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1.
J Infect Dis ; 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38332750

RESUMEN

In Lusaka, Zambia, we introduced liver fine needle aspiration (FNA) into a research cohort of adults with treatment-naïve chronic hepatitis B virus (HBV) infection, with and without HIV coinfection, as well as with acute HBV infection. Over 117 enrollment and 47 longitudinal FNAs (at 1 year follow-up), we established participant acceptability and safety. We also demonstrated the quality of the material through single cell RNA sequencing of selected enrollment FNAs, which revealed a range of immune cells. This approach can drive new insights into HBV immunology, informing cure strategies, and can improve our understanding of HBV natural history in Africa.

2.
Therap Adv Gastroenterol ; 16: 17562848231184986, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37457138

RESUMEN

With the exception of South Africa, inflammatory bowel disease (IBD) has long been considered uncommon in sub-Saharan Africa (SSA) with a dearth of peer-reviewed publications from the subcontinent. This most likely reflects underreporting as some cases may be missed due to the high burden of infectious diseases which may closely mimic IBD. In addition, many countries in SSA have limited endoscopic capacity, inadequate access to diagnostic imaging and a notable scarcity of histopathologists, radiologists and gastroenterologists. Beyond these obstacles, which significantly impact patient care, there are many other challenges in SSA, particularly the unavailability of key IBD therapies. In this review, we discuss barriers in diagnosing and managing IBD in SSA, as well as some of the initiatives currently in place to address these short comings.

3.
AIDS ; 37(13): 2015-2020, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37467044

RESUMEN

BACKGROUND: To inform novel therapies, a more nuanced understanding of HIV's impact on hepatitis B virus (HBV) natural history is needed, particularly in high burden countries. METHODS: In Lusaka, Zambia, we compared prospectively recruited adults (18+ years) with chronic HBV infection, with and without HIV. We excluded those with prior antiviral treatment experience or HBV diagnosis due to clinical suspicion (rather than routine testing). We assessed HBV DNA levels, hepatitis B e antigen (HBeAg), CD4 + (if HIV coinfection), and liver disease (transient elastography, serum alanine aminotransferase). In multivariable analyses, we evaluated the association of HIV overall and by level of CD4 + count on these markers. RESULTS: Among 713 adults analyzed, median age was 33 years, 63% were male, and 433 had HBV/HIV coinfection. Median CD4 + count was 200 cells/µl. HBV DNA was greater than 2000 IU/ml for 311 (51.0%) and 227 (32.5%) were HBeAg-positive. 15.5% had advanced fibrosis or cirrhosis. HIV coinfection was associated with five-fold increased HBV DNA levels [adjusted geometric mean ratio, 5.78; 95% confidence interval (CI), 2.29-14.62] and two times the odds of HBeAg-positivity (adjusted odds ratio, 2.54; 95% CI, 1.59-4.08). These associations were significant only at CD4 + counts 100-350 and <100 cells/µl. HIV was not associated with markers of fibrosis or ALT. DISCUSSION: HIV's impact on HBV natural history likely depends on the degree and duration of immune suppression. There is strong rationale to monitor HBV DNA in people with HBV/HIV coinfection and immune suppression. A better understanding is needed of mechanisms of increased liver-related mortality in people with HBV/HIV coinfection.


Asunto(s)
Coinfección , Infecciones por VIH , Hepatitis B Crónica , Hepatitis B , Adulto , Humanos , Masculino , Femenino , Hepatitis B Crónica/tratamiento farmacológico , Infecciones por VIH/tratamiento farmacológico , Antígenos e de la Hepatitis B/uso terapéutico , ADN Viral , Zambia/epidemiología , Virus de la Hepatitis B/genética , Cirrosis Hepática/complicaciones , Coinfección/tratamiento farmacológico , Replicación Viral , Hepatitis B/complicaciones
4.
BMC Gastroenterol ; 23(1): 66, 2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36906562

