Allopurinol induced granuloma annulare in a patient of lepromatous leprosy

Abstract

Granuloma annulare (GA) is a benign, inflammatory dermatosis involving dermis or subcutis with unknown etiology and poorly understood pathology. GA has characteristic histological features of necrobiosis, granuloma formation and abundant mucin deposition. Various predisposing factors, systemic diseases and drugs have been implicated in the etiology. We hereby describe a case of 70 year old male who was a known case of lepromatous leprosy, taking multidrug therapy for 6 months presented with multiple discrete, annular, firm, non tender, smooth surfaced skin colored papular lesions ranging in size from 0.5-1 cm over back for 1 month. There was past history of intake of allopurinol for hyperuricemia which was started 1 year back. There was history of similar lesions 6 months back which healed within 1 month of stopping allopurinol and he started taking the drug for the past 4 months on his own without any medical advice. Histopathological examination showed superficial and deep perivascular lymphocytic infiltrate with numerous histiocytes scattered in the intersititum of reticular dermis and abundant mucin in between the histiocytes. Allopurinol was implicated as an etiological agent and dramatic improvement was seen after stopping the drug for a period of 4 weeks. Naranjo's algorithm showed a probable association with a score of 6. Thus the final diagnosis of allopurinol induced generalised interstitial granuolma annulare was made. Patient was advised to continue antileprotic drugs, low purine diet and avoid allopurinol intake.

Granuloma Annulare: A Clinical Update

“…Infliximab, adalimumab, etanercept [27], dupilumab [28], allopurinol [29], topiramate [30], interferon-alfa [31], amlodipine [32], Other forms of treatment Phototherapy [33], gold therapy [34], injection of collagen [35], mesotherapy [36]…”

Necrobiosis lipoidica and granuloma annulare: Part 2- Granuloma annulare

“…4,5 Sun exposure and phototherapy with psoralen combined with ultraviolet A are also reported to precipitate GA. 4,6 Reported drug causes of GA included amlodipine, gold, allopurinol, diclofenac, quinidine, intra-nasal calcitonin and anti-tumour necrosis factor (TNF) agents. 6,7 In one study 15% of patients attributed onset of GA to psychological stress. 5 It has been suggested that GA is due to a delayed type hypersensitivity reaction, 5 but other theories have also been proposed.…”