Human parvovirus B19 in bone marrows from adults with acquired immunodeficiency syndrome: a comparative study using in situ hybridization and immunohistochemistry.

Human parvovirus B19, which infects and lyses erythroid precursors, can cause severe anemia in patients with immunodeficiency. The incidence of parvovirus infection in adult acquired immunodeficiency syndrome (AIDS) patients is unknown. Eighty-one archival formalin-fixed, paraffin-embedded (FFPE) bone marrow biopsies from 73 AIDS adults were immunostained with monoclonal R92F6 against B19 VP1 and VP2 capsid proteins using streptavidin peroxidase and streptavidin alkaline phosphatase techniques. In addition, the same tissues were hybridized in situ with a digoxigenin-labeled parvovirus B19 DNA probe. Five FFPE bone marrows, from 3 HIV-negative patients with positive immunoglobulin M (IgM) serology for parvovirus B19, and 1 parvovirus B19-infected fetal liver were positive controls. By immunoperoxidase, all tissues were negative with R92F6 except the fetal liver, which exhibited strong positivity predominantly in viral inclusions. With immunoalkaline phosphatase, all positive controls were immunoreactive with R92F6; however, the AIDS marrows were negative. With in situ hybridization (ISH), all positive controls and 7 of 81 (8.6%) of AIDS marrows were positive for B19 parvovirus DNA. We conclude that ISH is more sensitive than R92F6 immunohistochemistry in parvovirus B19 detection. A small but significant number of bone marrows from AIDS adults shows evidence of human parvovirus B19 infection.

The nuances of lymphocytopenia.

We have discussed the causes of lymphocytopenia and attempted to categorize them according to pathogenesis. This effort may be tenuous at best, because so much is still unknown about lymphocyte function and kinetics. In describing pathogenesis we have reported what has been published and not speculated on mechanisms when they were not stated. Many of these reports were decades apart, and the technical resources available to the investigators were varied. We suspect, for example, that many of the lymphocyte changes secondary to inflammation and infection will have a common pathogenesis (for example, cytokines and endotoxins). Undoubtedly, the picture will become much clearer in the years ahead.

The platelet volume-number relationship in patients infected with the human immunodeficiency virus.

The pathophysiology of thrombocytopenia in the acquired immune deficiency syndrome has not been elucidated completely. Many findings in these patients are identical to those with immune thrombocytopenic purpura. However, recent findings in acquired immune deficiency syndrome patients including the effect of zidovudine on platelet count and the demonstration of ultrastructural changes and viral RNA in megakaryocytes, have suggested that the human immunodeficiency virus may directly infect megakaryocytes, and play a role in acquired immune deficiency syndrome-related thrombocytopenia. To investigate further the mechanism of decreased platelet counts in human immunodeficiency virus-infected patients, the platelet volume-number relationship and corresponding bone marrow findings in 34 patients infected with human immunodeficiency virus were studied. Parameters evaluated included platelet count and mean platelet volume; bone marrow cellularity, megakaryocyte number, and number and percentage of denuded megakaryocyte nuclei. Two thirds of the platelet counts were low, and of these 92% had an inappropriately low mean platelet volume. These individuals had a platelet-volume number relationship that is very similar to that seen in myelosuppressive disorders. In addition, more than 90% of the bone marrows from thrombocytopenic patients had either normal or decreased numbers of megakaryocytes. These observations provide additional evidence to support the hypothesis that the pathophysiology of human immunodeficiency virus-associated thrombocytopenia may be due, at least in part, to a direct effect on the megakaryocytes.

Hematology analyzers.

An overview of current hospital hematology analyzers has been presented. The technology involved is extraordinarily sophisticated and has provided us with interesting new and potentially useful parameters. Even the instrument evaluation process is becoming increasingly complex, but new standards are being developed that provide guidance for users. As the forces of technology and cost-containment converge, pressures arise to alter our thinking about traditional laboratory testing. Recent interest has been particularly focused on the differential count. The hematology laboratory is vastly changed from that of 25 years ago, and it's almost impossible to speculate on what it will be like a quarter century from now.

ABH and Lewis blood group expression in colorectal carcinoma.

The expression of ABO(H) and Lewis blood group antigens on 68 colorectal carcinomas from 63 patients was studied by immunohistochemical staining of tissue specimens. The pattern of antigen expression was as follows: ABH was expressed in normal tissue only in secretors and was expressed in the proximal but not distal colon. In tumors, there was net loss of ABH expression in the proximal and net gain in the distal colon. Some nonsecretor tumor tissue expressed ABH. Lewis expression was similar to but less strong than ABH. Its expression occurred only in secretors and in normal epithelium only in the proximal colon. In tumors there was net loss of antigen expression proximally and net gain in the distal colon. There was no expression of Lewisb in tumors of nonsecretors. Lewisa antigen was expressed throughout the normal colon in secretors and nonsecretors with no discernible difference between proximal and distal colon. In tumors, net loss of expression of Lewisa occurred throughout the colon. No inappropriate blood group expression was observed in this study. With few exceptions, H expression paralleled expression of A and B in non-0 patients. Metastatic tumor antigen expression was similar to that of the primary in most cases. Alterations in antigen expression were not clinically or histologically distinctive.

