Browsing by Author "Schoeman, M."

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    Cancer genetics : an approach to suspected hereditary breast or colorectal cancer
    (Health & Medical Publishing Group, 2019) Scott, C. J.; Schoeman, M.; Urban, M. F.
    ENGLISH ABSTRACT: Two of the most common cancers are breast cancer and colorectal cancer. Up to 10% of cases of each are associated with a high risk of recurrence in an affected individual, or of occurrence in biological relatives. This results from the presence of an underlying mutation (or ‘pathogenic variant’) in a high-penetrance gene. Such cases are typically associated with an autosomal dominant pattern of inheritance, although this may not be obvious in the family history. Genetic testing can identify many (but not all) of these cases, and should be offered to those whose family history or clinical features suggest a high risk. Although testing for certain risk genes (e.g. BRCA1 or BRCA2) has been available for years, the advent of next-generation sequencing ‘gene panels’ now allows for simultaneous testing of many more genes at lower cost. This allows for more frequent detection of pathogenic variants in underlying genes than in the past, but also makes interpretation more complex. An index of suspicion for genetic cancers and appropriate referral to a genetics health professional are increasingly important.
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    Folate levels in patients with ulcerative colitis receiving sulphasalazine
    (Health & Medical Publishing Group, 1984) Schoeman, M.; Bezuidenhout, D. J. J.
    The question of folate deficiency in patients receiving sulphasalazine is still controversial. A random sample of patients with ulcerative colitis receiving sulphasalazine were studied to determine the clinical significance of the inhibition of folic acid absorption by the drug. No significant lowering of folate levels could be determined.
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    Predicted v. real prevalence of the 22q11.2 deletion syndrome in children with congenital heart disease presenting to Red Cross War Memorial Children’s Hospital, South Africa : a prospective study
    (Health & Medical Publishing Group, 2016) De Decker, R.; Bruwer, Z.; Hendricks, L.; Schoeman, M.; Schutte, G.; Lawrenson, J.
    Background. The 22q11.2 deletion syndrome (22qDS) has more than 180 associated phenotypic features, yet genotype-phenotype correlation remains obscure. Since many of the clinical characteristics are serious, yet treatable (including congenital heart disease), clinicians must maintain a high index of clinical suspicion to recognise a suite of co-occurring phenotypic features that suggest a diagnosis of 22qDS. Óskarsdottir’s scoring schedule (the ‘O score’) is generally used to suggest the need for confirmatory fluorescent in situ hybridisation (FISH) testing, using the TUPLE 1 probe. An O score of two or more indicates the need for FISH testing. Objectives. A previous audit of FISH-positive results of patients with congenital heart disease at Red Cross War Memorial Children’s Hospital (RCWMCH) revealed a clinical recognition rate of 1.7%. However, we were concerned that the syndrome may be under-recognised in our setting. Our aims were therefore to assess the predictive value of ‘O scoring’ and to accurately determine the prevalence of 22qDS in our patient population. Methods. A prospective trial of FISH testing every new patient with congenital heart disease presenting to RCWMCH was undertaken to accurately determine the prevalence of 22qDS. The results were then compared with the ability of the O score to indicate the need for FISH testing. Results. Testing of 125 patients detected deletions in six (4.8%, 2.8 times the previously determined clinical detection rate), thereby vindicating our concern that 22qDS is under-diagnosed. Of these 125 patients, 37 had an O score of 2 or 3, yet only 6 were FISH-positive, giving the O score a positive predictive value of only 14%. Conclusion. Until a more robust alternative recognition tool is available, South African clinicians should use all clinical recognition criteria liberally to suggest the need for formal testing for 22qDS.