Ponsiano Ocama
Makerere University
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Featured researches published by Ponsiano Ocama.
Liver International | 2011
Steven T. Wiersma; Brian J. McMahon; Jean-Michel Pawlotsky; Chloe L. Thio; Mark Thursz; Seng Gee Lim; Ponsiano Ocama; Gamal Esmat; Mendy Maimuna; David M. Bell; Marco Vitoria; Irina Eramova; Daniel Lavanchy; Geoff Dusheiko
Most of the estimated 350 million people with chronic hepatitis B virus (HBV) infection live in resource‐constrained settings. Up to 25% of those persons will die prematurely of hepatocellular carcinoma (HCC) or cirrhosis. Universal hepatitis B immunization programmes that target infants will have an impact on HBV‐related deaths several decades after their introduction. Antiviral agents active against HBV are available; treatment of HBV infection in those who need it has been shown to reduce the risk of HCC and death. It is estimated that 20–30% of persons with HBV infection could benefit from treatment. However, drugs active against HBV are not widely available or utilized in persons infected with HBV. Currently recommended antiviral agents used for treatment of human immunodeficiency virus (HIV) infection do not adequately suppress HBV, which is of great concern for the estimated 10% of the HIV‐infected persons in Africa who are co‐infected with HBV. Progressive liver disease has been shown to occur in co‐infected persons whose HBV infection is not suppressed. In view of these concerns, an informal World Health Organization consultation of experts concluded that: chronic HBV is a major public health problem in emerging nations; all HIV‐infected persons should be screened for HBV infection; HIV/HBV co‐infected persons should be treated with therapies active against both viruses and that reduce the risk of resistance; standards for the management of chronic HBV infection should be adapted to resource‐constrained settings. In addition, a research agendum was developed focusing on issues related to prevention and treatment of chronic HBV in resource‐constrained settings.
Antiviral Therapy | 2011
Lara Stabinski; Steven J. Reynolds; Ponsiano Ocama; Oliver Laeyendecker; Anthony Ndyanabo; Valerian Kiggundu; Iga Boaz; Ronald H. Gray; Maria J. Wawer; Chloe L. Thio; David L. Thomas; Thomas C. Quinn; Gregory D. Kirk
BACKGROUND Liver disease is a leading cause of mortality among HIV-infected persons in the United States and Europe. However, data regarding the effects of HIV and antiretroviral therapy (ART) on liver disease in Africa are sparse. METHODS A total of 500 HIV-infected participants in an HIV care programme in rural Rakai, Uganda were frequency-matched by age, gender and site to 500 HIV-uninfected participants in a population cohort. All participants underwent transient elastography (FibroScan(®)) to quantify liver stiffness measurements (LSM) and identify participants with significant liver fibrosis, defined as LSM≥9.3 kPa (≈ Metavir F≥2). Risk factors for liver fibrosis were identified by estimating adjusted prevalence risk ratios (adjPRR) and 95% CI using modified Poisson multivariate regression. RESULTS The prevalence of hepatitis B coinfection in the study population was 5%. The prevalence of significant fibrosis was 17% among HIV-infected and 11% in HIV-uninfected participants (P=0.008). HIV infection was associated with a 50% increase in liver fibrosis (adjPRR 1.5, 95% CI 1.1-2.1; P=0.010). Fibrosis was also associated with male gender (adjPRR 1.4, 95% CI 1.0-1.9; P=0.045), herbal medicine use (adjPRR 2.0, 95% CI 1.2-3.3; P=0.005), heavy alcohol consumption (adjPRR 2.3, 95% CI 1.3-3.9; P=0.005), occupational fishing (adjPRR 2.5, 95% CI 1.2-5.3; P=0.019) and chronic HBV infection (adjPRR 1.7, 95% CI 1.0-3.1; P=0.058). Among HIV-infected participants, ART reduced fibrosis risk (adjPRR 0.6, 95% CI 0.4-1.0; P=0.030). CONCLUSIONS The burden of liver fibrosis among HIV-infected rural Ugandans is high. These data suggest that liver disease may represent a significant cause of HIV-related morbidity and mortality in Africa.
