Characterizing prostate cancer risk through multi-ancestry genome-wide discovery of 187 novel risk variants

The transferability and clinical value of genetic risk scores (GRSs) across populations remain limited due to an imbalance in genetic studies across ancestrally diverse populations. Here we conducted a multi-ancestry genome-wide association study of 156,319 prostate cancer cases and 788,443 controls of European, African, Asian and Hispanic men, reflecting a 57% increase in the number of non-European cases over previous prostate cancer genome-wide association studies. We identified 187 novel risk variants for prostate cancer, increasing the total number of risk variants to 451. An externally replicated multi-ancestry GRS was associated with risk that ranged from 1.8 (per standard deviation) in African ancestry men to 2.2 in European ancestry men. The GRS was associated with a greater risk of aggressive versus non-aggressive disease in men of African ancestry (P = 0.03). Our study presents novel prostate cancer susceptibility loci and a GRS with effective risk stratification across ancestry groups.

Evaluating approaches for constructing polygenic risk scores for prostate cancer in men of African and European ancestry

Genome-wide polygenic risk scores (GW-PRSs) have been reported to have better predictive ability than PRSs based on genome-wide significance thresholds across numerous traits. We compared the predictive ability of several GW-PRS approaches to a recently developed PRS of 269 established prostate cancer-risk variants from multi-ancestry GWASs and fine-mapping studies (PRS269). GW-PRS models were trained with a large and diverse prostate cancer GWAS of 107,247 cases and 127,006 controls that we previously used to develop the multi-ancestry PRS269. Resulting models were independently tested in 1,586 cases and 1,047 controls of African ancestry from the California Uganda Study and 8,046 cases and 191,825 controls of European ancestry from the UK Biobank and further validated in 13,643 cases and 210,214 controls of European ancestry and 6,353 cases and 53,362 controls of African ancestry from the Million Veteran Program. In the testing data, the best performing GW-PRS approach had AUCs of 0.656 (95% CI = 0.635-0.677) in African and 0.844 (95% CI = 0.840-0.848) in European ancestry men and corresponding prostate cancer ORs of 1.83 (95% CI = 1.67-2.00) and 2.19 (95% CI = 2.14-2.25), respectively, for each SD unit increase in the GW-PRS. Compared to the GW-PRS, in African and European ancestry men, the PRS269 had larger or similar AUCs (AUC = 0.679, 95% CI = 0.659-0.700 and AUC = 0.845, 95% CI = 0.841-0.849, respectively) and comparable prostate cancer ORs (OR = 2.05, 95% CI = 1.87-2.26 and OR = 2.21, 95% CI = 2.16-2.26, respectively). Findings were similar in the validation studies. This investigation suggests that current GW-PRS approaches may not improve the ability to predict prostate cancer risk compared to the PRS269 developed from multi-ancestry GWASs and fine-mapping.

Evidence of Novel Susceptibility Variants for Prostate Cancer and a Multiancestry Polygenic Risk Score Associated with Aggressive Disease in Men of African Ancestry

BACKGROUND

Genetic factors play an important role in prostate cancer (PCa) susceptibility.

OBJECTIVE

To discover common genetic variants contributing to the risk of PCa in men of African ancestry.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a meta-analysis of ten genome-wide association studies consisting of 19378 cases and 61620 controls of African ancestry.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Common genotyped and imputed variants were tested for their association with PCa risk. Novel susceptibility loci were identified and incorporated into a multiancestry polygenic risk score (PRS). The PRS was evaluated for associations with PCa risk and disease aggressiveness.

RESULTS AND LIMITATIONS

Nine novel susceptibility loci for PCa were identified, of which seven were only found or substantially more common in men of African ancestry, including an African-specific stop-gain variant in the prostate-specific gene anoctamin 7 (ANO7). A multiancestry PRS of 278 risk variants conferred strong associations with PCa risk in African ancestry studies (odds ratios [ORs] >3 and >5 for men in the top PRS decile and percentile, respectively). More importantly, compared with men in the 40-60% PRS category, men in the top PRS decile had a significantly higher risk of aggressive PCa (OR = 1.23, 95% confidence interval = 1.10-1.38, p = 4.4 × 10-4).

CONCLUSIONS

This study demonstrates the importance of large-scale genetic studies in men of African ancestry for a better understanding of PCa susceptibility in this high-risk population and suggests a potential clinical utility of PRS in differentiating between the risks of developing aggressive and nonaggressive disease in men of African ancestry.

PATIENT SUMMARY

In this large genetic study in men of African ancestry, we discovered nine novel prostate cancer (PCa) risk variants. We also showed that a multiancestry polygenic risk score was effective in stratifying PCa risk, and was able to differentiate risk of aggressive and nonaggressive disease.

Evaluating Approaches for Constructing Polygenic Risk Scores for Prostate Cancer in Men of African and European Ancestry

Genome-wide polygenic risk scores (GW-PRS) have been reported to have better predictive ability than PRS based on genome-wide significance thresholds across numerous traits. We compared the predictive ability of several GW-PRS approaches to a recently developed PRS of 269 established prostate cancer risk variants from multi-ancestry GWAS and fine-mapping studies (PRS 269 ). GW-PRS models were trained using a large and diverse prostate cancer GWAS of 107,247 cases and 127,006 controls used to develop the multi-ancestry PRS 269 . Resulting models were independently tested in 1,586 cases and 1,047 controls of African ancestry from the California/Uganda Study and 8,046 cases and 191,825 controls of European ancestry from the UK Biobank and further validated in 13,643 cases and 210,214 controls of European ancestry and 6,353 cases and 53,362 controls of African ancestry from the Million Veteran Program. In the testing data, the best performing GW-PRS approach had AUCs of 0.656 (95% CI=0.635-0.677) in African and 0.844 (95% CI=0.840-0.848) in European ancestry men and corresponding prostate cancer OR of 1.83 (95% CI=1.67-2.00) and 2.19 (95% CI=2.14-2.25), respectively, for each SD unit increase in the GW-PRS. However, compared to the GW-PRS, in African and European ancestry men, the PRS 269 had larger or similar AUCs (AUC=0.679, 95% CI=0.659-0.700 and AUC=0.845, 95% CI=0.841-0.849, respectively) and comparable prostate cancer OR (OR=2.05, 95% CI=1.87-2.26 and OR=2.21, 95% CI=2.16-2.26, respectively). Findings were similar in the validation data. This investigation suggests that current GW-PRS approaches may not improve the ability to predict prostate cancer risk compared to the multi-ancestry PRS 269 constructed with fine-mapping.