Double heterozygosity for hemoglobins C and Lepore in an American black man.

We describe a patient doubly heterozygous for hemoglobin (Hb) C-Hb Lepore. To our knowledge, this is only the second case reported in the United States. The erythrocyte morphology and clinical findings were suggestive of Hb C-beta-thalassemia. Following Hb electrophoresis, the correct diagnosis was postulated and was subsequently confirmed by a reference laboratory. We also present the family pedigree of Hb abnormalities. The morphologic alterations of the erythrocytes presented in this article, when seen in conjunction with the distinctive electrophoretic pattern, should suggest the abnormality in undiagnosed cases.

The distribution of blood group substance H and CEA in colorectal carcinoma.

The distributional patterns of blood group substance H and carcinoembryonic antigen (CEA) in 20 colorectal carcinomas from 17 patients, were investigated. Prognosis in these cases was more obviously related to histologic classification and pathologic stage than to BGS and CEA distributional patterns or preoperative plasma CEA levels. The distribution of H and CEA was similar to that found by other investigators for A and B blood group substances with the exception that areas of identical localization could be shown in at least some areas of each tumor studied that was positive for both antigens. The relationship of CEA and BGS is as yet unknown, but it seems probable that they can occur simultaneously in the same tissue.

Carcinoma-related alterations of glycosyltransferases in human tissues.

The glycosyltransferases responsible for catalyzing additions of A, B, and H sugars to cellular acceptors were studied in 23 cases of primary carcinoma. The carcinomas were derived from mouth, tongue, larynx, lung, cervix, esophagus, stomach, and colon. Comparisons of A, B, and H enzymes were made between mucosal extracts from tumor and from normal adjacent tissue and, in the case of gastrointestinal tract, extracts derived from mucosae of individuals free of disease. The most prevalent finding was that of alpha-2-fucosyltransferase (H enzyme) deficiency in tumor extracts from Group A, B, and O patients in relation to the normal tissue counterpart (20 cases). Exceptions were observed in one case of carcinoma of the stomach and in two of seven cases of carcinoma of rectum or sigmoid. In four of nine Group A patients (carcinoma of the mouth, tongue, ascending and transverse colon), N-acetylgalactosaminyltransferases (A enzymes) were demonstrated but were deficient in relation to the normal adjacent counterpart. A enzymes were not demonstrable in normal and tumor extracts from distal colon in five cases. Differences between tumor extracts and normal adjacent tissue were noted in D-galactosyltransferase (B enzyme) derived from carcinomas of larynx and esophagus, but B enzyme was not demonstrated in tumor or normal tissue derived from the sigmoid colon. Study of the normal distribution of H enzyme in gastrointestinal mucosa indicated the presence of relatively high enzyme levels in stomach and upper intestine but low levels in distal colon.

Ultrastructural diagnosis of histologically atypical idiopathic thrombocytopenic purpura.

The histological and electron microscopic findings in the spleen of a 61-year-old white man with corticosteroid-unresponsive idiopathic thrombocytopenic purpura (ITP) are described. Light microscopically, the spleen lacked features characteristic of ITP, such as germinal centers and foamy histiocytes. Ultrastructurally, however, platelet phagocytosis, which is diagnostic of this entity, was readily demonstrable in splenic cord macrophages.

Evaluation of an automated blood smear analyzer.

The performance of a diff3 System prototype instrument that does automated leukocyte differential counts, erythrocytic morphology determinations, and leukocyte count and platelet count estimates, was compared with performance by laboratory personnel for a five-week period in an active general hospital. Using experienced supervisors as the referee method, this instrument performed as well as the routine laboratory staff in all aspects of leukocyte differential counting. With respect to erythrocytic morphology, estimates of hypochromia were inferior to those of the routine laboratory staff; comparisons of estimates of macrocytosis and polychromasia were not significantly different. Leukocyte and platelet numerical estimate performance by the diff3 System was not as good as that of automated cell-counting instruments, but categorization of platelet concentration as normal or abnormal did compare favorably with estimation by laboratory personnel. The flagging of abnormal slides by the instrument was comparable in sensitivity to that by the routine laboratory staff; however, specificity was less, with a significantly greater number of false positives obtained by use of the instrument.