Clinical Infectious Diseases | 2013
Caroline E. Mullis; Oliver Laeyendecker; Steven J. Reynolds; Ponsiano Ocama; Jeffrey Quinn; Iga Boaz; Ronald H. Gray; Gregory D. Kirk; David L. Thomas; Thomas C. Quinn; Lara Stabinski
The prevalence of hepatitis C virus (HCV) infection in sub-Saharan Africa remains unclear. We tested 1000 individuals from Rakai, Uganda, with the Ortho version 3.0 HCV enzyme-linked immunosorbent assay. All serologically positive samples were tested for HCV RNA. Seventy-six of the 1000 (7.6%) participants were HCV antibody positive; none were confirmed by detection of HCV RNA.
Journal of Medical Virology | 2010
E. Seremba; Ponsiano Ocama; Christopher Kenneth Opio; Magid Kagimu; Hejun Yuan; Nahid Attar; David L. Thomas; William M. Lee
Commercially available rapid strip assays (RSAs) for hepatitis B surface antigen (HBsAg) are used for most routine clinical testing in sub‐Saharan Africa. This study evaluated the validity of RSA and a more sophisticated enzyme immunoassay (EIA) with confirmation by nucleic acid testing (NAT) in hospitalized patients in Uganda. Sera from 380 consecutive patients collected and tested for HBsAg and anti‐HIV in Kampala, Uganda by RSA were sent frozen to Dallas for EIA including HBsAg, total anti‐hepatitis B core, hepatitis B e antigen, and anti‐HIV. NAT was performed on all HBsAg‐positives and on a random sample of 102 patients that were HBsAg‐negative by both assays. Overall, 31 (8%) were HBsAg positive by RSA while 50 (13%) were HBsAg‐positive by EIA; 26 were concordant between the two assays. Of 55 HBsAg‐positive patients, nearly all showed detectable serum hepatitis B virus (HBV) DNA by bDNA (46) or PCR (4) assay. The 26 patients who were HBsAg positive by both EIA and RSA had significantly higher median serum HBV DNA levels than the 24 patients who were HBsAg positive by EIA alone. An additional 12/102 (12%) HBsAg negative patients had very low serum HBV DNA levels by NAT. Several differences in expected results of serologic testing were observed in this large series of African patients. RSA HBsAg testing is less sensitive than EIA; even EIA failed to detect all HBV DNA positive sera. A more complex testing protocol than RSA alone will be needed in Africa to improve patient care. J. Med. Virol. 82:1334–1340, 2010.
Clinical Infectious Diseases | 2007
Patricia Mwebaze Songa; Barbara Castelnuovo; Estella Birabwa Mugasha; Ponsiano Ocama; Andrew Kambugu
We describe 24 Ugandan patients with human immunodeficiency virus infection who developed symptomatic hyperlactatemia associated with the use of nucleoside analogues. All patients were receiving combination therapy that contained stavudine. The median serum lactate level was 6.6 mmol/L. All patients had their antiretroviral treatment regimen discontinued. Hospital admission was required for 5 patients. Five patients died.
Journal of Medical Virology | 2010
Emmanuel Seremba; Ponsiano Ocama; Christopher Kenneth Opio; Magid Kagimu; David L. Thomas; H.J. Yuan; N. Attar; William M. Lee
Most hepatitis C testing in Uganda is performed using commercial rapid strip assays (RSA) to detect antibodies to hepatitis C virus (anti‐HCV), rather than enzyme immunoassays (EIA). The prevalence of hepatitis C antibodies in a Ugandan hospital population was determined using both methods to test their accuracy using nucleic acid testing (NAT) as a reference. Sera from 380 consecutive hospitalized Ugandan patients were tested for anti‐HCV using an RSA in Uganda, with subsequent automated third‐generation EIA testing in the United States, followed by NAT. Recombinant immunoblot assays (RIBA) were used as a supplementary test to detect anti‐HCV epitopes. Overall, anti‐HCV was detected in 48/380 (13%) by one or both antibody tests. Anti‐HCV was detected in 19 (5.0%) patients by RSA and in 33 (8.7%) patients by EIA; only four patients were anti‐HCV positive by both methods. Fourteen of the 48 anti‐HCV positive patients had detectable serum HCV RNA, 7 each by bDNA assay or by PCR. RSA detected only 7 of 14 HCV RNA positive sera. Of 29 RNA negative but anti‐HCV positive patients tested by RIBA, only two were anti‐HCV positive; 27 were anti‐HCV negative or indeterminate. Anti‐HCV testing by RSA and/or EIA was neither sensitive nor specific for detection of ongoing HCV infection in hospitalized Ugandan patients. Our findings underscore the importance of confirmatory nucleic acid testing, which, despite its increased cost, appears essential to manage African patients with HCV. J. Med. Virol. 82:1371–1378, 2010.
