As compared to kaolin clotting time, silica clotting time is a specific and sensitive automated method for detecting lupus anticoagulant.

Lupus anticoagulants (LAs) are antiphospholipid antibodies capable of interfering with the coagulation system and modifying in vitro the phospholipid-dependent clotting tests. Colloidal silica was used as activator to perform an activated partial thromboplastin time (aPTT) in 73 plasma samples with pathologically elevated kaolin clotting time (KCT) values using a photooptical automated coagulometer. Samples were incubated for 5 min with micronized silica, and after recalcification, the clotting times were measured. Pathologically prolonged results were confirmed by a confirmation and a neutralization test adding platelet-poor normal plasma (PPNP) and natural phospholipids, respectively. Silica clotting time (SCT) was abnormally elevated in 72/73 (98.6%) (mean ratio 1.71 +/- 0.28) KCT positive samples and normalized (mean ratio 1.03 +/- 0.16) after adding natural phospholipids to test plasma. The values expressed as SCT and KCT ratios were significantly correlated (r = .92; P < .001). SCT was normal in 40 healthy subjects utilised as controls (mean ratio 0.99 +/- 12). Sensitivity, specificity and diagnostic accuracy of SCT were 98.6%, 100% and 97.6%, respectively. Our data suggest that SCT is a sensitive test for detecting LA with a prolonged KCT in automated photooptical coagulometers. This peculiarity makes it particularly useful, in combination with diluted Russel viper venom time (dRVVT), for large-scale screening tests on LA.

High levels of antiphospholipid antibodies are associated with cytomegalovirus infection in unrelated bone marrow and cord blood allogeneic stem cell transplantation.

Antiphospholipid antibodies (APA) are a family of autoimmune and alloimmune immunoglobulins recognizing protein-phospholipid complexes in in vitro laboratory test systems. These antibodies have been associated with several conditions (malignancies, autoimmune diseases, infections, use of drugs); moreover, a syndrome capable of inducing thromboembolic disease has recently been associated with the presence of these antibodies. The aim of this prospective study was to investigate the levels of APA in subjects affected by haematological malignancies undergoing allogeneic haematopoietic stem cell transplantation (ASCT). Between March 1996 and December 1997, 32 patients undergoing ASCT were studied prospectively until day +180 from transplant. The mean values of IgG and IgM anticardiolipin antibodies (ACA) increased in recipients of stem cells from anunrelated donor, and a statistically significant difference inACA IgG mean value between unrelated and related transplanted patients was demonstrated between days +95 and +180. All of the subjects who received stem cells from an unrelated donor had APA levels higher than the mean normal value +3 SD vs. 35% of those receiving stem cells from a related donor (P < 0.01). The reason for such a difference may be a result of the different incidence in documented cytomegalovirus (CMV) infection in the two groups (83% vs. 23%; P < 0.01), as indicated by the significant correlation between APA positivity and CMV infection (P < 0.05). No relationship was found between APA, conditioning regimen and acute or chronic graft vs. host disease (GVHD). Moreover, we did not observe any thromboembolic disorder or veno occlusive disease (VOD).

The management of acute myelogenous leukemia in the elderly: ten-year experience in 118 patients.

This retrospective study was undertaken to analyse the survival pattern of 118 consecutive, unselected patients with acute myelogenous leukemia (AML) aged between 60 and 82 years observed at a single centre over a 10-year period (1981-1991). Thirty-two per cent of cases had an antecedent hematological disorder (AHD), and 7 per cent had a secondary AML. Forty patients (39 per cent) were managed with palliative intent with short courses with oral hydroxyurea +/- 6-thioguanine. In contrast to 78 patients (61 per cent) selected for remission-induction treatment, these were significantly older (P < 0.0001), had a greater incidence of AHD (P < 0.039) and of hypoplastic AML (P < 0.017), and an inferior amount of blast cells in the bone marrow (P < 0.003). Patients undergoing remission-induction chemotherapy were managed with DAT-like chemotherapy, high-dose cytosine arabinoside (HD-ara-C), and mitoxantrone-based regimens. The complete response (CR) rate was 29 per cent. Response was higher with the two most intensive HD-araC and mitoxantrone-etoposide-araC programmes (P < 0.026), and correlated favourably with no AHD (P < 0.04) and lower blast cell count in the peripheral blood (P < 0.02). Overall survival of responders was longer than in palliation and nonresponder groups (P < 0.025 and P < 0.001, respectively). In the active treatment group, survival correlated with performance status (P < 0.005) and blast cell count (P < 0.05). Infection was the main cause of morbidity during active treatment, accounting for most induction failures (60 per cent), followed by haemorrhage (12 per cent) and resistant disease (12 per cent). These results from an unselected series represent an improvement over those obtained by us in previous years (1971-1980), and show that intensive treatment programmes are applicable to the elderly with AML and that prolonged disease-free survival is possible for some. Improving further CR rate and duration will depend equally on the optimization of supportive care measures and the introduction of more effective therapeutic modalities.