Francesco Marongiu

Clinical course of high‐risk patients diagnosed with antiphospholipid syndrome

See also Galli M. The antiphospholipid triangle. This issue, pp 234–6.

Incidence of a first thromboembolic event in asymptomatic carriers of high-risk antiphospholipid antibody profile: a multicenter prospective study

Persistent antiphospholipid (aPL) antibodies are occasionally found in subjects without prior history of thromboembolic events (TEs), raising the dilemma of whether to initiate or not a primary thromboprophylaxis. A first TE is considered rare in aPL carriers, but previous studies did not consider the aPL profile nor was the test positivity confirmed in a reference laboratory. In this study, 104 subjects with high-risk aPL profile (positive lupus anticoagulant, anticardiolipin, and anti-β(2)-glycoprotein I antibodies, triple positivity) confirmed in a reference laboratory, were followed up for a mean of 4.5 years. There were 25 first TEs (5.3% per year): the cumulative incidence after 10 years was 37.1% (95% confidence interval [CI], 19.9%-54.3%). On multivariate analysis, male sex (hazard ratio = 4.4; 95% CI, 1.5-13.1, P = .007) and risk factors for venous thromboembolism (hazard ratio = 3.3; 95% CI, 1.3-8.5, P = .01) were independent predictors for TEs. Aspirin did not significantly affect the incidence of TE. In conclusion, the occurrence of a first TE in carriers of high-risk aPL profile is considerable; it is more frequent among male subjects and in the presence of additional risk factors for venous TE. These data can help in the decision to initiate primary thromboprophylaxis in these subjects.

Questions and answers on the use of dabigatran and perpectives on the use of other new oral anticoagulants in patients with atrial fibrillation: A consensus document of the Italian Federation of Thrombosis Centers (FCSA)

Dabigatran and other new oral anticoagulants (OAC) represent a step forward in stroke prevention in patients with atrial fibrillation (AF). They indeed have been shown to be an alternative to vitamin K antagonists (VKAs) without the burden of laboratory control. However, these new drugs compete with an effective and well-established therapy, thus bringing about a series of questions and doubts. In this report members of the board of the Italian Federation of Thrombosis Centers (FCSA) answer some questions every clinician might be confronted with.

Usefulness of repeated D-dimer testing after stopping anticoagulation for a first episode of unprovoked venous thromboembolism: the PROLONG II prospective study

The PROLONG randomized trial showed that a normal D-dimer (D-d) 1 month after anticoagulation suspension for unprovoked venous thromboembolism (VTE) was associated with a low risk of late recurrences (4.4% patient years). However, it is unknown whether D-d changes subsequently. The aim of this prospective multicenter study was to assess D-d time course and its relation with late recurrences in patients with normal D-d 1 month after anticoagulation suspension for a first episode of unprovoked VTE. D-d was measured with a qualitative method (Clearview Simplify D-dimer; Inverness Medical Professional Diagnostics). Patients with a normal D-d 1 month after stopping anticoagulation repeated D-d testing every 2 months for 1 year. D-d was normal in 68% (243/355) of patients 1 month after anticoagulation suspension. Patients in whom D-d became abnormal at the third month and remained abnormal afterward had a higher risk of recurrence (7/31; 27% patient years; 95% confidence interval [CI]: 12-48) than patients in whom D-d remained normal at the third month and afterward (4/149; 2.9% patient years; 95% CI: 1-7; adjusted hazard ratio: 7.9; 95% CI: 2.1-30; P = .002). Repeated D-d testing after anticoagulation suspension for a first episode of unprovoked VTE could help tailor the duration of treatment. This trial is registered at http://clinicaltrials.gov as NCT00266045.

