Evaluation of GeneXpert MTB/RIF system performances in the diagnosis of extrapulmonary tuberculosis.

BACKGROUND: Tuberculosis represents a serious public health problem and a significant diagnostic and therapeutic challenge worldwide. Molecular diagnostic techniques are crucial in the World Health Organization's new tuberculosis control strategy. This study aims to evaluate the performance of GeneXpert MTB/RIF (Cepheid Sunnyvale, CA, United States) in diagnosis of extra-pulmonary tuberculosis then compare it's performance in detecting Rifampicin resistance to GenoType MTBDRplus (HAIN Life Sciences, Nehren, Germany). METHODS: Samples from pulmonary and/or extra-pulmonary origins were analysed in a 21 months retrospective study. Samples were sent to the bacteriology laboratory for Mycobacterium tuberculosis detection using conventional bacteriological and molecular methods (GeneXpert MTB/RIF and MTBDRplus). Sensitivity and specificity were calculated for the stained smear and GeneXpert according to culture (Gold Standard) as well as for GeneXpert MTB/RIF in both negative and positive microscopy tuberculosis cases. Data's statistical analysis was performed with SPSS13.0 software. RESULTS: Seven hundred fourteen patients' samples were analysed; the average age was 47.21 ± 19.98 years with a male predominance (66.4%). Out of 714 samples: 285 were from pulmonary and 429 were from extra-pulmonary origins. The positivity rates for microscopy, GeneXpert MTB/RIF and culture were 12.88, 20.59 and 15.82%, respectively. These rates were 18.9, 23.85 and 20.35% for pulmonary samples and 9.71, 18.41 and 12.82% for extra-pulmonary samples, respectively. The sensitivity and specificity of GeneXpert MTB/RIF were almost the same in both pulmonary and extra-pulmonary samples (78.2 and 90.4%) and (79,3 and 90.3%) respectively. Rifampicin resistance rate found by GeneXpert MTB/RIF was 0.84%. Comparison of Rifampicin resistance obtained by GeneXpert MTB/RIF and Genotype MTBDRplus, showed 100% agreement between the two techniques for studied samples. CONCLUSIONS: This confirms GeneXpert MTB/RIF advantage for tuberculosis diagnosis, particularly extra-pulmonary tuberculosis with negatively stained smear. The performance of GeneXpert and Genotype MTBDRplus are similar in detection of Rifampicin resistance. However, variability of detection performance according to tuberculosis endemicity deserves more attention in the choice of screening techniques of Rifampicin resistance, hence the interest of conducting comparative studies of detection performance under low and medium endemicity on large samples of tuberculosis populations.

Multidrug-resistant community-acquired urinary tract infections in a northern region of Morocco: epidemiology and risk factors.

INTRODUCTION: Urinary tract infection is very common and is the second most frequent reason for consultation in office-based practice. The incidence varies from one country to another. The diffusion of MDR in the community complicates therapeutic management. The objective of this study was to describe the bacterial epidemiology and to determine the risk factors for the acquisition of MDR in community urinary tract infections in our region. METHODS: This was a retrospective case-control study conducted in the bacteriology laboratory of the Mohammed V Military Teaching Hospital over an 8-month period from 01 October 2015 to 31 May 2016. Cases were defined as patients with community-acquired urinary tract infection with MDR and controls were defined as patients with a urinary tract infection without MDR. RESULTS: Out of 373 isolates, enterobacteria represented 80%. E. coli represented 59.2%, followed by K. pneumoniae at 15%. The rate of MDR represented 13.4% of which ESBL enterobacteria represented 12.1%. Univariate analysis showed a statistically significant association between male sex (p=0.001), age >65 years (p=0.007), urban origin (p=0.003), previous hospitalization within 3 months (p=0.001) and antibiotic therapy within 6 months (p=0.001) with MDR community-acquired urinary tract infection. On the other hand, multivariate analysis by logistic regression showed that age >65 years (OR=8.4, CI: 2.1-42), previous hospitalization within 3 months (OR=13.4, CI: 3.3-140.2) and antibiotic therapy within 6 months (OR=9.2, CI: 4.1-60.1) were significantly associated to MDR community-acquired urinary tract infection. CONCLUSIONS: The increase in resistance to enterobacteria in the community prompts a review of the list of antibiotics prescribed for probabilistic management of these infections in our region.

Update on the resistance of Escherichia coli isolated from urine specimens in a Moroccan hospital: a review of a 7-year period.

INTRODUCTION: Escherichia coli is the most commonly isolated species in both community and healthcare-associated infections. Our study's purpose was to determine the rates of antibiotic resistance of E. coli isolates in hospital and community populations, track the kinetics of resistance rates of E. coli isolates to major antibiotics, particularly those prescribed for urinary tract infections and study the occurrence and evolution of multi-resistant phenotypes. METHODS: We conducted a retrospective study at the Bacteriological Department of the Mohammed V Military Hospital of Instruction, over a period of 7 years. All isolates of E. coli from inpatients and outpatients were included. Identification of bacterial isolates was based on culture, morphological and biochemical identification characteristics. Antibiotic susceptibility was studied using the Mueller Hilton agar diffusion method by using OXOID® type antibiotic discs and interpreted according to the recommendations of EUCAST/CA-SFM 2019. RESULTS: The rate of resistance of E. coli isolates to 3rd generation cephalosporins, imipenem and fluoroquinolones was 12%, 1% and 34%, respectively. The difference between the resistance rates of inpatient and outpatient E. coli isolates was statistically significant for most antibiotics (p<0.05). The rate of extended-spectrum beta-lactamase phenotype (ESBL) was 6.73%. The carbapenemase phenotype was 1.25%. The ESBL phenotype rate increased from 3% in 2012 to 11.16% in 2018. CONCLUSIONS: The progression of the ESBL phenotype in both hospital and community settings, due to the increase in the resistance rate to 3rd generation cephalosporin, is prompting a review of the strategy for the therapeutic management of urinary tract infections with these molecules as probabilistic treatment.

Unexpected discovery of hemoglobinopathy C/ß° thalassemia.

High performance liquid chromatography (HPLC) is the current method of choice for the detection of hemoglobinopathies and the quantification of A2 and fetal hemoglobin. We are describing a case where a double heterozygosity C/beta-thalassemia was fortuitously identified, during assaying HBA1c, by HPLC.

Infectious aneurysm of the two primary iliac arteries: rare localization of Salmonella typhimurium infection.

Infectious aneurysm is a severe entity of the aneurysmal pathology, due essentially to a bacterial agent. The most frequently implicated organisms are salmonella and staphylococci. We report the case of an infectious aneurysm of the two primitive iliac arteries with Salmonella typhimurium in a 70-year-old man.