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Background Fanconi anemia (FA) is phenotypically diverse, hereditary condition associated with bone marrow failure, multiple physical abnormalities, and an increased susceptibility to the development of malignancies. Less recognized manifestations of FA include endocrine abnormalities. International discourse has highlighted that these abnormalities are widespread among children and adults with FA. To date there has been no systematic study that has evaluated the endocrine abnormalities in a cohort of patients with FA, homozygous for a founder mutation (c.637_643del (p.Tyr213Lysfs*6)) in FANCG. The objectives of the study were to evaluate endocrine gland function in patients with FA of a single FA genotype, and to determine the frequency and nature of endocrine abnormalities in this group. Methods Cross‐sectional, descriptive study of 24 South African patients of African ancestry with FA (homozygous for a FANCG founder mutation). Outcomes measured included growth, pubertal status, growth hormone axis screening, thyroid gland function, glucose and insulin metabolism and bone age (BA). Results Endocrine dysfunction was present in 70.8% (17 of 24), including abnormal insulin‐like growth factor 1 (IGF‐1)/insulin‐like growth factor‐binding protein 3 (IGFBP‐3) in 25.0% (6 of 24), insulin resistance in 41.7% (10 of 24), abnormal thyroid function in 16.7% (4 of 24) and short stature in 45.8% (11 of 24). No abnormalities of glucose metabolism were identified. Abnormal pubertal status was seen in three males (12.5%). Abnormal BAs were present in 34.8% (8 of 23). Conclusion Endocrine abnormalities occur at a high frequency in patients with FA, homozygous for a FANCG founder mutation, similar to other FA cohorts. Our data are specific to FA patients with a single genotype, and therefore provide the first genotype‐phenotype information on endocrine abnormalities in South African patients, homozygous for a FANCG founder mutation. Recommendations regarding endocrine screening in this patient subgroup are made, including, but not limited to, baseline testing of thyroid function, fasted insulin and glucose, and IGF‐1 and IGFBP‐3., Endocrine abnormalities are a lesser known complication of Fanconi anemia. Endocrine abnormalities occur at a high frequency in South African patients with Fanconi anemia, homozygous for a FANCG founder mutation.

Fanconi Anaemia (FA) is an autosomal recessive disorder characterised by defects in DNA repair, associated with chromosomal instability and cellular hypersensitivity to DNA cross-linking agents such as mitomycin C (MMC). The FA repair pathway involves complex DNA repair mechanisms crucial for genomic stability. Deficiencies in DNA repair genes give rise to chromosomal radiosensitivity. FA patients have shown increased clinical radiosensitivity by exhibiting adverse normal tissue side-effects. The study aimed to investigate chromosomal radiosensitivity of homozygous and heterozygous carriers of FA mutations using three micronucleus (MN) assays. The G0 and S/G2MN assays are cytogenetic assays to evaluate DNA damage induced by ionising radiation in different phases of the cell cycle. The MMC MN assay detects DNA damage induced by a crosslinking agent in the G0 phase. Patients with a clinical diagnosis of FA and their parents were screened for the complete coding region of 20 FA genes. Blood samples of all FA patients and parents were exposed to ionising radiation of 2 and 4Gy. Chromosomal radiosensitivity was evaluated in the G0 and S/G2 phase. Most of our patients were homozygous for the founder mutation FANCG c.637_643delTACCGCC; p.(Tyr213Lysfs*6) while one patient was compound heterozygous for FANCG c.637_643delTACCGCC and FANCG c.1379G > A, p.(Gly460Asp), a novel missense mutation. Another patient was compound heterozygous for two deleterious FANCA mutations. In FA patients, the G0- and S/G2-MN assays show significantly increased chromosomal radiosensitivity and genomic instability. Moreover, chromosomal damage was significantly elevated in MMC treated FA cells. We also observed an increase in chromosomal radiosensitivity and genomic instability in the parents using 3 assays. The effect was significant using the MMC MN assay. The MMC MN assay is advantageous as it is less labour intense, time effective and has potential as a reliable alternative method for detecting FA patients from parents and controls.

