Focus on Key Issues in Immune Thrombotic Thrombocytopenic Purpura: Italian Experience of Six Centers.

Immune-mediated thrombotic thrombocytopenic purpura is a rare and challenging hematological disease caused by the antibody anti-ADAMTS13. Though the mortality rate has decreased considerably in recent years, fatalities still remain unacceptable. This study aimed at further adding to the existing knowledge of this medical challenge. We enrolled 89 consecutive patients observed in six Italian centers (from 8 August 2013 to 28 May 2021) with a diagnosis of immune-mediated thrombotic thrombocytopenic purpura. Clinical information and blood parameters were collected for all patients. We describe clinical manifestations and laboratory data, possible risk factors and the therapeutic management of first episodes or relapses. A total of 74 first episodes and 19 relapses (median 3 years (interquartile range (IQR): 2-7)) were recorded. Seventy percent of patients enrolled at the first episode showed neurological signs and/or symptoms. All the patients enrolled at the first episode were treated with plasma exchange (median = 12; IQR: 8-19.5) and methylprednisolone (1 mg/kg/day). Rituximab (375 mg/m2 weekly for four weeks) and caplacizumab were given to 15 (20.2%) and 2 patients (2.6%), respectively. We observed an overall mortality of 5.4% in the follow-up (median 60 months; IQR: 36.0-103.5). All fatalities occurred after a diagnostic delay. Present data point to the importance of the early detection of factors mostly associated with poor outcomes. It is likely that use of caplacizumab could improve the prognosis in those patients.

Validation of PLASMIC score and follow-up data in a cohort of patients with suspected microangiopathies from Southern Italy.

Severe ADAMTS13 deficiency (activity < 10%) is pathognomonic of thrombotic thrombocytopenic purpura. ADAMTS13 testing is time-consuming and unavailable in many hospitals. Recently, a seven-variables score named PLASMIC score, has been developed to stratify acute patients, based on their risk of having a severe ADAMTS13 deficiency. We present the application of this score in a cohort of patients referred to our Center. From 2012 to 2017, 42 patients with suspected thrombotic microangiopathies from 6 Centers were referred to Hemostasis and Thrombosis Center of "Casa Sollievo della Sofferenza" Hospital/Research Institute for ADAMTS13 testing. For all patients, relevant medical and laboratory information were collected. To obtain the statistical measure of the discriminatory power of PLASMIC scoring system, the Area Under the Curve Receiver Operating Characteristic (AUC ROC) was calculated. We were able to calculate the PLASMIC score in 27 out of 42 patients; we found a good discrimination performance of the score with a resulting AUC value of 0.86 (95% CI 0.71-1.0; p = 0.015). All patients but one with a high risk PLASMIC score (6-7) showed a severe deficiency. Among patients belonging to the intermediate risk (PLASMIC score 5) group, 2 showed normal ADAMTS13 activity and 2 levels below 10%. In none of the patients in the low risk group (PLASMIC score 0-4), a severe ADAMTS13 deficiency was found. Present results confirm and extend previous data regarding the predictive value of the PLASMIC score. Indeed, it shows a good diagnostic performance and can be useful for decision makers to properly and promptly define the better therapeutic approach.

Familial B-cell chronic lymphocytic leukemia in a population of patients from Southern Italy.

We investigated the prevalence of chronic lymphocytic leukemia (CLL) in 9650 relatives of 510 CLL patients from 5 different regions (Apulia, Basilicata, Campania, Calabria, and Sicily) of Southern Italy. Data collection included a family history questionnaire. In our series of 510 CLL patients, 53 families with 2 or more individuals who had chronic lymphoproliferative disease (CLD) or other hematological malignancies were identified. In these families, 27 cases of CLL, 10 of indolent non-Hodgkin's lymphoma, and 7 of multiple myeloma were identified in relatives of CLL probands. Twenty-two relatives developed hematological malignancies other than CLD (19, acute leukemia; 3, chronic myeloid leukemia). In this study the prevalence of CLD in relatives of 510 CLL patients was 8.6% (44/510), and the prevalence of CLL in the same series was 5.2% (27/ 510). Considering the presence of clusters of individuals with hematological malignancies, overall our series contained 4 families showing a cluster with more than 2 cases. The most frequent pattern of affected family members was represented by 39 families (39/53 [73%]) with affected siblings or cousins only. Twenty siblings had CLL. The other families showed a multigenerational pattern with an affected parent-offspring relationship in only 11 (21%) of the cases and with a combination of the first 2 categories in 3 (6%) of the families. In 8 families belonging to both the last 2 mentioned groups, the affected offspring had an earlier disease onset than their parents, suggesting anticipation. We estimated the size and examined the pattern of familial aggregation of hematological malignancies, in particular CLL/CLD, in a specific geographical area. CLL was the most frequent disease in relatives, mainly siblings, of our CLL patients. Our results may be a contribution to the characterization of the epidemiological distribution pattern of CLL.