Subcutaneous nodule: A case of Dirofilaria
A 28-year-old male hailing from Cochin, South India presented with a subcutaneous nodule on the left cheek of duration of 2 weeks, which was gradually increasing. On clinical examination, he had a firm oval swelling on the left cheek measuring 1.5 cm × 1 cm, which was non-tender and freely mobile. The systemic examination was unremarkable. A clinical diagnosis of a subcutaneous swelling/Sebaceous cyst was made, and the swelling was excised as an out-patient procedure under local anaesthesia. On excision two live thread like cylindrical worms, 0.5 mm thick measuring about 10-25 cm were found, coiled to each other. On macroscopic examination, of both the worms it was found that both the worms had a short and rounded tail []. No lips were seen in the mouth. Under the microscope, the outer surface of the nematode's cuticle was found to have fine transverse striations and prominent longitudinal ridges []. Shorter worm had unequal caudal spicules hence identified as male dirofilarial worm. The longer worm had oesophagus anterior to the vulva and was identified female dirofilarial worms. On the basis of macroscopic and, microscopic examination, worm was thus identified as D. repens.\nThe hemogram showed hemoglobin 13 g%, total leucocyte count 10,200/mm3 and differential count showed eosinophilia, with absolute eosinophil count 2060/mm3. The peripheral smear showed relative eosinophilia without any parasite. No microfilaria were seen in peripheral blood. The patient did not review after the excision of the nodular swelling for follow-up.