Imported ocular loaiasis in Jilin Province: a case report

doi:10.12140/j.issn.1000-7423.2026.01.022

Abstract

Abstract:

The patient was a 44-year-old, self-employed, Han ethnic man residing in Dunhua City, Jilin Province. The patient had resided in Gabon, Africa for 5 years due to labor and returned to China in June 2025. On August 9, 2025, the patient visited Yanbian University Hospital with complaints of a foreign body sensation and crawling sensation in the right eye for one day. Routine blood tests showed an eosinophil percentage of 34.7% and an eosinophil count of 3.73 × 10⁹/L. Ophthalmic slit-lamp examinations identified transparent filamentous worms under the conjunctiva of the right eye, exhibiting a wriggling motion, and right eye conjunctival congestion without edema. At approximately 12: 00 on the same day, a subconjunctival parasite extraction was performed under local anesthesia, and the worm, located in the temporal side of the right eye conjunctiva and curled in shape, was completely removed, and identified by the Department Laboratory Medicine of Yanbian University Hospital and Department of Parasitology of Yanbian University Medical College. The worm surface was covered with irregular, smooth, circular, semi-transparent warty protrusions, with sheathed microfilariae in the uterus, and the parasite morphology was consistent with the description of female Loa loa in the literature. The case was diagnosed as imported loaiasis, and postoperatively given antibiotic eye ointment in the conjunctival sac, tobramycin/dexamethasone eye drops and levofloxacin eye drops (one drop each, 4 times daily). Peripheral blood was sampled postoperatively, and no microfilariae were detected in the blood smears by microscopy. A follow-up examination one week post-surgery revealed the patient had self-administered ivermectin tablets (a single oral dose of 150 μg/kg, 2-week treatment course) according to the mass deworming protocol in Gabon. On September 29, 2025, the patient voluntarily visited Beijing Friendship Hospital for a follow-up examination, where L. loa antigen tests yielded a negative result. Albendazole tablets (0.4 g/d) were additionally given, and regular monitoring of blood counts and liver/kidney function was initiated.

Key words: Loaiasis, Ocular, Case report

CLC Number:

R532.15

LU Yan, CUI Jun, ZHOU Fuxian, CUI Renzhe, TIAN Lianji. Imported ocular loaiasis in Jilin Province: a case report[J]. CHINESE JOURNAL OF PARASITOLOGY AND PARASITIC DISEASES, 2026, 44(1): 144-147.

Figures/Tables 2

References 28

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