Pediatric IgG4-related dacryoadenitis and sialadenitis (Mikulicz's disease) with acquired hemophilia A: A case report and review of literature.

We report a case of IgG4-related dacryoadenitis and sialadenitis (Mikulicz's disease) with acquired hemophilia A (AHA) in a pediatric patient. An 11-year-old female presented with intermittent swelling of the bilateral upper eyelids and neck areas. Clinical examination revealed bilateral swollen upper eyelids with palpable mass lesions in the lacrimal fossa. The submandibular and sublingual glands were enlarged, tender, and movable. Neck ultrasound showed bilateral gland enlargement with irregular hypoechoic parenchyma. Maxillofacial magnetic resonance imaging (MRI) revealed bilateral lacrimal glands enlargement, homogeneous enlarged bilateral submandibular and parotid glands, measuring 4.7 × 3.9 cm. Laboratory investigation showed increased activated partial prothromboplastin time (80.9 s), markedly decreased FVIII activity (0.6%), a high titer of FVIII inhibitor (480 Bethesda units/mL), and a remarkable increase in serum IgG4 level (1005.68 mg/dL). A left submandibular gland biopsy revealed marked lympho-plasmacytic infiltration with scattered eosinophils. Immunohistochemical staining for IgG4 showed numerous IgG4-positive plasma cells (>100 per high-power field), with a ratio of IgG4-positive to IgG-positive cells >40%. The symptoms were markedly relieved following corticosteroid therapy. IgG4-related dacryoadenitis and sialadenitis (Mikulicz's disease) with acquired hemophilia A (AHA) can also be seen in the pediatric population and should be considered a differential diagnosis in patients with relevant symptoms.