LAUSR

Acne agminata (AA) is a rare centrofacial papular eruption of unknown aetiology. There are very few reports of effective treatment options for AA. We report a case with minimal response to conventional treatments, including oral corticosteroids, lymecycline and two courses of isotretinoin. Topical dapsone gel (5%) was chosen based on reports of the efficacy of oral dapsone in AA, but with topical dapsone having a lower potential for adverse effects (AEs). The treatment was well-tolerated and considerable benefit was seen. This is the first report of efficacy with this novel topical agent for AA. A 31-year-old white man presented with asymptomatic facial papules. His medical history was not significant, and he was not taking any regular medication. Physical examination revealed symmetrical facial papules involving the chin, cheeks, nose and periorbital skin (Fig. 1a). The clustered monomorphous papules were erythematous with a yellowish hue (Fig. 1b). There were no comedones. Histological examination of a punch biopsy of a papule demonstrated folliculocentric, noncaseating granulomata in the dermis surrounded by a dense infiltrate comprising lymphocytes and plasma cells with Langhans giant cells (Fig. 1c). Periodic acid– Schiff, Ziehl–Neelsen and gram stains excluded infective causes, and enzyme-linked immunospot testing for tuberculosis was nonreactive. Chest radiography, full blood count, renal and liver profile, and levels of Creactive protein, serum angiotensin-converting enzyme and calcium were normal. These clinicopathological features were consistent with AA. Initial treatment with prednisolone (10 mg daily for 1 month) followed by lymecycline (408 mg daily for 3 months) were ineffective. Two sequential 6-month courses of isotretinoin 40 mg did not clear the rash, but led to a slight reduction in the size and prominence of the papules; however, ongoing disease activity remained, with new lesions continuing to develop. Therefore, 24 months after the initial presentation, topical 5% dapsone gel was commenced, initially twice daily, following a normal glucose-6-phosphate dehydrogenase (G6PD) reading. We decided on therapy with topical dapsone gel, based on reports of successful treatment of AA with oral dapsone. Upon review at 3 months (Fig. 2), the existing lesions were smaller and less inflammatory, and there were no new papules. Over the next 6 months, the dapsone gel was stopped intermittently, but this led to rapid recurrence, indicating ongoing disease activity which the topical dapsone was controlling. The patient denied any AEs and found the formulation very tolerable. Full blood count repeated after 4 months of treatment was normal. After 11 months, the treatment was successfully stopped with no recurrence. AA, also called lupus miliaris disseminatus faciei (LMDF) or facial idiopathic granulomas with regressive involution (F.I.GU.R.E.), is a rare granulomatous condition that usually affects young adults, predominantly localizing to the central face with characteristic periorbital involvement. Histology typically shows tuberculid granulomas in the dermis with central caseating necrosis, with variants reported, including sarcoidal-like granulomas, as in our case. The aetiology is uncertain, but it may represent a form of granulomatous rosacea or a granulomatous reaction to ruptured hair follicles. It can resolve spontaneously, albeit with depressed, disfiguring scars. Due to the rarity of AA, the evidence for treatment options is sparse. Prednisolone used in the early phase may reduce scar formation, while isotretinoin (40 mg daily for 3–40 months) is reported to hasten resolution and the evidence for doxycycline (100 mg once or twice daily) is encouraging, but none of these options are uniformly effective. Clofazimine, an antituberculous PD