were collected to identify the causative bacteria as per microbiological guidelines. The antibiotic susceptibility test was done according to the Kirby-Bauer disc diffusion; SPSS version 25 was used for the analysis.

Results

The overall prevalence of otitis media was 67.3% (n=210); CSOM showed a slight preponderance (n=107) Gram-negative bacteria and Gram-positive bacteria were present in 59.8% (n=137) and 40.1% (n=92), respectively. Otitis media was predominantly caused by S. aureus (n=52, 56.5%), followed by Proteus spp. (n=33, 24%). Gram-negative bacteria were highly resistant to co-trimoxazole, amoxicillin-clavulanic acid, piperacillin, and tetracycline, whereas their positive counterparts were considerably penicillin and co-trimoxazole resistant. Overall, 61.5 and 19.2% of the isolates were MDR and XDR, respectively. MRSA, MR-CoNs, and VRE were 38.4% (n=20), 17.1% (n=5), and 58.3% (n=12), respectively; 19.7% (n=25) of Gram-negative bacteria produced ESBL, and 7% (n=9) were carbapenem-resistant. History of exposure to loud noise [AOR=3.4; CI=1.14-10.23; P-value=0.028] and family history of smoking at home [AOR=2.9; CI=1.18-7.25; P-value=0.020] have the greatest odds of otitis media.

Conclusion

Overall, the prevalence of otitis media is showing an upward trend, and MDR among bacterial isolates is increasing alarmingly.

Microbiological Assessment of Chronic Otitis Media: Aerobic Culture Isolates and Their Antimicrobial Susceptibility Patterns

As there are changing trends in the microbiology of chronic otitis media, this study was carried out to look for the current aerobic microbes and their antimicrobial susceptibilities in patients of chronic otitis media from north Indian region. A total of 322 patients who met the inclusion criteria were studied and aerobic ear swab culture was done under aseptic conditions. Gram staining was performed and antibiotic susceptibility testing was done using Kirby-Bauer disc diffusion method on Mueller-Hinton Agar. A total of 341 culture positive results were obtained from 322 patients. The culture results revealed 10 different aerobic microbes. Gram-positive floras were seen in 152 (44.57%), and Gram-negative in 189(55.43%) isolates. Staphylococcus aureus was the most common isolate present in 131 samples (38.41%), followed by pseudomonas aeruginosa in 101 (29.62%) and proteus in 36 (10.56%). In overall susceptibility of antibiotics against Gram-positive culture isolates, Vancomycin was most effective (97.37%). For Gram-negative microbes, Piperacillin-Tazobactum combination was most effective with overall susceptibility of 79.37% susceptibility. Microbiological assessment of Chronic Otitis Media should be carried out in an area on regular intervals because of the changing patterns of bacteriology and their antimicrobial susceptibilities.

Antimicrobial Resistance Through the Lens of One Health in Ethiopia: A Review of the Literature Among Humans, Animals, and the Environment

OBJECTIVES

We aimed to review and describe antimicrobial resistance (AMR) prevalence in humans, animals, and the environment in Ethiopia.

METHODS

We conducted a structured review of the literature on AMR in humans, animals, and the environment in Ethiopia from 2016 to 2020. We reported the pooled prevalence of AMR of bacterial pathogens in all three sectors.

RESULTS

We included 43 articles in our review. Only five studies evaluated AMR across multiple sectors. The most common bacteria in humans were Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. High prevalence of resistance to third-generation cephalosporins, fluoroquinolones, and sulfamethoxazole-trimethoprim were seen in gram-negative organisms, often with >50% prevalence of resistance. Highest resistance rates were seen in humans, followed by environmental isolates. Salmonella spp. exhibited higher rates of resistance than previously reported in the literature. We found methicillin-resistant S. aureus (MRSA) in approximately half of S. aureus from the environment and a third from human isolates. Few studies evaluated AMR across all three sectors.

CONCLUSION

Our review demonstrated high prevalence of AMR among bacteria in humans, animals, and the environment in Ethiopia. Integrating a One Health approach into AMR surveillance as part of Ethiopia's national surveillance program will inform future implementation of One Health interventions.