Influence of thermoregulatory (Na & F) genes on performance and blood parameters of F2 and F3 generations of crosses of local and commercial chickens

High ambient temperatures pose serious productive challenges to poultry farmers in the tropics with adverse consequences such as reduced egg production. A study was undertaken to assess the effect of naked neck (Na) and frizzle (F) genes on the performance of F₂ and F₃ generations of crosses of commercial and indigenous chickens in Ghana. One thousand, five hundred and sixty-five (1,565) eggs distributed in a randomized complete block design comprising 4 genotypes and 15 hatches were used for the first study. The eggs were produced from 33 each F₂ crossbred normal-feathered (nanaff), naked neck (Na), frizzle (F) and both (Na and F) alleles carrying chickens to determine the effects of these genes on fertility and hatchability. Data were analysed using the mixed model procedure of GenStat statistical software. Eggs from birds with the heat-tolerant genes, either in the single or double doses, were significantly more fertile than those from birds without the genes. Eggs of birds carrying the F allele had significantly (P < 0.05) higher hatchability than eggs from birds carrying the Na allele.Subsequently, 199 F₃ crossbred chickens obtained from six hatches generated by the F₂ generation were used for the evaluation of growth, egg production, haematological and blood biochemical parameters. The genotypic groups were normal feathered (nanaff), homozygous naked neck (NaNaff), heterozygous naked neck (Nanaff), homozygous frizzle (nanaFF), heterozygous frizzle (nanaFf), double homozygous naked neck-frizzle (NaNaFF) and double heterozygous naked neck- frizzle (NanaFf). The Nanaff recorded a significantly (P < 0.05) heavier day-old body weight compared to all other genotypes except the NaNaff birds.The nanaff genotype reached sexual maturity significantly earlier than all other genotypes. Hen day egg production and egg weight were also significantly higher in nanaff birds compared to birds carrying either Na or F allele, or both alleles. All birds carrying the naked neck and frizzle genes had significantly higher packed cell volume (PCV) concentration than the nanaff genotype. The Nanaff genotype recorded a significantly higher blood haemoglobin concentration compared to the nanaff, nanaFf and NaNaFF ones. However, birds carrying the thermoregulatory genes recorded significantly (P < 0.05) higher haemoglobin values except for the heterozygous frizzle. The thermoregulatory genes are of importance in chicken populations in Ghana as they positively influence percentage fertility of chicken eggs and PCV concentrations of chicken blood.

A Rare Germline HOXB13 Variant Contributes to Risk of Prostate Cancer in Men of African Ancestry

A rare African ancestry-specific germline deletion variant in HOXB13 (X285K, rs77179853) was recently reported in Martinican men with early-onset prostate cancer. Given the role of HOXB13 germline variation in prostate cancer, we investigated the association between HOXB13 X285K and prostate cancer risk in a large sample of 22 361 African ancestry men, including 11 688 prostate cancer cases. The risk allele was present only in men of West African ancestry, with an allele frequency in men that ranged from 0.40% in Ghana and 0.31% in Nigeria to 0% in Uganda and South Africa, with a range of frequencies in men with admixed African ancestry from North America and Europe (0-0.26%). HOXB13 X285K was associated with 2.4-fold increased odds of prostate cancer (95% confidence interval [CI] = 1.5-3.9, p = 2 × 10^-4), with greater risk observed for more aggressive and advanced disease (Gleason ≥8: odds ratio [OR] = 4.7, 95% CI = 2.3-9.5, p = 2 × 10^-5; stage T3/T4: OR = 4.5, 95% CI = 2.0-10.0, p = 2 × 10^-4; metastatic disease: OR = 5.1, 95% CI = 1.9-13.7, p = 0.001). We estimated that the allele arose in West Africa 1500-4600 yr ago. Further analysis is needed to understand how the HOXB13 X285K variant impacts the HOXB13 protein and function in the prostate. Understanding who carries this mutation may inform prostate cancer screening in men of West African ancestry. PATIENT SUMMARY: A rare African ancestry-specific germline deletion in HOXB13, found only in men of West African ancestry, was reported to be associated with an increased risk of overall and advanced prostate cancer. Understanding who carries this mutation may help inform screening for prostate cancer in men of West African ancestry.

Abstract PO-199: Determining the association between circulating fatty acids, immune oncological markers, and prostate cancer risk in a diverse cohort

Men of African descent, including African American (AA) men and Ghanaian (AFR) men, have a disproportionately higher burden of lethal prostate cancer (PCa) when compared to European American (EA) men. This increased mortality burden could be partially attributed to lifestyle factors including the intake of dietary fatty acids and their metabolism, but may also relate to differences in inflammation and immune function. Although the extent to which fatty acids are PCa risk factors remains controversial, the relationship between fatty acids, inflammation and immune function, and PCa in men of African descent remains largely unexplored. Therefore, the goal of our study was to characterize the relationship between circulating fatty acids, immune-oncological mediators, and PCa in the ethnically diverse NCI-Maryland and NCI-Ghana Prostate Cancer Case-Control studies, with an over-representation of men of African descent. A CLIA-certified, mass spectrometry-based assay was applied to measure 24 fatty acids in sera from 1,562 cases and 1,693 controls. Logistic regression analyses were performed on seven types of fatty acids including total, saturated, trans, cis-monounsaturated, omega-6, omega-3 fatty acids, and the omega 6:3 fatty acid ratio to explore disease associations by population group. Additionally, we measured 82 immune-oncological proteins in the same sera and explored their role as potential mediators of the relationship between fatty acids and PCa. Using this approach, we observed a significant association between trans fatty acid levels and the odds of developing PCa in all three racial/ethnic groups. Although AFR men were found to have the lowest level of trans fatty acids compared to AA and EA men, they still experienced significantly increased odds of developing PCa with increasing trans fatty acid levels. Exploratory mediation analyses found a relationship between Palmitelaidic trans fatty acid levels and two circulating proteins, CD27 and CXCL1, with protein levels being higher in men with elevated levels of circulating Palmitelaidic trans fatty acids and an increased risk of PCa. Our findings point to a previously unexplored oncogenic role of fatty acids and immune-oncological mediators in men of African descent with PCa.

Citation Format: Brittany D. Lord, Tsion Minas, Tiffany H. Dorsey, Francine Baker, Wei Tang, Edward D. Yeboah, Yao Tettey, Richard B. Biritwum, Andrew A. Adjei, Evelyn Tay, James E. Mensah, Robert N. Hoover, Ann W. Hsing, Michael B. Cook, Stefan Ambs. Determining the association between circulating fatty acids, immune oncological markers, and prostate cancer risk in a diverse cohort [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-199.

Putative pathogen-selected polymorphisms in the PKLR gene are associated with mycobacterial susceptibility in Brazilian and African populations

Pyruvate kinase (PK), encoded by the PKLR gene, is a key player in glycolysis controlling the integrity of erythrocytes. Due to Plasmodium selection, mutations for PK deficiency, which leads to hemolytic anemia, are associated with resistance to malaria in sub-Saharan Africa and with susceptibility to intracellular pathogens in experimental models. In this case-control study, we enrolled 4,555 individuals and investigated whether PKLR single nucleotide polymorphisms (SNPs) putatively selected for malaria resistance are associated with susceptibility to leprosy across Brazil (Manaus-North; Salvador-Northeast; Rondonópolis-Midwest and Rio de Janeiro-Southeast) and with tuberculosis in Mozambique. Haplotype T/G/G (rs1052176/rs4971072/rs11264359) was associated with leprosy susceptibility in Rio de Janeiro (OR = 2.46, p = 0.00001) and Salvador (OR = 1.57, p = 0.04), and with tuberculosis in Mozambique (OR = 1.52, p = 0.07). This haplotype downregulates PKLR expression in nerve and skin, accordingly to GTEx, and might subtly modulate ferritin and haptoglobin levels in serum. Furthermore, we observed genetic signatures of positive selection in the HCN3 gene (xpEHH>2 -recent selection) in Europe but not in Africa, involving 6 SNPs which are PKLR/HCN3 eQTLs. However, this evidence was not corroborated by the other tests (FST, Tajima's D and iHS). Altogether, we provide evidence that a common PKLR locus in Africans contribute to mycobacterial susceptibility in African descent populations and also highlight, for first, PKLR as a susceptibility gene for leprosy and TB.

