Isolated noncaseating granulomatous inflammation of the lacrimal sac masquerading as a malignancy.

Idiopathic orbital granulomatous inflammation has been reported before, but isolated involvement of the lacrimal sac is extremely rare. The authors report the case of granulomatous inflammation in a 47-year-old-female limited to the lacrimal sac, nasolacrimal duct (NLD), and adjacent inferior meatal mucosa without any identifiable cause. She presented with rapidly progressive swelling involving the left medial canthal region and a palpable, nontender, nonregurgitant firm mass lesion extending above the medial canthus. The lacrimal irrigation was patent, and imaging showed a heterogeneous mass lesion involving the lacrimal fossa and extending into the NLD. The clinical presentation was suggestive of malignancy arising from the lacrimal sac, but histopathological findings of noncaseating granulomas, multinucleated giant cells, and scattered lymphoplasmacytic infiltrate involving the lacrimal sac and inferior meatal mucosa were suggestive of granulomatous inflammation. Her immunological workup was negative. She responded to oral steroids with complete clinical resolution maintained till 9 months of follow-up.