RESUMEN

BACKGROUND: The prevalence, management, and clinical outcomes of cholangiocarcinoma in Africa are unknown. The aim is to conduct a comprehensive systematic review on the epidemiology, management, and outcomes of cholangiocarcinoma in Africa. METHODS: We searched PubMed, EMBASE, Web of Science and CINHAL from inception up to November 2019 for studies on cholangiocarcinoma in Africa. The results reported follow PRISMA guidelines. Quality of studies and risk of bias were adapted from a standard quality assessment tool. Descriptive data were expressed as numbers with proportions and Chi-squared test was used to compare proportions. P values < 0.05 were considered significant. RESULTS: A total of 201 citations were identified from the four databases. After excluding duplicates, 133 full texts were reviewed for eligibility, and 11 studies were included. The 11 studies are reported from 4 countries only: 8 are from North Africa (Egypt 6 and Tunisia 2), and 3 in Sub-Saharan Africa (2 in South Africa, 1 in Nigeria). Ten studies reported management and outcomes, while one study reported epidemiology and risk factors. Median age for cholangiocarcinoma ranged between 52 and 61 years. Despite the proportion with cholangiocarcinoma being higher among males than females in Egypt, this gender disparity could not be demonstrated in other African countries. Chemotherapy is mainly used for palliative care. Surgical interventions are curative and prevent cancer progression. Statistical analyses were performed with Stata 15.1. CONCLUSION: The known global major risk factors such as primary sclerosing cholangitis, Clonorchis sinensis and Opisthorchis viverrini infestation are rare. Chemotherapy treatment was mainly used for palliative treatment and was reported in three studies. Surgical intervention was described in at least 6 studies as a curative modality of treatment. Diagnostic capabilities such as radiographic imaging and endoscopic are lacking across the continent which most likely plays a role in accurate diagnosis.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conductos Biliares Intrahepáticos , Factores de Riesgo , Sudáfrica
5.
Heliyon ; 6(7): e04534, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32760834

RESUMEN

Cirrhosis commonly complicates portal hypertension worldwide but in Zambia hepatosplenic schistosomiasis (HSS) dominates as the cause of portal hypertension. We need easier and non-invasive ways to assess HSS. Transient elastography (TE), a measure of liver stiffness can diagnose liver cirrhosis. TE remains unexplored in HSS patients, who generally have normal liver parenchyma. We aimed to explore liver stiffness in HSS. This nested case control study was conducted at the University Teaching Hospital, Lusaka, Zambia between January 2015 and January 2016. We enrolled 48 adults with HSS and 22 healthy controls. We assessed liver stiffness using TE while plasma hyaluronan was used to assess liver fibrosis. Plasma tumor necrosis factor receptor 1 (TNFR1) and soluble cluster of differentiation 14 (sCD14) were used to assess inflammation. The median (interquartile range) liver stiffness was higher in patients, 9.5 kPa (7.8, 12.8) than in controls, 4.7 kPa (4.0, 5.4), P < 0.0001. We noted linear correlations of hyaluronan and TNFR1 with the liver stiffness, P = 0.0307 and P = 0.0003 respectively. HSS patients seem to have higher liver stiffness than healthy controls. TE may be useful in identifying fibrosis in HSS. The positive correlations of inflammatory markers with TE suggest that HSS has both periportal and parenchymal pathophysiology.

6.
Am J Trop Med Hyg ; 102(4): 832-837, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32067625

RESUMEN

Hepatosplenic schistosomiasis (HSS) complicates portal hypertension, leading to life-threatening variceal bleeding. Variceal bleeding is associated with increased portal vein diameter (PVD). Beta-blockers prevent variceal bleeding. It is unclear whether beta-blockers such as propranolol can reduce PVD in HSS. We aimed to explore the effect of propranolol on PVD in HSS. A longitudinal study was conducted at the University Teaching Hospital, Zambia, as an extension of a clinical trial of rifaximin undertaken to test the hypothesis that rifaximin could reduce bacterial translocation in HSS. We randomized 85 adults to either rifaximin and standard care, or propranolol-based standard care only for 42 days. We then followed up all the patients on propranolol up to day 180. We used ultrasound to measure PVD at baseline and day 180. The primary outcome was reduction in PVD. Beta-blockade and splenic size reduction were secondary outcomes. Portal vein diameter reduced after 180 days of propranolol therapy from median 12 mm (interquartile range (IQR): 11-14) to median 10 mm (IQR: 9-13) (P < 0.001). The pulse rate reduced from baseline median 70 beats/minute (IQR: 66-80) to 65 beats/minute (IQR: 60-70) by day 180 (P = 0.006). Hemoglobin levels improved from baseline median 8 g/dL (IQR: 6-11) to 12 g/dL (10-14) (P < 0.001). Splenic size remained unchanged. Propranolol led to the reduction in PVD over 180 days. This suggests that ultrasound could be useful in monitoring response and compliance to beta-blockers, especially in resource-constraint areas where portal hypertension measurement facilities are unavailable.