Trans-ancestry genome-wide association meta-analysis of prostate cancer identifies new susceptibility loci and informs genetic risk prediction

Prostate cancer is a highly heritable disease with large disparities in incidence rates across ancestry populations. We conducted a multiancestry meta-analysis of prostate cancer genome-wide association studies (107,247 cases and 127,006 controls) and identified 86 new genetic risk variants independently associated with prostate cancer risk, bringing the total to 269 known risk variants. The top genetic risk score (GRS) decile was associated with odds ratios that ranged from 5.06 (95% confidence interval (CI), 4.84-5.29) for men of European ancestry to 3.74 (95% CI, 3.36-4.17) for men of African ancestry. Men of African ancestry were estimated to have a mean GRS that was 2.18-times higher (95% CI, 2.14-2.22), and men of East Asian ancestry 0.73-times lower (95% CI, 0.71-0.76), than men of European ancestry. These findings support the role of germline variation contributing to population differences in prostate cancer risk, with the GRS offering an approach for personalized risk prediction.

Overall and abdominal obesity and prostate cancer risk in a West African population: An analysis of the Ghana Prostate Study

Obesity has been associated with an increased risk of advanced prostate cancer. However, most studies have been conducted among North American and European populations. Prostate cancer mortality appears elevated in West Africa, yet risk factors for prostate cancer in this region are unknown. We thus examined the relationship between obesity and prostate cancer using a case-control study conducted in Accra, Ghana in 2004 to 2012. Cases and controls were drawn from a population-based sample of 1037 men screened for prostate cancer, yielding 73 cases and 964 controls. An additional 493 incident cases were recruited from the Korle-Bu Teaching Hospital. Anthropometric measurements were taken at enrollment. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR) and prostate cancer, adjusting for potential confounders. The mean BMI was 25.1 kg/m² for cases and 24.3 kg/m² for controls. After adjustment, men with BMI ≥ 30 kg/m² had an increased risk of prostate cancer relative to men with BMI < 25 kg/m² (OR 1.86, 95% CI 1.11-3.13). Elevated WC (OR 1.76, 95% CI 1.24-2.51) and WHR (OR 1.46, 95% CI 0.99-2.16) were also associated with prostate cancer. Associations were not modified by smoking status and were evident for low- and high-grade disease. These findings indicate that overall and abdominal obesity are positively associated with prostate cancer among men in Ghana, implicating obesity as a potentially modifiable risk factor for prostate cancer in this region.

Genetic signatures of gene flow and malaria-driven natural selection in sub-Saharan populations of the "endemic Burkitt Lymphoma belt"

Populations in sub-Saharan Africa have historically been exposed to intense selection from chronic infection with falciparum malaria. Interestingly, populations with the highest malaria intensity can be identified by the increased occurrence of endemic Burkitt Lymphoma (eBL), a pediatric cancer that affects populations with intense malaria exposure, in the so called "eBL belt" in sub-Saharan Africa. However, the effects of intense malaria exposure and sub-Saharan populations' genetic histories remain poorly explored. To determine if historical migrations and intense malaria exposure have shaped the genetic composition of the eBL belt populations, we genotyped ~4.3 million SNPs in 1,708 individuals from Ghana and Northern Uganda, located on opposite sides of eBL belt and with ≥ 7 months/year of intense malaria exposure and published evidence of high incidence of BL. Among 35 Ghanaian tribes, we showed a predominantly West-Central African ancestry and genomic footprints of gene flow from Gambian and East African populations. In Uganda, the North West population showed a predominantly Nilotic ancestry, and the North Central population was a mixture of Nilotic and Southern Bantu ancestry, while the Southwest Ugandan population showed a predominant Southern Bantu ancestry. Our results support the hypothesis of diverse ancestral origins of the Ugandan, Kenyan and Tanzanian Great Lakes African populations, reflecting a confluence of Nilotic, Cushitic and Bantu migrations in the last 3000 years. Natural selection analyses suggest, for the first time, a strong positive selection signal in the ATP2B4 gene (rs10900588) in Northern Ugandan populations. These findings provide important baseline genomic data to facilitate disease association studies, including of eBL, in eBL belt populations.

Usual adult occupation and risk of prostate cancer in West African men: the Ghana Prostate Study

OBJECTIVES

Established prostate cancer (PCa) risk factors include age, family history of PCa and African ancestry. Studies, mostly among highly screened, predominantly European ancestral populations, suggest that employment in certain occupations (eg, farming, military) may also have an increased risk for PCa. Here, we evaluated the association between usual adult occupation and PCa risk in Ghanaian men, a population with historically low rates of PCa screening.

METHODS

The Ghana Prostate Study is a case-control study of PCa that was conducted from 2004 to 2012 in 749 cases and 964 controls. In-person interviews were conducted to collect information from participants, including longest held job. Industrial hygienists classified job titles into occupational categories. Unconditional logistic regression was used to calculate ORs and 95% CIs for the association between longest held job and PCa risk (overall, aggressive (Gleason≥7)), controlling for potential confounders.

RESULTS

Risk was increased among men in management (overall PCa OR=2.2, 95% CI 1.4 to 3.2; aggressive PCa OR=2.2, 95% CI 1.3 to 3.5) and military occupations (overall PCa OR=3.4, 95% CI 1.7 to 7.0; aggressive PCa OR=3.5, 95% CI 1.5 to 8.3). Risks were also elevated for management and military-specific jobs based on 3-digit level Standard Occupational Classification definitions. Sensitivity analyses accounting for access to medical care did not show significant differences.

CONCLUSIONS

Our study provides some evidence for increased risk of PCa among men in management and military occupations, which is consistent with the published literature. Additional research is needed to clarify the drivers of the associations between these occupations and PCa.

TMPRSS2:ERG Gene Fusions in Prostate Cancer of West African Men and a Meta-Analysis of Racial Differences

The prevalence of fusions of the transmembrane protease, serine 2, gene (TMPRSS2) with the erythroblast transformation-specific-related gene (ERG), or TMPRSS2:ERG, in prostate cancer varies by race. However, such somatic aberration and its association with prognostic factors have neither been studied in a West African population nor been systematically reviewed in the context of racial differences. We used immunohistochemistry to assess oncoprotein encoded by the ERG gene as the established surrogate of ERG fusion genes among 262 prostate cancer biopsies from the Ghana Prostate Study (2004-2006). Poisson regression with robust variance estimation provided prevalence ratios and 95% confidence intervals of ERG expression in relation to patient characteristics. We found that 47 of 262 (18%) prostate cancers were ERG-positive, and being negative for ERG staining was associated with higher Gleason score. We further conducted a systematic review and meta-analysis of TMPRSS2:ERG fusions in relation to race, Gleason score, and tumor stage, combining results from Ghana with 40 additional studies. Meta-analysis showed the prevalence of TMPRSS2:ERG fusions in prostate cancer to be highest in men of European descent (49%), followed by men of Asian (27%) and then African (25%) descent. The lower prevalence of TMPRSS2:ERG fusions in men of African descent implies that alternative genomic mechanisms might explain the disproportionately high prostate cancer burden in such populations.

