A picture speaks a thousand words: A case of ocular Loa loa

Abstract

The ‘African eye worm’, also known as Loa loa, is filarial nematode that is commonly, transmitted by deer flies. A history of recent travel to endemic countries near western, Africa is common in patients with Loiasis. While a majority of patients infected with Loa, loa are asymptomatic, common presentations of Loiasis include localized areas of, edema, Calbar swellings, and ocular symptoms secondary to the migration of worms, through the spaces within the eye. This case illustrated presents a healthy 31-year-old, man with no history of recent travel who presented after his friend reported that a worm, was seen in his right eye., The patient had described symptoms of pain, redness, and excessive lacrimation in his, right eye for the past five days. Although the patient originally lived in Cameroon, he, had not travelled there or to any other country since arriving to the United Arab, Emirates two years ago. On physical examination, a worm was not visualized in his, eye. However, a personal photograph of the patient taken two days prior was provided, showcasing a long thin worm migrating in the lateral subconjunctival space of his right, eye. Laboratory investigations revealed eosinophilia in this patient. The personal, photograph along with these findings allowed for the diagnosis of Loiasis, and the, patient recovered completely following an extended 42-day course of oral albendazole., This case highlights the importance of a patient’s history and the physical evidence, they bring with them, especially in patients with ambiguous physical findings and, laboratory results

Loa loa is a filarial nematode that is commonly known as the ‘African eye worm’, and it is commonly endemic to West Central Africa [1]. Deer flies from the genus Chrysops, such as C. dimidiata and C. silacea, are the main vector of transmission for Loa loa [2]. Although most patients with loiasis are asymptomatic, symptomatic patients commonly present with characteristic Calabar swellings, which are restricted areas of edema caused by migrating Loa loa worms. Another classic manifestation of loiasis is the presence of visible adult worms migrating within the subconjunctival space of the eye [3].

We present a 31-year-old man with no medical history who came into the clinic because his friend saw a worm in his right eye two days ago. The patient felt something moving in his eye four days ago but ignored it due to his busy work schedule. The patient had been experiencing pain, redness, and excessive lacrimation in his right eye for the past five days. They denied any changes in his vision or discharge from his right eye. The patient was born in Cameroon and lived there for most of his life until coming to the United Arab Emirates two years ago. They denied any recent travel. A review of systems was negative for fever, skin changes, joint pain, or swellings.

On physical examination of this patient, his right eye had mild conjunctival injection and chemosis. No obvious worm or foreign body was appreciated in his right eye, however. Left eye examination was completely normal. The rest of his physical examination was unremarkable. The patient provided a personal photograph of his right eye taken two days ago, showing a long threadlike worm moving in the lateral subconjunctival space of his right eye (Fig. 1). Lab investigations including a complete blood count, C-reactive protein levels, and a basic metabolic panel were ordered, and the only abnormal laboratory result was eosinophilia at 2.12 × 10⁹/L (differential eosinophil count 28.4 %).

Fig. 1.

Patient’s personal photograph: Loa loa in the lateral subconjunctival space of the right eye.

The personal photo of his right eye along with the patient’s history, examination, and eosinophilia allowed for the clinical diagnosis of Loiasis to be made for this patient. Since diethylcarbamazine was unavailable, treatment with oral albendazole (200 mg twice a day) was started for 21 days [4]. After the treatment course, the redness and itching of his right eye had improved but was still present. A 21-day course of oral albendazole was given again, and the patient recovered fully following completion.

Consent

Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

CRediT authorship contribution statement

Sukaina Dawood Jaafar: Writing – review & editing. Rayan Tareg Ahmed: Writing – review & editing. Hazem Abdalla: Writing – review & editing. Waqar Gaba: Writing – review & editing. Mohammed ElKhazendar: Writing – review & editing. Ahmad Abdalla: Writing – original draft.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.