A mixed infection of bacteria with a large number of amoebas could also have contributed to the abrupt development of endogenous endophthalmitis in this patient. The rapid invasion of amoebas into the vitreous fluid and aqueous humor in this patient is in marked contrast with the chronic and slow-growing amoebic infection of the cornea. This may be attributable to anatomical differences in the tissues and also to the difference in routes of infection. An abrupt course is also common in amoebic meningoencephalitis. It should be noted that the patient was not in an immunocompromised condition, such as with diabetes mellitus or drug abuse.
Amoebic meningoencephalitis can occur in healthy patients.
The patient recovered his vision after the emergency vitrectomy with irrigation containing antibiotic and antifungal agents. The white retinal lesions around the optic disc also disappeared after a 2-week course of the combined use of antibiotic and antifungal agents. In contrast with the difficulty in managing an Acanthamoeba corneal infection, this positive outcome to antifungal treatment might be attributable to the retinal vascular supply and preceding vitrectomy. Cytological examinations of the aqueous and vitreous are important in the detection of unusual causes of endogenous endophthalmitis, such as amoebas. Accepted for publication June 16, 2000.