MANAGEMENT OF PROSTATE CANCER IN ACCRA, GHANA

INTRODUCTION

Africans living with prostate cancer in Africa face problems of early diagnosis and appropriate treatment.

AIM

To study the clinical incidence of prostate cancer, risk factors, TNM stage, their management and outcomes.

METHODS

A prospective study of Prostate Cancer cases managed at Korle Bu Teaching Hospital and hospitals in Accra, diagnosed by history, abnormal PSA/DRE, physical examination and histologically confirmed by biopsy from 2004 to 2013 was carried out. The cases were TNM staged and managed by approved protocol.

RESULTS

There were 669 cases with a mean age 70±0.045SE years, median Gleason Score of 7, organ confined Prostate Cancer(PC) in 415(62%), locally advanced in 167(25%) and metastatic Prostate Cancer in 87(13%) cases. The cases were followed for median of 10 months to ≥ 84 months. Organ confined cases were managed by: Radical Prostatectomy (RP) 92 (13.8%) with a mortality of 0.3%; brachytherapy 70 (10.5%) with a mortality of 0.1% and External Beam Radiotherapy (EBRT) 155 (23%) with a mortality 0.7%. In all, 98 men constituting (14.1%) cases with a mean age of 75+0.25SE years, life expectancy <10 years were treated by hormonal therapy with a mortality of 1.7%. Twenty cases who were for active surveillance (GS6), PSA <10ng/ml, life expectancy <10 years later all opted for EBRT. Locally advanced cases 25% all had neoadjuvant hormonal therapy then Brachytherapy in 3 (0.4%) mortality 0.15% and EBRT in 64 (9.5%), mortality 0.59%. Hormonal therapy was given in 100 (15%) locally advanced cases, mortality 5%. Metastatic prostate cancer cases (13%) were managed by hormonal therapy, mortality 6%.

CONCLUSION

Improved facilities and dedicated skilled teams led to a significant rise in proportion of organ confined Prostate Cancer from 15.3% to 62% curable by Radical Prostatectomy, brachytherapy or EBRT with longer disease free survival.

PREVALENCE OF BENIGN PROSTATIC HYPERPLASIA AND PROSTATE CANCER IN AFRICANS AND AFRICANS IN THE DIASPORA

BACKGROUND

There have been several publications on population or community prevalence of benign prostatic hyperplasia and prostate cancer from various countries and races but few reports are from Africa on Africans.

AIM

A review on the prevalence of benign prostatic hyperplasia and prostate cancer in Africans and other races.

METHODOLOGY

The current literature on prevalence of benign prostatic hyperplasia (BPH), prostate cancer (PC), and benign prostatic hyperplasia co-existing with prostate cancer in Africans and other races is reviewed.

RESULTS

Benign prostatic hyperplasia (BPH) prevalence in Ghana is responsible for 60% acute retention of urine and 28.6% of haematuria. Worldwide prevalence of BPH varies from 20 - 62% in men over 50 years and this includes USA, UK, Japan and Ghana. Reports from South Africa indicate prevalence of over 50% in adult males of 60 years. BPH co-existing with PC - Reports from USA, UK and Japan and Ghana reveal moderate association of BPH and PC. The co-existence of PC in patients being treated for BPH is 3 - 20% Prostate Cancer prevalence - There is high prevalence in USA, Scandinavian Countries, African Americans (AA) and Caribbean blacks. Ghana, Trinidad & Tobago have reported high prevalence of 6 -10% in men aged 50 years and above but others reported low prevalence in Africans from Africa. The low reporting from Africa of 10 - 40:100,000 is attributable to under reporting, absence of PSA screening/testing, lack of reliable cancer registries and poor medical facilities. Economic Costs of BPH and PC: BPH in the USA national direct costs are estimated at U$4Billion and individual costs of US$1536 annually. In Ghana, individual costs for BPH medications range from US$300 - 550 per year and cost for simple prostatectomy/TURP is estimated at US$1100. For prostate cancer, individual direct costs from Europe range from 6,575 - 12,000 euros, £2818.00 UK and over U$12,000 - 20,000 in USA per annum. In Ghana, individual direct costs ranges, for radical prostatectomy and external beam radiotherapy US$1250 - 1500, for brachytherapy 9,000 Euros, for hormonal therapy US$1600 - 3200) per year and US$510 for orchidectomy.

CONCLUSION

Recent evidence although sparse indicate there is high prevalence of BPH and PC in Africans and men of African descent in diaspora, the low prevalence of BPH and PC reported from some African countries is likely to under reporting and future prevalence studies both in the living and deceased are recommended to reveal the true prevalence of BPH and PC in Africans though screening for PC in the living remains controversial.

Abstract LB-371: ERG protein expression in diagnostic prostate cancer tissues among West African men

Background: Fusion of androgen regulated TMPRSS2 gene and the ERG oncogene is a common recurrent chromosomal aberration in prostate cancer, which leads to elevated expression of ERG oncoprotein. ERG expression detected by immunohistochemistry (IHC) has been validated as a proxy of TMPRSS2-ERG gene fusion. The prevalence of TMPRSS2-ERG gene fusion has been shown to vary by race being highest in Caucasian prostate cancer patients, followed by African American and then Asian. However, the prevalence of TMPRSS2-ERG gene fusion in African prostate cancer populations remains to be determined.

Methods and Materials: There were 428 prostate cancer patients diagnosed during 2004-2012 in the Ghana Prostate Study who had formalin-fixed paraffin-embedded needle biopsy tissues available for analysis. Pathologists centrally scored 262 tissue samples for ERG expression and Gleason patterns, after excluding 166 without sufficient tissues. ERG-positive nuclear immunostaining of normal endothelial cells was used as an internal control and only nuclear immunostaining of prostate cancer cells was deemed ERG-positive. We evaluated ERG expression status in relation to clinicopathological characteristics using logistic regression models. To assess potential selection bias, we performed sensitivity analyses comparing clinicopathological characteristics extracted from medical records by inclusion/exclusion status.

Results: We found 47 (18%) tissue samples were ERG-positive. Since recently preserved tissues appeared more likely to be ERG-negative (P = 0.044), all logistic regression models were adjusted for calendar year of diagnosis. Negative ERG staining was significantly associated with higher Gleason score (P = 0.035), in particular with higher primary Gleason grade (P = 0.028). Age at diagnosis, PSA concentration at diagnosis, and tribal group were not significantly associated with ERG expression status. Sensitivity analyses revealed that excluded tissues were more likely to be preserved in earlier years (P = 0.033) and to have lower Gleason scores (P = 0.003).

