Ocular loiasis affecting a child and its assessment by Anterior Segment Optical Coherence Tomography

Abstract

A 9-year-old girl from Equatorial Guinea presented to the emergency department complaining of foreign body sensation in her right eye. A thin and large, translucent, slowly moving, coiled worm was observed underneath the conjunctiva. Anterior segment optical coherence tomography revealed hyperreflective small areas surrounded by larger hyporeflective areas into the subconjunctival space. Loa loa microfilaria was evidenced on blood test. Surgical extraction of the subconjunctival worm was intended on slit lamp and under sedation in the operating room, but it was unsuccessful due to poor cooperation and rapid migration of the larva into the sub-Tenon’s space. The patient received two cycles of oral albendazole and one cycle of diethylcarbamazine before achieving complete microfilaria seroconversion. Abbreviations: AS-OCT = Anterior Segment Optical Coherence Tomography, PCR = Polymerase Chain Reaction, DEC = diethylcarbamazine.

Case Studies of Severe Microfilaremia in Four Dogs Naturally Infected With Dirofilaria repens as the Primary Disease or a Disease Complicating Factor

“…As reported in lymphatic filariasis, doxycycline treatment against Wolbachia provides clinical improvement in patients with lymphedema (32). It has also been noted in loiasis that high microfilarial loads (30,000-50,000 Mf/ml) can lead to capillary obstruction from damaged parasites after anthelmintic treatment, and adding corticosteroids to the anti-parasitic treatment should be taken into consideration by ESDA and veterinary practitioners in high intensity microfilaremia (22).…”

“…It is certainly possible that the severe microfilaremia might create a blood flow disturbance of capillary circulation by mechanical obstruction. Additionally, it has been observed in other filarial parasitic diseases that dead Mf release toxic products that affect the capillaries (21,22). Unfortunately, the prognosis in taxine alkaloid poisoning without immediate stomach flushing is usually fatal and the presence of subcutaneous dirofilariosis was not likely influential in the course of the intoxication (20), but may be of concern for chronic anemia.…”

Characterising co-infections with Plasmodium spp., Mansonella perstans or Loa loa in asymptomatic children, adults and elderly people living on Bioko Island using nucleic acids extracted from malaria rapid diagnostic tests

“…Between 1978 and 2020, a total of 20 publications described Mansonellosis, Loasis, Onchocerciasis, and lymphatic filariasis in the context of Equatorial Guinea (S1 Table ). Five of these publications described L. loa and M. perstans infections among Equato-Guineans living in Spain [28][29][30][31] or Singapore [32], while three were case reports of foreigners returning from Equatorial Guinea [33][34][35]. One cross-sectional study investigated the prevalence of L. loa and M. perstans on Bioko Island using microscopy and qPCR-based detection [36].…”

Loa loa in the Vitreous Cavity of the Eye: A Case Report and State of Art

“…In a single case report, the use of anterior segment optical coherence tomography as an alternative imaging tool revealed an adult worm in a 9-year-old child from Equatorial Guinea. 24 Similarly, ultrasonography of the right calf (Calabar swelling) revealed a pipeline-shaped lesion suggestive of nematode presence; naked-eye examination was unable to detect it. 25 Furthermore, the blood detection of microfilariae represents one of the main diagnostic tools for the management of loiasis for clinicians to define a proper therapeutic strategy.…”

“…In a single case report, the use of anterior segment optical coherence tomography as an alternative imaging tool revealed an adult worm in a 9-year-old child from Equatorial Guinea. 24 Similarly, ultrasonography of the right calf (Calabar swelling) revealed a pipeline‐shaped lesion suggestive of nematode presence; naked-eye examination was unable to detect it. 25 …”