Thelaziasis - Clinicals, Diagnosis, and Management

Infectious diseases

Clinicals - History

Fact Explanation
Red eye Thelaziasis is a nematode infection of ocular tissue that is caused by Thelazia callipaeda. Human becomes infested after infected flies feed on tears or other lacrimal secretions. The parasite resides in the conjunctival sac, and lacrimal gland and canal. This causes in an inflammation of the conjunctiva which is characterized by redness in the white of the eye or inner eyelid, increased amount of tears, burning or itching sensation of the eyes. Patients may complain of a foreign body sensation. The disease usually involves one eye. Red eye
Thelaziasis is a nematode infection of ocular tissue that is caused by Thelazia callipaeda. Human becomes infested after infected flies feed on tears or other lacrimal secretions. The parasite resides in the conjunctival sac, and lacrimal gland and canal. This causes in an inflammation of the conjunctiva which is characterized by redness in the white of the eye or inner eyelid, increased amount of tears, burning or itching sensation of the eyes. Patients may complain of a foreign body sensation. The disease usually involves one eye.
Visual disturbances In severe infections, patients may present with blurring of the vision, photophobia or blindness. Visual disturbances
In severe infections, patients may present with blurring of the vision, photophobia or blindness.
At risk population Thelaziasis occurs worldwide. But it is more common in regions like United States, China, Russia, India, Japan, and Thailand. At risk population
Thelaziasis occurs worldwide. But it is more common in regions like United States, China, Russia, India, Japan, and Thailand.

Clinicals - Examination

Fact Explanation
Conjunctivitis Infestation of the eyes results in inflammation of the conjunctiva. This is characterized by redness in the conjunctiva, epiphora and greenish/ yellowish/ whitish eye discharge. Conjunctivitis
Infestation of the eyes results in inflammation of the conjunctiva. This is characterized by redness in the conjunctiva, epiphora and greenish/ yellowish/ whitish eye discharge.
Corneal changes In severe disease the parasite can migrate to the cornea from the conjunctivae causing corneal opacity, or corneal ulcers (ulcerative keratitis) Corneal changes
In severe disease the parasite can migrate to the cornea from the conjunctivae causing corneal opacity, or corneal ulcers (ulcerative keratitis)
Visual disturbances Vision examination will reveal blurring of vision to blindness. Visual disturbances
Vision examination will reveal blurring of vision to blindness.
Worm The conjunctival examination may show the parasite in the conjunctival sac. Adult worm may measure up to 2.0 cm in length. Worm
The conjunctival examination may show the parasite in the conjunctival sac. Adult worm may measure up to 2.0 cm in length.

Investigations - Diagnosis

Fact Explanation
Microscopic examination After finding the adult worm in the conjunctival sac, worms has to be removed with forceps. The parasite is examined under the microscopy for the confirmation of the diagnosis. Its cuticle has coarse striations, often giving the worms a serrate appearance. The mouth is without lips and the esophagus is short. The tail of the male is recurved and without caudal alae. The tail of the female is bluntly rounded. Microscopic examination
After finding the adult worm in the conjunctival sac, worms has to be removed with forceps. The parasite is examined under the microscopy for the confirmation of the diagnosis. Its cuticle has coarse striations, often giving the worms a serrate appearance. The mouth is without lips and the esophagus is short. The tail of the male is recurved and without caudal alae. The tail of the female is bluntly rounded.

Management - Supportive

Fact Explanation
Prevention Thelaziasis can be prevented by controlling of the fly vector by use of bed nets to protect children while they are sleeping and by keeping their faces and eyes clean. Prevention
Thelaziasis can be prevented by controlling of the fly vector by use of bed nets to protect children while they are sleeping and by keeping their faces and eyes clean.

Management - Specific

Fact Explanation
Physical extraction of the adult worm This is the only definitive treatment in human. The adult worm is removed from the conjunctival sac using topical anesthesia and antibiotic eye drops. Physical extraction of the adult worm
This is the only definitive treatment in human. The adult worm is removed from the conjunctival sac using topical anesthesia and antibiotic eye drops.

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