耳下腺を含む頸部に多発したトキソプラズマ性リンパ節炎例

抄録

Infections by the coccidian parasite Toxoplasma gondii usually do not cause obvious symptoms in adults. Lymphadenopathy is the most common clinical manifestation of acute acquired toxoplasma infection in healthy individuals, but rarely presents as a parotid mass. Herein, we report a case of multiple masses in the parotid region caused by toxoplasmosis. A 35-year-old woman had visited another hospital with a one-month history of preauricular swelling. Computed tomography and magnetic resonance imaging revealed multiple masses in the left parotid region and bilateral cervical regions. Fine-needle aspiration cytology from the parotid mass did not reveal any evidence of malignancy. Histopathological examination of an excised lymph node from the right submandibular region revealed follicular hyperplasia, monocytoid B-cell proliferation, and granuloma formation. Serological tests revealed high serum levels of both IgM and IgG antibodies against Toxoplasma gondii. Based on the findings, we made the diagnosis of toxoplasmic lymphadenitis. The lymphadenopathy gradually subsided through six months of follow-up.

Toxoplasmic lymphadenitis has few characteristic findings, but toxoplasma infections should be included in the differential diagnosis of massive swellings in the salivary gland area.