Mycobacterium tuberculosis resistance in pulmonary TB patients in Cameroon: a phenotypic susceptibility assay.

OBJECTIVE: To determine the resistance of Mycobacterium tuberculosis to first- and second-line agents in adult pulmonary tuberculosis (TB) patients in Cameroon using a novel phenotypic assay. SETTING: Samples were collected from TB patients at Bamenda Hospital in Bamenda, Cameroon. DESIGN: Samples were collected consecutively from adult pulmonary TB patients over a 2-month period. TREK Sensititre(TM) MYCOTB panels were used to perform phenotypic drug susceptibility testing (DST). Susceptibility/resistance was determined by comparing minimum inhibitory concentrations to standard critical concentrations established for first- and second-line anti-tuberculosis drugs. RESULTS: Of 103 sputum samples processed, growth on Löwenstein-Jensen media was confirmed in 78 samples, 65 of which were suitable for DST. Thirty-nine strains (60%) were susceptible to all first- and second-line drugs. Five strains (8%) were categorized as multidrug-resistant TB. Two strains (3%) were classified as pre-extensively drug-resistant TB. Of those isolates susceptible to first-line drugs, 20% were resistant to at least one second-line drug. CONCLUSION: Antimicrobial resistance may be higher than assumed in TB strains in Cameroon, especially with regard to second-line drugs. There remains a need for rapid, comprehensive DST.

Virological failure after 1 year of first-line ART is not associated with HIV minority drug resistance in rural Cameroon .

OBJECTIVES: The aim of this study was to describe clinical and virological outcomes in therapy-naive HIV-1-positive patients treated in a routine ART programme in rural Cameroon. METHODS: In a prospective cohort, 300 consecutive patients starting first-line ART were enrolled and followed for 12 months. Among 238 patients with available viral load data at Month 12, logistic regression was used to analyse risk factors for virological failure (≥1000 HIV RNA copies/mL) including clinical, immunological and virological parameters, as well as data on drug adherence. Population sequencing was performed to detect the presence of drug-resistance mutations in patients with virological failure at Month 12; minority drug-resistance mutations at baseline were analysed using next-generation sequencing in these patients and matched controls. RESULTS: At Month 12, 38/238 (16%) patients experienced virological failure (≥1000 HIV RNA copies/mL). Patients with virological failure were younger, had lower CD4 cell counts and were more often WHO stage 3 or 4 at baseline. Sixty-three percent of patients with virological failure developed at least one drug-resistance mutation. The M184V (n = 18) and K103N (n = 10) mutations were most common. At baseline, 6/30 patients (20%) experiencing virological failure and 6/35 (17%) matched controls had evidence of minority drug-resistance mutations using next-generation sequencing (P = 0.77). Lower CD4 count at baseline (OR per 100 cells/mm(3) lower 1.41, 95% CI 1.02-1.96, P = 0.04) and poorer adherence (OR per 1% lower 1.05, 95% CI 1.02-1.08, P < 0.001) were associated with a higher risk of virological failure. Unavailability of ART at the treatment centre was the single most common cause for incomplete adherence. CONCLUSIONS: Virological failure after 1 year of ART was not associated with minority drug resistance at baseline but with incomplete adherence. Strategies to assure adherence and uninterrupted drug supplies are pivotal factors for therapy success.

High HIV prevalence among children presenting for general consultation in rural Cameroon.

Data on the HIV-prevalence children presenting to health care facilities in sub-Saharan Africa are scant in general, and the debate about opportunities for paediatric HIV screening is ongoing. Nine hundred and eighty-one children with unknown HIV-status presenting to a large general paediatric outpatient department in rural Cameroon were tested using the Determine HIV-1/2 rapid test (Abbott), and positive results were confirmed with the Hexagon HIV rapid test (Human Diagnostics). In children younger than 18 months, HIV infection was confirmed by PCR testing. Median age was 1.3 years and 52.8% were of male gender. In 514 children below 18 months of age, 16 (3.1%) tested positive. Of those, HIV-1 PCR was available for 11 children, of whom 6 had a positive PCR result. HIV prevalence was highest in the age group 5-9 years, being 8.8%. Malnutrition (33.3 vs 5.2%, p < 0.001) was associated with HIV infection. Our study results indicate that HIV testing should be offered to all children at possible entry points to medical care, irrespective of symptoms, in order to reduce HIV-associated mortality through timely initiation of antiretroviral therapy.

High prevalence of hepatitis B and syphilis co-infections among HIV patients initiating antiretroviral therapy in the north-west region of Cameroon.

Hepatitis B virus (HBV) and syphilis co-infections contribute significantly to HIV-associated morbidity and mortality, but the burden of these diseases is not fully appreciated in sub-Saharan Africa, as prevalence data are scarce. Both infections often remain undiagnosed in resource-limited settings because routine testing is not a part of most of the national guidelines. Epidemiological studies provide important information on prevalence and risk factors for such co-infections and can provide guidance for clinical management and for the development of test strategies. We analysed data on baseline characteristics, CD4 cell counts, HBV and syphilis co-infection rates of 690 patients enrolling for antiretroviral therapy in rural Cameroon. The prevalence of both hepatitis B surface antigen (HBsAg, 12.6%, 95% CI 10.1-15.1) and treponemal antibodies (11.4%, 95% CI 8.9-13.7) was high, with significantly higher prevalences for both infections in men; detection of treponemal antibodies increased with age. Although liver enzyme elevations were common, they were not useful to identify HBsAg-positive patients. In this setting, routine serological screening for HBV and syphilis co-infection should be considered to avoid complications and ongoing transmission.