Conclusions: This first study of ERG expression in an African prostate cancer population indicates that the prevalence of TMPRSS2-ERG gene fusion is similar to that of African American patients but lower than those with European ancestry. Whether this lower proportion of TMPRSS2-ERG gene fusion leads to a greater proportion of aggressive prostate cancer in African men or is the result of diagnostic selection of a higher proportion of symptomatic, high Gleason score prostate cancers in such populations remains unknown.

Citation Format: Cindy Ke Zhou, Denise Young, Edward D. Yeboah, Richard B. Biritwum, Andrew A. Adjei, Yao Tettey, Evelyn Tay, Shelley Niwa, Ann L. Truelove, Isabell A. Sesterhenn, Shiv Srivastava, Robert N. Hoover, Ann W. Hsing, Michael B. Cook. ERG protein expression in diagnostic prostate cancer tissues among West African men. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-371.

Atlas of prostate cancer heritability in European and African-American men pinpoints tissue-specific regulation

Although genome-wide association studies have identified over 100 risk loci that explain ∼33% of familial risk for prostate cancer (PrCa), their functional effects on risk remain largely unknown. Here we use genotype data from 59,089 men of European and African American ancestries combined with cell-type-specific epigenetic data to build a genomic atlas of single-nucleotide polymorphism (SNP) heritability in PrCa. We find significant differences in heritability between variants in prostate-relevant epigenetic marks defined in normal versus tumour tissue as well as between tissue and cell lines. The majority of SNP heritability lies in regions marked by H3k27 acetylation in prostate adenoc7arcinoma cell line (LNCaP) or by DNaseI hypersensitive sites in cancer cell lines. We find a high degree of similarity between European and African American ancestries suggesting a similar genetic architecture from common variation underlying PrCa risk. Our findings showcase the power of integrating functional annotation with genetic data to understand the genetic basis of PrCa.

Determinants of peri-operative blood transfusion in a contemporary series of open prostatectomy for benign prostate hyperplasia

Background

The objective of this study was to determine the factors responsible for peri-operative blood transfusion in a contemporary series of open prostatectomy for benign prostate hyperplasia and thus offer a guide for blood product management for the procedure.

Methods

This was a prospective study of 200 consecutive patients who underwent open prostatectomy for BPH from January 2010 to September 2013 at the Korle Bu Teaching Hospital, Accra. The data analyzed included the pre-operative blood haemoglobin level (Hb), presence of co-morbidities, the case type, indication for the surgery, ASA score, anaesthetic method used, systolic blood pressure, status of the operating surgeon, duration of surgery and the operative prostate weight. The transfusion of blood peri-operatively was also documented.

Results

The mean age of the patients was 69.1 years. Elective cases formed 83.5 % with refractory retention of urine being the commonest indication for surgery (68.0 %). The mean pre-operative Hb was 12.1 g/dl. Consultants performed 56.0 % of the prostatectomies. Transvesical approach was used in 90.0 % of the cases. The mean operative time was 101.3mins (range 35.0–240.0) with a mean operative prostate weight of 110.8 g (range 15–550 g). Most of the patients (82.0 %) had spinal anaesthesia. The blood transfusion rate was 23.5 %. The transfusion rate was significantly higher in patients with anaemia (p = .000), emergency cases (p = .000), the use of general anaesthesia (p = .002), a resident as the operating surgeons (p = .034), prostate weight >100 g (p = .000) and duration of surgery (p = .011). In a multivariable logistic regression analysis however only the pre-operative Hb (p = .000. OR 0.95, 95 % CI [0.035–0.257]) and the duration of surgery (p = .025, OR 1.021, 95 % CI [1.003–1.039]) could predict blood transfusion in open prostatectomy for BPH in this series.

Conclusions

A ‘group and save’ policy should be the preferred blood ordering procedure for patients with Hb ≥ 13.0 g/dl scheduled for an elective open prostatectomy for BPH under spinal anaesthesia. A long operative time however may increase the need for blood transfusion.

Prostate Cancer Susceptibility in Men of African Ancestry at 8q24

The 8q24 region harbors multiple risk variants for distinct cancers, including >8 for prostate cancer. In this study, we conducted fine mapping of the 8q24 risk region (127.8-128.8Mb) in search of novel associations with common and rare variation in 4853 prostate cancer case patients and 4678 control subjects of African ancestry. All statistical tests were two-sided. We identified three independent associations at P values of less than 5.00×10(-8), all of which were replicated in studies from Ghana and Uganda (combined sample = 5869 case patients, 5615 control subjects; rs114798100: risk allele frequency [RAF] = 0.04, per-allele odds ratio [OR] = 2.31, 95% confidence interval [CI] = 2.04 to 2.61, P = 2.38×10(-40); rs72725879: RAF = 0.33, OR = 1.37, 95% CI = 1.30 to 1.45, P = 3.04×10(-27); and rs111906932: RAF = 0.03, OR = 1.79, 95% CI = 1.53 to 2.08, P = 1.39×10(-13)). Risk variants rs114798100 and rs111906923 are only found in men of African ancestry, with rs111906923 representing a novel association signal. The three variants are located within or near a number of prostate cancer-associated long noncoding RNAs (lncRNAs), including PRNCR1, PCAT1, and PCAT2. These findings highlight ancestry-specific risk variation and implicate prostate-specific lncRNAs at the 8q24 prostate cancer susceptibility region.

Integration of multiethnic fine-mapping and genomic annotation to prioritize candidate functional SNPs at prostate cancer susceptibility regions

Interpretation of biological mechanisms underlying genetic risk associations for prostate cancer is complicated by the relatively large number of risk variants (n = 100) and the thousands of surrogate SNPs in linkage disequilibrium. Here, we combined three distinct approaches: multiethnic fine-mapping, putative functional annotation (based upon epigenetic data and genome-encoded features), and expression quantitative trait loci (eQTL) analyses, in an attempt to reduce this complexity. We examined 67 risk regions using genotyping and imputation-based fine-mapping in populations of European (cases/controls: 8600/6946), African (cases/controls: 5327/5136), Japanese (cases/controls: 2563/4391) and Latino (cases/controls: 1034/1046) ancestry. Markers at 55 regions passed a region-specific significance threshold (P-value cutoff range: 3.9 × 10(-4)-5.6 × 10(-3)) and in 30 regions we identified markers that were more significantly associated with risk than the previously reported variants in the multiethnic sample. Novel secondary signals (P < 5.0 × 10(-6)) were also detected in two regions (rs13062436/3q21 and rs17181170/3p12). Among 666 variants in the 55 regions with P-values within one order of magnitude of the most-associated marker, 193 variants (29%) in 48 regions overlapped with epigenetic or other putative functional marks. In 11 of the 55 regions, cis-eQTLs were detected with nearby genes. For 12 of the 55 regions (22%), the most significant region-specific, prostate-cancer associated variant represented the strongest candidate functional variant based on our annotations; the number of regions increased to 20 (36%) and 27 (49%) when examining the 2 and 3 most significantly associated variants in each region, respectively. These results have prioritized subsets of candidate variants for downstream functional evaluation.