Asunto(s)
Hipertensión Portal/etiología , Hepatopatías/tratamiento farmacológico , Hepatopatías/parasitología , Propranolol/uso terapéutico , Esquistosomiasis/complicaciones , Adulto , Antihelmínticos/uso terapéutico , Antibacterianos/uso terapéutico , Antihipertensivos/uso terapéutico , Femenino , Humanos , Hipertensión Portal/tratamiento farmacológico , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Vena Porta , Praziquantel/uso terapéutico , Estudios Prospectivos , Rifaximina/uso terapéutico
7.
PLoS One ; 15(1): e0227041, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31929556

RESUMEN

INTRODUCTION: We evaluated antiviral therapy (AVT) eligibility in a population-based sample of adults with chronic hepatitis B virus (HBV) infection in Zambia. MATERIALS AND METHODS: Using a household survey, adults (18+ years) were tested for hepatitis B surface antigen (HBsAg). Sociodemographic correlates of HBsAg-positivity were identified with multivariable regression. HBsAg-positive individuals were referred to a central hospital for physical examination, elastography, and phlebotomy for HBV DNA, hepatitis B e antigen, serum transaminases, platelet count, and HIV-1/2 antibody. We determined the proportion of HBV monoinfected adults eligible for antiviral therapy (AVT) based on European Association for the Study of the Liver (EASL) 2017 guidelines. We also evaluated the performance of two alternative criteria developed for use in sub-Saharan Africa, the World Health Organization (WHO) and Treat-B guidelines. RESULTS: Across 12 urban and 4 rural communities, 4,961 adults (62.9% female) were tested and 182 (3.7%) were HBsAg-positive, 80% of whom attended hospital follow-up. HBsAg-positivity was higher among men (adjusted odds ratio [AOR], 1.37; 95% confidence interval [CI], 0.99-1.87) and with decreasing income (AOR, 0.89 per household asset; 95% CI, 0.81-0.98). Trends toward higher HBsAg-positivity were also seen at ages 30-39 years (AOR, 2.11; 95% CI, 0.96-4.63) and among pregnant women (AOR, 1.74; 95% CI, 0.93-3.25). Among HBV monoinfected individuals (i.e., HIV-negative) evaluated for AVT, median age was 31 years, 24.6% were HBeAg-positive, and 27.9% had HBV DNA >2,000 IU/ml. AVT-eligibility was 17.0% by EASL, 10.2% by WHO, and 31.1% by Treat-B. Men had increased odds of eligibility. WHO (area under the receiver operating curve [AUROC], 0.68) and Treat-B criteria (AUROC, 0.76) had modest accuracy. Fourteen percent of HBsAg-positive individuals were HIV coinfection, and most coinfected individuals were taking tenofovir-containing antiretroviral therapy (ART). CONCLUSION: Approximately 1 in 6 HBV monoinfected adults in the general population in Zambia may be AVT-eligible. Men should be a major focus of hepatitis B diagnosis and treatment. Further development and evaluation of HBV treatment criteria for resource-limited settings is needed. In settings with overlapping HIV and HBV epidemics, scale-up of ART has contributed towards hepatitis B elimination.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/tratamiento farmacológico , Adulto , ADN Viral/sangre , Femenino , Infecciones por VIH/tratamiento farmacológico , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Hepatitis B Crónica/epidemiología , Humanos , Masculino , Selección de Paciente , Encuestas y Cuestionarios , Zambia/epidemiología
8.
World J Gastroenterol ; 25(31): 4512-4533, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31496629

