versión On-line ISSN 2078-5151
versión impresa ISSN 0038-2361
S. Afr. j. surg. vol.46 no.3 Cape Town ago. 2008
S. B. IbirogbaI; U. AlgarII; P. A. GoldbergIII; M. DuffieldIV; A. VorsterV; R. RamesaarVI
IM.B. B.S., F.C.S. (S.A.); Colorectal Unit, Department of Surgery, Groote Schuur Hospital and University of Cape Town
IIM.SC. (NURSING); Colorectal Unit, Department of Surgery, Groote Schuur Hospital and University of Cape Town
IIIM.B. CH.B., F.C.S. (S.A.), M.MED. (SURG.); Colorectal Unit, Department of Surgery, Groote Schuur Hospital and University of Cape Town
IVM.B. CH.B., L.R.C.P., M.R.C. (PATH.), F.S. (EDIN/GLASGOW), M.MED. (ANAT. PATH.); Division of Anatomical Pathology, Groote Schuur Hospital and University of Cape Town
VM.SC; Division of Human Genetics, Groote Schuur Hospital and University of Cape Town
VIPH.D; Division of Human Genetics, Groote Schuur Hospital and University of Cape Town
BACKGROUD: Hereditary mixed polyposis syndrome is characterised by multiple large-bowel polyps of differing histological types including a mixture of atypical juvenile polyps, hyperplastic polyps and adenomas. Affected individuals are thought to have an increased risk of malignancy, possibly via the juvenile polyposis pathway.
METHODS: A 51-year-old woman (with a history of a colectomy for polyps during childhood) presented with rectal bleeding. Endoscopy demonstrated small rectal polyps which were hyperplastic on histology. A family tree was drawn up and the three children of the proband underwent flexible sigmoidoscopy.
RESULTS: Endoscopic surveillance of the three children revealed one who had a similar phenotype to the mother. This child underwent colectomy and ileorectal anastomosis. The pathological specimen revealed more than 70 polyps, with a combination of juvenile retention, hyperplastic, adenomatous and inflammatory polyps. A second child had multiple small hyperplastic polyps, and the third had a normal colon. Although the gene locus for the disorder has been mapped, neither the gene nor the disease-causing mutation has been defined.
CONCLUSION: A rare inherited polyposis syndrome has been identified in a South African family. Where clinical suspicion of a possible inherited condition exists, investigating at-risk first-degree relatives confirms the inherited nature of the disease. It is possible to use genetic haplotyping (i.e. with a range of markers in the area of the gene) to provide statistical risk to immediate relatives and therefore those at highest risk.
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1. Whitelaw SC, Murday VA, Tomlinson IPM, et al. Clinical and molecular features of the hereditary mixed polyposis syndrome. Gastroenterology 1997; 112:327-334. [ Links ]
2. Murday V, Slack J. Inherited disorders associated with colorectal cancer. Cancer Surv 1989; 8: 139-157. [ Links ]
3. Jaeger EEM, Woodford-Richins KL, Lockett M, et al. Ancestry Ashkenazi haplotype at the HMPS/CRAC I Locus on 15q 13-q 14 is associated with hereditary mixed polyposis syndrome. Am J Human Genet 2003; 72: 1261-1267. [ Links ]
4. Peng H, Cao X, Li HH, et al. Haplotype and linkage analysis in Chinese hereditary mixed polyposis syndrome. Zhongha Wei Chang Wai Ke Za Zin 2005; 8(4): 312-315. [ Links ]
5. Tomlinson I, Nazneen R, Ian F, et al. Inherited susceptibility to colorectal adenomas and carcinomas. Evidence for new predisposition gene on 15q14-q22. Gastroenterology 1999; 116: 789-795. [ Links ]
6. X Cao, Kw Eu, Kumarasinghe MP, et al. Mapping of hereditary mixed polyposis syndrome (HMPS) to chromosome 10q23 by genomewide high density single nucleotide polymorphism (SNP) SCAN and identification of BMPRIA loss of function. J Med Genet 2006; 43(3): e13. [ Links ]