Medical Microbiology

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Browsing Medical Microbiology by Author "Abebe Tamrat"

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    A Comparison of Arginase Activity in the Saliva Plasma and Peripheral Blood Mononuclear Cells(PBMC)of Pulmonary Tuberculosis Patients in Addis Ababa, Ethiopia
    (Addis Ababa University, 2011-05) Yassachew Yayehyirad; Abebe Tamrat ; Mihret Adane ; Kropf Pascale
    Background: Mycobacterium tuberculosis (MTB)is the causative organism of the chronic bacterial infection, tuberculosis (TB). TB is one of the leading causes of death due to infectious diseases worldwide. Recently it has been observed that arginase (ARG)-is no longer a mere enzyme responsible only for urea cycle but is a key enzyme that plays a great role in modulation of the immune response and thus, pathogenesis. Infection with MTB and other intracellular pathogens induces the activation of ARG and inducible nitric oxide synthase (iNOS) which competitively metabolize L-arginine as a common substrate to produce L-ornithine and nitric oxide (NO), respectively. ARG induced deprivation of Larginine is important for pathogens to limit the intracellular production and killing action of NO and T cell responses. Therefore, induction of ARG might be an important escape mechanism for the survival of MTB. Materials and Methods: A cross-sectional study was carried out to compare the level of ARG activity in the saliva, plasma and peripheral blood mononuclear cells (PBMCs)of newly diagnosed HIV sero -negative smear positive TB patients (n=18) and healthy controls (n=8). The level of arginase activity in all type of samples was measured by enzymatic assay and a two-tailed Mann-Whitney U test was performed to assess statistical differences. Results: There was a statistically significantly higher level of arginase activity in the PBMCs (p=0.015)and saliva (p=0.008)of TB patients than those of healthy controls. Furthermore, an increased level of arginase activity was detected in the plasma of TB patients as compared to healthy controls, however it was not statistically significant (p=0.211). A significantly higher (p=0.024)frequency of arginase expressing cells were detected in the PBMCs of TB patients as compared to healthy controls. The phenotype of these cells was identified as CD15 + neutrophile. Conclusions and recommendation: Infection with MTB can result in an increased frequency of ARG-expressing cells as well as in increased level of arginase activity in the PBMCs, saliva and plasma of the TB patients. Therefore, the measurement of ARG activity in saliva might be used as a biomarker of TB infection.
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    Detection of Potential Pathogenic and Drug Resistant Bacteria Isolated from Inanimate Hospital Environments in Operation Theaters and Intensive Care Units of Tikur Anbessa Specialized Hospital and ALERT Hospital in Addis Ababa, Ethiopia
    (Addis Ababa University, 2020-02) Sebre Shemse; Abebe Tamrat; Mihret Adane
    Background: The role of hospital environments especially those of the operation theaters (OTs) and intensive care units (ICUs) in the transmission of hospital associated pathogens and multidrug resistant (MDR) bacterial strains like Extended-Spectrum β-Lactamases (ESBLs), Methicillin-resistant S. aureus (MRSA) and Vancomycin resistant Enterococci (VRE) dissemination are critical and an essential element in the control of Health care associated infections(HAIs) and emergence of resistance genes. Objectives: The current study aimed to detect potential pathogenic and drug resistant bacteria from inanimate hospital environments in OTs and ICUs of the selected hospitals. Methodology: A cross-sectional study was conducted on 280 hospital environmental samples in two different hospitals from June to September, 2018 G.C: Tikur Anbessa Specialized Hospital (TASH) (n=187) and All Africa Leprosy Rehabilitation and Training Hospital (ALERT) (n=93). Settle plate’s method (Passive air sampling following 1/1/1 schedule) was used for air sample collection while swab method was used to collect samples from inanimate surfaces in the OTs and ICUs of the selected hospitals. A total of 257 environmental swabs and 23 air samples were collected from different sites of ICUs and OTs. All isolates/samples were identified by using routine bacterial culture, Gram staining and a panel of biochemical tests. For each identified bacteria antibiogram profiles were determined by the Kirby Bauerdisk diffusion method based on the Clinical and Laboratory Standards Institute (CLSI) guidelines. Double disk synergy test was used to confirm ESBL production while Modified Hodge test (MHT) was used to screen carba pen emases production. On the other hand, Cefoxitin /oxacillin