Crab lice infestation in unilateral eyelashes and adjacent eyelids: A case report

BACKGROUND: Crab lice (Phthirus pubis) infestation can occur at any age, to either males or females, and across all regions of the world. However, cases involving the eyelashes and adjacent eyelids (phthiriasis palpebrarum) are rare. Usually occurring as a sexually transmitted disease, crab lice can be spread by poor hygiene or in a dirty environment through direct contact with contaminated skin (hands) or textiles (towels and clothing). CASE SUMMARY: A 50-year-old woman presented to our hospital with a 2-wk history of chronic eyelid pain and itching in the right eye, which exacerbated in the evening hours and which had not resolved following a 1-wk course of antibiotics and corticosteroid ointments (for blepharitis diagnosis from another hospital). A careful ophthalmic slit-lamp and light microscope examination revealed multiple crab lice and nits on the right upper eyelashes; the right and left lower eyelashes were normal. Following the new diagnosis of phthiriasis palpebrarum, the patient was treated by removing the affected eyelashes, the crab lice, and their nits completely. Additionally, the eyelids were washed once with povidone-iodine. A follow-up examination at 2 wk later showed complete resolution of symptoms and no evidence of re-infection. CONCLUSION: This case emphasizes the importance of correct diagnosis and complete removal of eyelashes, crab lice and nits to cure phthiriasis palpebrarum.