Periorbital Subcutaneous Tumor-Like Lesion Due to Dirofilaria repens

Abstract

Dirofilariasis is a zoonotic infection, which is occasionally seen in humans and rarely found as a subcutaneous orbital swelling. The authors report a case of a 62-year-old woman presented with a 3-month history of a right periorbital subcutaneous nodule. Treatment with antibiotics and corticosteroids was not satisfactory. Magnetic resonance imaging analysis showed a nodule with a central colliquative area. The lesion displaced the eyeball superiorly but did not affect the intraorbital muscles. The patient was subjected to excisional biopsy and the nodule measured 15 mm. Histological findings showed microabscess reaction with heterogeneous lymphoid infiltration. Additional consecutive sections finally showed Dirofilaria repens, curled up in spirals with external cuticular ridges in an environment characterized by epithelioid cells. The lesion did not recur for 5 months. Periorbital swelling can be rarely caused by Dirofilaria repens; therefore, this diagnosis should be considered in all cases of subcutaneous inflammatory or tumor-like lesion of unknown etiology.

Human and Animal Dirofilariasis: the Emergence of a Zoonotic Mosaic

“…are traditionally endemic (Italy, France, Greece, and Spain) (302,328), with sporadic reports of small outbreaks of subcutaneous/ocular infections in Germany, the Netherlands, the United Kingdom, and Norway (302). Over the following decade, more cases were reported in Mediterranean countries (5,9,106,128,138,155,160,177,183,201,274,323,325,326,329,331,343,353,357,379,387); at the same time, a series of cases was described in Turkey, Serbia, Croatia, Hungary, and Austria, and sporadic cases occurred in seven other countries (Table 2) (19,20,25,44,54,127,148,209,217,244,341,412,461). In this decade (2000 to 2010), subcutaneous/ocular dirofilariasis expanded from southern to central and northern Europe (149,391,393).…”

A First Human Case of Ocular Dirofilariosis due toDirofilaria repensin Northeastern France

“…Dirofilaria repens is the most frequent human pathogenic nematode species and is encountered almost exclusively in the old world [1–3, 6]. Most cases have been reported in Italy, followed by France and Greece [1–3, 8].…”

“…The natural definitive hosts are dogs and, more rarely, cats [1–3]. The adult female nematode usually lives in the heart or subcutaneous tissues and sheds microfilariae into the bloodstream [2–4].…”

“…Human orbital dirofilariasis is uncommon. Such patients may present with cysts resembling benign or malignant eye tumors [3, 9]. …”

Discrete eyelid swelling caused by live subconjunctival Dirofilaria repens

“…Ocular Dirofilaria repens may have subconjunctival [5][6][7][8], orbital, intravitreal [3,[9][10][11][12][13][14][15][16][17], and subcutaneous locations, such as intrapalpebral locations [5,[18][19][20][21][22] even in the lacrimal gland [23]. The number of cases of ocular filariasis in the Balkans is increasing [3,[24][25][26][27][28].…”