discs were used to screen MRSA. Results: Out of 280 swabs and settle plates, 227(81%) of samples were positive for bacterial contamination. A total of 282 bacteria were identified. Of these, the predominant bacteria identified from the environmental samples from OTs and ICUs were S. aureus (27.5% vs 9.6%), Coagulase negative Staphylococcus (CONS) (16% vs 2.8%) and Acinetobacter spp(2.5% vs 14.5%) respectively. The bacterial load on air was found beyond the standard limits. The most common bacterial contaminated sites were bed linens 37(13.1%), followed by environmental surfaces including (wall, floor, corridor and door knob) 35(12.4%) and beds 33(11.7%). Out of the280environmental samples 76(27.1%), 25(8.9%) and 7(2.5%) were MRSA, ESBL and Carbapenemase producer bacteria respectively. Most the identified bacteria showed considerable resistance to antibacterial agents. Of the total 282 identified bacteria, 158(56%) of the isolates were resistant to at least 3 antibiotics and 58 multi-drug resistance phenotypes were exhibited by the MDR isolates. Conclusion: Hospital environment especially those of the operation theaters and intensive care units are highly contaminated with potential pathogenic bacteria. Bacterial isolates were highly resistant to commonly used antibiotics with high multi-drug resistance percentage. Therefore, well-designed infection prevention and control strategies should be in place for combating health care-associated infections and the consequences.
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    Epidemiology and Molecular Characterization of Mycobacterium Bovis in Humans and Cattle and Assessment of its Zoonotic Importance in Central Ethiopia
    (Addis Ababa University, 2021-11) Gizat Almaw; Mihret Adane ; Abebe Tamrat
    Mycobacterium bovis (M. bovis) is a member of the Mycobacterium tuberculosis complex (MTBC) and causes tuberculosis in humans (zoonotic tuberculosis-zTB) and animals, mainly in cattle (bovine tuberculosis-bTB). There were limited studies on zTB in Ethiopia but also a reliable estimate of bTB prevalence in cattle in central Ethiopia is missing. In addition no wholegenome sequencing (WGS) based M .bovis studies had been performed in Ethiopia before this study. Also, there has been a limited effort in search for an alternative diagnostic method to culture to detect M. bovis in clinical specimens. Therefore, due to these research gaps, this study, which combined bTB and zTB, was conducted from 2018 to 2021 in central Ethiopia (Addis Ababa, Sebeta, Holeta, Sululta, Sendafa and Bishoftu) with the objective of generating epidemiological and molecular data to update our understanding on bTB/zTB. The bTB study in cattle involved a cross sectional one-stage cluster sampling survey of dairy farms in central Ethiopia using tuberculin skin testing and the collection of additional data by questionnaire to estimate the prevalence of bTB and identify potential risk factors contributing to Btb transmission. For the zTB part, surveillance of TB in humans was carried out among individuals working in bTB infected dairy farms, patients presented at selected health centers, and exposure to risk factors was assessed using questionnaire. From consenting TB suspected individuals, demographic and clinical information was collected by questionnaire. Sputum and Fine Needle Aspirates (FNA) samples were collected from suspected cases. In addition, isolation of M. bovis was done from raw milk collected from tuberculin skin test positive cows and from cattle tissue lesions. The genetic diversity of M. bovis isolates was examined using spoligotyping and whole genome sequencing (WGS) analysis. Furthermore, in this study the performance of a TaqMan real time PCR (RT-PCR) assay as an alternative diagnostic method to culture was evaluated. Two hundred ninety-nine (n=299) dairy herds in the six study areas were randomly selected, from which 5,675 cattle were tested. The overall prevalence of bTB after standardisation for herd-size in the population was 54.4% (95% CI 48.7-60%) at the herd level, and it was 24.5% (95% CI 23.3-25.8) at the individual animal level. A Generalized Linear Mixed Model (GLMM) was used to explore risk factors association with bTB status. We found that herd size, animal age, bTB history at farm, and breed were significant risk factors. With regard to zTB, among 110 DFWs in 73 bTB infected dairy farms, 41 had at least one of the symptoms that are typical forTB. Three DFWs had swollen nodes at their neck, a symptom typical for TB lymphadenitis. In assessment of risk factors: raw milk consumption was practiced by more than two thirds of theDFWs with symptoms of TB (68.2%) and over half of DFWs with symptoms did not think TBcould be transmitted via raw milk consumption. Overall in the surveillance of zTB (active and passive), a total of 167 specimens (sputum=131; FNA=36) were collected from 161 TB suspected individuals for the isolation of M. bovis. Of these processed specimens, three samples with M. bovis were detected in total (1.8%, n=167). And of these three, one M. bovis isolate was sequenced and the genotype was spoligotype SB1476 which was previously reported from cattlein Ethiopia suggesting possible zoonotic transmission. With regard to isolation and characterization of M. bovis from cattle, out of 827 cattle (abattoirs and dairy farms), 76 of them(9.2%) had tuberculous lesion. From these tuberculous lesions, 62 isolates (n=137 samples) from42 animals were confirmed to be M. bovis. Similarly out of 975 milking cows which were tuberculin skin test positive (37.8%, n=2582), 490 composite raw milk samples were collectedand of these 11 (2.2%) yield M. bovis isolates showing evidence that raw milk is not safe and can be a source of infection for human TB due to M. bovis. The genetic diversity of 74 M. bovisisolates (one being a human isolate) was assessed and ten different spoligotypes were recorded. In cattle spoligotype SB1176 was the most prevalent type (n=31, 44.3%) followed by SB0133(n=11, 15.7%). Our WGS analysis with a total of 55 M. bovis isolates sequenced (one being ahuman isolate) showed three clonal complexes clearly segregating in the phylogeny: African 2(Af2; n=47), European 3 (Eu3; n=7) and Unknown8 (n=1). In addition, the present study reported for the first time clonal complex European 3 (Eu3) from Ethiopia. With regard toTaqMan assay performance evaluation - the assay performance on 440 clinical samples was variable for different specimens and overall performed well for sputum samples for all targets. In conclusion, this study recorded high prevalence of bTB in dairy cattle in central Ethiopia. M.bovis prevalence in humans in central Ethiopia was low; however, further investigation is neededin all regions at national level given bTB is endemic in cattle in Ethiopia. Knowledge gap onbTB and M. bovis isolation from milk, showed that there is a clear potential for zoonotic transmission and needs further investigation. The TaqMan RT-PCR assay is a promising methodology for the diagnosis of zTB and bTB, but with further validation works needed usingdifferent targets and specimens
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    Genotype Distribution of Human Papillomaviruses & HPV E6/E7 RNA Test for the Detection of High-Grade Cervical Intraepithelial Neoplasia (CIN2+) Among Gynecology Complaints in Northwest Ethiopia
    (Addis Ababa University, 2023-07) Derbie Awoke; Abebe Tamrat ; Woldeamanuel Yimtubezinash
    Background: In developing nations, cervical cancer (CC) is the main cause of cancer-related fatalities in women due to the absence of well-established vaccination and screening programs. Exploring the best triage test for women with cervical abnormalities is a timely area of research to advance cervical screening and management. Further, the distinct proportional impact of each HR-HPV on the distribution of cervical lesions varies geographically. There is a shortage of data regarding the clinical value of high-risk human papillomaviruses (HR-HPV) E6/E7 mRNA test and their molecular epidemiology in cervical samples from Ethiopia, particularly in the current study area. Moreover, despite the fact that HR-HPV infection is an essential biological cause of CC, other socio-demographic factors are not well studied in the nation. Therefore, this study aimed to fill these data gaps. Objectives: The aim of the study was to determine the HPV genotype involved in cervical lesions, to evaluate the clinical use of HR-HPV E6/E7 mRNA for the early detection of CIN2+, and to explore factors associated with it among gynecology complaints in northwest Ethiopia. Methods: Between March 2019 and October 2021, a cross-sectional study was carried out at Felege Hiwot Compressive Specialized Hospital (FHCSH). Among women who visited the hospital for gynecological examination, those who were eligible for visual inspection (VIA) based screening were included. Cervical punch samples were obtained by a gynecologist for histological analysis. Cervical swabs collected and analyzed for HR-HPV DNA and HPV E6/E7 mRNA using the Abbott Alinity m system and real-time PCR, respectively at the Institute of Virology, Leipzig University, Germany. Demographic and gynecologic-related history were collected using a structured questionnaire. The distribution and frequency of HR HPVs described using descriptive statistics. Histology was used as the reference test to determine how well the E6/E7 mRNA detected CIN2+. Results: Of the 355 study participants (aged 30 to 80 years), more than half, 211 (59.4%), were unaware of CC, and their previous cervical