Live Wuchereria bancrofti in anterior chamber of the eye: A case report

We are reporting a case of live filarial worm in the anterior chamber (AC), with in toto removal for microbiological evaluation without damaging the ocular structures. A 34-year-old male presented with sudden-onset redness in the left eye for 4 days, associated with irritation and photophobia. On examination, his best corrected visual acuity was 6/6, with circumcorneal congestion. Slit-lamp examination of the AC showed cells and flare, along with a long translucent thin motile worm, with wriggling movement. Iris showed a thin, irregular, white atrophic patch nasally through which the worm had entered the AC. The worm was isolated surgically from AC in toto with the forceps, assisted by intracameral pilocarpine and viscoelastics. Microbiological examination of the worm by a parasitologist was suggestive of a growing adult male Wuchereria bancrofti.

Keywords: Anterior chamber, eye, filarial worm, Wuchereria bancrofti

How to cite this article:
Khokhar S, Patil B, Sharma R, Sinha G, Gupta S, Kakkar P, Nayak B, Mirdha BR. Live Wuchereria bancrofti in anterior chamber of the eye: A case report. Trop J Med Res 2015;18:45-7

How to cite this URL:
Khokhar S, Patil B, Sharma R, Sinha G, Gupta S, Kakkar P, Nayak B, Mirdha BR. Live Wuchereria bancrofti in anterior chamber of the eye: A case report. Trop J Med Res [serial online] 2015 [cited 2016 Apr 15];18:45-7. Available from:

Filariasis is an important public health problem in India, where about a third of the global population lives at risk of this disease. [1] This vector-borne parasitic disease is caused mainly by two nematode parasites, Wuchereria bancrofti and Brugia malayi. Filariasis is mainly a disease of the lymphatic system. However, rarely it can present as intraocular filariasis in an otherwise asymptomatic patient without any constitutional symptoms.

Nematode identification at the species level might be supported by anamnestic information, such as host and geographic location. However, for reliable, definitive, species identification, proper morphologic or molecular diagnosis is needed. We are reporting a case of removal of live filarial worm from the anterior chamber (AC) of the eye without damaging any ocular structure, which was subsequently sent to a parasitologist for microscopic examination.

A 34-year-old male presented with sudden-onset redness in his left eye for 4 days, associated with irritation and photophobia. Systemic history for any disease including gastrointestinal and skin diseases was negative. Patient had a history of having worked near the coastal regions of Maharashtra (Mumbai) for about 4 years before he came to Delhi 1½ years back. His ocular examination showed a visual acuity of 6/6 in both eyes. Mild conjunctival and circumcorneal congestion was noted in the left eye. AC of the left eye showed a normal depth with 2+ cells and flare, along with the presence of a long, translucent, thin motile worm, wriggling within the AC [Figure 1]a and [Figure 1]b. Iris showed a thin, irregular, white atrophic patch nasally [Figure 1]a, presumably through which the worm had entered the AC. His pupillary reactions were within normal limits. The conjunctival fornices and the cornea were normal. Ocular movements, intraocular pressure fundoscopy, and ultrasound biomicroscopy (UBM) of both eyes were normal.
Figure 1: (a and b) Long, translucent, thin motile worm within the anterior chamber. (c) Coiling of the worm (arrow mark) on injection of intracameral pilocarpine. (d) Removal of live worm from the incision site

A provisional diagnosis of iridocyclitis with a live intraocular parasite, most probably bancroftian filariasis, was made. Patient was started on topical steroids, cycloplegic, and antibiotics. Surgical extraction of the worm was planned under local anesthesia. Peripheral blood sample was negative for microfilaria on quantitative buffy coat (QBC) assay, and stool was negative for cysts and ova of parasites. Patient had 7% eosinophilia and W. bancrofti Og4C3 antigen was positive on immunochromatography (Binax Now Filariasis; Alere, Brisbane, Queensland, Australia).

After peribulbar anesthesia and proper aseptic precaution, a side port was made at 9 O’clock nasally. Pilocarpine (0.25%) was injected for constriction of the pupil to prevent migration of the worm into the posterior chamber. Pilocarpine (0.25%) with an acidic pH irritated the worm and made it to coil on itself [[Figure 1]c, Video 1]. The worm got stuck at the incision as it came out, where it was picked up by the forceps [[Figure 1]d, Video 1] by restricting its motility using 2% Hydroxy propyl methyl cellulose (HPMC) over it. The live worm was put in saline 0.9% and was sent to the microbiology department for evaluation by a parasitologist (video with arrow mark).

