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Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease globally and is estimated to affect approximately 25% of the world's population. Data about the prevalence and incidence of NAFLD in Africa are scarce, but the prevalence is estimated to be 13·5% for the general population. This is likely to be an underestimate considering the increasing burden of non-communicable diseases, particularly the rising prevalence of obesity and type 2 diabetes, driven by the overlapping challenges of food insecurity, nutritional transition, and associated increased consumption of calorie-dense foods. Establishing the true prevalence of NAFLD, raising public awareness around the risk factors behind the increase in NAFLD, and proactively addressing all components of metabolic syndrome will be important to combat this silent epidemic, which will have long-term health-care costs and economic consequences for the region.

The interplay between hereditary and environmental factors in the causation of colorectal cancer in sub-Saharan Africa is poorly understood. We carried out a community based case-control study to identify the risk factors associated with colorectal cancer in Zimbabwe. We recruited 101 cases of colorectal cancer and 202 controls, matched for age, sex and domicile. Potential risk factors including family history, socioeconomic status, urbanization, diabetes mellitus and previous schistosomiasis were evaluated. Conditional logistic regression was used to estimate the odds ratios associated with the different factors. Cases were more likely to have a tertiary education (32.7 vs. 13.4%, P

Highlights • Three main dietary patterns in Zimbabwe; traditional African, urban and processed foods. • Traditional African diet associated with a reduced risk of colorectal cancer. • No association between colorectal cancer and the urban or processed food patterns., Background The rising incidence of colorectal cancer in sub-Saharan Africa may be partly caused by changing dietary patterns. We sought to establish the association between dietary patterns and colorectal cancer in Zimbabwe. Methods One hundred colorectal cancer cases and 200 community-based controls were recruited. Data were collected using a food frequency questionnaire, and dietary patterns derived by principal component analysis. Generalised linear and logistic regression models were used to assess the associations between dietary patterns, participant characteristics and colorectal cancer. Results Three main dietary patterns were identified: traditional African, urbanised and processed food. The traditional African diet appeared protective against colorectal cancer (Odds Ratio (OR) 0.35; 95% Confidence Interval (CI), 0.21 – 0.58), which had no association with the urban (OR 0.68; 95% CI, 0.43–1.08), or processed food (OR 0.91; 0.58–1.41) patterns. The traditional African diet was associated with rural domicile, (OR 1.26; 95% CI, 1.00–1.59), and a low income (OR1.48; 95% CI, 1.06–2.08). The urbanised diet was associated with urban domicile (OR 1.70; 95% CI, 1.38–2.10), secondary (OR 1.30; 95% CI, 1.07–1.59) or tertiary education (OR 1.48; 95% CI, 1.11–1.97), and monthly incomes of $201–500 (OR 1.30; 95% CI, 1.05–1.62), and the processed food pattern with tertiary education (OR 1.42; 95% CI, 1.05–1.92), and income >$1000/month (OR 1.48; 95% CI, 1.02–2.15). Conclusion A shift away from protective, traditional African dietary patterns may partly explain the rising incidence of colorectal cancer in sub-Saharan Africa.

Summary The perception that colorectal cancer is rare in sub-Saharan Africa is widely held; however, it is unclear whether this is due to poor epidemiological data or to lower disease rates. The quality of epidemiological data has somewhat improved, and there is an ongoing transition to western dietary and lifestyle practices associated with colorectal cancer. The impact of these changes on the incidence of colorectal cancer is not as evident as it is with other non-communicable diseases such as diabetes. In this Viewpoint, we discuss the epidemiology of colorectal cancer in sub-Saharan Africa. Colorectal cancer in this region frequently occurs at an early age, often with distinctive histological characteristics. We detail the crucial need for hypothesis-driven research on the risk factors for colorectal cancer in this population and identify key research gaps. Should colorectal cancer occur more frequently than assumed, then commensurate allocation of resources will be needed for diagnosis and treatment.

The incidence of colorectal cancer (CRC) is gradually rising in sub-Saharan Africa. This may be due to dietary changes associated with urbanization, which may induce tumor-promoting gut microbiota composition and function. We compared fecal microbiota composition and activity in 10 rural and 10 urban Zimbabweans for evidence of a differential CRC risk. Dietary intake was assessed by a food frequency questionnaire. Fecal microbiota composition, metabolomic profile, functional microbial genes were analyzed, and bile acids and short chain fatty acids quantified. Animal protein intake was higher among urban volunteers, but carbohydrate and fiber intake were similar. Bacteria related to Blautia obeum, Streptococcus bovis, and Subdoligranulum variabile were higher in urban residents, whereas bacteria related to Oscillospira guillermondii and Sporobacter termitidis were higher in rural volunteers. Fecal levels of primary bile acids, cholic acid, and chenodeoxycholic acid (P