Background: Despite the rampant human immunodeficiency (HIV) epidemic in Africa, there is a paucity of published data of HIV-related Epstein-Barr virus-associated smooth muscle tumours (EBV-SMT) from Africa.Methods: We embarked on retrospective documentation of the clinicopathological features of confirmed HIV-related EBV-SMT over a 5-year time frame at the largest hospital in Africa. All haematoxylin and eosin stained tissue sections, immunohistochemistry and EBV in situ hybridisation (ISH) investigations were reviewed in conjunction with clinical data.Results: Fourteen (n = 14) EBV-SMT were confirmed in 13 patients (age range: 10–53 years). Five paediatric patients and a predominance of females (70%) were evident in this series. All patients were HIV seropositive and CD4 counts ranged from 1 to 1331 cells/ul (median 355 cells/ul; mean 442 cells/ul). Tumour-associated pain was a common symptom in the paediatric age group, while neurological symptoms were frequent in the adults due to paraspinal c...

BACKGROUND Little is known on the risk of cancer in HIV-positive children in sub-Saharan Africa. We examined incidence and risk factors of AIDS-defining and other cancers in pediatric antiretroviral therapy (ART) programs in South Africa. METHODS We linked the records of five ART programs in Johannesburg and Cape Town to those of pediatric oncology units, based on name and surname, date of birth, folder and civil identification numbers. We calculated incidence rates and obtained hazard ratios (HR) with 95% confidence intervals (CI) from Cox regression models including ART, sex, age, and degree of immunodeficiency. Missing CD4 counts and CD4% were multiply imputed. Immunodeficiency was defined according to World Health Organization 2005 criteria. RESULTS Data of 11,707 HIV-positive children were included in the analysis. During 29,348 person-years of follow-up 24 cancers were diagnosed, for an incidence rate of 82 per 100,000 person-years (95% CI 55-122). The most frequent cancers were Kaposi Sarcoma (34 per 100,000 person-years) and Non Hodgkin Lymphoma (31 per 100,000 person-years). The incidence of non AIDS-defining malignancies was 17 per 100,000. The risk of developing cancer was lower on ART (HR 0.29, 95%CI 0.09-0.86), and increased with age at enrolment (>10 versus

The spectrum of sickle cell disease (SCD) encompasses a heterogeneous group of disorders that include: (i) homozygous SCD (HbSS), also referred to as sickle cell anaemia; (ii) heterozygous SCD (HbAS), also referred to as sickle cell trait; and (iii) compound heterozygous states such as HbSC disease, HbSβ thalassaemia, etc. Homozygous or compound heterozygous SCD patients manifest with clinical disease of varying severity that is influenced by biological and environmental factors, whereas subjects with sickle cell trait are largely asymptomatic. SCD is characterised by vaso-occlusive episodes that result in tissue ischaemia and pain in the affected region. Repeated infarctive episodes cause organ damage and may eventually lead to organ failure. For effective management, regular follow-up with support from a multidisciplinary healthcare team is necessary. The chronic nature of the disease, the steady increase in patient numbers, and relapsing acute episodes have cost implications that are likely to impact on provincial and national health budgets. Limited resources mandate local management protocols for the purposes of consistency and standardisation, which could also facilitate sharing of resources between centres for maximal utility. These recommendations have been developed for the South African setting, and it is intended to update them regularly to meet new demands and challenges.

