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A 59-year-old female living in Rayong Province, eastern Thailand, presented with painless, right upper eyelid nodule for 3 months. Upon removal of the eyelid mass, a well-circumscribed, firm globular mass with diameter about 1 cm was found. Histopathological examination revealed an immature female dirofilarial worm reminiscent of Dirofilaria repens, characterized by prominent sharp longitudinal ridges at external surface of the cuticle. Analysis of the mitochondrial 12S rRNA sequence showed that the worm belongs to Candidatus Dirofilaria hongkongensis. It is likely that some infections previously reported as D. repens based on histological examination may have actually been due to Candidatus D. hongkongensis.
Disclaimer: All authors have no conflicts of interest to declare and all have actively contributed to this report.
Authors’ addresses: Suppapong Tirakunwichcha, Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, E-mail: suppapong@gmail.com. Lalana Sansopha, Department of Pathology, Faculty of Medicine, Chulalongkorn University; Bangkok, Thailand, E-mail: lalanasansopha@gmail.com. Chaturong Putaporntip and Somchai Jongwutiwes, Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, E-mails: p.chaturong@gmail.com and jongwutiwes@gmail.com.