BackgroundApproximately 25% of colorectal cancer patients in sub-Saharan Africa are younger than 40 years, and hereditary factors may contribute. We investigated the frequency and patterns of inherited colorectal cancer among black Zimbabweans.MethodsA population-based cross-sectional study of ninety individuals with a new diagnosis of colorectal cancer was carried out in Harare, Zimbabwe between November 2012 and December 2015. Phenotypic data was obtained using interviewer administered questionnaires, and reviewing clinical and pathology data. Cases were screened for mismatch repair deficiency by immunohistochemistry and/or microsatellite instability testing, and for MLH1, MSH2 and EPCAM deletions using multiplex ligation-dependent probe amplification. Next generation sequencing using a 16-gene panel was performed for cases with phenotypic features consistent with familial colorectal cancer. Variants were assessed for pathogenicity using the mean allele frequency, phenotypic features and searching online databases.ResultsThree Lynch syndrome cases were identified: MSH2 c.2634G>A pathogenic mutation, c.(1896+1_1897-1)_(*193_?)del , and one fulfilling the Amsterdam criteria, with MLH1 and PMS2 deficiency, but no identifiable pathogenic mutation. Two other cases had a strong family history of cancers, but the exact syndrome was not identified. The prevalence of Lynch syndrome was 3·3% (95% CI 0·7-9·4), and that of familial colorectal cancer was 5·6% (95% CI, 1·8-12·5).ConclusionsIdentifying cases of inherited colorectal cancer in sub-Saharan Africa is feasible, and our findings can inform screening guidelines appropriate to this setting.

Background Data on colorectal cancer (CRC) in sub-Saharan Africa is mainly based on hospital series which suggest low incidence and frequent early onset cancers. This study characterises colorectal cancer in a population-based cancer registry in Zimbabwe. Methods Cases of CRC recorded by the Zimbabwe National Cancer Registry between 2003 and 2012 were analysed. Demographic and pathological characteristics were compared according to ethnicity and age. Trends in age standardised incidence rates (ASR) were determined. Results There were 886 and 216 cases of CRC among black Africans and Caucasians respectively, and 26% of the black Africans were younger than 40 years. Signet ring cell carcinomas were more common among black Africans compared to Caucasians (4% vs 1%, p = 0.027). ASR increased by 1.9%/year and 3.9%/year among black African males and females respectively. Conclusion CRC incidence is rising among black Africans and has unique demographic and pathological characteristics.

Southern Africa continues to shoulder a disproportionate burden of the HIV epidemic with the number of new infections outstripping treatment initiation two- to threefold. Current prevention strategies have had a limited impact on the trajectory of the epidemic so far. The history of HIV prevention research is dominated by failed approaches, but recent developments have provided reason for hope. These include the successful male circumcision outcomes in trials in South Africa, Kenya and Uganda, the recent protective outcome of a tenofovir vaginal gel trial in South Africa and the proof that pre-exposure prophylaxis with oral combination tenofovir/emtricitabine can work in men. The latter positive outcome has however been shattered by the early closure of FEM-PrEP for futility. The challenge now is on how to best integrate emerging prevention methods with established strategies, recognising that some of the older methods have never been scaled up to saturation level.

AIM: To compare differences in the frequency of colorectal cancer at colonoscopy in Zimbabwe according to ethnicity. METHODS: All lower gastrointestinal endoscopic procedures performed between January 2006 and December 2011 at a gastroenterology clinic in Harare, Zimbabwe were reviewed. The demographic characteristics, clinical indications, differences in bowel preparation and the endoscopic and histological diagnoses were compared between different ethnic groups with emphasis on colorectal cancer. The clinical and demographic characteristics and the endoscopic findings were compared using the student t-test and the χ2 test, while the clinical indications associated with a diagnosis of colorectal cancer were determined by logistic regression. RESULTS: All colonoscopies and sigmoidoscopies performed in 1236 Caucasians, 460 black Africans and 109 Asians were analysed. Colorectal cancer was diagnosed more frequently in the black African patients compared to Caucasians or Asians (10% vs 3%, 10% vs 2%, P < 0.001). However, polyps were less common among black Africans (5%) compared to both Caucasians (8%) and Asians (9%) (P = 0.03). Among patients with colorectal cancer, black Africans tended to be younger than Caucasians, who were over-represented in the oldest age category; 32 % vs 2% were less than 50 years and 41% vs 78% were older than 60 years (P < 0.001). Anaemia and weight loss were associated with colorectal cancer in both black African [odds ratio (OR): 2.73 (95%CI: 1.33-5.61) and 3.09 (1.35-7.07)] and Caucasian patients [OR: 6.65 (95%CI: 2.93-15.09) and 3.47 (1.52-7.94)]. CONCLUSION: The likelihood of diagnosing colorectal cancer in patients referred for colonoscopy in Zimbabwe is at least as likely among black Africans as it is among Caucasians.

A pneumomediastinum is an unusual complication of respiratory infections in HIV-positive patients, usually reported in association with pneumocystis pneumonia. We describe a case of an HIV-positive patient with a pneumomediastinum who had cytomegalovirus pneumonitis. This is an important reminder to clinicians, since cytomegalovirus pneumonitis and pneumocystis pneumonia have a similar clinical and radiological presentation.

Idiopathic hypoparathyroidism is an uncommon medical condition, which may present with dementia. This may be misdiagnosed as 'senile dementia' in elderly patients. We report such a case, made more remarkable by associated extensive cerebral calcification and we review the background literature.