screening practice was approximately 25%. Cervical biopsies from 41.8% (140/335; 95% CI: 36.6-47.1%) participants were diagnosed as cancer. The proportion of HR-HPV was 53%(188/355; 95%CI: 47.8-58.1%), with 13 different genotypes identified. HPV16 was predominant at 50.4% (95%CI: 29.4-39.2%), followed by HPV31 (9.7%), HPV33 (8.5%), HPV39 and HPV68 (5.8% each), and HPV18 at 4.7%. The iii E6/E7 mRNA test was positive in 35.8% (127/355; 95%CI: 30.0-40.9) of cases for HPV16, 16 & 45. The proportion of positive HPV DNA test results for these three HR-HPVS was 42% (149/355). The total agreement of DNA and mRNA tests in the detection of these HPVs was at 92.7% (95%CI: 89.5-94.9) with a kappa value of 0.821. HPV16, at 108 (85%), was the most common genotype expressing E6/E7 mRNA. The mRNA assay had sensitivity, specificity, positive and negative predictive values (PPV and NPV) of 65.2% (95%CI: 57.5-72.2%), 90% (95%CI: 84.6-93.4%), 85.8% (95%CI: 78.5-91.0%), & 73.6% (95%CI: 67.2-79.1%), respectively for detecting histologically confirmed CIN2+. Specifically, the sensitivity and specificity of this assay in the detection of CIN2+ were 92.7% & 47%, respectively among HPV16, 18, & 45 DNA-positive cases. Likewise, the analytical sensitivity and specificity of the HPV-DNA test were 84.8% & 74.1%, respectively. CC increased steadily with participant age, with women older than 50 years about four times more likely to develop CIN2+ (AOR: 3.68 95%CI: 1.75-7.72, p < 0.001). Similarly, no cervical screening in the past five years (AOR: 2.04; 95%CI: 1.04-4004; p = 0.038), infection with HR-HPVs (AOR: 5.28; 95%CI: 2.66-10.47; p < 0.001) and tested positive for E6/E7 mRNA (AOR: 5.78; 95%CI: 2.73-12.24, p < 0.001) were statistically associated with CIN2+. Conclusions: CC is still a significant issue for women's health in northwest Ethiopia that requires evidence-based interventions. The E6/E7 mRNA test and the HPV DNA test demonstrated good agreement and showed better diagnostic relevance in detecting CIN2+. Therefore, the test can be considered for colposcopy and biopsy triage. In particular, the mRNA test may be regarded as a potential triage for women who are HPV-positive , mainly in regions with a shortage of pathologists and colposcopy facilities. Vaccination and future HPV-based screening methods in Ethiopia should consider the important HR-HPV genotypes identified in such studies. To better assess the HPVs circulating in northwestern Ethiopia, community-based surveys should be conducted. Likewise, to optimize the E6/E7 mRNA analytical sensitivity and specificity , large-scale studies targeting major HR-HPVs should be considered. Finally, in accordance with the WHO recommendation women who are eligible for cervical screening need to be screened with a high-precision test, including HPV-based tests. Keywords: Cervical cancer, CIN2+, HPV E6/E7 mRNA, HR-HPV DNA, northwest Ethiopia
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    Human Papillomavirus in Women with Pre-Cancerous Lesion and Cervical Cancer: the Use of Urine as an Alternative Specimen
    (Addis Ababa University, 2021-05) Firdawoke Ededia; Abebe Tamrat; Teka Brhanu
    Background: In a country where the coverage cervical cancer screening is low optimization of the uptake is critical. The implementation of high precision test is advocated by WHO. To augment the implementation human papillomavirus (HPV) based screening in Ethiopia we compared the performance urine HPV DNA test with cervical swab. Methods: Paired samples (n=103) of first void urine and cervical swab were collected from patients Gynecology Clinic of Tikur Anbessa Specialized Hospital (TASH). After extraction of DNA using QIAamp® DNA Mini Kit (Qiagen) the HPV infection, coinfection and type-specific HPV distribution was determined using the Anyplex HPV28 DNA genotyping kit (Seegene, Seoul, Korea) and CFX96 IVD (In Vitro Diagnostic) Real-Time PCR System. The kit simultaneously detects, differentiate, and semi-quantify 28 HPV genotypes 19 high risk (Hr)-HPV types; HPVs 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 69, 73 and 82 and 9 LR-HPV types; HPVs 6, 11, 40 ,42, 43, 44, 54, 61 and 70. Additionally, blood sample was collected to detect HPV16 L1 anti-capsid antibody using Prevo-check ® (Abvirus Germany GmbH). It is immunologic rapid test that directs against a protein that is produced by HPV 16 infected cells which interferes with cell division. Pap smear was done by a pathologist and histology results was collected from the chart of the patients and a clinical form was used to collect basic information from the patients by the attending midwife nurses. Result: Of the 103 paired samples, HPV infection prevalence was 83.5% in cervical and 77.7% in urine samples. HPV 16 is the most prevalent in both samples with 56.8% in