First Nationwide Survey of the Prevalence of TB/HIV Co-Infection in Ghana

Background: To better understand the extent of the magnitude of tuberculosis (TB) and Human Immunodeficiency Virus (HIV) co-infection in Ghana, a baseline study was conducted to establish the national prevalence of the dual infection. The study aimed to determine the most prevalent HIV serotype (HIV-1 or HIV-2) in TB patients (new and old cases);genotype mycobacterial species causing TB/HIV co-infection and determine their drug susceptibility patterns. Methods: Sputum and dried blood samples were collected from 503 TB patients from 67 health facilities nationwide between December 2007 and November 2008. All samples were processed for mycobacterial and HIV testing using conventional and molecular methods. Results: A total of 517 paired sputum samples were received from 517 patients. A total 503 patients [335 (66.6%) males;168 (33.4%) females] had at least one culture positive sample. Majority (93.0%) of the patients were new cases while 7.0% were old cases. All 503 TB isolates were Mycobacterium tuberculosis complex. Of 503 blood samples, 74 were positive for HIV (14.7%), comprising 71 (14.1%) and 3 (0.6%) for HIV-1 and HIV-1 & 2 respectively;none was positive for HIV-2 alone. The seroprevalence of HIV in newly diagnosed TB patients and those already on treatment, was 69/468 (14.7%) and 5/35 (14.3%) respectively (p > 0.05). Differentiation of isolates from TB/HIV co-infected patients showed that 70/74 (94.6%) were Mycobacterium tuberculosis while 4/74 (5.4%) were Mycobacterium africanum. Monoresistance to isoniazid and rifampicin were 4/74 (5.4%) and 1/74 (1.4%) respectively;resistance to both drugs (multi-drug resistant-MDR) was not observed. Sixty nine (93.2%) isolates were susceptible to both drugs. Conclusion: The prevalence of HIV infection in TB patients was 14.7%. TB/HIV was common among the sexually active age group (25 - 34 years). Majority of the TB isolates were M. tuberculosis which were susceptible to both isoniazid and rifampicin. HIV-1 was the common serotype infecting TB patients in Ghana.

Population-Based Tuberculosis Disease Prevalence Survey in Ghana: The Role and Lessons Learnt from the Laboratory

Background: Bacteriologically-confirmed tuberculosis (TB) cases used in calculating TB prevalence in a country are obtained through laboratory examination of sputum specimens. Objective: This article describes laboratory processing of specimens, results overview, conclusions and key lessons learnt from the perspective of laboratory personnel involved in the conduct of TB disease prevalence survey in Ghana in 2013. Methods: Symptoms screening and Chest X-ray suggestive of TB were used to select participants who produced sputum to confirm TB cases using microscopy, culture and Xpert®MTB/RIF assay (GeneXpert). Results: A total of 15,935 single and paired sputum specimens were received from eligible participants. About half of Ziehl-Nielsen (129/263) and Auramine O (122/246) stained smear positives were scanty positive. Culture positivity rate for Mycobacterium tuberculosis complex was 266/14,994 (1.7%) and 100/15,179 (0.7%) in Mycobacterial Growth Indicator Tube (MGIT) and Lowenstein-Jensen (LJ) media respectively;while non-tuberculous mycobacterium was 294/14,994 (1.96%) and 167/15,179 (1.1%). Total contamination rates in MGIT (5.4%) were higher than in LJ (1.7%). Prevalence of smear positive TB and bacteriologically confirmed TB among adult population (≥15 years) was estimated at 111 (95% CI: 76 - 145) and 356 (95% CI: 288 - 425) per 100,000 population respectively. Conclusions and Lessons Learnt: Direct supervision of specimen collection by well-trained laboratory personnel, timely transportation of specimens from field to laboratory, prompt specimen processing and use of electronic data management systems are essential for a reliable TB disease prevalence survey data. More importantly, strengthening human and logistical capacity of the laboratory must be of utmost priority.

First Nationwide Survey on the Resistance to First Line Anti-Tuberculosis Drugs in Ghana

Background/objective: A nationwide survey on the resistance to first line anti-tuberculosis (anti-TB) drugs was conducted in Ghana from 2007-2008 by Noguchi Memorial Institute for Medical Research in collaboration with the National Tuberculosis Control Programme. We aimed to characterize mycobacterial species causing pulmonary tuberculosis (PTB) and determine the resistance pattern to first line anti-TB drugs among newly diagnosed and previously treated PTB patients in Ghana. Methods: Two sputum samples from consented new smear positive PTB patients who had never been treated for TB or had been on anti-TB treatment for less than a month and patients who had been treated for TB previously for more than a month in selected diagnostic centres nationwide were collected for culture, identification and drug susceptibility test. Culture positive isolates were tested against streptomycin (S), isoniazid (H), rifampicin (R) and ethambutol (E) using the simplified proportion method and line probe assay (LPA). The LPA was performed in mid-2017. Results: Among 410 samples, 345 positive cultures were obtained and identified as Mycobacterium tuberculosis complex (MTBC). Of the 345 isolates, 133 were further differentiated by GenoType MTBC®as M. tuberculosis, 126 (94.7%) and M. africanum 7 (5.3%). The overall drug resistance patterns were as follows: 43/345 (12.5%), 6/345 (1.7%), 9/345 (2.6%) and 71/345 (20.6%) were resistant to H, R, E and S respectively and 5/345 (1.4%) were multi-drug resistant (MDR). Conclusion: The results indicate high levels of resistance to S and H among new and previously treated TB patients. We recommend adequate surveillance systems including periodic national anti-TB drug resistance surveys.