実験モデルにおけるアカントアメーバ角膜炎に対するニタゾキサニドの治療効果

Acanthamoeba keratitis (AK) is a severe infection caused by opportunistic protozoa called Acanthamoeba species, especially in contact lens wearers and immunocompromised people. The aim of the study was to assess the therapeutic efficiency of two nitazoxanide (NTZ) formulations in treating experimentally induced AK. Seven groups of 31 male New Zealand white rabbits were formed: Group (A-s) was infected and administered NTZ in suspension form; Group (A-c): the control group of the previous; Group (B-s): infected and administered NTZ in liquid crystal forming system; Group (B-c): the control group of the previous; Group (C-s): infected and administered topical chlorhexidine 0.02%; Group (C-c): the control group of the previous and Group (D): a normal control group. The effects of treatment were assessed over 30 days through daily clinical evaluation, grading of AK, parasitological and histopathological examination of corneal tissues. The present work revealed that after inducing keratitis, signs of infection appeared by day 3, and all groups showed similar infection rates before treatment began. Corneal opacity improved significantly in NTZ liquid crystal form- treated group, especially by days 18 to 30, showing outcomes comparable or superior to the chlorhexidine-treated group and markedly better than the NTZ suspension- treated group. Histopathological analysis confirmed these findings, with the NTZ liquid crystal group exhibiting minimal inflammation and no detectable cysts, highlighting its potential as an effective alternative treatment for AK.