Discordance between genotypic and phenotypic methods for the detection of rifampicin and isoniazid resistant Mycobacterium tuberculosis and the correlation with patient treatment outcomes.

Background: Accurate drug susceptibility testing (DST) of Mycobacterium tuberculosis (MTB) is essential for proper patient management. We investigated discordance between genotypic (Xpert MTB/RIF and MTBDRplus) and phenotypic (MGIT 960) methods for the detection of rifampicin (RIF) and isoniazid (INH) resistant MTB and its correlation with patient treatment outcomes in Jimma, Southwest Oromia, Ethiopia. Methods: A retrospective study was conducted on 57 stored MTB isolates with known Xpert RIF resistance status (45 RIF resistant and 12 RIF susceptible) at Jimma University Mycobacteriology Research Center from November 2, 2021, to December 28, 2022. We did MTBDRplus and phenotypic DST (using the Mycobacterial Growth Indicator Tube (MGIT) system). The Xpert and MTBDRplus results were compared using phenotypic DST as a reference standard method. The treatment outcome was determined as per national guideline. The discordance between the genotypic and phenotypic DST was calculated using GraphPad software. Results: Among the 57 MTB isolates, six (10.5 %) had discordant results between the two DST methods. Xpert yielded five discordant results for RIF when compared with phenotypic DST (kappa coefficient (κ) = 0.76, 95 % confidence interval 0.56-0.96). The MTBDRplus compared with phenotypic DST gave three discordant results for RIF (κ = 0.86, 95 % confidence interval 0.71-1.00) and three for INH (κ = 0.86, 95 % confidence interval 0.70-1.00). Compared with Xpert, MTBDRplus yielded lower discordance with phenotypic DST for RIF. Out of six patients with discordant results, three had unfavorable outcomes while the other three were cured. Of the three patients with unfavorable outcomes, only one patient has received an inappropriate treatment regimen. There was no correlation between unfavorable outcomes and incorrect treatment regimens due to discordant results (Χ2 = 0.404; P = 0.525). Conclusions: Discordance between genotypic and phenotypic DST for RIF or INH occurred in 10.5 % of isolates. Only one patient with discordant results has received an inappropriate treatment regimen, resulting in an unfavorable outcome. The impact of parallel use of rapid molecular assay with phenotypic DST on patient treatment outcomes requires further study.

Resistance to pyrazinamide in Mycobacterium tuberculosis complex isolates from previously treated tuberculosis cases in Southwestern Oromia, Ethiopia.

Objective: Pyrazinamide (PZA) susceptibility testing is important to develop evidence-based algorithms for case management. We aimed to assess the prevalence of PZA-resistance and its impact on treatment outcomes in previously treated tuberculosis (TB) cases in southwestern Oromia, Ethiopia. Methods: A Phenotypic Drug Susceptibility Testing (DST) of PZA with BACTEC MGIT 960 was conducted at the Mycobacteriology Research Center of Jimma University (MRC-JU) from June to November 2021 on sixty-six Mycobacterium tuberculosis complex (MTBC) isolates from previously treated TB cases. SPSS software package version 21 was used. The differences in the proportion of PZA resistance between the groups were compared using the chi squared test. Logistic regression was used to identify the association between PZA resistance and treatment outcomes. Results: Among 66 MTBC isolates (49 rifampicin-resistant and 17 rifampicin-sensitive) included in this study, 31.8 % were resistant to PZA. The proportion of PZA resistance was almost three times higher in previously treated TB cases with rifampicin resistance than in rifampicin-sensitive patients (38.8 % vs. 11.8 %, p = 0.039). An unfavorable treatment outcome was documented for 23 % (15/65) of the participants. Patients with PZA resistance were almost four times more likely to have an unfavorable treatment outcome than patients with PZA sensitive (aOR 4.2, 95 % CI: 1.13-15.3). Conclusions: The prevalence of PZA resistance was high compared to the pooled PZA resistance estimated worldwide. The majority of TB cases with PZA resistance had an unfavorable treatment outcome. PZA susceptibility testing should be included in the multidrug-resistant TB diagnostic algorithm to improve management of these patients.

Diagnostic implications and inpatient mortality related to tuberculosis at Jimma Medical Center, southwest Ethiopia.

