IMMUNOLOGICAL ABNORMALITY IN PATIENTS WITH LYSINURIC PROTEIN INTOLERANCE

Lysinuric protein intolerance (LPI) is a rare hereditary disorder mani festing hyperammonemia induced by low levels of basic amino acids, the se low levels being due to the impaired transport of these acids in th e intestinal mucosa and the renal tubules. Low serum arginine levels a nd probably the consequently low in vivo levels of nitric oxide (NO), which against acts as a physiological and immunological mediator/modul ator, are thought to influence the immunological status in patients wi th LPI. Accordingly, this study was conducted to. We found that patien ts with LPI had leukocytopenia, high serum IgG levels, a high ratio of CD44B4-positive lymphocytes (helper inducer) to CD42H4-positive lymph ocytes (suppressor inducer), low levels of leukocyte phagocytic, cytot oxic, and natural killer cell activity, and increased spontaneous prol iferation of lymphocytes. These results were probably the consequence of persistent low NO levels in vivo.