Uneven hepatic iron and phosphorus distribution in beta-thalassemia

BACKGROUND/AIMS Determination of hepatic iron concentration is crucial in the evaluation of iron-storage disease. Iron content is normally determined in a part of a needle liver biopsy and the value obtained is considered to be representative of the iron concentration in the whole liver. To evaluate the reliability of this procedure, we studied iron distribution in the liver of two beta-thalassemic patients. Since the transport of intracellular iron is mediated by phosphates, we also studied the hepatic phosphorus distribution. METHODS At autopsy, a liver slice extending from the left to the right lobe was divided into 51 and 49 samples, respectively. Each specimen was subdivided into two parts: one of them was paraffin-embedded and utilized for the histochemical detection of iron; the second part was analyzed for iron and phosphorus content by induced coupled plasma atomic emission spectroscopy. RESULTS The histological picture of both livers was characterized by portal and periportal fibrosis associated with iron storage of different degree, without cirrhosis. The mean iron concentration of the liver was 20,631 +/- 4903 micrograms per g of dry tissue (micrograms/g dt) and 13,901 +/- 1976 micrograms/g dt, respectively. A striking variability in iron content between samples was also found: iron concentration ranged from 11,537 to 32,347 micrograms/g dt in the first case and from 6257 to 16,493 in the second case. We even observed regional differences in iron concentration, with a preferential peripheral accumulation in both cases and a tendency of the left compartment of the liver to accumulate more iron in the first case. Histochemical analyses confirmed the uneven iron distribution even at the acinar level, showing iron mainly being stored in hepatocytes and Kupffer cells of zone 1 of the acinus, with decreasing amounts of iron in zones 2 and 3. The mean hepatic phosphorus concentration was 6662 +/- 1300 micrograms/g dt (range: 4348-9947) and 7502 +/- 986 micrograms/g dt (range: 5844-90,282), respectively. The regional distribution of phosphorus was similar to that observed for iron. A strict correlation between iron and phosphorus content was also observed. CONCLUSIONS Our data show that: 1) iron and phosphorus are unevenly distributed in the beta-thalassemic liver, even in the non-cirrhotic stages; 2) a regional pattern of iron and phosphorus distribution is evident, characterized by higher concentrations at the periphery of the liver; 3) the observed uneven distribution of iron and phosphorus implies that their content determined in a small liver sample cannot be considered as absolutely representative of the mean hepatic iron concentration. Therefore, iron concentrations determined in a part of a needle liver biopsy should be interpreted with caution in monitoring the efficacy of the iron-chelating therapy in beta-thalassemic patients.

Survey of lupus anticoagulant diagnosis by central evaluation of positive plasma samples.

Summary.  Objective: To determine whether the diagnosis of lupus anticoagulant (LAC) in a large cohort of positive patients was confirmed at a reference laboratory. Methods: Over a 1‐year period, each participating center collected samples from LAC‐positive patients. Plasma was filtered and kept deep‐frozen until it was sent on dry ice to the reference laboratory by express courier. Centers returned detailed laboratory information and clinical data from each patient. The reference laboratory screened plasma samples by diluted Russell viper venom time (dRVVT) and kaolin clotting time (KCT). When these were prolonged, 1:1 mixing studies were carried out, and confirmatory tests were performed as appropriate. Positive samples were further tested by thrombin time (TT). The presence of heparin was checked by measuring antifactor Xa activity when TT was prolonged. Negative samples were tested by activated partial thromboplastin time using hexagonal phospholipids. Results: Plasma samples from 302 patients from 29 anticoagulation clinics were analyzed. LAC was excluded in 71 samples (24%), because dRVVT and KCT screening test results were normal (34) or reversed to normal by mixing studies (35). The remaining two samples were considered negative because they contained heparin. LAC‐negative patients showed different characteristics from those in whom diagnosis was confirmed. They were significantly older (49.7 vs. 45.0 years, P < 0.03), were more often first diagnosed (66% vs. 41%, P < 0.001), and were more frequently judged as mild in LAC potency (60% vs. 25%, P < 0.0001). Moreover, anticardiolipin and anti‐β2‐glycoprotein I antibody values were more often normal in LAC‐negative (82%) than in LAC‐positive (42%) samples (P < 0.0001). LAC‐positive samples identified by both dRVVT and KCT (146/231, 63%) showed a LAC potency that was significantly stronger than that in samples in which LAC diagnosis was made by a single test. Conclusions: A false‐positive LAC diagnosis is not uncommon across specialized centers. Patients’ characteristics and a complete antiphospholipid antibody profile may help to identify these individuals.

