Pyoderma gangrenosum and cobalamin deficiency in systemic lupus erythematosus: a rare but non fortuitous association

BACKGROUND: Pyoderma gangrenosum (PG) is an uncommon, idiopathic, ulcerative neutrophilic dermatosis. In many cases, PG is associated with a wide variety of different disorders but SLE in association with PG is relatively uncommon. In this article we present the case of a middle aged patient with PG as the initial clinical presentation of SLE. We also provide a brief review of cobalamin deficiency which occurred in our patient and evidence-based management options. CASE PRESENTATION: A 35 years old man presented with a 5 month history of debilitating painful lower limb and scrotal ulcers. This was associated with polyarthralgia and morning stiffness involving both hands. He also complained of swallowing difficulties. He had unintentional weight loss of 10 kg and fatigue. Physical examination revealed alopecia, multiple cervical lymphadenopathies, bilateral parotid gland enlargement and atrophic glossitis. There was Raynaud’s phenomenon noted over both hands and generalised hyper-pigmented fragile skin. Laboratory results disclosed anaemia, leukopenia, hyponatraemia and hypocortisolism. Detailed anaemic workup revealed low serum ferritin and cobalamin level. The autoimmune screen showed positive ANA, anti SmD1, anti SS-A/Ro 52, anti SSA/Ro 60, anti U1-snRNP with low complement levels. Upper gastrointestinal endoscopy with biopsies confirmed atrophic gastritis and duodenitis. Intrinsic factor antibodies and anti-tissue transglutaminase IgA were all negative. Punch biopsies of the leg ulcer showed neutrophilic dermatosis consistent with pyoderma gangrenosum. Based on the clinical findings and positive immunologic studies, he was diagnosed as systemic lupus erythematosus. His general condition improved substantially with commencement of corticosteroids, immunosuppressants and vitamin supplements. CONCLUSIONS: We report a case of PG as the first manifestation of SLE which was treated successfully with immunosuppressants and vitamin supplements. Our report highlighted the need to consider connective tissue diseases such as SLE in a patient presenting with PG in order for appropriate treatment to be instituted thereby achieving a good outcome.