Angiotropic large cell lymphoma (intravascular lymphomatosis) occurring after follicular small cleaved cell lymphoma.

Angiotropic large cell lymphoma is a rare, aggressive type of malignant lymphoma that primarily involves intravascular spaces and most often has clinical manifestations in the skin and central nervous system. Virtually any organ can be affected, however, including the lymph nodes and spleen. Peripheral blood involvement is usually not detectable morphologically. Conventional lymphoma in association with this entity has also been described. Herein we present a case of angiotropic lymphoma of B-cell lineage that affected the liver and skin. Reanalysis of a lymph node specimen that had been excised 3 years previously demonstrated a follicular small cleaved cell lymphoma. To our knowledge, this is the first reported case of possible evolution of follicular lymphoma to large cell lymphoma of angiotropic type.

Differential diagnosis of adult hemoglobin A, F, and S conditions. A case of G gamma-beta(+)-hereditary persistence of fetal hemoglobin.

Hemoglobin (Hb) S/beta(+)-thalassemia is a hemoglobinopathy of variable but potentially severe clinical course. The condition is usually confirmed by the presence of a microcytic anemia and elevated levels of Hbs S, F, and A2 by electrophoresis. However, other less common disorders of Hb structure and synthesis may exhibit laboratory findings that mimic Hb S/beta(+)-thalassemia but have a more favorable prognosis. We present a case occurring in a man with clinical and laboratory features that were suggestive of Hb S/beta(+)-thalassemia but with normocythemia. Although nonmicrocytic variants of beta(+)-thalassemia, including concomitant nutritional deficiencies, were considered, high-pressure liquid chromatography revealed nearly all of the patient's fetal Hb to contain only G gamma chains. This pattern is most consistent with the rate but clinically benign condition of Hb S/G gamma-beta(+)-hereditary persistence of fetal Hb, a nondeletional type of hereditary persistence of fetal Hb. We discuss a diagnostic approach to adult Hb A, F, and S conditions, including thalassemias and thalassemia-like syndromes.

A model for inferring the voluntary and involuntary causes of residential segregation.

It is clear that both voluntary and involuntary forces normally contribute to the residential segregation existing between groups. For the most part, the contribution of each dimension has not been determined. Rather, researchers operate as if either one or the other force is operating. In the United States, for example, black-white segregation is assumed to be imposed by whites on blacks, as if the latter were themselves totally indifferent to the racial composition in their areas of residence. On the other hand, it is assumed that segregation between white ethnic groups is at present purely a voluntary matter. In an earlier period, it was assumed that their segregation was both voluntary (reflecting desires to be among copatriots) and involuntary (reflecting the imposition of restrictions on residential movement by other groups as well as economic forces). But it has not been possible for investigators to determine the relative importance of each factor. Using asymmetrical segregation indexes, a rudimentary procedure is proposed for determining the relative importance of voluntary and involuntary forces operating to generate a given level of segregation. Data based on Black, Anglo, and Spanish residential patterns are then considered in terms of the proposed model.