Unsuspected lymphomatoid granulomatosis in a patient with antisynthetase syndrome.

Clinical diagnosis of lymphomatoid granulomatosis (LYG) often is difficult, especially in patients with multiple comorbidities. We present a 60-year-old woman with worsening fatigue, night sweats, unintentional weight loss, and dyspnea of 2 weeks' duration. Her medical history was remarkable for recent radiation therapy for recurrent breast cancer and antisynthetase syndrome complicated by interstitial lung disease and controlled with azathioprine. Computed tomography showed ground-glass opacities and nodular infiltrates in all lung lobes, raising concern for radiation pneumonitis and drug toxicity. Skin examination revealed erythematous and hemorrhagic papules, macules, and blisters on the lower leg. A diagnosis of LYG was made on a skin biopsy showing large angiocentric Epstein-Barr virus (EBV)-positive B cells. The patient soon progressed to develop nodal large B-cell lymphoma and died 6 weeks later. This rare report of LYG in a patient with antisynthetase syndrome highlights the diagnostic difficulty and aggressive course of LYG as well as the important role of skin biopsy in establishing the diagnosis.