Background. Nephroblastoma is the commonest renal tumour seen in children. It has a good prognosis in developed countries with survival rates estimated to be between 80% and 90%, while in Africa it remains low.Method. Retrospective study of patients diagnosed with nephroblastoma who are seen at 4 paediatric oncology units, representing 58.5% of all South African children with nephroblastoma and treated following SIOP protocol between January 2000 and December 2010.Results. A total of 416 patients were seen at the 4 units. Over 80% of our patients were African and almost 10% of mixed ethnicity. The most common stage was stage 4. The median survival was 28 months after diagnosis with the mixed ethnicity patients recording the longest duration (39 months) and the white patients had the shortest median survival. The overall 5-year survival rate was estimated to be 66%. Stage 2 patients did significantly better (85%).Conclusions. Our patients are similar with regard to gender ratio, median age, and age distribution as described in the literature, but in South Africa the more advanced stage disease seen than in other developed countries is translated into low overall survival rate.

Fanconi anemia (FA) is a rare disorder of DNA repair, associated with various somatic abnormalities but characterized by hematological disease that manifests as bone marrow aplasia and malignancy. The mainstay of treatment, in developed nations, is hematopoietic stem cell transplantation (HSCT) with subsequent surveillance for solid organ and non-hematological malignancies. In South Africa, FA in the Black population is caused by a homozygous deletion mutation in the FANCG gene in more than 80% of cases. Many affected patients are not diagnosed until late in the disease course when severe cytopenia and bone marrow aplasia are already present. Most patients are not eligible for HSCT at this late stage of the disease, even when it is available in the state health care system. In this study, the hematological presentation and disease progression in 30 Black South African patients with FA, confirmed to have the FANCG founder mutation, were evaluated and compared to those described in other FA cohorts. Our results showed that patients, homozygous for the FANCG founder mutation, present with severe cytopenia but progress to bone marrow failure at similar ages to other individuals affected with FA of heterogeneous genotype. Further, the incidence of myelodysplastic syndrome is similar to that which has been previously described in other FA cohorts. Although severe cytopenia at presentation may be predicted by a higher number of somatic anomalies, the recognition of the physical FA phenotype in Black South African patients is challenging and may not be useful in expediting referral of suspected FA patients for tertiary level investigations and care. Given the late but severe hematological presentation of FA in Black South African patients, an investigative strategy is needed for earlier recognition of affected individuals to allow for possible HSCT and management of bone marrow disease.

Fanconi anemia is a genotypically and phenotypically heterogeneous condition, characterized microscopically by chromosomal instability and breakage. Affected individuals manifest growth restriction and congenital physical abnormalities; most progress to hematological disease including bone marrow aplasia. Black South African Fanconi anemia patients share a common causative founder mutation in the Fanconi G gene in 80% of cases (637_643delTACCGCC). The aim of this study was to investigate the genotype-physical phenotype correlation in a cohort of individuals homozygous for this mutation.Thirty-five black patients were recruited from tertiary level hematology/oncology clinics in South Africa. Participants were subjected to a comprehensive clinical examination, documenting growth, congenital anomalies, and phenotypic variability.Descriptive statistical analysis showed significant growth abnormalities in many patients and a high frequency (97%) of skin pigmentary anomalies. Subtle anomalies of the eyes, ears, and hands occurred frequently (≥70%). Apart from malformations of the kidney (in 37%) and gastrointestinal tract (in 8.5%), congenital anomalies of other systems including the cardiovascular and central nervous systems, genitalia, and vertebrae were infrequent (5%).The diagnosis of Fanconi anemia in black South African patients before the onset of hematological symptoms remains a clinical challenge, with the physical phenotype unlikely to be recognized by those without dysmorphology expertise.

