Creutzfeldt-Jakob disease (CJD) is a transmissible, fatal degenerative disorder of the CNS. CJD is known in a sporadic, familial and iatrogenic form. Iatrogenic form has been accidentally induced through corneal and dura mater transplantation or surgical procedures. The largest number of iatrogenic CJD developed in patients who had received human growth hormone (hGH). The minimal incubation period appears to be 4-15 years, the maximal 21-30 years after receiving hGh treatment. An increasing number of new CJD cases in hGH recipients in France, providing evidence of unusually long incubation period and an occurrence of genetically controlled (mutation E200K carrier) CJD-risk group in Slovak population induced this second investigation of hGh treated patients. The aim of this study is to verify whether the absence of CJD in hGH recipients in Slovakia reflects the actual epidemiological situation or a lack of informations. The objective of the study was to investigate signs of clinical manifestation of CJD and to perform molecular genetic study on prion protein (PrP) gene in hGh recipients.
Patients and methods: 32 hGH treated patients (23 men and 9 women) at the age of 17-38 years were investigated. The occurrence of codon 200 (E200K) mutation and polymorphism at codon 129 of PrP gene was studied.
Results: Neurological, including cerebellar signs of CJD, intellectual or psychological changes were not observed in investigated patients. The shortest duration of hGH treatment was 2 years, the longest 9 years. The time interval since the beginning of hGH administration was 12-19 years. Restriction endonuclease analysis of the PrP gene revealed one patient with E200K mutation, 8 patients homozygous for methionin, 2 patients homozygous for valin and 16 heterozygous patients at codon 129.
Conclusion: No evidence of CJD has been observed in investigated group of hGH recipients. Considering the long incubation period of hGH-induced CJD and the obtained results, clinical and genetic investigation on the whole relatively small group of Slovak hGH recipients is recommended. (Tab. 2, Fig. 1, Ref. 22.)