Shiril M. Hombal

Human infection with Pasteurella multocida is the leading cause of animal bite wound infection. Life-threatening infection may occur in patients with a variety of underlying disorders and an immunocompromised state. Infective endocarditis with P. multocida is very rare and only a few clinically diagnosed cases have been reported. Described here is an autopsy case of a 61-year-old man with polycystic kidney disease who had P. multocida bacteremia and acute infective endocarditis with multiple bacterial clumps involving bicuspid aortic valve. The organisms were gram negative. Apparently the sepsis with P. multocida was acquired via licking of leg ulcers by his pet dog, establishing an animal-related causal relationship. Because P. multocida is a very common flora of many animals, infection with this organism probably occurs more frequently than is commonly appreciated. High index of suspicion and early diagnosis, especially in immunocompromised patients, are warranted because the disease is potentially life threatening, yet is a readily treatable infection.

Two cases of lymphoma of large granular lymphocytes are reported. The first case expressed natural killer (NK) cell, some T-cell (CD 2, CD 5, CD 8), and HLA-DR antigens, but was negative for other T-cell (CD 3, CD 4, CD 7), T-cell receptor (TCR), B-cell, and myeloid antigens. Germline configuration was demonstrated for TCR, and immunoglobulin heavy and light chain genes. The second case expressed NK cell, some T-cell (CD 3, CD 7, CD 8), and TCR antigens, but was negative for other T-cell (CD 4, CD 5), B-cell, myeloid, and HLA-DR antigens. Rearrangement of TCR alpha and beta chains were detected. Thus, the findings of case 1 were consistent with true NK cell lineage and case 2 with NK-like T-cell lineage. Our report underscores the heterogeneity of this newly recognized lymphoma, which nevertheless carries a consistently poor prognosis and is probably more prevalent in the Asian population. This study also provides information concerning immunophenotypes of cellular infiltrates in internal organs and cytogenetic abnormalities in this lymphoma; neither has been reported frequently in the literature. The importance of detecting cytoplasmic granules in tissue imprints or electron micrographs for differentiating other T-cell lymphomas is emphasized, and the classification of large granular lymphoproliferative disorders is discussed.