Prealbumina, precalicreína e protrombina na forma hepatesplênica da esquistossomose: catabolismo aumentado de proteínas da coagulação? Prealbumin, prekallikrein and prothrombin in hepatosplenic schistosomiasis: increased turnover of the clotting proteins?

Abstract

No plasma de 20 doentes portadores da forma hepatesplênica da esquistossomose mansônica, assim como no de 18 indivíduos normais, foram avaliados pré-albumina, precalicreína (atividade amidolítica) e protrombina-antígeno. Os valores da concentração plasmática de pré-albumina obtidos no grupo controle permitiram que se estabelecesse um intervalo de referência (0,5 — 99,5%) de 97 — 389 mg/I. Valores anormalmente diminuídos de pré-albumina encontrados em 2 dos doentes indicaram nestes uma disfunção hepatocítica de síntese protêica. Nos 18 doentes restantes a média da pré-albumina (232 ± 13 mg/l) não diferiu (p > 0,05) da do grupo controle (243 ± 11 mg/l) enquanto as médias da atividade de pró-calicreina (34 ± 1 μKat/l) e protrombina (81 ± 3,0 mg/l) estavam significativamente diminuídos no grupo de esquistossomóticos (p Prealbumin, prekallikrein and prothrombin were evaluated in 20 patients with the hepatosplenic form of schistosomiasis and in 18 subjects of a control group. With the prealbumin concentration values obtained in the latter group a reference interval (0.5 — 99.5%) of 97 to 389 mg/L was calculated and plasma levels below 97 mg/L assessed in 2 patients a deficiency in hepatic synthetic capacity. Mean (± SEM) prealbumin concentration in the 18 remaining patients (232 ± 13 mg/L) did not differ (p > 0.05) from that of the control group (243 ± 11 mg/L). Otherwise these 18 patients had both mean plasma prekallikrein (34 ± 1.3 /μKat/L) and prothrombin-antigen (81 ± 3 mg/L) concentrations lower (p < 0.01) than those of the control group (40 ± 1.4 μKat/L and 100 ± 3 mg/L, respectively). The present findings do not necessarily rule out the possibility that prekallikrein and prothrombin may asses a minimal hepatocellular damage earlier than prealbumin; but, since the latter protein have a shorter half-life than the formers and is a reliable index of hepatic synthetic capacity, the present report supports the hypothesis of an increased turnover of clotting proteins in some patients with the hepatosplenic form of schistosomiasis.