Autori: Tiscia G (1), Cappucci F (1), Scalzulli P (1), Cascavilla N (1), Battista C (2), Abrescia A (3), Aucella F (1), Buquicchio C (3), Brigante M (4), D’Andrea G (5), Di Paolo B (6), Giordano G (4), Infante B (5), Piano S (3), Ranieri P (2), Tullo L (4), Ostuni A (2), Grandone E (1)
Affiliazioni: (1) IRCCS “Casa Sollievo della Sofferenza”, San Giovanni Rotondo; (2) Azienda Ospedaliero-Universitaria Consorziale Policlinico di Bari, Bari; (3) Ospedale “Mons. Dimiccoli”, Barletta; (4) Ospedale “A. Cardarelli”, Campobasso; (5) Azienda Ospedaliera Universitaria Riuniti, Foggia; (6) Ospedale “San Pio da Pietrelcina”, Vasto;
Background We evaluated the diagnostic performance of PLASMIC score in patients consecutively referred to our Unit. Patients and methods From 2012 to 2017, we tested ADAMTS13 in 42 patients diagnosed with TMA. Clinical and laboratory data referred to time of blood drawn for ADAMTS13 testing were available for 25 of them. The score evaluates 7 parameters (1 point each):-platelet count<30×109/L, -hemolysis variables (reticulocyte count >2.5%, undetectable haptoglobin, or indirect bilirubin>2 mg/dL), -no active cancer, -no history of cell transplant, -mean corpuscular volume (MCV)<90 fL, -INR<1.5, and -creatinine level<2 mg/dL. Scoring system define low (0-4), intermediate (5), and high (6-7) likelihood of ADAMTS13<10%. A ROC curve was generated and the Area Under Curve (AUC) was calculated to test the discrimination value. Results The score showed a good discrimination performance with a resulting Area Under Curve (AUC) of 0.89 (95%CI 0.76-1.00; p=0.008). According to the model, we observed 6 patients in the low risk group, 4 and 17 in the intermediate and high-risk group, respectively. No severe deficiency was found in any case in the low-risk group, whereas a severe deficiency was found in 2 out of 4 intermediate-risk group and in 16 out of 17 high -risk group. In the low-intermediate risk group (0-5), we observed 2 short-term (within 1 week after the disease onset) deaths, in 2 patients with severe sepsis. All 27 patients were treated by Plasma EXchange (PEX) and steroids. Nine patients [4 with a refractory TTP and 3 with relapsed TTP] were also treated by rituximab. We found a TTP relapse in 3 (1 with score of 5) severely-deficient patients: in 2 of them (score= 6), who were diagnosed with cancer (pancreatic and myeloproliferative neoplasm), a long-term death occurred. Conclusions In our patients PLASMIC score has a good predictive value of the pretest likelihood of a severe ADAMTS13 deficiency. Further research is needed to confirm present data.