Background:Daratumumab is a human anti‐CD38 monoclonal antibody approved for the treatment of relapsed or refractory multiple myeloma (MM). Due to the physiological presence of the antigen CD38 on the red blood cell (RBC) membrane, Daratumumab (DARA) inteferes with the classical pre‐transfusion tests, impairing the identification of potential auto‐ or alloantibodies whenever present. The duration of this interference has been reported to be of 2‐6 months after the last DARA administration [Oostendorp M, Transfusion 2015].Aims:The present analysis aims at evaluating the duration of DARA‐related pre‐transfusion testing interference after the end of treatment at our Center, in order to better define an optimal strategy to assign compatible packed RBCs for transfusion therapy.Methods:According to our policy, all patients were typed for AB0, full Rh phenotype, K/k, direct/indirect antiglobulin tests and extended sierological RBCs typing before starting with DARA [2016 SIMTI recommendations]; the identification of compatible packed RBCs was obtained after crossmatching using dithiothreitol‐treated patient's blood sample.Results:From October 2017, a total of n = 7 MM patients received DARA at a median age of 68y (range: 50‐79); median number of previous therapeutic lines was 3 (range: 1‐7) and the median number of weekly administrations was 7 per patient (range: 1‐12). Two patients are still receiving DARA (1 and 12 administrations respectively). As expected, both direct and indirect antiglobulin tests were positive for all patients; moreover, one patient had also a well‐identified allo anti‐D antibody. Among the n = 5 ongoing patients, n = 4 are evaluable because they underwent the subsequent pre‐transfusion tests after the end of DARA treatment: n = 1 still presents interference 50 days after the end of DARA whereas interference disappeared in n = 3 patients at 48, 65 and 111 days after the last treatment.Summary/Conclusion:Our preliminary data confirm the persistence of DARA‐related pre‐transfusion testing interference after the end of treatment for a median period of 2 months in this cohort of MM patients treated at our Institution. Futher follow‐up and the analysis of additional patients in the next future will allow to better determine the duration of interference; we believe these data are worthy of note due to increasing use of DARA, even for other clinical situations [Chapuy CI, NEJM 2018; Kwun JEB, Am J Transplant 2017]

Background:The hemoglobin (Hb) value adopted in the real life setting for the clinical decision of packed red blood cell (RBC) transfusion (transfusion trigger) is sometimes difficult to accurately retrieve and could be different to what is indicated in the blood request. The identification of the transfusion trigger is critical for the analysis of the distinct physicians’ attitudes across the different units within the same hospital and for the dissection of transfusion appropriateness.Aims:The aims of the present analysis is to compare the transfusion trigger across the multiple medical and surgical units at our Center and to describe the Hb values before and after the transfusion events. Further, considerations about the feasibility and the potential applications of this analytical approach are discussed.Methods:Data extraction procedure focused on the first semester 2018, dealing with transfusion episodes of 1–2 packed RBCs administered to patients hospitalised at ASST GOM Niguarda, Milan, Italy. Each single episode was registered, regardless of the number of the total packed RBCs transfused, as well as the Unit where the patient was admitted and the Hb values at admission, before and after the transfusion, together with the respective date and time. Comparisons analyses were made using the classical statistical tests. The Hb value before the transfusion is considered as the trigger for transfusion decision by the physician(s) in charge of the patients.Results:On a total of n = 501 episodes, n = 497 were evaluable for completeness of data. The corresponding number of packed RBCs represents the 2% of all the packed RBCs transfused at our Hospital in one year (n = 22170 in 2018). Median Hb was 10.70 (range: 6.30–16.70), 8.60 (range:3.00–15.10) and 10.30 (range: 5.00–16.30) at admission, before and after transfusion, respectively. Analyzing separately by unit, we observed that the transfusion trigger was higher in Cardiac Surgery, Vascular Surgery and Intensive Care Units, with median values of 9.50, 8.75 and 8.70 respectively. Conversely, transfusion trigger was comparable among the other surgical units (including Orthopedics) and the medical ones: Hb median values were 8.20, 8.20 and 8.30 respectively. Cardiology showed a slightly higher trigger: 8.65 when compared with the other non‐surgical units.Summary/Conclusion:The present analysis, accounting for « only » the 2% of the total transfusion burden at our Hospital in 2018, allows for a satisfactory definition of the transfusion trigger across the multiple medical and surgical units as well as the confirmation of the expected post‐transfusion Hb values. Our analysis model supports the feasibility of such an approach as a potential audit instrument and intervention policies in the area.

Idiopathic recurrent acute pericarditis (IRAP) is suspected to be an autoimmune phenomenon. We studied 46 consecutive patients. We looked for: 1) the occurrence of new diagnoses of autoimmune diseases during our follow up; 2) HLA typing; and 3) the presence of the most frequent mutations linked to familial Mediterranean fever (FMF gene or MEFV). HLA typing was done in 21 patients at loci B, DRB1, DQA1 and DQB1. MEFV gene was looked in 23 patients using specific primers. During the follow-up we made a new diagnosis of primary Sjögren's syndrome in four patients (8.7%) and of rheumatoid arthritis in one patient (2.2%). HLA B14, DRB1*01 and DQB1*0202 were significantly more prevalent, but we did not find a typical HLA typing. MEFV gene was searched: exon 10 was checked by sequence and the E148Q mutation by restriction site analysis. No mutations were found. In conclusion, the prevalence of definite immunorheumatological diseases and the absence of the mutations linked to FMF reinforce the notion that idiopathic acute recurrent pericarditis is an autoimmune condition.