Morphological examination showed a white, cylindrical, thread-like worm, with both ends tapering. On microscopy, it had a translucent, smooth external cuticle and was devoid of any chitinous exoskeleton. Blunt rounded head end [Figure 2]a and pointed tail end [Figure 2]b with two spicule-like structures were visible. It was unsegmented without any appendage [Figure 2]c and [Figure 2]d. Structures suggestive of double tract reproductive tube were not seen. On micrometry, the worm had a length of 9 mm and a breadth of 0.08 mm, which identified it as a growing adult male W. bancrofti.
Figure 2: (a) Blunt, rounded head of the worm. (b) Pointed tail end of the worm. (c and d) Unsegmented worm without any appendages

Postoperatively, the patient was given topical steroids and antibiotics, and oral therapy with diethylcarbamazine (6 mg/kg/day for 2-3 weeks) was started. At the time of discharge, patient had a vision of 6/6 both eyes, with few cells in his left eye.

Intraocular filariasis is caused more commonly by microfilariae than by adult worms. [2] Uveitis secondary to intraocular filariasis in the Indian subcontinent is mainly due to W. bancrofti and B. malayi. [3] There are limited reports of removal of live filarial worm from the intraocular structure. [2],[3],[4],[5],[6]

W. bancrofti is a helminth belonging to class Nematodes. Man is the definitive host, the intermediate host being species of Anopheles mosquitoes. Adult worms live in the lymphatic system, discharging live embryos (microfilaria) into the bloodstream. Adult filarial worms are thread-like structures that live in the subcutaneous tissues and the lymphatic system. They sexually reproduce microfilaria, the first larval stage. Microfilariae are ingested by hematophagus arthropods, where they develop into infective larvae that grow in the vertebrate host and mature into adult worms. The exact route of invasion of microfilaria into the eye is still unknown. Probably, they enter the eye through the long and short posterior ciliary vessels, cerebrospinal fluid, or the optic nerve sheath. [7]

The first recorded case of an intraocular filaria was published by Mercier in 1771. Intraocular parasitism by different species of adult filarial worm has been reported in the literature. Wright [8] and Nayar and Pillai [9] reported intraocular adult worms of Wuchereria species. They found a paramacular chorioretinal defect from which the worm had emerged into the AC. Nayar’s case was followed over a 4-week period as the worm changed from a larval to a juvenile form during its migration from the posterior vitreous to the AC. Fernando [10] and Chatterji [11] reported adult W. bancrofti worm in the AC; however, the point of intraocular penetration was not discovered. Mishra reported an adult intravitreal worm, provisionally W. bancrofti, that broke free from the paramacular choroid and retina. [12] Rose reported an unproven case of B. malayi adult worm in the AC of the eye of a man in Malaysia. [13] Dissanaike et al. reported a case of human eye infection caused by adult worm of B. malayi in Malaysia. [14] Osuntokun and Olurin reported two cases of adult Loa loa in the AC of the eye. [15] Joseph and Raju reported a case of iritis caused by immature W. bancrofti. [16] They were able to extract the organism for morphological examination. Carme et al. observed and removed an adult L. loa worm from the AC of a 60-year-old woman. [17] Arora and Das reported a case of live male adult W. bancrofti in the AC that disappeared after intense AC reaction. [3] They hypothesized that either it was lysed (as can be explained on the basis of the AC reaction to the worm proteins) or it had taken a route out of the eye. Samarsinghe and Pathirana observed a live worm in the vitreous cavity, extracted it, and found it to be female W. bancrofti on microbiological examination. [18] Eballe et al. reported a case of living adult L. loa worm in an 8-year-old child, which was removed under general anesthesia. [19] Rao et al. reported intravitreal live adult Brugian filariasis from Orissa, India. [6]

Presumably, this particular worm came to the iris tissue through ciliary vasculature, and was lodged there, where it developed and attained a length of 9 mm. Had it not been removed, it would have caused damage to the iris and surrounding tissues. In all the previous cases that have been reported in literature, the surgeons were not able to isolate the worm in a living state without causing any damage to the ocular structures. We were able to remove the whole worm alive in toto without damaging any ocular structure, thus preserving the vision.

We want to stress that in the tropics where filariasis is endemic, it may be worthwhile to rule out filariasis in all cases of uveitis of obscure etiology. To prevent the occurrence of ocular filariasis, global/national programs are needed, especially in endemic areas, for elimination of the most common form of filariasis, that is, lymphatic filariasis.