Imputation and subset-based association analysis across different cancer types identifies multiple independent risk loci in the TERT-CLPTM1L region on chromosome 5p15.33

Genome-wide association studies (GWAS) have mapped risk alleles for at least 10 distinct cancers to a small region of 63 000 bp on chromosome 5p15.33. This region harbors the TERT and CLPTM1L genes; the former encodes the catalytic subunit of telomerase reverse transcriptase and the latter may play a role in apoptosis. To investigate further the genetic architecture of common susceptibility alleles in this region, we conducted an agnostic subset-based meta-analysis (association analysis based on subsets) across six distinct cancers in 34 248 cases and 45 036 controls. Based on sequential conditional analysis, we identified as many as six independent risk loci marked by common single-nucleotide polymorphisms: five in the TERT gene (Region 1: rs7726159, P = 2.10 × 10(-39); Region 3: rs2853677, P = 3.30 × 10(-36) and PConditional = 2.36 × 10(-8); Region 4: rs2736098, P = 3.87 × 10(-12) and PConditional = 5.19 × 10(-6), Region 5: rs13172201, P = 0.041 and PConditional = 2.04 × 10(-6); and Region 6: rs10069690, P = 7.49 × 10(-15) and PConditional = 5.35 × 10(-7)) and one in the neighboring CLPTM1L gene (Region 2: rs451360; P = 1.90 × 10(-18) and PConditional = 7.06 × 10(-16)). Between three and five cancers mapped to each independent locus with both risk-enhancing and protective effects. Allele-specific effects on DNA methylation were seen for a subset of risk loci, indicating that methylation and subsequent effects on gene expression may contribute to the biology of risk variants on 5p15.33. Our results provide strong support for extensive pleiotropy across this region of 5p15.33, to an extent not previously observed in other cancer susceptibility loci.

A meta-analysis of 87,040 individuals identifies 23 new susceptibility loci for prostate cancer

Genome-wide association studies (GWAS) have identified 76 variants associated with prostate cancer risk predominantly in populations of European ancestry. To identify additional susceptibility loci for this common cancer, we conducted a meta-analysis of > 10 million SNPs in 43,303 prostate cancer cases and 43,737 controls from studies in populations of European, African, Japanese and Latino ancestry. Twenty-three new susceptibility loci were identified at association P < 5 × 10(-8); 15 variants were identified among men of European ancestry, 7 were identified in multi-ancestry analyses and 1 was associated with early-onset prostate cancer. These 23 variants, in combination with known prostate cancer risk variants, explain 33% of the familial risk for this disease in European-ancestry populations. These findings provide new regions for investigation into the pathogenesis of prostate cancer and demonstrate the usefulness of combining ancestrally diverse populations to discover risk loci for disease.

A genome-wide association study of prostate cancer in West African men

Age-adjusted mortality rates for prostate cancer are higher for African-American men compared with those of European ancestry. Recent data suggest that West African men also have elevated risk for prostate cancer relative to European men. Genetic susceptibility to prostate cancer could account for part of this difference. We conducted a genome-wide association study (GWAS) of prostate cancer in West African men in the Ghana Prostate Study. Association testing was performed using multivariable logistic regression adjusted for age and genetic ancestry for 474 prostate cancer cases and 458 population-based controls on the Illumina HumanOmni-5 Quad BeadChip. The most promising association was at 10p14 within an intron of a long non-coding RNA (lncRNA RP11-543F8.2) 360 kb centromeric of GATA3 (p = 1.29E-7). In sub-analyses, SNPs at 5q31.3 were associated with high Gleason score (≥7) cancers, the strongest of which was a missense SNP in PCDHA1 (rs34575154, p = 3.66E-8), and SNPs at Xq28 (rs985081, p = 8.66E-9) and 6q21 (rs2185710, p = 5.95E-8) were associated with low Gleason score (<7) cancers. We sought to validate our findings in silico in the African Ancestry Prostate Cancer GWAS Consortium, but only one SNP, at 10p14, replicated at p < 0.05. Of the 90 prostate cancer loci reported from studies of men of European, Asian or African-American ancestry, we were able to test 81 in the Ghana Prostate Study, and 10 of these replicated at p < 0.05. Further genetic studies of prostate cancer in West African men are needed to confirm our promising susceptibility loci.

Foreign body in scrotum following a boat engine blast accident

Male genital injuries, demand prompt management to prevent long-term sexual and psychological damage. Injuries to the scrotum and contents may produce impaired fertility.We report our experience in diagnosing and managing a case of a foreign body in the scrotum following a boat engine blast accident. This case report highlights the need for a good history and thorough general examination to establish the mechanism of injury in order to distinguish between an embedded penetrating projectile injury and an injury with an exit wound. Prompt surgical exploration with hematoma evacuation limits complications.

SURGICAL MANAGEMENT OF BPH IN GHANA: A NEED TO IMPROVE ACCESS TO TRANSURETHRAL RESECTION OF THE PROSTATE

BACKGROUND

Open prostatectomy for benign prostate hyperplasia (BPH) is widely practiced in Ghana and Africa. Some of the reasons include lack of expertise and facilities for Transurethral Resection of the Prostate (TURP) and digital rectal examination assessment of prostates as greater than 50 grams.

OBJECTIVES

To assess the prostate volumes of patients for surgical management of BPH by transrectal ultrasound (TRUS) and to determine, on the basis of prostatic volume, what percentage of those who had open prostatectomy could have been managed by TURP.

DESIGN

Prospective cohort study.

SETTING

The Korle Bu Teaching Hospital, Accra, Ghana.

SUBJECTS

Patients for elective surgical management of BPH from March to September 2010 were studied.

RESULTS

Fifty-eight. patients had surgical management of BPH. Forty-six of them (79.3%) had open prostatectomy whilst twelve (20.7%) had TURP with a mean age of 70.4 and 65.2 years respectively. The most common reason for the open prostatectomy was refractory retention of urine (76.0%) while that for TURP was lower urinary tract symptoms (58.3%). The mean prostate volume for the patients who had open prostatectomy was 64.2ml ± 28.7mls (range 23.0-121.0ml) while that of the TURP group was 40.1g ± 16.2mls (range 18.5-70.0mls). Of the open prostatectomy group, 67.4% of them had prostate volumes 75 mls or less. The blood transfusion and peri-operative complication rates for the open prostatectomy and TURP groups were 13% versus 8.3% and 8.7% versus 8.3% respectively. There was no mortality.

CONCLUSION

Access to TURP in the surgical management of BPH in Ghana is low (20.7%). With improved facilities including routine use of TRUS for assessing prostate size and availability of expertise for TURP, 67.4% of patients offered open prostatectomy presently could benefit from TURP, using prostate volumes 75mls (75g) or less as indication for TURP.

Retrocaval ureter: two case reports

Retrocaval ureter also referred to as pre-ureteral vena cava is a rare congenital anomaly with the ureter passing posterior to the inferior vena cava. Though it is a congenital anomaly, patients do not normally present with symptoms until the 3rd and 4th decades of life from a resulting hydronephrosis. We present the first two cases to be reported in Ghana; a 36-year-old male and a 40-year-old female both with right flank pains and associated right hydronephrosis. Diagnoses were confirmed with retrograde ureteropyelogram and both had an open surgical repair of the anomaly.