RESUMEN

BACKGROUND: Esophageal cancer (EC) is associated with a poor prognosis, particularly so in Africa where an alarmingly high mortality to incidence ratio prevails for this disease. AIM: To provide further understanding of EC in the context of the unique cultural and genetic diversity, and socio-economic challenges faced on the African continent. METHODS: We performed a systematic review of studies from Africa to obtain data on epidemiology, risk factors, management and outcomes of EC. A non-systematic review was used to obtain incidence data from the International Agency for Research on Cancer, and the Cancer in Sub-Saharan reports. We searched EMBASE, PubMed, Web of Science, and Cochrane Central from inception to March 2019 and reviewed the list of articles retrieved. Random effects meta-analyses were used to assess heterogeneity between studies and to obtain odds ratio (OR) of the associations between EC and risk factors; and incidence rate ratios for EC between sexes with their respective 95% confidence intervals (CI). RESULTS: The incidence of EC is higher in males than females, except in North Africa where it is similar for both sexes. The highest age-standardized rate is from Malawi (30.3 and 19.4 cases/year/100000 population for males and females, respectively) followed by Kenya (28.7 cases/year/100000 population for both sexes). The incidence of EC rises sharply after the age of 40 years and reaches a peak at 75 years old. Meta-analysis shows a strong association with tobacco (OR 3.15, 95%CI: 2.83-3.50). There was significant heterogeneity between studies on alcohol consumption (OR 2.28, 95%CI: 1.94-2.65) and on low socioeconomic status (OR 139, 95%CI: 1.25-1.54) as risk factors, but these could also contribute to increasing the incidence of EC. The best treatment outcomes were with esophagectomy with survival rates of 76.6% at 3 years, and chemo-radiotherapy with an overall combined survival time of 267.50 d. CONCLUSION: Africa has high incidence and mortality rates of EC, with preventable and non-modifiable risk factors. Men in this setting are at increased risk due to their higher prevalence of tobacco and alcohol consumption. Management requires a multidisciplinary approach, and survival is significantly improved in the setting of esophagectomy and chemoradiation therapy.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Neoplasias Esofágicas/epidemiología , Fumar Tabaco/epidemiología , Adulto , África , Factores de Edad , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Quimioradioterapia Adyuvante , Neoplasias Esofágicas/etiología , Neoplasias Esofágicas/terapia , Esofagectomía , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Factores de Riesgo , Factores Sexuales , Factores Socioeconómicos , Tasa de Supervivencia , Fumar Tabaco/efectos adversos , Resultado del Tratamiento
9.
World J Hepatol ; 10(9): 622-628, 2018 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-30310540

RESUMEN

AIM: To characterize antiviral therapy eligibility among hepatitis B virus (HBV)-infected adults at a university hospital in Zambia. METHODS: Hepatitis B surface antigen-positive adults (n = 160) who were HIV-negative and referred to the hospital after a routine or clinically-driven HBV test were enrolled. Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), platelet count, hepatitis B e-antigen, and HBV DNA were measured. Liver fibrosis/cirrhosis was assessed by physical examination, AST-to-platelet ratio index, and transient elastography. In antiviral therapy-naïve individuals, we described HBV stages and antiviral therapy eligibility per World Health Organization (WHO) and by HBV test (routine vs clinical). Elevated ALT was > 19 in women and > 30 U/L in men. Among treatment-experienced individuals, we described medication side effects, adherence, and viral suppression. RESULTS: The median age was 33 years, 71.9% were men, and 30.9% were diagnosed with HBV through a clinically-driven test with the remainder identified via routine testing (at the blood bank, community events, etc.). Among 120 treatment-naïve individuals, 2.5% were categorized as immune tolerant, 11.7% were immune active, 35.6% were inactive carriers, and 46.7% had an indeterminate phenotype. Per WHO guidelines, 13 (10.8%) were eligible for immediate antiviral therapy. The odds of eligibility were eight times higher for those diagnosed at clinical vs routine settings (adjusted odds ratio, 8.33; 95%CI: 2.26-29.41). Among 40 treatment-experienced HBV patients, virtually all took tenofovir, and a history of mild side effects was reported in 20%. Though reported adherence was good, 12 of 29 (41.4%) had HBV DNA > 20 IU/mL. CONCLUSION: Approximately one in ten HBV-monoinfected Zambians were eligible for antivirals. Many had indeterminate phenotype and needed clinical follow-up.

