Jpn. J. Infect. Dis., 55, 47148, 2002

Short Communication

Subconjunctival Infection with Dirojilaria repens
Ⅵkas Gautam*, I, M. Rustagil, Satyavir Singh2 and D. R. Arora

Department ofMicrobioloBy andJDepartment of Ophthalmology, Postgraduate Institute ofMedical Sciences, Rohtak and2Departm ent ofParasitolobT,
Choudhayy Charan Singh Hisar Agricultural UniversiO?, Hisar, India(Received February 14, 2002, Accepted March 1 8, 2002)
SUMMARY: Cases ofzoonotic dirofilariasis infection, caused by Diroj言Iaria repens, Occur widely throughout
European, A舟ican, Middle Eastem, andAsian countries. The reports of this infection in humans in India arelimited, and we herein report the case of a 23‑year‑old man who presented with subconJunCtival swelling in theright eye with no local symptoms. A large nematode was visualized on examination and the intact worm wassurgically removed. The parasite was identified as a male D. repens.

A 23‑year‑old man presented with a 20‑day‑old history ofswelling in theright eye, His medical history showed no otherCulex spp.(1). Review ofworld literature showsthat 397 casesof human subcutaneous dirofllariasis caused by D. repens werecomplaints or any serious general health problems. The patient

recorded舟om 30 Countries with endemic fわci in Southem

was a farmer by occupation and reported close associationand Eastem Europe, Asia Minor, Cen廿al Asia, and Sri Lanka

with domestic animals. He had no history oftravelling abroad.

(2). However, the reports of this ocular infection in India are

On ocular ex.amination, his visual acuitywPs BE, 20/20･

limited with the first report in the year 2000 by Sekhar et al.

Slit‑lamp examlnation disclosed a white, movlng nematOde(3,4). To ourknowledgethis isthe third such case report &om

that was coiled and located under the bulbar conJunCtiva ofIndia. Cases of subcutaneous dirofilariasis were orlglnallythe right eye, about 1.2 cm from the limbus and in thecalled Dirojilaria conjunctivae because many of them localized

inferotemporal quadrant at the 4 0'clock meridian. A uniform,

inand aroundthe eye and eyelids (5). D. repens is also believed

avascular swelling of5 × 5 mm in the lateral canthal bulbar

to be synonymouswith D, tenuis, which is endemic to theUnited States and is carried by raccoons. In humans, D. repens
is the cause oflocal subcutaneous dirofilariasis and must be

conJunCtiva of right eye was present. The conJunCtiva over

the worm was only slightly elevated and not Injected. The

difFerentiated from D. immitis, which causes microfllaremia
and requires the use of anthelminthic agents. D. repens

remainder of the anterior and posterior segment examination

was unremarkable, The left eye was normal.

displays longitudinalridges, where D, immitis has a smooth

Under local anesthesia, the conJunCtiva was incised overthe site where the nematode was located. The live intact

cuticle, allowing the diagnosis of the species on a morph0‑

nematode performing Peristaltic movements was grasped andlogical basis (6).

removed (Figs･ 1A, B), and preseTed in lO% formaldehyde

Dirofilariasis should be consideredinthe differential dia即0‑

for identification, The conJunCtlVa Was Closed with 8‑0

sis oflesions initiallyinterpreted as malignant or benign tumors.
Human cases ofdirofilariasis are most probably underreportedabsorbable sutures.

The nematode was thin, cylindrical, and white with coiled

because many of them remain undiagnosed orunpublishedends. The won was stretched and measllred 8.3 cm long(3,7)･ The syrgical removal of the lesion not only establishes
the diagnosis in most cases but also presents a definite cure.

and 0,5 mm thick (Fig. 1C). The anterior end was bluntly
rounded having a small mouth without buccal capsule (Fig.

lD). The cuticle of the worm, extending komtheanterior end

ACKN OWLED GMENTS

to the tail, had marked longitudinal ridges with transverse

striations (Fig. 1E). The posterior end was slightly curved

Thanks are due to Dr. R. Sehgal (Additional Professor),

having papillae and unequal spICuleswith distinct caudal alae

Dr. H.S. Bhatti (Lecturer), and Dr, Kavya Mohandas (Senior(Fig. 1F). The above features indicated that it was a maleResident) of Department of Parasitology, Postgraduate InstituteDirojilaria repens. As expected, the patient's blood testofMedical Education and Research, Chandigarh, India, forresults did not showmicrofllariae because thistype of filariarendering their help.

usually remains subcutaneous or submucosal at the point of

the bite of an insect vector, Routine laboratory tests wereREFERENCES

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E‑mail: r̲vg@yahoo.co.uk

47Fig･ 1A: DirojiJaria repens adult worm rolling out ofsubconjunctiva (shownwith arrow)A B: D･ repens grasped and removed
舟om the subconjunctiva. C: Photograph ofD, repens as removed舟om the subconJunCtiva. D: Photomicrograph of anterior

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