Bacterial Etiologies of Ear Infection and Their Antimicrobial Susceptibility Pattern at the University of Gondar Comprehensive Specialized Hospital, Gondar, Northwest Ethiopia: A Six-Year Retrospective Study

BACKGROUND

An ear infection is responsible for up to 40% of preventable hearing impairment; one of the reasons for frequent and unwise antibiotic usage, especially in the developing world. Since the incidence of antibiotic resistance is increasing, especially in resource-limited countries, up-to-date knowledge on the susceptibility of ear-discharge isolates to antibiotic is important for better patient treatment. Therefore, this study aimed at determining the bacterial etiologies and their antibiotic susceptibility profiles among patients suspected with ear infections.

METHODS

We collected retrospective data from bacteriological results of ear discharge samples from 2013 to 2018. Sample collection, culture preparation, and bacterial identification were performed using standard microbiological techniques. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standard Institute (CLSI) guidelines. We extracted and inputted the data using Epi-info version 7 and exported it to SPSS version 20 for analysis.

RESULTS

The overall ear-discharge culture positivity rate was 283/369 (76.7%) (95% CI = 72.4-81.3), with 14/283 (4.95%) mixed infections. Staphylococcus aureus (27.9%), Proteus spps (20.8%), Streptococcus spps (10%), and Pseudomonas spps (8.92%) were the main isolates. High-level resistance rates for tetracycline (77.6%), penicillins (67.2%), erythromycin (52.6%), and co-trimoxazole (52%), and low-level resistance rates for fluoroquinolones (23.3%), aminoglycosides (23.7%), and cephalosporins (29.8%) were observed. More than 45% of isolates, with 50.9% of Gram-negative and 37.3% of Gram-positive, were multidrug-resistant.

CONCLUSION

Staphylococcus aureus, Proteus mirabilis, Proteus vulgaris, Escherichia coli, and Pseudomonas aeruginosa were the leading cause of ear infections. The presence of high number of multidrug-resistant strains calls for the need for periodic and continuous follow-up of antibiotic usage in the study area. Further studies are recommended to explore the types of ear infections, with their etiologic agents and possible risk factors.

Major bacterial isolate and antibiotic resistance from routine clinical samples in Southern Ethiopia

Currently, antibiotic-resistant bacterial infections are a challenge for the health care system. Although physicians demand timely drug resistance data to guide empirical treatment, local data is rather scarce. Hence, this study performed a retrospective analysis of microbiological findings at the Hawassa public hospital. Secondary data were retrieved to assess the prevalence and level of drug resistance for the most common bacterial isolates from clinical samples processed at Hawassa University Comprehensive Specialized Hospital. Out of 1085 clinical samples processed in the microbiology laboratory, the prevalence of bacterial infection was 32.6%. Bacterial bloodstream infection was higher in children than in adults (OR, 4; 95% CI 1.8-14.6; p = 0.005). E. coli and K. pneumoniae were the commonest bacterial isolate both in children (36.8%, 26.3%) and in adults (33.3%, 26.7%) from the urine sample while, the leading bacteria identified from the CSF sample was P. aeruginosa, 37% in children and 43% in adult. In this study, all identified bacterial isolates were multi-drug resistant (MDR) ranging from 50 to 91%. The highest proportion of MDR was S. aureus 91.1 followed by K. pneumoniae 87.6%. Since the nationwide investigation of bacterial isolate, and drug resistance is rare in Ethiopia, a report from such type of local surveillance is highly useful to guide empirical therapy by providing awareness on the level resistance of isolates.

Extended spectrum beta lactamase producing bacteria among outpatients with ear infection at FelegeHiwot Referral Hospital, North West Ethiopia

BACKGROUND

Antibiotic resistant bacteria particularly extended-spectrum beta lactamase (ESBL) producing are of major concern for management of outpatients. They can spread rapidly and are associated with poor patient outcome. However, there is scarcity of information on ear infection with ESBL producing bacteria in Ethiopia. Therefore, this study investigates the prevalence of ear infection with ESBL producing bacteria among outpatients attending Felegehiwot Referral Hospital, Northwest Ethiopia.

