Mycobacterium tuberculosisis the causative agent of tuberculosis in the southern ecological zones of Cameroon, as shown by genetic analysis

BACKGROUND: Tuberculosis (TB) is a major cause of mortality and suffering worldwide, with over 95% of TB deaths occurring in low- and middle-income countries. In recent years, molecular typing methods have been widely used in epidemiological studies to aid the control of TB, but this usage has not been the case with many African countries, including Cameroon. The aims of the present investigation were to identify and evaluate the diversity of the Mycobacterium tuberculosis complex (MTBC) isolates circulating in two ecological zones of Cameroon, seven years after the last studies in the West Region, and after the re-organization of the National TB Control Program (NTBCP). These were expected to shed light also on the transmission of TB in the country. The study was conducted from February to July 2009. During this period, 169 patients with symptomatic disease and with sputum cultures that were positive for MTBC were randomly selected for the study from amongst 964 suspected patients in the savannah mosaic zone (West and North West regions) and the tropical rainforest zone (Central region). After culture and diagnosis, DNA was extracted from each of the MTBC isolates and transported to the BecA-ILRI Hub in Nairobi, Kenya for molecular analysis. METHODS: Genetic characterization was done by mycobacterial interspersed repetitive unit–variable number tandem repeat typing (MIRU-VNTR) and Spoligotyping. RESULTS: Molecular analysis showed that all TB cases reported in this study were caused by infections with Mycobacterium tuberculosis (98.8%) and Mycobacterium africanum (M. africanum) (1.2%) respectively. We did not detect any M. bovis. Comparative analyses using spoligotyping revealed that the majority of isolates belong to major clades of M. tuberculosis: Haarlem (7.6%), Latin American-Mediterranean (34.4%) and T clade (26.7%); the remaining isolates (31.3%) where distributed among the minor clades. The predominant group of isolates (34.4%) corresponded to spoligotype 61, previously described as the “Cameroon family. Further analysis based on MIRU-VNTR profiles had greater resolving power than spoligotyping and defined additional genotypes in the same spoligotype cluster. CONCLUSION: The molecular characterization of MTBC strains from humans in two ecological regions of Cameroon has shown that M. tuberculosis sensu stricto is the predominant agent of TB cases in the zones. Three decades ago, TB was reported to be caused by M. africanum in 56.0% of cases. The present findings are consistent with a major shift in the prevalence of M. tuberculosis in Cameroon

Is thyroid stimulating hormone titration mandatory in the routine work-up of African males from infertile couples?

Background: The impact of thyroid hormones on male reproductive function is still insufficiently understood. The objectives of this study were to determine the frequency of thyroid dysfunction in men from infertile couples and to establish an association between TSH (thyroid stimulating hormone) values and sperm parameters.Methods: We conducted a cross-sectional analytical study on a consecutive series of men managed for couple infertility in two reference hospitals of Yaoundé from November 2017 to May 2018. For each participant, a questionnaire was administered, TSH was assayed using electro-chemo-luminescence and sperm analyzed. Statistical methods used were the Mann-Whitney test and the Spearman correlation coefficient with a significance threshold of 5%.Results: Overall, 123 men were recruited. The median age was 44 years old [38-50 years]; 60 (48.79%) patients had couple infertility lasting between 1 and 5 years. Primary infertility of the couple was the most common (82 cases, 66.70%). After sperm analysis, 86 patients (70%) had one or more anomalies. TSH titration revealed 03 (2.44%) cases of subclinical hyperthyroidism, 05 (4.06%) subclinical hypothyroidism and 115 (93.50%) euthyroidism. Significant associations were found between TSH and sperm parameters in the group of patients with thyroid dysfunction, but none in the euthyroid group.Conclusions: Frequency of dysthyroidism is low among African males from infertile couples. We noted significant correlations between TSH values and sperm parameters. The low frequency of thyroid dysfunction would be against a TSH titration in the routine work-up of these patients

A new isoquinoline and ceramide from the stem barks of Discoglypremna caloneura (Pax) Prain (Euphorbiaceae) with antiproteinase and cytotoxic activities.

