The Diagnosis And Treatment Of Microsporidial Keratitis: A Case Series

To record the diagnosis and treament of microsporidial keratitis in a case series.

Five cases were referred to our medical center, after treatment as bacterial keratitis in lcoal medicial clinic for weeks. This is a presentation of case series.

When aprroaching, contact history was recorded. Corneal scraping smear with Gram's stain, KOH and Acid-fast stain were performed. Empiric diagnosis was made according to smear result and keratitis pattern. Combined treatment with 0.02% Chlorhexidine (CHG), 0.02% Polyhexamethylene Biguanide (PHMB) and anti-fungal agents was prescribed. Therapeutic keratoplasty was done once lesion was progressive, and the sacrificed cornea was sent for pathology and electic microscopic examination.  

Seven eyes of 5 patients were enrolled. Five of 7 eyes were stromal keraitis, and the other 2 were dot epitheliitis. Farm work is the most common conatct history. Corneal scraping smear with KOH showed round or oval shpaed spores. Stromal involvement is the poor prognosis sign. Four of 5 stromal keratitis  (80%) needs therapeutic keratoplasty, in which, 3 were penetrating keratoplasty and 1 was anterior lamellar keratoplasty.  The anterior lamellar keratoplasty was performed with porcine cornea tissue in a clinical trial. One graft was primary failure, and one was acute melting. Pathology with PAS and Acid-fast stain showed much intra-stromal spores. And the electric microspe could reveal different life cycle stages of microsporidia.

Microspordial keratitis is a vision threatening corneal infection. Stromal involvement is a poor prognostic factor, whih results in therapeutic keratoplasty for 80%. Combined treatment with PHMB, CHG and anti-fungal agents were usually needed. Electric microscope can reveal different life cycle stages of microsporidia.