Clinical findings:
(1) eyelid ptosis
(2) conjunctival hyperemia, chemosis
(3) photophobia
(4) tearing and watering of the eyes
(5) blurred vision
(6) ocular pain
(7) corneal ring
(8) perineural infiltrates
(9) corneal opacities
(10) episcleritis and scleritis
Complications:
(1) accumulation of pus in the anterior chamber (hypopyon)
(2) secondary bacterial infections
(3) hyphema (accumulation of blood in the anterior chamber)
(4) corneal ulceration
(5) bulging of the posterior corneal membrane (Descemet's membrane) through the eroded cornea with rupture and leakage of aqueous humor
(6) chorioretinitis
(7) secondary glaucoma
(8) blindness
Differential diagnosis:
(1) bacterial keratitis
(2) herpes simplex virus keratitis
(3) fungal keratitis
Diagnosis:
(1) chronic corneal infection unresponsive to antibiotic therapy
(2) negative cultures for bacteria, fungus and virus (unless secondarily infected)
(3) corneal scrapings or biopsy positive for cysts or trophozoites on microscopic examination, culture or PCR
Identification of acanthamoeba in a contact lens solution or container is suggestive but not diagnostic since this may occur without infection.
