[The consequences of subcutaneous India ink injection to produce factitial disease. Bilateral mastectomy, lymph node dissection, irradiation, and continued suspicion of neoplasia].

A 68-year-old woman with insulin-dependent diabetes mellitus presented with blue nodules on the ventral aspect of the thorax. According to the past history, these lesions had developed repeatedly. She had already had bilateral mastectomies and lymph node dissection. The histologic diagnosis was always mastitis with plasma cells and no neoplasia. Yet another biopsy was taken; the subcutis was stained blue-black. Histology revealed exogenous black pigment and mastitis. With Raman spectroscopy the pigment was identified as carbon black, which is a component of India ink. These findings together with the unusual course of the disease suggested the diagnosis of an artificial disorder. The likely conclusion is that our patient, over years, used her own (insulin) syringe to inject India ink into her skin and subcutaneous tissue; the damaging effect and tissue reaction was probably caused by preservatives such as phenol.