Formation of double minutes by breakdown of a homogeneously staining region in a refractory anemia with excess blasts.

A patient suffering from refractory anemia with excess blasts in transformation had four different bone marrow karyotypes. These were 46,XY; 45,X,-Y; 45,X,-Y, 5q-,19q+; and 43,X,-Y,-9,-17,5q-,+dmin. The most plausible explanation for this is proposed to be formation of a homogeneously staining region on chromosome #19, followed by its breakdown into double minutes.

Serum crosslinked fibrin (XDP) and fibrinogen/fibrin degradation products (FDP) in disorders associated with activation of the coagulation or fibrinolytic systems.

Soluble crosslinked fibrin derivatives (XDP) in serum were determined by enzyme immunoassay utilizing monoclonal antibodies and compared with serum fibrinogen/fibrin degradation products (FDP) assayed by conventional techniques. In healthy subjects and patients with miscellaneous disorders not usually associated with activation of the haemostasis mechanism, mean XDP levels were 45 and 70 ng/ml respectively. However, elevated levels of XDP occurred in conditions commonly associated with intravascular and possibly extravascular activation of the coagulation system. Markedly raised mean XDP values (677-6900 ng/ml) occurred in treated pulmonary embolism, disseminated neoplasia, severe inflammatory disorders and complicated postoperative states, and lesser but significant elevation (mean 150-400 ng/ml) in treated venous thrombosis, uneventful postsurgical states, localized neoplasia, liver disease and symptomatic arterial disease. Levels during initial streptokinase therapy (mean 24 000 ng/ml) fell tenfold as treatment was continued. The degree of XDP elevation over normal values was significantly higher than that of FDP in conditions with a propensity for venous thrombosis (post-operative states, disseminated neoplasia and inflammatory diseases) than in liver disease, localized neoplasia or patients receiving heparin therapy for venous thromboembolism.

Register of chromosomal abnormalities in Queensland.

The development and use of the computer-aided retrieval of karyotypes (CAROK), a register of chromosomal abnormalities in Queensland, is described. The six independent cytogenetic laboratories serving the population of 2.2 million contribute data to the register which provides total population information on the occurrence of chromosomal abnormalities, without selection. CAROK policy on confidentiality, security, access, and safety of data is described in detail. A cytogenetic register such as this ensures a reliable permanent file of results, facilitates research, and provides a data base which will enable questions of clustering or secular trends to be answered efficiently. The register is complete for the years 1976-1981, and contains information on 880 consecutive abnormal cases; in this sense, the data constitute an unselected six-year series of diagnosed chromosomal abnormalities in Queensland. These figures show an average incidence figure (over a six-year period) for newly diagnosed cases of chromosomal abnormality of 6.61/100 000 general population per year.

Transfusion therapy of thrombocytopenia: a reappraisal.

In the management of thrombocytopenia, platelet concentrated (PC) were given only to patients who had neither frank haemorrhage nor significant anaemia. Fresh whole blood (FWB) was preferred for those with the former, and platelet-rich red cell concentrate (PRC) for those with the latter complication. As a result of this approach it was found that only 6% of 412 therapy courses required PC, 37% required FWB and the remaining 57% required PRC. These are the findings of a year's survey of the requirements of patients in a predominantly urban population of approximately 1,200,000. The surprisingly high proportion of patients with complications requiring transfusion therapy, and the 24-hour availability of FWB and PRC in a metropolitan blood bank, have made PC transfusion an elective procedure and eliminated the need for a PC bank. Moreover, a better approach to treatment is available whilst a significant saving of blood donations is effected.

A rapid method for assessing megathrombocytes: its application to thrombocytotic and acquired thrombocytopenic states.

A rapid technique suitable for routine laboratory use for determining the percentage of large platelets in the peripheral blood is described. In 50 haematologically normal subjects, megathrombocytes (platelets with a volume of 16-33 fl) constituted 3.0-16.6% (mean +/- 2 SD) of the platelet count. Of the 10 patients examined with immune thrombocytopenic purpura, an increased percentage of megathrombocytes (mean 26.6%) was found in all with severe thrombocytopenia, and in 6 of 8 (mean 19.8%) with moderate thrombocytopenia; the percentages were not influenced by prior splenectomy. Six of 12 patients with severe hypomegakaryocytic thrombocytopenia had an increased percentage of large platelets (mean 15.9%), as did one of 21 patients (mean 9.9%) with moderate thrombocytopenia of simimlar aetiology. When patients with nearly identical platelet counts were compared, the mean percentage of megathrombocytes was greater in immune than in hypomegakaryocytic thrombocytopenia for both severe (t=3.17, P less than 0.01) and moderate (t=4.5, P less than 0.001) thrombocytopenia. An increased percentage of large platelets (mean 21.9%) was found in 6 to 8 patients with disseminated intravascular coagulation, in 7 of 20 (mean 15.8%) with chronic myeloproliferative disorders and in one of 15 (mean 8.8%) with reactive thrombocytosis. Determination of the percentage of megathrombocytes by this technique assists in differentiating immune thrombocytopenia from hypomegakaryocytic thrombocytopenia, in diagnosing mild disseminated intravascular coagulation, and in determining whether thrombocytosis is reactive or a consequence of a myeloproliferative disorders.

Successful use of combination chemotherapy in pure red cell aplasia associated with malignant lymphoma, histiocytic type.

A case of pure red cell aplasia developing in a woman aged 78 is reported. Biopsy of an enlarged axillary lymph node disclosed a malignant lymphoma, histiocytic type. Therapy with intermittent cyclophosphamide and prednisone was instituted. There was rapid remission of the red cell aplasia. Clinical recurrence of the histiocytic lymphoma has not occurred.