Background
Streptococcus pneumoniae is one of the leading causes of bacterial meningitis and pneumonia in elderly people and children. Antimicrobial-resistant strains of Streptococcus pneumoniae have been detected in all parts of the world and have become one of the greatest challenges to global public health today. The aim of this study is, therefore, to assess the antimicrobial resistance profiles and multidrug resistance patterns of S. pneumoniae isolates from patients suspected of pneumococcal infections in Ethiopia.
Methods
A hospital-based prospective study was conducted from 2018 to 2019 at Addis Ababa and Amhara region referral hospitals. Antimicrobial resistance tests were performed on 57 isolates of S. pneumoniae that were collected from pediatric and adult patients. Samples (cerebrospinal fluid, blood, sputum, eye discharge, ear discharge, and pleural and peritoneal fluids) from all collection sites were initially cultured on 5% sheep blood agar plates and incubated overnight at 370C in a 5% CO2 atmosphere. S. pneumoniae was identified and confirmed by typical colony morphology, alpha-hemolysis, Gram staining, optochin susceptibility, and bile solubility test. Drug resistance testing was performed using the E-test method according to recommendations of the Clinical and Laboratory Standards Institute.
Results
Of the 57 isolates, 17.5% were fully resistant to penicillin. The corresponding value for both cefotaxime and ceftriaxone was 1.8%. Resistance rates to erythromycin, clindamycin, tetracycline, chloramphenicol and trimethoprim-sulfamethoxazole were 59.6%, 17.5%, 38.6%, 17.5% and 24.6%, respectively. Multidrug resistance (MDR) was seen in 33.3% isolates. The most common pattern was co-resistance to penicillin, erythromycin, clindamycin, and tetracycline.
Conclusions
Most bacterial isolates were susceptible to Ceftriaxone and Cefotaxime. Penicillin has been used as a drug of choice for treating S. pneumoniae infection. However, antimicrobial resistance including multidrug resistance was observed to several commonly used antibiotics including penicillin. Hence, it is important to periodically monitor the antibiotic resistance patterns to choose empirical treatments for better management of pneumococcal infection.