British Journal of Cancer | 2009
Ponsiano Ocama; Sarah Nambooze; C K Opio; M S Shiels; Henry Wabinga; G D Kirk
Primary liver cancer (PLC) incidence trends from Africa are unknown. Using Kampala Cancer Registry data from 1960 to 1980 and 1991 to 2005, we identified 771 PLCs. Although rates were stable among men, PLC incidence among women increased >50%. Investigations of viral hepatitis, aflatoxin, obesity, and human immunodeficiency virus (HIV) may help to explain the increasing incidence of hepatocellular carcinomas (HCCs).
The Lancet Gastroenterology & Hepatology | 2017
Ju Dong Yang; Essa A. Mohamed; Ashraf Omar Abdel Aziz; Hend Ibrahim Shousha; Mohamed B. Hashem; Mohamed Mahmoud Nabeel; Ahmed H. Abdelmaksoud; Tamer Elbaz; Mary Afihene; Babatunde M. Duduyemi; Joshua P. Ayawin; Adam Gyedu; Marie Jeanne Lohouès-Kouacou; Antonin W Ndjitoyap Ndam; Ehab F. Moustafa; Sahar M. Hassany; Abdelmajeed M. Moussa; Rose Ashinedu Ugiagbe; Casimir Omuemu; Richard Anthony; Dennis Palmer; Albert F. Nyanga; Abraham O. Malu; Solomon Obekpa; Abdelmounem E. Abdo; Awatif I. Siddig; Hatim Mudawi; Uchenna Okonkwo; Mbang Kooffreh-Ada; Yaw A. Awuku
BACKGROUND Hepatocellular carcinoma is a leading cause of cancer-related death in Africa, but there is still no comprehensive description of the current status of its epidemiology in Africa. We therefore initiated an African hepatocellular carcinoma consortium aiming to describe the clinical presentation, management, and outcomes of patients with hepatocellular carcinoma in Africa. METHODS We did a multicentre, multicountry, retrospective observational cohort study, inviting investigators from the African Network for Gastrointestinal and Liver Diseases to participate in the consortium to develop hepatocellular carcinoma research databases and biospecimen repositories. Participating institutions were from Cameroon, Egypt, Ethiopia, Ghana, Ivory Coast, Nigeria, Sudan, Tanzania, and Uganda. Clinical information-demographic characteristics, cause of disease, liver-related blood tests, tumour characteristics, treatments, last follow-up date, and survival status-for patients diagnosed with hepatocellular carcinoma between Aug 1, 2006, and April 1, 2016, were extracted from medical records by participating investigators. Because patients from Egypt showed differences in characteristics compared with patients from the other countries, we divided patients into two groups for analysis; Egypt versus other African countries. We undertook a multifactorial analysis using the Cox proportional hazards model to identify factors affecting survival (assessed from the time of diagnosis to last known follow-up or death). FINDINGS We obtained information for 2566 patients at 21 tertiary referral centres (two in Egypt, nine in Nigeria, four in Ghana, and one each in the Ivory Coast, Cameroon, Sudan, Ethiopia, Tanzania, and Uganda). 