Article

Pathogenesis of alcoholic neuropathy.

1st Dept of Neurology, University Hospital, LFUK, Mickiewiczova 13, 813 69 Bratislava, Slovakia.
Bratislavske lekarske listy (Impact Factor: 0.45). 02/2002; 103(1):26-9.
Source: PubMed

ABSTRACT Chronic alcoholism is a medical, economical and social problem. Motility and mental function disorders are among the complications of chronic alcoholism and have been known for more than two centuries as "alcoholic paralysis", and are caused by alcoholic neuropathy. The pathogenesis of alcoholic neuropathy does not appear to be identical with central nervous system disorders which are caused by chronic alcoholism and it seems that it results from a failure of the protection barrier systems in the peripheral nervous system. To the pathogenesis of alcoholic neuropathy includes: 1. direct toxic effects of alcohol on the cellular population of the central nervous system and other tissues, especially of parenchymatous organs (in particular of the liver), 2. indirect metabolic and exotoxic changes mediated by malabsorption, maldigestion and secondary caloric and energy deprivation, 3. effects of genetic factors. (Fig. 2, Ref. 23.)

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Despite heterogeneity of the neurological manifestations in our patients with acute porphyria, the major pattern of PNP associated with abdominal pain, dysautonomia, CNS involvement and mild hepatopathy could be demonstrated. If more strict inclusion criteria for biochemical abnormalities (>10-fold increase in excretion of urinary PBG) are applied, neurological manifestations in an acute attack are probably more homogeneous than described previously, which suggests that some of the neurological patients described previously may not have acute porphyria but rather secondary porphyrinuria. Screening for acute porphyria using urinary PBG is useful in a selected group of neurological patients with acute PNP or encephalopathy and seizures associated with pain and dysautonomia. Clinical manifestations and the outcome of acute attacks were used as a basis for developing a 30-score scale of the severity of an acute attack. 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Erythrocyte HMBS activity did not correlate with the porphobilinogen excretion in remission or the clinical of the disease. In all AIP severity patients, normal PBG excretion predicted freedom from acute attacks. Urinary PBG excretion together with gender, age at the time of diagnosis and mutation type could predict the likelihood of acute attacks in AIP patients. Neurologiset löydökset ja molekyyligenetiikka äkillisessä jaksottaisessa porfyriassa Lounais-Venäjän alueella. Äkillinen jaksottainen porfyria kuuluu hemin biosynteesihäiriöihin, jotka ovat perinnöllisiä aineenvaihdunsairauksia. Lääkkeet, paasto tai hormonaaliset muutokset elimistössä lisäävät hemin muodostumista maksassa ja entsyymin puutteesta kärsivät potilaat keräävät porfyriinien esiasteita kehoonsa. Nämä esiasteet ovat myrkyllisiä hermokudokselle. Tauti ilmenee siten äkillisenä kohtauksena, joka alkaa usein lievillä psyykkisillä oireilla kuten unettomuudella ja levottomuudella ja etenee autonomisen hermoston häiriöihin, jossa tyypillisimpänä oireena on voimakas vatsakipu. Jos kohtaus etenee, potilaalle voi kehittyä lihasheikkoutta, kouristuksia ja tajunnantason laskua, ja siten se voi olla henkeä uhkaava tilanne. Nykyisin varhaisen diagnostiikan ja hoidon seurauksena neurologiset ilmentymät ovat harvinaisia, mutta osa äkillistä porfyriaa sairastavista potilaista on selvästi alttiimpia halvauksille. Akuutti porfyria varmistetaan virtsanäytteestä, josta mitataan porfyriinien esiasteet. Kohtauksen aikana ne ovat selkeästi koholla ja diagnoosi varmistetaan myöhemmin geenitestillä. Tämän tutkimuksen tarkoituksena oli selvittää äkillistä porfyriaa sairastavien esiintyvyys Pietarin alueella. 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