ABSTRACT
BACKGROUND: A young boy presented with acute ethmoiditis and recurrent periorbital swelling. The periorbital swelling was confirmed to be caused by a rare condition. CASE PRESENTATION: Debut symptoms were acute rhinitis, unilateral periorbital swelling, fatigue, and swelling in the temple region, probably caused by an insect bite. Magnetic resonance imaging (MRI) of the sinuses showed bilateral ethmoiditis and unilateral periorbital cellulitis without subperiostal abscess formation, and antibiotics were prescribed. Because of recurrence of the periorbital swelling, an interdisciplinary team started an investigation for a differential diagnosis. The infestation of Hypoderma tarandi was confirmed by recent history of hiking in reindeer habitat, typical clinical presentation and detection of IgG hypodermin C antibodies. INTERPRETATION: Human myiasis by Hypoderma tarandi is a rare condition in Norway. Typical clinical signs are unaffected general condition, migration of swelling in the forehead, recurrent unilateral periorbital swelling and normal CRP levels. Early-stage diagnosis and treatment will contribute to rapid symptom relief and prevent rare eye and intracranial complications. This case illustrates the importance of investigation for other conditions when the disease course is unexpected. The authors emphasise that knowledge about this disease is important in a variety of medical specialties.
