Int J Med Health Sci. July 2014,Vol-3;Issue-3 223 International Journal of Medical and Health Sciences Journal Home Page: http://www.ijmhs.net ISSN:2277-4505 Discussion of a case of Dirofilariasis presenting as a nodular mass Preeja Premakumar 1 , Vivek Velayudhan Nair 2* , Bindu Janardanan Nair 3 , Sunila Thomas 4 , Vineet Daniel Alex 5 , Jincy Thomas 6 , Rani Mol Prasanna 7 1 Post graduate student, 2 Professor & Head, 4 Professor, 5 Reader, 6&7 Senior Lecturers, Department of Oral Medicine and Radiology, 3 Professor & Head, Department of Oral Pathology and Microbiology, PMS College of Dental science & Research, Golden Hills, Vattappara,Venkode PO, Trivandrum, Pin 695028, Kerala, India. ABSTRACT Human Dirofilariasis is a zoonotic disease which presents commonly as subcutaneous nodules. They are considered as emerging pathogens, as the frequencies of reports are increasing in literature over the last few years. These lesions closely have a wide variety of differential diagnosis and resemble several benign and malignant tumors, it is important to consider this as a differential diagnosis in a case of subcutaneous nodule especially in an endemic area or in coastal population. This article attempts to discuss the differential diagnosis of a case of a facial subcutaneous nodular mass palpable intraorally finally diagnosed as Dirofilariasis in an endemic area in Trivandrum, Kerala. KEYWORDS: Dirofilariasis, Endemic, Nodular mass. INTRODUCTION Dirofilariasis is a zoonotic infection which is caused by Dirofilaria immitis, Dirofilaria repens, Dirofilaria tenius and Dirofilaria ursi. It is transmitted to humans by Culex, Aedes or the Anopheles mosquitoes which ingest the blood containing Microfilaria from affected animals [1]. This infection rarely affects oral mucosa. Lesions are presented as single non tender subcutaneous/submucosal nodules and most patients are asymptomatic [2]. The reported cases from India are limited and most of the published cases are of ocular dirofilariasis, occurring in an endemic areas or in coastal population. A case of firm non tender nodular intraoral swelling, finally diagnosed as dirofilariasis is presented with emphasis on differential diagnosis. CASE REPORT A 32 year old male from Trivandrum, Kerala, South India presented with non tender diffuse swelling on the right cheek, more towards the lower jaw, of one month duration. The swelling was slow growing (Figure 1). The patient gave a history of a similar swelling which disappeared without treatment in the same location six months previously. The past medical history was non contributory. The swelling could not be appreciated intraorally by visual examination alone (Figure 2). On palpation a firm non tender swelling measuring approximately 2x2 cm could be appreciated on the right buccal sulcus apical to 45, 46 and 47 with ill- defined edges. The overlying mucosa did not show any change of colour or local rise of temperature. Patient had a partially erupted 48 with deep periodontal pocket distal to 47. All the teeth in the lower right quadrant were caries free and tested positive to electrical pulp tester. Intraoral periapical radiograph showed normal periodontal ligament space, lamina dura and trabecular pattern in 45, 46, 47 region. Panoramic radiographic picture was normal except for mesioangular impaction of 48 and a large radiolucency in the crown of 38 (Figure 3). The results of routine blood investigations were all within normal limits. Thus a provisional differential diagnosis list of which included Dirofilariasis was finalised. An excisional biopsy under local anesthesia was planned since the lesion was freely movable and there was no evidence of induration or invasion of surrounding structures. The specimen was sent to the Department of Oral and Maxillofacial Pathology for histopathological evaluation. Case Report