1251 patients were from Egypt and 1315 were from the other African countries (491 from Ghana, 363 from Nigeria, 277 from Ivory Coast, 59 from Cameroon, 51 from Sudan, 33 from Ethiopia, 21 from Tanzania, and 20 from Uganda). The median age at which hepatocellular carcinoma was diagnosed significantly later in Egypt than the other African countries (58 years [IQR 53-63] vs 46 years [36-58]; p<0·0001). Hepatitis C virus was the leading cause of hepatocellular carcinoma in Egypt (1054 [84%] of 1251 patients), and hepatitis B virus was the leading cause in the other African countries (597 [55%] of 1082 patients). Substantially fewer patients received treatment specifically for hepatocellular carcinoma in the other African countries than in Egypt (43 [3%] of 1315 vs 956 [76%] of 1251; p<0·0001). Among patients with survival information (605 [48%] of 1251 in Egypt and 583 [44%] of 1315 in other African countries), median survival was shorter in the other African countries than in Egypt (2·5 months [95% CI 2·0-3·1] vs 10·9 months [9·6-12·0]; p<0·0001). Factors independently associated with poor survival were: being from an African countries other than Egypt (hazard ratio [HR] 1·59 [95% CI 1·13-2·20]; p=0·01), hepatic encephalopathy (2·81 [1·72-4·42]; p=0·0004), diameter of the largest tumour (1·07 per cm increase [1·04-1·11]; p<0·0001), log α-fetoprotein (1·10 per unit increase [1·02-1·20]; p=0·0188), Eastern Cooperative Oncology Group performance status 3-4 (2·92 [2·13-3·93]; p<0·0001) and no treatment (1·79 [1·44-2·22]; p<0·0001). INTERPRETATION Characteristics of hepatocellular carcinoma differ between Egypt and other African countries. The proportion of patients receiving specific treatment in other African countries was low and their outcomes were extremely poor. Urgent efforts are needed to develop health policy strategies to decrease the burden of hepatocellular carcinoma in Africa. FUNDING None.
The American Journal of Gastroenterology | 2015
Ju Dong Yang; Adam Gyedu; Mary Afihene; Babatunde M. Duduyemi; Eileen Micah; T. Peter Kingham; Mulinda Nyirenda; Adwoa Agyei Nkansah; Salome Bandoh; Mary J. Duguru; En Okeke; Marie-Jeanne Kouakou-Lohoues; Abdelmounem E. Abdo; Yaw A. Awuku; Akande Oladimeji Ajayi; Abidemi Omonisi; Ponsiano Ocama; Abraham O. Malu; Shettima Mustapha; Uchenna Okonkwo; Mbang Kooffreh-Ada; Jose D. Debes; Charles A. Onyekwere; Francis Ekere; Igetei Rufina; Lewis R. Roberts
Hepatocellular Carcinoma Occurs at an Earlier Age in Africans, Particularly in Association With Chronic Hepatitis B
International Journal of Std & Aids | 2010
Ponsiano Ocama; Barbara Castelnuovo; Moses R. Kamya; G D Kirk; Steven J. Reynolds; Agnes Kiragga; Robert Colebunders; David L. Thomas
Liver enzyme elevations among patients on antiretroviral therapy (ART) were determined by prospectively evaluating aspartate aminotransferase (AST) data in a cohort of patients in Kampala over 36 months. A proportion of patients had hepatitis B virus (HBV) status determined. Hepatotoxicity was graded I to IV according to the AIDS Clinical Trial Group criteria. Of 546 patients, 377 (69%) were women; overall median baseline CD4+ T-cell was 97/μL (interquartile range [IQR] 20–164). Hepatitis B surface antigen (HBsAg) was detected in 42 (9%) of 470 persons. ART included lamivudine, with either nevirapine and d4T (74%) or efavirenz and AZT (26%). Median (IQR) AST level at baseline was 35 (27, 53 IU/L). Over 36 months, only eight patients had grade III AST elevation. Neither HBsAg nor ART regimen influenced AST levels. Male gender and CD4+ change from baseline were correlated with AST elevation. Patients with HIV/HBV co-infection were not at an increased risk of AST elevation, which occurred uncommonly in this setting.