cervical swab and 54.6% in urine sample followed by HPV 18 (5.8%) in cervical swab and HPV 18 and HPV 39 (6.2%) in urine samples. Multiple infection rate (infection more than one type of HPV) was 22.4% in urine samples and 32.0% in cervical swab. The agreement in the detection of HR-HPV between urine and cervical samples was moderate with a kappa value of 0.57 at 95% CI. Using the cervical HPV results as a reference, the anaylitical sensitivity of urine HPV testing was 88.4% (76/86) and specificity of 76.5% (13/17) and ROC area of 0.82 with (0.7-0.9) 95% CI. The Prevo-check HPV16 L1 antibody test has detected antibody from seven patients have a low clinical sensitivity but specificity of 100%. Of 93 histology result; 69.9% of the participants were diagnosed with SCC. HR-HPV detected in 76.2% and 79.7% from cervical and urine samples. Conclusion: In a country with low cervical cancer screening uptake collection of urine specimen can be considered as an alternative sample since the sample is easy to obtain, showed good diagnostic performance and may increases uptake of cervical cancer screening in Ethiopia. HPV16 and 18 were the predominant HPV detected from women with CIN2+ and above patients.
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    Isolation and Antibacterial Suseptibility Pattern of STREPTOCOCCUS AGALACTIAE in Pregnant women in Adigrat Zonal Hospital and Adigrat Health Center, Tigray,Ethiopia.
    (Addis Ababa University, 2012-06) Kahsay Tsega; Abebe Tamrat; Mihret Adane
    Back ground: S. agalactiae which are group B Streptococci asymptomatically colonize the vaginal or rectal areas of 10 to 30 % of pregnant women. In these women, S. agalactiae may cause preterm labor or membrane rupture, as well as urinary tract infections, chorioamnionitis, postpartum endometritis, postpartum wound infection, septic pelvic thrombophlebitis, endocarditis and sepsis. These bacteria is a major cause of invasive disease at all ages and is the most frequent cause of serious bacterial sepsis, including neonatal meningitis. Objective: This study was undertaken to determine the carriage rate of S. agalactiae and to assess theiantimicrobial susceptibility pattern. An attempt has been also made to identify the possible risk factors related with S. agalactiae colonization. Methods: Rectal and vaginal swabs were obtained from 150 pregnant women at 35-37 weeks of gestational period that attended anti natal clinic at Adigrat Zonal Hospital and Adigrat Health Center. The specimen was cultured on selective CHROMagar StrepB and incubated aerobically at 37o c for 18-24 hours. Suspected colony of S. agalactiae mauve colony (pink color) was confirmed by gram stain, catalase test, Christie, Atkins, MunchPeterson (CAMP) testing and latex agglutination (serological) test. In cases of positive cultures obtained, antibiotic susceptibility tests were carried out on all S. agalactiae isolates using the disc diffusion technique on Mueller-Hinton agar supplemented with 5% sheep blood and incubated at 37 0 c for 20-24 hours in 5% co. A univariate and multivariate binary logistic regression model was used to ascertain the association between the frequencies of colonization in relation to the different variables. Results: Seventeen of the study participants (11.3%) were colonized by S. agalactiae. Thirteen (76.5%) of the isolates were from health center and 4(23.5%) werfrom hospital. The study revealed a higher colonization rate among the age group 21 to 30 years (76.5%) but one pregnant woman with S. agalactiae was identified (5.9%) in women aged lesser than or equal to 20 years. Bacterial resistance was not detected against ampicillin, penicillin G, amoxacilline and vancomycin, whereas 11.8% and 17.6% of the isolates were resistant to TMerythromycin and clindamycin respectively. Intermediate susceptibility was also detected in 2 isolates (11.8%) against erythromycin and in 2 isolates (11.8%) against clindamycin. By multi variant logistic regression analysis, Prolonged rupture of membrane was associated with a higher colonization rate of S. agalactiae (OR=5.864, 95% CI= 1.395 – 24.643, Pvalue=0.016). No significant association was identified between S. agalactiae colonization rates with other socio- demographic/gynecological characteristic of the pregnant women. Conclusion: The carriage rate of S. agalactiae in the study area was 11.3%. High S.agalactiae isolates weredetected from Adigrat Health Center. Prolonged rupture of membrane was strongly associated with the colonization of S. agalactiae. Based on the finding, penicillin G was the best antibiotic for the treatment of S. agalactiae. Out of the isolates 11.8% were resistance to erythromycin and 17.6% were resistance to clindamycin Common resistance to erythromycin and clindamycin was seen in two isolates.
