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A 52-year-old male presented with an anterior mediastinal tumor associated with a 2-year history of myasthenia gravis. The patient underwent thymectomy and a 185-g, 10 X 8 X 3.5 cm, well-delineated tumor was resected. On histologic examination the tumor proved to be a thymolipoma composed of mature adipose elements containing cords and nests of thymic tissue. The latter consisted mainly of cortical areas, the thymocytes of which displayed an immunohistochemical profile of cortical cells, i.e., CD 1+, CD 4+, CD 8+, and frequently Ki 67+. Ultrastructural study confirmed the predominant cortical differentiation of the thymic component. No germinal centers, dendritic reticulum cells, or myoid cells were detected by histologic, immunohistochemical, and ultrastructural studies. The association of thymolipoma with myasthenia gravis is rare; this case is the 10th reported. Our findings lead us to believe that (a) the cortical differentiation of the thymic component and the active thymocyte proliferation could represent a factor leading to myasthenia gravis; and (b) thymolipoma could be a peculiar form of thymoma rather than a mixed tumor of mesenchymal and entodermal origin, a lipoma, or a hamartoma of the thymic gland. The reported association of thymolipomas with other immune disturbances or with neoplastic conditions usually associated with true thymomas support these findings.

Three patients of a French family demonstrated an association of multiple endocrine neoplasia type 2A (MEN 2A) with a pruritic scapular skin lesion. The lesions are similar to those described as familial cutaneous lichen amyloidosis in unrelated MEN 2A and medullary thyroid carcinoma families, but histological, immunohistochemical, and ultrastructural analysis of skin biopsies from each patient in the French family did not show amyloid deposition. The topography of the lesion follows dermatomes C8-D3. The patients report not only pruritus but also paresthesia and hyperalgesia, and one showed touch hypoesthesia and pain hyperesthesia in the area of the lesion. Such an association of cutaneous and neurological features suggests notalgia paresthetica (NP), a neuropathy of the posterior dorsal rami nerves. We thus suggest that the cutaneous lesions associated with MEN 2A might be secondary to pathology in the neural crest-derived dorsal sensory nerves. The amyloid, when present, would be secondary to scratching. We propose that patients presenting with familial NP be suspect for MEN 2A.

Fluindione (Previscan) is an oral anti-vitamin K anticoagulant, widely prescribed in France. Contrary to phenindione, which is also an indanedione derivative, very few cases of immunoallergic reactions have been described.A 68 year-old man, treated with fluindione for cardiac arrhythmia, presented with a pustular eruption and erythema twenty days after initiation of treatment. The eruption was associated with hyperthermia, arthralgia, neutrophilia (11,000/mm2), hepatic cytolysis and renal involvement including acute renal failure, hematuria and proteinuria. In view of the absence of any earlier case in the literature, we did not impute fluindione and the drug was reintroduced and led to the rapid recurrence of all the same manifestations.These manifestations were consistent with an immunoallergic reaction to fluindione (probable intrinsic imputability I3) and acute interstitial nephritis (probable intrinsic imputability I3). We believe this is the first case of acute generalized exanthematous pustulosis induced by fluindione (intrinsic imputability Bo). A few rare cases of fluindione-induced hypersensitivity reactions and acute interstitial nephritis, however, have been described.