Acanthamoebic keratitis is usually associated with: March 2011
Ans. D: Soft contact lens users Acanthamoebic keratitis is frequently associated with the wearing of soft contact lenses. Acanthamoeba keratitis It is a rare disease in which amoebae invade the cornea of the eye In developed countries, it is nearly always associated with contact lens use, as Acanthamoeba can survive in the space between the lens and the eye. For this reason, contact lenses must be properly disinfected before wearing, and should be removed when swimming or surfing. However, elsewhere in the world, many cases of Acanthamoeba present in non-contact lens wearers To detect Acanthamoeba on a contact lens in a laboratory, a sheep blood agar plate with a layer (a lawn) of E. coli is made. Pa of the contact lens is placed on the agar plate. If Acanthamoeba are present, they will ingest the bacteria, leaving a clear patch on the plate around the area of the lens. Polymerase chain reaction can also be used to confirm a diagnosis of Acanthamoeba keratitis, especially when contact lenses are not involved. Acanthameoba is also characterized by a brawny edema and hazy view into the interior AC. Late stages of the disease also produces a ring shaped corneal ulcer Signs and symptoms It include severe pain, severe keratitis (similar to stromal herpetic disease), corneal perineuritis, ring ulcer (although this is late in the disease process) Treatment One treatment used is PHMB (poly hexa methyl biguanide). Propamidine isethionate has also shown some effectiveness. Another possible agent is chlorhexidine. Keratoplasty may sometimes be required. A combined regimen of propamidine, miconazole nitrate, and neomycin has also been suggested
Acute dacryocystitis
Ectropion
Xerophthalmia
Soft contact lens users