These infections are difficult to recognize and treat, and the outcome of all reported cases has been very poor. Although they have characteristic features, such as a slow relapsing course with development of ring abscess, recurrent opithelial breakdown, hypopyon which waxes and wanes, and secondary glaucoma, diagnosis is difficult because the organism cannot be identified on the usual corneal scrapings and smears which are taken and air dried to fix cells and bacteria. Such air drying causes rupture of these delicate organisms, leaving no distinctive residuum, but preserves cysts where present. Special culture plates of plain agar preseeded with aerobacter or E. coli to encourage growth of Acanthamoeba are needed. Too often, Acanthamoebae are considered only after conventional treatment for more common causes of suppurative keratitis has failed.
Treatment is difficult because most antibiotics are ineffective.
This incident occurred in April 1979. The infection which insued was treated with various topical medicaments by the patient's general practitioner and local ophthalmologist until June, when the patient was referred to Moorfields Eye Hospital, London. Treatment continued but by September the corneal epithelium had broken down, with increasing stromal supporation and hypopyon, producing an appearance similar to that seen in another patient known to have had acanthamoeba infections. Smears continued to show only pus cells and debris with no organisms. Special cultures from both cornea and conjuctiva grew Acanthamoeba, permitting their positive identification.