High prevalence of polyclonal hypergamma-globulinemia in adult males in Ghana, Africa

Chronic antigenic stimulation is associated with hypergamma-globulinemia. Higher rates of hypergamma-globulinemia in tropical populations are maintained even with migration to temperate regions. We conducted a population-based screening study to assess the prevalence and risk factors for hypergamma-globulinemia in Ghana, Africa. 917 Ghanaian males (50-74 years) underwent in-person interviews and health examinations. Serum from all persons was analyzed by electrophoresis performed on agarose gel; serum with a discrete/localized band was subjected to immunofixation. 54 persons with monoclonal proteins were excluded and 17 samples were insufficient for analysis. Using logistic regression and Chi-square statistics we analyzed patterns of hypergamma-globulinemia. Among 846 study subjects, the median γ-globulin level was 1.86 g/dL. On the basis of a U.S. reference, 616 (73%) had hypergamma-globulinemia (>1.6 g/dL) and 178 (21%) had γ-globulin levels >2.17 gm/dl. On multivariate analyses, lower education status (P = 0.0013) and never smoking (P = 0.038) were associated with increased γ-globulin levels. Self-reported history of syphilis was associated with hypergamma-globulinemia. We conclude that three quarters of this population-based adult Ghanaian male sample had hypergamma-globulinemia with γ-globulin levels >1.6 g/dL. Future studies are needed to uncover genetic and environmental underpinnings of our finding, and to define the relationship between hypergamma-globulinemia, monoclonal gammopathy of undetermined significance (MGUS), and multiple myeloma.

Prevalence of monoclonal gammopathy of undetermined significance among men in Ghana

OBJECTIVE

To determine the prevalence of monoclonal gammopathy of undetermined significance (MGUS), a precursor of multiple myeloma (MM), in Ghanaian men vs white men and to test for evidence to support an underlying race-related predisposition of the 2-fold higher prevalence of MGUS in African Americans vs whites.

PARTICIPANTS AND METHODS

Between September 1, 2004, and September 30, 2006, 917 men (50-74 years) underwent in-person interviews and physical examinations. Serum samples from all participants were analyzed by electrophoresis performed on agarose gel; any serum sample with a discrete or localized band was subjected to immunofixation. Age-adjusted and standardized (to the 2000 world population) prevalence estimates of MGUS and 95% confidence intervals (CIs) were computed in the Ghanaian men and compared with MGUS prevalence in 7996 white men from Minnesota. Associations between selected characteristics and MGUS prevalence were assessed by the Fisher exact test and logistic regression models.

RESULTS

Of the 917 study participants, 54 were found to have MGUS, yielding an age-adjusted prevalence of 5.84 (95% CI, 4.27-7.40) per 100 persons. No significant variation was found by age group, ethnicity, education status, or prior infectious diseases. The concentration of monoclonal immunoglobulin was undetectable in 41 (76%) of the 54 MGUS cases, less than 1 g/dL in 10 patients (19%), and 1 g/dL or more in only 3 patients (6%). Compared with white men, the age-adjusted prevalence of MGUS was 1.97-fold (95% CI, 1.94-2.00) higher in Ghanaian men.

CONCLUSION

The prevalence of MGUS in Ghanaian men was twice that in white men, supporting the hypothesis that race-related genetic susceptibility could explain the higher rates of MGUS in black populations. An improved understanding of MGUS and MM pathophysiology would facilitate the development of strategies to prevent progression of MGUS to MM.

Upper urinary tract stones in Accra, Ghana

Fifty-one patients with newly diagnosed upper urinary tract stones were seen at the Korle Bu Teaching Hospital, Accra over an 8 years period from September 1985 to August 1993. Their mean age was 40.1 years (range 20-61 years). The sex ratio was 36 males to 15 males. During the same period 3, 217, 135 patients (both adults and children) attended the hospital's clinics. Thus putting the incidence of upper urinary tract stone at 2 per 100,000. On presentation 37 patients had solitary stones, 11 had multiple stone and 3 had partial or complete staghorn calculi. A total of 71 stones were seen; 30 were renal and 35 ureteric. The etiology of the stone disease was established in only 10 cases (20%). Urinary stasis was a predisposing factors in 5 patients, urinary infection in 3 others and hyperuricaemia and uricosuria in another 2. Stones from 29 patients that were removed at surgery or passed spontaneously were analysed chemically. Of these 25 (86%) consisted of calcium oxalate and/or calcium phosphate, 3 (10%) consisted of magnesium ammonium phosphate and 1(4%) contained only uric acid.

Hemodialysis in the treatment of acute renal failure in tropical Africa: a 20-year review at the Korle Bu Teaching Hospital, Accra

From 1972 to 1992, 170 patients with acute renal failure (87 M, 83 F; mean age 32.51 +/- SE 0.945) underwent hemodialysis at the renal unit of the Korle Bu Teaching Hospital, Accra. Vascular access was established initially by arteriovenous shunt (133 cases), femoral venous cannulation (10 cases), and subclavian vein cannulation (27 cases). The overall mortality for acute renal failure (ARF) was 31.8% (54/170). The mortality for obstetric cases was 43.7% (14/32); for surgical cases, 33.3% (6/18); medical cases, 28.3% (13/32); and gynecologic (posthysterectomy) cases, 28.3% (2/7). The most important causes of death in ARF were pulmonary edema (42%), sepsis (20%), and cardiac tamponade (10.4%). Hemodialysis is now established as a form of treatment for ARF and a overall survival rate of 68.2% justifies the development of our program. With improvement of economies of developing countries and health insurance schemes, this form of treatment should be available in all developing countries.

Blackwater fever and acute renal failure in expatriates in Africa

From September 1976 to July, 1993, 7 patients---5 Europeans, 1 Filipino national, and 1 Korean---were admitted to the Renal Unit of Korle Bu Teaching Hospital in Ghana with acute renal failure due to severe malaria and intravascular hemolysis. All these patients had been in the Tropics 3 to 8 weeks and none were no malarial prophylaxis. All needed dialysis because of severe uremic symptoms. Four patients survived and 3 died. It is recommended that nationals from nonmalarial countries be counselled on the extreme importance of malarial prophylaxis when visiting Tropical areas where malaria is endemic.

Urethral stricture and semen quality

OBJECTIVE

To study the relationship between urethral stricture and infertility, which has not been well studied in the past.

PATIENTS AND METHODS

In this study in West Africa, the mean semen values from 90 fertile controls and 32 infertile controls were compared to 40 men with incomplete urethral strictures (IUS) and 56 men with complete urethral strictures after treatment. Testicular biopsies were performed on 30 patients. Sexually transmitted urethritis accounted for 79% of the strictures within this group of patients. Repair of the strictures restored ejaculate in 39 men, and 22 men had normospermia (20 million/mL); however, the remainder had either azoospermia or oligospermia. The biopsies revealed normal spermatogenesis in 5 men, which suggested ductal obstruction, but 14 patients had destruction of seminiferous tubules suggesting end organ failure. Eleven other men had hypospermatogenesis, maturation arrest, or premature sloughing of cells, which may be amenable to treatment.

CONCLUSIONS

These data suggest that early medical treatment and repair of urethral stricture may improve fertility for men with urethral strictures, especially strictures following infectious urethritis. Testicular biopsies may aid in the diagnosis of persistent infertility among these men, and should be considered as part of the work-up.

