Ophthalmomyiasis Externa: Case Report of the Clinicopathologic Features

Ophthalmomyiasis Externa and Importance of Risk Factors, Clinical Manifestations, and Diagnosis: Review of the Medical Literature

OBJECTIVE

This review aims to describe and compare the risk factors, clinical course, diagnosis, and parasitologic features of external ophthalmomyiasis. We also discuss the different preventive measures and the effect of global warming in a large case series reported from January 2000 to December 2022.

METHODS

We perform a literature review of reported cases of external ophthalmomyiasis to determine the clinical characteristics, therapeutic management, and information on the organisms that most commonly cause external ophthalmomyiasis.

RESULTS

A total of 312 cases of external ophthalmomyiasis were recorded. The most common causative organism was Oestrus ovis (Linnaeus) (Diptera: Oestridae), accounting for 72.1% of cases, followed by Dermatobia hominis (Linnaeus Jr. in Pallas, 1781) (Diptera: Oestridae) at 5.4%, Lucilia sericata (Meigen) (Diptera: Calliphoridae) at 0.96%, and Chrysomyia bezziana (Villeneuve) (Diptera: Calliphoridae) at 0.96%. Before experiencing symptoms, 43.6% of cases reported having direct contact with flies or being hit in the eye, 33% reported no associated risk factors, 9.3% reported living with sheep and goats, and 7.7% reported a history of foreign objects entering the eye. The most common symptoms for those affected by O. ovis were sudden onset, including a foreign body sensation and movement, redness, tearing, itching, swelling, irritation, photophobia, burning, and ocular secretion. In cases caused by D. hominis, symptoms included eyelid edema, pain, redness, itching, movement within the lesion, ocular irritation, and discharge. Regarding occupational or recreational activity, agriculture, and livestock had the highest incidence, followed by trades and technical activities, being a student, and having traveled to an endemic region for work or recreation.

CONCLUSION

Patients with red eyes may suffer from external ophthalmomyiasis, which requires a thorough examination to diagnose and treat it early. Moreover, as the temperature increases due to climate change, it is essential to consider how this will affect the spread of different pathogens.

Ophthalmomyiasis externa: A case report

Ophthalmomyiasis is the infestation of ocular structures by fly larvae (maggots). Oestrus ovis is common among them. This is usually observed in rural areas, but a case presented here is from the urban areas. Depending on the species of larvae and ocular structure involved, manifestations vary from self-limiting condition to optic nerve involvement which may lead to blindness, and hence, identification and prompt management is necessary. This case report alerts the ophthalmologists from the urban areas to consider time management and also microbiologists for rapid identification.

EXTERNAL OPHTHALMOMYIASIS CAUSED BY OESTRUS OVIS (A CASE REPORT)

The work deals with atypical conjunctival infection of Czech patient with Oestrus ovis larvae. Ophthalmomyiasis is infestation of mammalian eyes by the larvae or worms of some flies. The most common cause of human myiasis is the Sheep. Shepherds are infected in habitats, but human eye disease outside the areas of abundant hamsters is rare. We describe a case of eye disease in a middle-aged man from the Czech Republic who spent a summer holiday seven weeks before examination in the north of Greece. During the first examination he was completely treated and no further problems were reported. Ophthalmomyiasis externa should be considered as a possible infection of travelers to the southern endemic regions when returning with an acute causeless onset of a one-sided foreign body sensation in the eye.

A Case and Review of Ophthalmomyiasis Caused by Oestrus ovis in the Central Valley of California, United States

Ophthalmomyiasis externa is the infestation of external ocular structures most commonly by Oestrus ovis, sheep nasal bot fly, which have a pupal stage in soil. Farmers and shepherds are commonly affected but rarely in urban areas. This is the first case of Oestrus ovis ophthalmomyiasis externa in California since Catalina Island 1986. No livestock exposure was noted. Manure fertilizer sourced from grazing fields of natural hosts was used on a local urban sports field and is the suspected source.

A case of ophthalmomyiasis interna in the Pacific Northwest

PURPOSE

We report a case of ophthalmomyiasis interna successfully removed in toto with pars plana vitrectomy.

OBSERVATIONS

An 84-year-old woman with recent close contact with lambs presented with a new floater. Examination revealed subretinal tracks pathognomonic for ophthalmomyiasis and a larva suspended in the vitreous. The larva was successfully removed in toto with pars plana vitrectomy by aspiration through the vitreous cutter.

CONCLUSIONS AND IMPORTANCE

Aspiration with pars plana vitrectomy can be considered a primary therapeutic modality for botfly larvae suspended in the vitreous. In our case, in toto removal of the larvae reduced the risk of inflammatory reaction.

External ophthalmomyiasis: a case series and review of ophthalmomyiasis in Turkey

Ophthalmomyiasis externa is the infestation of the superficial external ocular structures by fly larvae. This is a particularly rare condition, which has nevertheless been reported in several countries worldwide. It is common in sheep-farming areas, especially in Mediterranean countries. The patients may present with classic conjunctivitis, pseudomembranous conjunctivitis, conjunctival hemorrhages, punctuate keratitis, keratouveitis, and eyelid edema with erythema. Herein, we present three cases of external ophthalmomyiasis caused by Oestrus ovis larvae and review ophthalmomyiasis cases reported from Turkey.

Diagnosis of ophthalmomyiasis externa by dermatoscopy

Ophthalmomyiasis in humans caused by the larvae of the sheep nasal botfly (Oestrus ovis) and is a rare phenomenon in Israel. We describe the utilization of the dermatoscope as a diagnostic tool for the facilitation of early diagnosis of conjunctivitis due to the infestation of the eyes by the sheep nasal botfly in two patients. After the physical removal of the larvae with the help of a cotton swab applicator under a slit lamp examination and the topical use of antibiotics, the clinical symptoms improved within 1-2 days. Undoubtedly the dermatoscope played a crucial role leading to the definitive diagnosis and immediate therapeutic intervention.

Ophthalmomyiasis externa: three cases caused by Oestrus ovis larvae in Turkey

Ocular involvement of parasitic infections includes external, internal and orbital ophthalmomyiasis. Oestrus ovis (sheep botfly) is the most common cause of ophthalmomyiasis externa. Living in warm climates, particularly in agricultural districts, is a risk factor. Although external ophthalmomyiasis can be treated by removal of the infecting larva(e) and topical drug treatment, the risk remains of its presence leading to further contamination for other people. We describe three cases of external ophthalmomyiasis due to infestation with the first instar larvae of O. ovis An awareness of larval conjunctivitis in endemic areas may avoid misdiagnosis and allow immediate management to prevent complications.