Introduction Fanconi Anaemia (FA) is an autosomal recessive disorder characterized by defects in DNA repair associated with chromosomal instability and cellular hypersensitivity to DNA cross-linking agents such as mitomycin C (MMC). The clinical manifestation includes congenital and developmental abnormalities and bone marrow failure. FA also has a predisposition to cancer. Fifteen different genetic subtypes of FA have been described. In South Africa, with mixed ethnicity in the population, prevalence of FA ranges between is 1/22 000 for the white Afrikaners to 1/40 000 in the black South Africans. Evidence suggests that FA patients are chromosomally radiosensitive to ionising radiation but with very limited data. The aim of this study is to investigate chromosomal radiosensitivity and genomic instability of homozygous and heterozygous carriers of FA mutations compared to healthy individuals using the micronucleus (MN) assay. Materials and methods For the G0 MN assay, heparinised blood in culture medium was irradiated at 0 Gy (Baseline), 2 Gy and 4 Gy followed by the immediate stimulation of lymphocytes using phytohaemagglutinin (PHA). Cytochalasin B was added 23 hours later to inhibit cytoplasmic division. Cells were harvested 70 hours later. For the S/G2 MN assay, we used the same radiation doses but the culture was only irradiated 72 hours after addition of PHA. To detect DNA damage in the S/G2 phase of the cell cycle, the cells were harvested 8 hours post irradiation. The third assay is similar as the G0 MN assay except the cell damage is induced using MMC. All slides were stained with acridine orange and micronuclei were scored using a fluorescent microscope. Results The micronuclei frequencies are higher in the homozygous carriers compared to the heterozygous carriers and healthy individuals. Conclusions FA mutation carriers show higher chromosomal radiosensitivity and genomic instability compared to healthy individuals.

Background. Childhood cancer is an emerging problem in Africa. Its extent is hazy because data are scarce, but it should be addressed. This is the first report from the South African Children’s Tumour Registry (SACTR), which covers the whole of South Africa (SA). It provides minimal estimates of cancer incidence and discusses the challenges of cancer surveillance and control in a child population in a middle-income country. Only about 2% of the African population is covered by cancer registries producing comparable incidence data. Objective. To present and interpret incidence patterns and trends of childhood cancer over a 21-year period. The results should raise awareness of the problem of childhood cancer in an African population and provide sensible data for taking this problem in hand. Methods. All eligible and validated cancer cases registered in the SACTR over the period 1987 - 2007 and classified according to the International Classification of Childhood Cancer were included. Population data were retrieved from official sources and estimated for the population subcategories. Incidence rates were standardised to the world standard and time trends were evaluated using joinpoint models, adjusting for sex and age. Results. Based on the 11 699 cases, the overall age-standardised average annual incidence rate was 45 per million. Threefold differences in the overall incidence rates were observed between the ethnic groups, ranging from 116 for whites to 37 for black Africans, and they differed by diagnostic group. Differences between the nine provinces of SA relate to the ethnic composition and prevailing socioeconomic status. The overall incidence rate declined by 1.2% per year for the whole country ( p

Background. Fanconi anaemia (FA) is an autosomal recessive, genetically heterogeneous disorder, characterised by interstrand crosslink-induced chromosome breaks, congenital abnormalities and predisposition to malignancies. It has a prevalence of about 1/40 000 in black South Africans (SAs). A founder mutation in the FANCG gene occurs in the homozygous state in 77.5% of southern African blacks. Objective. To locate additional pathogenic mutations in the FANCG gene of black FA patients who were heterozygous for the founder mutation. Methods. Further mutation analysis of the FANCG gene was undertaken in 7 patients clinically suspected of having FA. The parents of two of the patients were tested for the presence of the founder mutation to determine true heterozygosity in the patients. To clarify whether or not previously unreported variants were pathogenic, 58 random black SA individuals were screened. Results. Three novel single base pair deletions, resulting in frameshift mutations (c.247delA, c.179delT and c.899delT) were identified in 3/7 patients. A fourth patient was found to have a single base substitution resulting in a splice site mutation (c.1636+1G>A). The remaining three patients were not found to harbour any pathogenic mutations. Two non-pathogenic variants were also identified among the seven patients. Conclusion. The results of this small sample suggest that a second common mutation in the FANCG gene is unlikely in this population. However, FANCG sequencing should be performed on patients heterozygous for the common founder mutation to attempt to confirm their diagnosis.