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    Phenotypic Antimicrobial Resistance Profiles of Klebsiella Pneumoniae Isolated from Patients at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia
    (Addis Ababa University, 2019-10) Awoke Tewachew; Abebe Tamrat ; Mihret Adane; Aseffa Abraham ; Teka Brhanu ; Yeshitela Biruk
    Background: Klebsiella pneumoniae is a cause of mild to life threatening infections. The bacterium poses an urgent public health threat because it has the potential to become resistant to virtually all categories of antimicrobials available. Multidrug resistant K. pneumoniae has caused nosocomial outbreaks in different continents. Little is known concerning the antimicrobial resistance profiles of K. pneumoniae in Ethiopia. Objective: The aim of this study was to determine the phenotypic anti microbial resistance profiles of K. pneumoniae isolated from patients at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia. Methodology: A cross-sectional study was conducted on antimicrobial resistance profiles of 132 K. pneumoniae, isolated from patients from September 2018 to February 2019. Identification of K. pneumoniae was done by examining gram stain, colony characterstics on MacConkey agar, 5% sheep blood agar and biochemical tests. Antimicrobial susceptibility testing was done by Kirby-Bauer disc diffusion technique. Extended spectrum -lactamase (ESBL) and carbapenemase production was confirmed by combined disc test and modified carbapenemase inactivation method, respectively. Data was double entered using Epidata 3.1 and exported to SPSS version 25 software for analysis. Binary logistic regression and Chi-Square or Fisher's exact test were used to measure the association. P-value less than 0.05 was considered as statistically significant. Results: Among the total K. pneumoniae isolates high frequency of resistance was observed to cefotaxime and ceftriaxone 128 (97%), trimethoprim sulfamethoxazole 124 (93.9%) and cefepime 111 (84.1%). Most frequent susceptibility was observed to amikacin 123 (93.2%), imipenem 107 (81.1%), meropenem 96 (72.7%) and ertapenem 93 (70.5%). Majority 130(98.5%) of the isolates were multidrug resistant (MDR). Two isolates showed complete nonsusceptibility to all antimicrobial agents tested. The magnitude of ESBL and carbapenemase production was 77.3% and 21.2%, respectively. Of the total (n=30) non-ESBL producers, 73.3% were carbapenemase producers. Non-ESBL producers showed high resistance to imipenem (53.3%), meropenem (80%) and ertapenem (83.3%). Higher proportion of ESBL production was observed in those aged below 5 years than those 18 to 45 years and among those admitted to the intensive care units and pediatric wards than those in medical wards. Previous use of carbapenems was associated with carbapenemase production (P<0.001). Conclusion: All K. pneumoniae isolates showed appreciably high frequency of resistance to most of the tested antimicrobials. The magnitude of ESBL and carbapenemase production as well as MDR K. pneumoniae was very alarming in the study area. Of particular concern is that the majority of non-ESBL producers were carbapenemase producers. Therefore, strengthening antimicrobial stewardship programs together with effective infection control and antimicrobial surveillance practices is strongly recommended in Tikur Anbessa Specialized Hospital.