10.
Am J Trop Med Hyg ; 98(4): 1152-1158, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29436337

RESUMEN

Cirrhosis is the dominant cause of portal hypertension globally but may be overshadowed by hepatosplenic schistosomiasis (HSS) in the tropics. In Zambia, schistosomiasis seroprevalence can reach 88% in endemic areas. Bacterial translocation (BT) drives portal hypertension in cirrhosis contributing to mortality but remains unexplored in HSS. Rifaximin, a non-absorbable antibiotic may reduce BT. We aimed to explore the influence of rifaximin on BT, inflammation, and fibrosis in HSS. In this phase II open-label trial (ISRCTN67590499), 186 patients with HSS in Zambia were evaluated and 85 were randomized to standard care with or without rifaximin for 42 days. Changes in markers of inflammation, BT, and fibrosis were the primary outcomes. BT was measured using plasma 16S rRNA, lipopolysaccharide-binding protein, and lipopolysaccharide, whereas hyaluronan was used to measure fibrosis. Tumor necrosis factor receptor 1 (TNFR1) and soluble cluster of differentiation 14 (sCD14) assessed inflammation. 16S rRNA reduced from baseline (median 146 copies/µL, interquartile range [IQR] 9, 537) to day 42 in the rifaximin group (median 63 copies/µL, IQR 12, 196), P < 0.01. The rise in sCD14 was lower (P < 0.01) in the rifaximin group (median rise 122 ng/mL, IQR-184, 783) than in the non-rifaximin group (median rise 832 ng/mL, IQR 530, 967). TNFR1 decreased (P < 0.01) in the rifaximin group (median -39 ng/mL IQR-306, 563) but increased in the non-rifaximin group (median 166 ng/mL, IQR 3, 337). Other markers remained unaffected. Rifaximin led to a reduction of inflammatory markers and bacterial 16S rRNA which may implicate BT in the inflammation in HSS.


Asunto(s)
Antibacterianos/farmacología , Traslocación Bacteriana/efectos de los fármacos , Inflamación/sangre , Parasitosis Hepáticas/tratamiento farmacológico , Rifaximina/farmacología , Esquistosomiasis/tratamiento farmacológico , Enfermedades del Bazo/tratamiento farmacológico , Adulto , Biomarcadores/sangre , Femenino , Humanos , Receptores de Lipopolisacáridos/sangre , Parasitosis Hepáticas/sangre , Parasitosis Hepáticas/microbiología , Masculino , Persona de Mediana Edad , ARN Bacteriano/sangre , ARN Ribosómico 16S/sangre , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Rifaximina/uso terapéutico , Esquistosomiasis/sangre , Esquistosomiasis/microbiología , Enfermedades del Bazo/sangre , Enfermedades del Bazo/microbiología , Zambia
11.
Trans R Soc Trop Med Hyg ; 111(9): 425-432, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29378031

RESUMEN

Background: Hepatocellular malignancy in young adults is a prominent feature of hepatitis B virus (HBV) infection in southern Africa. Here we report a cross-sectional study of liver pathology correlated with biomarkers in adults with HBV infection in Zambia. Methods: We analysed liver biopsies from Zambian patients with persistent HBV infection. Results: We analysed 104 patients with HBV infection and evidence of liver disease. We obtained liver biopsies from 53 adults; of these, 12 (23%) were hepatitis B e antigen seropositive. The genotype was evenly distributed between A and E. One biopsy showed malignancy. Stage was 3 or more in 11 of 52 (21%) biopsies free of malignancy and lobular inflammation was found in 50 (94%). Neither alanine aminotransferase (ALT) nor the γ-glutamyl transferase:platelet ratio (GPR) were correlated with the stage of disease but were correlated with total Ishak score (ρ=0.47, p=0.0004 and ρ=0.33, p=0.02, respectively). Large cell change was observed in 10 of 11 biopsies with fibrosis stage 3 or more and 16 of 41 with early disease (p=0.005). Serum α-fetoprotein was elevated, although still within the normal range, in patients with large cell change (median 3.6 [interquartile range {IQR} 1.6-5.1]) compared with those without (1.7 [IQR 1.0-2.8]; p=0.03). Neither ALT nor GPR predicted large cell change. Conclusions: Large cell change was common in young HBV-infected adults in Zambia. Only serum α-fetoprotein was identified as a biomarker of this phenotype.


Asunto(s)
Biomarcadores de Tumor/análisis , Hepatitis B/complicaciones , Neoplasias Hepáticas/diagnóstico , Adulto , Antígenos Bacterianos/análisis , Estudios Transversales , Femenino , Genotipo , Hepatitis B/sangre , Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Humanos , Neoplasias Hepáticas/etiología , Masculino , Adulto Joven , Zambia , alfa-Fetoproteínas/análisis
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