RESUMEN
Linear IgA bullous dermatosis (LABD) is a rare, idiopathic, or drug-induced vesiculobullous disease caused by IgA autoantibodies in the basement membrane zone. An 84-year-old man was started on spironolactone two weeks before presentation for the management of hypertension and heart failure with preserved ejection fraction. He presented to our hospital for evaluation of worsening lower extremity swelling and a painful pruritic rash that started on the day preceding his presentation. On examination, he had 3+ lower extremity edema and an erythematous, painful, pruritic, bullous rash on all his extremities. He had a significantly elevated IgA level (1033 mg/dL). A lesional skin biopsy demonstrated epidermal ulceration with degenerated collagen fibers. Direct immunofluorescence of the perilesional skin showed linear IgA at the dermal-epidermal junction. The rash resolved following steroid therapy and discontinuation of spironolactone. There have been previous reports of bullous pemphigoid induced by spironolactone. To our knowledge, LABD associated with spironolactone has not previously been reported.
RESUMEN
ALK rearrangements occur in up to 10% of spitzoid melanocytic neoplasms. No reported cases have shown homozygous deletion of 9p21 (CDKN2A) or gains of 6p25 (RREB1) or 11q13 (CCND1), which have been associated with aggressive clinical behavior. Here we report 2 unique cases. Case 1 occurred in a 9-year-old male with a 14-mm nodule on the anterior left thigh. Biopsy revealed an ALK-positive Spitz tumor containing an irregular nodule of densely packed melanocytes with increased mitoses and loss of p16 immunoreactivity. FISH analysis showed homozygous deletion of 9p21 and gain of 6p25. Sentinel lymph node biopsy revealed small subcapsular foci of tumor. Case 2 occurred in a 7-year-old female with a 12-mm nodule on the anterior right ankle. Biopsy revealed an ALK-positive Spitz tumor containing an expansile nodule of pleomorphic epithelioid melanocytes with numerous mitoses and loss of p16 immunoreactivity. By FISH, the nodule showed homozygous deletion of 9p21 and gains of 6p25 and 11q13. Our cases show the transformation of tumors produced by an activating kinase fusion gene (ALK) through secondary genetic changes including loss of tumor suppressor activity (CDKN2A). Long-term follow up will be important to further define the behavior of these unique Spitz tumors.