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Background A retrospective study examining incidence of CJD in South Western Sydney local health district (SWSLHD) from 2014 to 2020 showed that the reports of this disease exceeded national average of 1 per million. This exceeded the reported national, as well as international, averages. No epidemiological connection could be established between the individual cases nor a plausible explanation could be found behind the higher-than-expected cases.Methods 31 probable CJD cases were identified from this cluster; 4 were deemed to be non-CJD cases, due to lack of further supporting evidence on follow up. A further two were cases of familial CJD, whilst 14 cases did not have a post-mortem brain tissue available for testing. The remaining 11 cases were typed, based on their glycoprotein types and polymorphism at codon 129 of PRNP gene.Results In amongst the 11 cases of biopsy-proven, definitive, cases of CJD from this cluster, 6 belonged to Glycotype 3, 4 cases to Glycotype 2 and one case belong to Glycotype 1. From amongst the 6 Type 3 Glycotypes, 3 cases had MM3 mutation at codon 129 and one case each was identified with MV3 and VV3 mutations at codon 129.Conclusion No clear association between glycotypes, genotypes and demographics could be established from among the 11 patients comprising this study. These findings further underpin our lack of understanding and the challenges associated with elucidating the sporadic CJD clusters that are now being frequently reported in literature.