The use of small intestinal segments to replace diseased bilharzial ureters--a prospective study

Five male patients mean age 31.8 years with lower ureteric obstruction from urinary tract schistosomiasis have been treated by bilateral uretero-ileocystoplasty. All the 5 patients had bilateral hydroureters and hydronephrosts and 3 had reversible chronic renal failure whilst one patient presented with anuria and acute renal failure. Fibrosis of lower 1/4th to 1/3rd of the Ureters was present in the 5 patients. Four patients survived the operation for a mean of 3.4 years (range 1-7 years). The post-operative complications were hypernatraemic hyperchloraemic metabolic acidosis in 3 and incisional hernia in one. There was one death from septicaemia complicating infected bilateral nephrostomies performed before ureteroileocystoplasty. Ureteroileocystoplasty is recommended for replacement of damaged ureters where the extent of the damage precludes ureteroneocystostomy or where previous ureteroneocystostomy has failed.

HIV seropositive cases presenting as urological patients at the Korle-Bu Teaching Hospital, Accra--a preliminary report

Thirty-six patients (33 males, 3 females) were screened for HIV antibodies at the Urological clinics, at the Korle Bu Teaching Hospital, Accra because of chronic diarrhoea, unexplained weight loss, multiple sexual partners, recurrent sexually transmitted diseases, non resolution of symptoms or history of possible exposure to HIV. Ten patients (27.8%) were found to be HIV seropositive; 6 were confirmed as HIV-1, one as HIV-2 and 3 as both HIV-1 and HIV-2. The HIV seropositive patients presented as follows: recurrent cystitis and offensive vaginal discharge in 2 females, non-resolution or recurrence of urological symptoms and signs such as warts (genital, meatal and or urethral) in 4 males and recurrent penile ulcers in 4 males. This report indicates that physicians should be alert and screen high risk patients for both HIV-1 and HIV-2 antibodies.

Anuric acute renal failure due to bilateral accidental ureteric ligation during abdominal hysterectomy

OBJECTIVE

To determine the incidence of accidental ureteric ligation causing acute anuric renal failure (AARF) at the KorleBu Teaching Hospital, Accra, Between August 1984 and December 1991.

METHOD

The records and operative data of all cases managed with acute anuric renal failure at the hospital during the period were reviewed.

RESULT

The 7 patients with AARF presented with mean pre-referral anuria of 3.2 days. Total abdominal hysterectomy (4 for fibroids, 2 for carcinoma of uterus and 1 for post partum hemorrhage) was the cause of ureteric ligation. The 7 patients mean age 38.5 years were anemic (mean HB 4.1 g/dl) and uremic (mean blood urea 40.51 mmol/l) on admission. Abdominal ultrasonography was useful for diagnosis of obstructive uropathy. Hemodialysis was required in all cases prior to laparotomy and ureteroneocystostomy. The ureters were usually ligated at the distal 3 cm. Five survived ureteroneocystostomy and 2 died before laparatomy from septicemia and/or pulmonary edema.

CONCLUSION

Abdominal hysterectomy is a major cause of anuric acute renal failure and early recognition and treatment prevents death.

Etiological factors of male infertility in Africa

Of the 595 infertile African males studied, 192 (30.8%) were azoospermic and 413 (69.40%) had oligospermia. Azoospermia was caused by obstruction to the vas and/or epididymis in 44% of cases and testicular lesions in the remaining 56% of cases, whilst the oligospermia was probably caused by obstruction in 4.7% of cases and testicular lesions in 85.3%. Bilateral testicular biopsies were performed on 302 patients. A variety of pathological conditions were observed; the most prevalent was hypospermatogenesis, in 12% of cases. A significant portion (37.2%) of patients without testicular biopsies had clinically detectable testicular or epididymal abnormalities. There was a higher incidence (12%) of inflammatory testicular or prostatic conditions in this study as compared with those found in Europeans, suggesting that inflammatory conditions contribute more to male infertility in Africa. Only a single case of chromosomal abnormality was detected.

Vascular access for haemodialysis for renal failure in a developing country

One thousand two hundred and thirty-five haemodialyses have been performed on 92 patients with renal failure. The mean number of dialyses per patient was 13.42 and the survival rate was 60.9%. One hundred and six arteriovenous shunts (98 of arm, 7 of ankle, and one of groin) were created. Three arteriovenous fistulae of arm were created in 2 patients with chronic renal failure. All the operations were performed under local or regional block anaesthesia. The mean shunt complications were clotting (27.4%), bleeding (17.9%) and infection (13.2%). The complications associated with the fistulae were non-function, heart failure, infection, aneurysmal dilatation and bleeding. One death from heart failure was attributable to arteriovenous fistula. It is recommended that patients with renal failure requiring haemodialysis in developing countries should have shunts or fistulae created under regional anaesthesia to avoid the problems of general anaesthesia in uraemic patients.

Acute renal failure in tropical Africa

Between 1972 and 1975, 55 adult patients with acute renal failure were admitted to the renal unit of Korle Bu Hospital. Fourteen patients died, giving an overall death rate of 25%. Massive intravascular haemolysis after a short febrile illness was the commonest cause of acute renal failure. Clinically these patients presented with blackwater fever but in only one could Plasmodium falciparum malaria be confidently diagnosed. In half the patients various bacterial and viral infections (especially typhoid) could be incriminated as causing this blackwater fever syndrome. The incidence of glucose-6-phosphate dehydrogenase deficiency was 22.5%, but we could not confirm the impression of a greater predisposition to acute renal failure in patients with this enzyme defect.

Acute renal failure and typhoid fever

Over a two-year period, out of 40 adult Ghanaians admitted to the renal unit of Korle Bu Hospital with acute renal failure, 6 (15%) had typhoid fever. During this period approximately 500 cases of typhoid were admitted to this Hospital. Prominent features in these cases were a blackwater fever syndrome and leucocytosis. These features in a patient with typhoid should suggest the possibility of complicating acute renal failure. Three patients showed a deficiency of glucose-6-phosphate dehydrogenase (G-6-P.D.) in their red blood cells. It is suggested that typhoid is likely to be an important cause of acute renal failure in areas where it is endemic and G-6-P.D. deficiency common.

Acute renal failure and open heart surgery

A retrospective study of 428 open heart operations showed the incidence of mild and severe renal failure to be 26% and 4.7% respectively. The mortality rate was 38% in the mild cases and 70% in the severe cases. Only half of the patients whose death was associated with renal failure showed macroscopic or microscopic renal lesions at necropsy. The patients who developed renal impairment had significantly higher mean preoperative blood urea (40 mg/100 ml) than the non-renal-failure cases (33 mg/100 ml). Periods of perfusion over 60 minutes, mean perfusion pressures below 80 mm Hg, and multiple valve replacement operations also increased the incidence of renal failure. There was no statistical correlation between the age of individual patients, the degree of cooling, and postoperative blood urea values. There was no evidence to suggest that frusemide or mannitol separately or together influenced the development of renal failure. Peritoneal dialysis was preferred for initial treatment of patients with severe renal failure, and haemodialysis was required only in special cases.