Hemophagocytic syndrome associated with inappropiate secretion of antidiuretic hormone in lymphoma and acute myeloblastic leukemia: report of two cases.

Hemophagocytic syndrome (HPS) is a rare clinicopathological disorder characterized by systemic proliferation of phagocytizing histiocytes associated with fever, cytopenias, lymphadenopathy, hepatosplenomegaly, and disseminated intravascular coagulopathy. We present the association of hemophagocytic syndrome associated with inappropriate secretion of antidiuretic hormone (SIADH) in two cases of hematological malignancies; anaplastic large cell lymphoma (ALCL) and acute myeloblastic leukemia (AML M4) In the patient with lymphoma, the diagnosis of lymphoma, HPS and SIADH were concurrent. In the patient with AML, HPS and SIADH were observed while the patient was in hematological remission. Thus it seems that patients with HPS may also carry a risk for the development of SIADH; the relationship with HPS and SIADH should be further investigated.

Increased levels of tissue factor pathway inhibitor may reflect disease activity and play a role in thrombotic tendency in Behçet's disease.

Tissue factor pathway inhibitor (TFPI) is a Kunitz-type proteinase inhibitor that has a crucial role in haemostasis and is primarily synthesized in the vascular endothelium. We investigated plasma total TFPI, antiphospholipid antibodies, and some other coagulation and fibrinolytic system parameters in 30 patients with Behçet's disease and 15 controls by the enzyme-linked immunosorbent assay method. TFPI levels were significantly higher in the Behçet's group (119 +/- 57.5 ng/ml) compared with the control group (74.8 +/- 31.5) (P < 0.009). We also noted a statistical significance in TFPI levels between patients with active disease (n:16) (139 +/- 55) and patients without activation (n:14) (96 +/- 53) (P < 0.03), whereas inactive patients lacked any significance when compared with the control group (P < 0.29). Other parameters disclosed no statistical significance between patients and control group except for elevated fibrinogen and plasminogen activator inhibitor-1 levels in the patient group (P < 0.003). Increased levels of TFPI may reflect a defensive mechanism like in other diseases characterized by thrombotic tendency and represent a parameter of disease activity.

Effect of Sialic Acid on Platelet Cryopreservation.

Sialic acid is a molecule which is responsible for the net negative surface charge of platelets. We investigated the effect of sialic acid on fresh and cryopreserved platelets. Platelet samples were obtained by platelet apheresis from 8 healthy donors. Platelet suspensions with different sialic acid concentrations (0, 1, 2 and 4 mg/mL) were studied for ADP and ristocetin induced platelet aggregation, basal and ADP induced P-selectin and glycoprotein- Ib/IX expression. Then platelet samples were cryopreserved in 5% DMSO with or without 4 mg/mL sialic acid. After thawing, P-selectin expression was compared with the control group. Six samples were also washed after thawing and P-selectin expression was again compared to unwashed samples. Sialic acid suppressed ADP induced platelet aggregation and P-selectin expression in a dose dependent manner. In cryopreserved samples, P-selectin expression of 4 mg/mL sialic acid containing group was found significantly higher than the control group (p< 0.001). In cryopreserved control group, P-selectin expression of thawedwashed group was significantly higher than thawed-unwashed group (p< 0.05). Our results indicate that sialic acid is not a good cryoprotective agent. Washing procedure after thawing to eliminate DMSO causes significant platelet activation.

Plasma Cell Leukemia: A Report of 5 Cases and Review of the Literature.

Plasma cells are occasionally observed in the peripheral blood of the patients with multiple myeloma. When the number of these circulating cells is significant, the term of plasma cell leukemia is used. We report 5 cases of plasma cell leukemia with poor prognosis with review of the literature.

The Role of Interleukin-1 Inhibitors on Acute Myeloblastic Leukemia Blast Proliferation; Future Potential for Biotherapy.

UNLABELLED: The effect of interleukin-1 (IL-1) as an autocrine growth factor on the proliferation of the acute myeloblastic leukemia (AML) blasts was studied. Bone marrow specimens were obtained from nine patients with different subgroups of AML. IL-1 receptor antagonist (IL-1RA) and IL-1 ß neutralizing antibody (IL-1ß NA) alone or in combination were added to the culture mediums of the AML blast cultures for the detection of their inhibitory effect on AML blast cell proliferation and colony formation. Average colony numbers in the IL-RA, IL-ßNA, and IL-IRA plus IL-IßNA included culture flasks, were 63.7 ± 21.5 %, 69.5 ± 19 %, 53.4 ± 23.7 %, respectively, as compared to those of the control (p < 0.01). Inhibition of colony formation by IL-IRA plus IL-IßNA was more prominent than by IL-IßNA alone (p < 0.01). No correlation between the inhibition of AML blast colony ormation and FAB AML subgroups was seen. RESULT: Both IL-1RA or IL-IßNA or in combination induced varying degrees of inhibition on blast colony formation. IL-I inhibitory molecules could be considered as an alternative therapy for AML in patients whose blast cells are sensitive to IL-1 inhibition.