peer reviewedTwo new compounds, an isoquinoline (1) and caloneuramide (2), a ceramide were isolated from the stem bark of Discoglypremna caloneura together with seven known compounds namely aurantiamide acetate (3), acetylaleuritolic acid (4), 3α-hydroxylaleuritolic acid 2α-p-hydroxybenzoate (5), mixture of stigmasterol (6) and β-sitosterol (7), mixture of 7-oxo-stigmasterol (8) and 7-oxo-β-sitosterol (9). Their structures were determined based on data from literature and spectroscopic methods. Derivatization reactions on the isoquinoline led to two new compounds, the methylated (10) and acetylated (11) derivatives. Some compounds and extracts were evaluated for their cytotoxic and antiproteinase activity. Antiproteinase effect of compounds 1, 10 and 11 exhibited IC(50) values of 10.77, 1.19 and 3.61 μg/mL respectively; significantly low compared to the standard drug, acetyl salicylic acid (IC(50) = 20.28 μg/mL). Ethyl acetate and methanol extract exhibited moderate cytotoxicity activity on Chang liver cells with CC(50) values of 167.90 ± 2.20 and 106.30 ± 2.03 μg/mL compared to the reference drug cucurmin (CC(50) = 11.05 ± 1.04 μg/mL)

Portage vaginal et profil de sensibilité du Streptocoque du Groupe B Chez la femme enceinte à l'Hopital Gynéco-Obstétrique et Pédiatrique de Yaoundé (Yaoundé)

In order to obtain reliable data on vaginal carriage of Streptococcus agalactiae in pregnant women and to formulate a prevention program of neonatal Group B Streptococcus (GBS) disease, we carried out a prospective cross sectional study for 6 months. The general objective of the study was to evaluate the prevalence of vaginal carriage and the resistance profile of GBS. The study involved 142 pregnant women presenting for antenatal care in Yaoundé Gynecology-Obstetric and Pediatric Hospital (YGOPH). Participants were interviewed using a standard structure questionnaire. Low vaginal swabs were collected and cultured on specific media. A presumptive identification of isolates was made using standard bacteriological methods. Confirmative identification of Group B Streptococcus was done and antimicrobial sensitivity testing was performed. Among the 142 pregnant women GBS colonization was confirmed in 11 (7.7%). The rate of carriage was 3.8% in the first trimester, 7% in the second trimester and 11.1% in the third trimester. The predominant germ was Candida albicans with a frequency of 45.2% among the germs found in monomicrobial culture and Gardnerella vaginalis (77.8%) among the germs in polymicrobial culture, followed by Candida spp (11.8%), S. agalactiae (8.6%) and Escherichia coli (4.3%). The result of antimicrobial sensitivity testing showed that all the GBS strains were sensitive to major antibiotics drugs tested. The highest rates of resistance were found with gentamycin (100%) and Cefuroxim (81.8%). The vaginal carriage of GBS among pregnant women is still high. Thus, well-planned, prospective studies will be necessary to fully appreciate the magnitude of the problem of GBS in our hospitals

Chemiluminescence vs hemagglutination assay in the detection of Anti-Treponema pallidum antibodies

Background: Syphilis has serious consequences for human health and poses challenges for biological diagnosis. Techniques such as chemiluminescence are still poorly known in our context. Our objective was to compare chemiluminescence and hemagglutination assays with immunoblot as a reference test for detecting anti-Treponema pallidum antibodies. Methods: Anti-Treponema pallidum antibodies were detected in serum samples. Comparison of chemiluminescence and hemagglutination assays was carried out with immunoblot as the reference test, based on sensitivity, specificity, positive and negative predictive values, and kappa statistic, using IBM-SPSS version 24 software. The significance level was set at 5%. Results: A total of 600 participants were recruited, with a prevalence of syphilis infection of 3%. Sensitivity and specificity were 100% and 96.2% for chemiluminescence, and 93.8% and 100% for hemagglutination, respectively. Cohen's kappa statistic between the two tests showed satisfactory agreement (0.768). Cohen's kappa agreements between chemiluminescence/immunoblot and plate hemagglutination assay/immunoblot were greater than 0.8, indicating excellent agreement with the reference test (p<0.0001). Conclusion: Chemiluminescence is more sensitive but less specific than hemagglutination. The use of chemiluminescence as a first-line test for the diagnosis of syphilis should be considered