Unique eosinophil granules in a case of T-cell lymphoma.

A 41-year-old man developed intense itching without visible cutaneous changes, epigastric pressure pain, and a slight intolerance to alcohol. He was found to have persistent blood eosinophilia. The eosinophil granulocytes were of abnormal appearance in the light microscope: larger than normal, the nuclei were multilobulated (4-6 lobes), the cytoplasm contained atypical, large granules, ample glycogen, and up to 12 vacuoles. In the electron microscope too the eosinophil granules were entirely atypical, having an electron-dense matrix, often with a light central inclusion body which was inhomogeneous, having longitudinally oriented structures with a periodicity of about 10 nm. These findings are quite contrary to normal eosinophil granules. Enzymic studies of cytoplasmic enzymes from the granulocytes revealed a greatly reduced content of eosinophil cationic proteins, whereas 5 (7) other enzymes were present in a normal or slightly reduced quantity. The phagocytic capacity of the eosinophils against latex particles was normal. The patient developed generalized lymphomas, histologically very malignant, of the convoluted, acid phosphatase positive cell type (T-cell lymphoma). Sub-population studies of lymphocytes from a lymph node revealed 58% TE cells, while the remainder were B cells. At death, 3-1/2 years after the onset of symptoms, severe endomyocardial fibrosis was found. The thymus could not be identified. It is concluded that lymphomas should be described on the bais of clinical, histological, and histochemical criteria as well as studies of lymphocyte sub-populations and that the highly unusual eosinophil granulocytes still deserve particular attention. The endocardial fibrosis is assumed to have been due to substances liberated from the eosinophil cells.