ABSTRACT:Background: Parkinson's disease (PD) patients frequently report a family history of PD and this may provide etiological clues to PD. It has also been suggested that a report of a negative family history is reliable. We studied the prevalence of PD in relatives of PD patients to assess the reliability of family history and to evaluate possible explanations of "familial PD"(fPD). Methods: 81 of 650 (12.5%) PD probands (all PD patients seen at clinic in 4 years) reported a positive family history of PD. Each fPD proband was matched with non-familial PD (nfPD) proband by gender and year of birth. Screening and follow-up questionnaires were mailed to relatives to obtain information concerning pedigree and presence of neurodegenerative disease. Available family members (regardless of disease status) were examined. Results: On examination, 8 persons, said to be "normal" by probands, relatives and themselves, had definite or possible PD (5 fPD, 3 nfPD). The prevalence rate of PD among first and second degree living relatives of probands varied significantly between fPD and nfPD groups (6269/100 000 versus 1190/100 000; p < 0.001). The weighted prevalence (taking into account the proportions of fPD and nfPD within the clinic) was 1822/100 000, a value more than 5 times higher than reported prevalence rates of PD in the general population (p < 0.001). The prevalence rate was greater in first degree relatives than second degree. Conclusions: "Familial parkinsonism" cannot be explained merely by size of or advanced age within families. Significant numbers of previously unrecognized PD patients may be identified despite a "negative" family history. That is, the patient's report of an absence of familial parkinsonism is frequently inaccurate. The prevalence rate in relatives of PD patients appears to be higher than the general population -regardless of the family history reported by a PD patient. We believe our study suggests that genetic influences or early life environmental exposures are likely to be of etiological importance in PD. RESUME: "Maladie de Parkinson familiale" -Une etude familiale cas-temoins. Introduction: Les patients atteints de la maladie de Parkinson (MP) rapportent souvent une histoire familiale de MP, ce qui pourrait fournir des indices etiologiques sur la MP. 11 a egalement ete suggere qu'on peut se fier a une histoire familiale negative fournie par le patient. Nous avons etudie la prevalence de la MP chez les apparentes de patients atteints de la MP pour evaluer la fiabilite de l'histoire familiale et identifier des explications possibles dans la "MP familiale". Methodes: 81 des 650 (12.5%) des propositi (tous les patients examines a la clinique en 4 ans) ont rapporte une histoire familiale positive de MP. Chaque cas familial de MP (fMP) a ete apparie pour le sexe et l'annee de naissance a un cas non familial (nfMP). Des questionnaires de depistage et de suivi ont ete postes aux apparentes pour obtenir de l'information concernant l'arbre genealogique et la presence de maladies neurodegenerati...

We report the first description of a patient with parkinsonism induced by solvent abuse. Our patient developed parkinsonism acutely, following heavy abuse of lacquer thinner. Her clinical deficits were indistinguishable from idiopathic parkinsonism (Parkinson's disease) and she responded to levodopa. Parkinsonism has persisted for more than 3 months. Brain computed tomography was normal. Positron emission tomographic studies showed normal fluorodopa uptake and reduced raclopride binding, indicating an unusual disturbance of striatal dopaminergic function. This patient suggests that organic solvents may cause parkinsonism in susceptible individuals.

No abstract