BACKGROUND: Tuberculosis (TB) is one of the major public health problems in Ethiopia. Determining discharge outcome of TB cases helps to understand the effectiveness of TB diagnosis effort to improve case management. The objective of this study was to assess discharge outcomes and factors associated with death among patients on TB treatment admitted in a referral hospital in southwest Ethiopia. METHODS: A retrospective study was conducted in Jimma Medical Center by reviewing medical records of TB patients (age ≥15 years) admitted to medical wards from January 2015 to December 2017. Demographic and related data was collected using data collection format. The clinical evaluation outcome of an individual patient at discharge was recorded. Descriptive statistics were used to summarize participant characteristics. Multivariate logistic regression analyses were used to evaluate the risk factors for TB mortality. RESULTS: Among 465 patients included in the review, 225 (48.4%) were pulmonary (PTB) and 240 (51.6%) extra-pulmonary TB (EPTB) cases. Overall, 190 (40.9%) had bacteriologically confirmed for TB. HIV status was documented for 340 (73.1%) of them; 93 (27.4%) were found to be positive. The prevalence of HIV infection among EPTB and PTB cases was 50/275 (18.2%) and 43/190 (22.8%), respectively. A quarter of the patient, 114 (24.5%), died in the hospital while the rest were discharged with clinical improvement. Compared to smear positive PTB, the risk of death was two times higher in patients with smear negative PTB cases (aOR 2.3, 95% CI: 1.3-4.2). TB patients with coronary obstructive pulmonary disease (COPD) (aOR 4.6, 95% CI: 1.3-16.7), diabetes mellitus (aOR 5.7, 95% CI: 1.5-23.7), heart disease (aOR 3.8, 95% CI: 1.4-10.4) had about four-fold increased risk of death. HIV-positive patients had a higher risk of mortality (aOR 2.9, 95% CI: 1.7-5.0) than HIV-negative patients. The risk of death was not affected by the type of TB diagnosed, as 27.6% of EPTB and 31.9% PTB were died (p = 0.457). CONCLUSION: TB was associated with high inpatient mortality at Jimma Medical Center. Mortality was found to be higher among unconfirmed cases, those with COPD, diabetes mellitus, heart disease and HIV infection. Thus, any effort to curtail mortality in such high TB burden setting should focus on improving TB diagnosis and addressing major comorbid medical conditions.

Factors associated with unsuccessful treatment outcome in tuberculosis patients among refugees and their surrounding communities in Gambella Regional State, Ethiopia.

BACKGROUND: Tuberculosis (TB) is a leading cause of public health challenges among immigrant refugees and their surrounding communities in developing countries. Evaluating the treatment outcome of TB patients is one of the key indicators to understand the performance of TB control program. Hence, this study aims to assess profile, treatment outcome and factors associated with unsuccessful outcome of TB patients treated under the TB control program among refugees and their surrounding communities (SCs) in Gambella Regional State, Ethiopia. METHODOLOGY: Retrospective study was conducted in the health facilities of refugee and their SCs in Gambella Regional State from March 1 to May 30, 2017. Demographic and related data of all TB patients registered in TB Control Program between September, 2008 and October, 2017 in health facilities of refugee and the SCs was extracted using data extraction format. Eight years trend of TB, treatment outcome and factors associated with unsuccessful outcome among refugees and the SCs were computed using SPSS version 20.0 software. RESULT: A total of 886 refugees and 3284 SCs TB patients, registered for anti TB treatment in the last eight years, were evaluated in the study. The trend of all forms of TB is progressively increasing among refugees contrary to the SCs in the course of the study period (X2 trend = 207.7; P<0.0001). Smear positive pulmonary TB (PTB+) was found to be predominant (57.6%) TB form in refugees while smear negative pulmonary TB (PTB-) (44.8%) is in the SCs (X2 = 185.834; P<0.0001). There was also significant difference in the treatment outcome (X2 = 170.915; P<0.0001). Mean treatment success rate was 74.2% and 88.1% for refugees and the SCs, respectively (X2 = 92.887; P<0.0001). The study also revealed that the risk of unsuccessful TB treatment outcome was significantly higher among refugee (AOR = 2.17; 95% CI: 1.69-2.77), retreated cases (AOR = 1.53; 95% CI: 1.07-2.17), patients aged between 35-44 years (AOR = 1.38; 95% CI: 1.0-1.91), and greater than 44 years old (AOR = 1.77; 95% CI: 1.28-2.44), and patients with extra pulmonary TB (EPTB) form (AOR = 1.34; 95% CI: 1.04-1.73) compared to their counterparts. Patient coming from rural area (AOR = 0.77; 95% CI: 0.62-0.97), who are female (AOR = 0.76; 95% CI: 0.63-0.91) and TB/HIV non-infected (AOR = 0.63; 95% CI: 0.51-0.77) were more likely to be successfully treated. CONCLUSION: The study confirmed that there was low treatment success rate among refugees compared to the SCs. Being refugee, retreated case, patient's age ≥35 years old, EPTB form, gender, rural patient address and HIV status were predictor factors for unsuccessful treatment outcome. Hence, the study urges the need for strengthened TB prevention program among refugees with due consideration of identified predictor factors to prevent the potential effect of hosting refugee to the SCs and the nations at large.