Case Presentation: A 60-year-old African American male with a recent diagnosis of thromboangiitis obliterans (Buerger’s disease) presented with new painful penile and scrotal ulcerations in the setting of digital ischemia, palmar skin lesions, bloody diarrhea, a 50-pound weight loss, and progressive dyspnea over the past six months. No vascular etiology for ischemia was found. Labs from one month ago showed a positive melanoma-differentiated antibody (MDA-5). Outside workup for malignancy was negative. Pertinent physical exam findings were a left-sided buccal ulcer, dusky right hand digits with gangrenous ulceration of the right fourth finger, palmar lesions, and an edematous penis with necrotic lesions. Key laboratory values included normal white blood cell and platelet counts, downtrending hemoglobin, elevated ESR and CRP, normal complements, normal aldolase, with negative dsDNA, rheumatoid factor and extractable nuclear antigens, ANCAs, APS studies, and RNA polymerase III. Repeat myositis panel showed elevated MDA-5, weakly positive EJ, and positive Anti-SS-A 52 kD Ab, consistent with MDA-5 dermatomyositis (DM). A left palmar punch biopsy revealed capillary dilatation and an intra-arteriolar, non-occlusive fibrin thrombus with vascular changes suggestive of thrombosis versus vasculitis. High-resolution CT chest suggested nonspecific interstitial pneumonia (NSIP); PFTs demonstrated a restrictive pattern. Multimodal treatment included antiplatelet and anticoagulation agents with high dose immunosuppression (prednisone, rituximab, mycophenolate mofetil, and cyclophosphamide), but ultimately failed to stop progression.

Discussion: MDA-5 DM generally presents as an amyopathic disease with an increased risk of rapidly progressive, and often fatal, interstitial lung disease (ILD), setting it apart from typical DM. The associated severe vasculopathy manifests as cutaneous ulcerations with necrosis, painful palmar papules, patchy alopecia, and oral lesions with typical cutaneous features of DM (heliotrope, malar rash, Gottron papules/sign). Few clinical features distinguish Buerger’s from other causes of digital ischemia, yet it rarely manifests systemically and affects a typical patient demographic of male smokers aged 25-35. Additionally, there are not many labs, biopsy characteristics, or CT angiographic findings that are specific for Buerger’s. This patient, who was over age 60, suffered from multiorgan disease affecting his skin, gastrointestinal tract, and lungs, but was given a presumptive diagnosis of Buerger’s. These affected systems and MDA-5 Ab positivity justified an expedited workup to initiate therapy for this quickly progressive disorder.

Conclusions: The differential for nonatherosclerotic vasculopathy leading to ischemia, necrosis, and possible autoamputation includes coagulative disorders, inflammatory diseases, and embolic phenomena but findings of palmar papules and ischemic cutaneous ulcerations warrant consideration of systemic autoimmune disease. Admission is necessary for immediate subspecialist involvement so that treatment and work-up can occur simultaneously. In this gentleman, presumption of Buerger’s disease, which has no immediate need for intervention, delayed treatment for this aggressive dermatomyositis. Early recognition of the mucocutaneous phenotype classic to MDA-5 DM can improve morbidity and survival. We strongly recommend excluding ILD even while awaiting serologic markers, which often take days to result.

IMAGE 1: Figure 1. Digital ischemia with autoamputation of right fourth finger.

IMAGE 2: Figure 2. Necrotic lesion on penile shaft and scattered ulcerations on the scrotum.