METHODS

A hospital based cross-sectional study was conducted from May, 2018 to January, 2019. Demographic and clinical data were collected with face to face interview and were complemented with patient card review. Ear discharge specimens were collected from study participants using swab technique. All ear swab specimens were cultured using standard microbiological techniques. The ESBL producing bacteria were detected by double disc synergy test and interpreted based on Clinical and laboratory Standards Institute Guidelines. Chi-square and fisher's exact tests were calculated to check association between variables.

RESULTS

A total of 236 patients (male = 138 and female = 98) with ear infection took part in the study. The median age of the participants was 20years. Overall, 10 (4.23%, 95%CI; 2.3-7.6%) of patients had ear infection with ESBL producing bacteria. Other chronic illnesses (p = 0.003), history of hospital visit and treatment (p = 0.006) and history of antibiotic use without physician's prescription (p<0.001) had significant association with prevalence of ESBL producing bacteria in ear infection. The proportion of ear infection with ESBL producing P.mirabilis, P.aeruginosa and K.pneumoniae were 4 (1.7%), 3 (1.3%) and 2 (0.8%), respectively. All ESBL producing isolates were MDR (100%). Overall, 58 (43%) species were MDR. P.aeruginosa was the leading MDR isolate 29 (53.7%).For all bacterial isolates of ear infection, ampicillin(93.3%) and amoxicillin-clavulanic acid (58.5%) revealed high level of resistance whereas low resistance rates were observed for ciprofloxacin (5.2%), third generation cephalosporin (11.9-20%) and aztreonam (16.3%).

CONCLUSIONS

Ear infection due to ESBL producing bacteria coupled with high levels of MDR is becoming a growing concern for outpatients in the study area. Regular detection of these bacteria and wise use of antibiotics are needed to stop the spread of this form of resistance.

Pneumococcal serotype 19A is the major cause of pediatric acute otitis media with ruptured tympanic membrane in Addis Ababa, Ethiopia, 5 years after the introduction of the ten-valent pneumococcal conjugate vaccine

INTRODUCTION

In Ethiopia, there is a lack of data on pneumococcal serotypes causing acute otitis media (AOM) in children. We aimed to study the etiology, pneumococcal serotypes and antimicrobial resistance patterns of isolates from children with AOM with spontaneous perforation of the tympanic membrane (SPTM).

METHODS

We carried out a prospective observational study in children with AOM with SPTM, aged 0-15 years in Addis Ababa, Ethiopia. Middle ear fluid was collected using sterile swabs, cultured and antibiotic susceptibility testing was performed. Serotypes of Streptococcus pneumoniae were determined by sequencing the cpsB gene and by the Quellung reaction.

RESULTS

A total of 55 children were enrolled. Out of 55 samples that were cultured, 52 (94.5%) were culture positive for a total of 66 bacterial species, and 56.4% (31/55) samples were positive for 41 (62.1%) known pathogenic bacterial species. The most common pathogenic bacterial isolates were S. pneumoniae (36.6%), Staphylococcus aureus (19.5%), Streptococcus pyogenes (14.6%) and Haemophilus influenzae (12.2%). Serotype 19A (73.3%) was the predominant pneumococcal serotype. There was a high rate of non-susceptibility to penicillin (86.6%) and trimethoprim/sulfamethoxazole (80%) among pneumococcal isolates. Out of 21 different isolates tested for amoxicillin susceptibility, 15 (71.4%) were resistant.

CONCLUSIONS

Pneumococcal serotype 19A was the predominant cause of AOM with SPTM in children in Addis Ababa, Ethiopia, 5 years after introduction of PCV10. There was a high rate of resistance to commonly prescribed antibiotics. The study highlights the need for wide scale surveillance of the etiology and antimicrobial susceptibility of AOM in Ethiopian children.