Controlled Vitamin K Content Diet for Improving the Management of Poorly Controlled Anticoagulated Patients: A Clinical Practice Proposal

The aim of our study was to investigate the effect of a diet with a known vitamin K content on the monitor test for oral anticoagulant therapy. We studied 10 poorly controlled patients (7 women and 3 men, mean age 48 +/- 15 years) in therapy with acenocoumarol for at least 1 year. Another group of 10 poorly controlled patients was considered as a control group. After a baseline period, during which a free diet was allowed, patients were administered a diet with a controlled vitamin K content; in the same period, control subjects were not subjected to any dietary restriction. Thrombotest (Nyegaard, Oslo) was employed for monitoring oral anticoagulant therapy, with a therapeutic range between 2.3 and 4.8 INR. We found a significant difference by thrombotest between the percentages within the therapeutic range obtained before and during dietary treatment (p = 0.0001). The difference in percentages was -0.31 and the 95% CI, of the difference ranged from -0.45 to -0.17. No significant difference was shown in the control group in the same periods. Our data suggest that a diet with a controlled vitamin K content is effective in increasing the percentage of tests within the therapeutic range in patients with poorly controlled anticoagulation.

A Comparison of Lupus Anticoagulant–Positive Patients With Clinical Picture of Antiphospholipid Syndrome and Those Without

Among antiphospholipid antibodies, Lupus Anticoagulant (LAC) is recognized as the strongest risk factor for thromboembolic events or pregnancy morbidity.1 The presence of LAC in a subject with previously documented thromboembolism or a significant history of pregnancy loss defines the Antiphospholipid Syndrome (APS). Some patients, however, are diagnosed with LAC without ever having experienced previous vascular thrombosis or pregnancy morbidity. The antiphospholipid antibody profiles of LAC positive patients with or without associated clinical features of APS have been evaluated by us in a multicenter study. Centers affiliated with Italian Federation of Thrombosis Centers (FCSA) were invited to identify consecutive LAC positive patients diagnosed over a 1-year period. Three hundred twenty-one recruited patients were contacted and after giving informed consent they underwent testing for LAC after at least 12 weeks from the first one using routine laboratory procedures. LAC was not confirmed by Thrombosis Centers in 19 patients (6 were …

Fibrinogen and fibrinolytic activity in hyperthyroidism before and after antithyroid treatment

Plasma concentration of fibrinogen and Bβ 15–42, a specific product of fibrinogen metabolism induced by plasmin, were measured in a group of patients with untreated hyperthyroidism and in controls. Significantly increased plasma levels of both parameters were observed in hyperthyroid patients. The restoration of euthyroidism either by antithyroid drug or by radioiodine caused a significant decrease of fibrinogen and Bβ15–42. These data indicate that hyperthyroidism is another clinical condition associated with increased concentration of fibrinogen and Bβ 15–42.

α2antiplasmin and disseminated intravascular coagulation in liver cirrhosis

Subnormal concentrations of alpha 2 Antiplasmin (alpha 2 AP) in liver cirrhosis may be due to an impaired hepatic synthesis and/or to a fibrinolysis activation in disseminated intravascular coagulation (DIC). In order to clarify this problem, in 26 cirrhotic patients (15 compensated and 11 decompensated) alpha 2 AP plasma activity and plasma Fibrinopeptide A (FPA) were measured. Serum albumin, p-Cholinesterase (p-CHE), Fibrinogen and Fibrinogen Degradation Products (FDP) were also carried out. Our data show that alpha 2 AP and FPA were equally abnormal in compensated and decompensated cirrhosis. The significant negative correlation obtained between alpha 2 AP and FPA as well as the lack of correlation between alpha 2 AP and albumin, alpha 2 AP and p-CHE in both groups suggests that, in our patients, alpha 2 AP decrease may be due to a fibrinolysis activation induced by a DIC which appears chronic since Fibrinogen and FDP were normal. These findings are in agreement with the results obtained in the four subgroups a posteriori selected on the basis of FPA levels: alpha 2 AP in subgroups with high FPA was significantly different from controls while it did not differ in subgroups with normal FPA.