Clinical view versus guideline adherence in ferritin monitoring and initiating iron chelation therapy in patients with myelodysplastic syndromes.

OBJECTIVES: In patients with myelodysplastic syndromes (MDS) with >20 transfusions and ferritin levels >1000 µg/L, international guidelines recommend iron chelation therapy (ICT). The study's objective was to determine guideline adherence and the intensity of ferritin monitoring in clinical practice. METHODS: We performed an observational population-based study using the HemoBase Registry, which contains data of all MDS patients diagnosed since 2005 in Friesland, the Netherlands. Clinical information on transfusions, ferritin measurements, ICT, and clinical performance as defined by age ≤ 80 years, Charlson Comorbidity Index <2 and lower-risk MDS was collected from health records. RESULTS: Two hundred and thirty seven of 292 patients (81.1%) received ≥1 transfusion, and 121 (41.4%) received >20 transfusions. In 57 of these 121 patients (47.1%), ferritin measurements were performed at least once. Clinical performance was significantly associated with monitoring ferritin around the 20th transfusion (RR: 2.49, p = .016). Clinical performance was also associated with initiating ICT (RR: 5.99, p < .001). ICT was offered to 22.3% (n = 25) of eligible patients. CONCLUSIONS: In this population-based study, ferritin levels were measured in <50% of MDS patients who received >20 transfusions, and clinical performance was significantly associated with measuring ferritin. Our study suggests that in heavily transfused MDS patients, ferritin monitoring is primarily based on patients' clinical performance rather than guideline recommendations.

A clinical effect of disease-modifying treatment on alloimmunisation in transfused patients with myelodysplastic syndromes: data from a population-based study.

BACKGROUND: Alloimmunisation against blood products is an adverse event, causing time-consuming compatibility testing. Current literature has not yet identified the influence of treatment on the risk of alloimmunisation in patients with myelodysplastic syndromes (MDS). MATERIALS AND METHODS: An observational, population-based study, using the HemoBase registry, was performed including all transfused patients who were diagnosed with MDS between 2005 and 2017 in Friesland, a province in the Netherlands. Information about transfusion dates, types, and treatment regimens was collected from the health records. Blood products were matched for ABO and Rhesus D. The effect of disease-modifying treatment was estimated with incidence rates and a Cox time-dependent analysis. RESULTS: 233 patients were included in this study, with a median follow-up of 13.0 months. Alloimmunisation occurred in 21 patients (9.0%) and predominantly occurred early in follow-up. Three (5%) and 18 (11%) alloimmunisation events occurred in patients with and without disease-modifying treatment, respectively. The hazard ratio for alloimmunisation without treatment compared to during treatment was 2.7 (95% CI: 0.35-20.0), with incidence rates of 7.18 and 2.41 per 100 patient-years, respectively. DISCUSSION: In a non-selected real-world population of MDS patients receiving blood transfusions, the percentage of patients with alloimmunisation was below 10%. The results of this study support the hypothesis that disease-modifying treatment affects the ability of the immune system to mount an antibody response to non-self blood group antigens.

Patterns of transfusion burden in an unselected population of patients with myelodysplastic syndromes: A population-based study.

BACKGROUND: Ineffective hematopoiesis in patients with myelodysplastic syndromes (MDS) often results in transfusion dependence. The burden of frequent transfusions in the real-world MDS population is largely unknown. STUDY DESIGN AND METHODS: An observational, retrospective, population-based study, using the HemoBase registry, was performed including all patients diagnosed with MDS between 2005 and 2017 in Friesland, a province in the Netherlands with approximately 650,000 inhabitants. Detailed clinical information was collected from the electronic health records. Transfusion burden was classified according to the International Working Group 2018 criteria: not transfusion dependent, low (LTB), or high transfusion burden (HTB). Univariate and multivariable regression analyses were performed. RESULTS: Of 292 patients, 136 (46.6%) had a HTB of ≥8 units/16 weeks and 17 (5.8%) had a LTB of 3-7 units/16 weeks. This was present in all types of MDS patients, but patients aged 75-84 years (odds ratio [OR] 4.02, 95% confidence interval [CI]: 1.84-8.82), high-risk MDS patients (OR 2.88, 95% CI: 1.08-7.68) and MDS-EB-2 patients (OR 7.07, 95% CI: 2.17-22.90) were particularly at risk for a HTB. DISCUSSION: This study provides a reliable estimate of the transfusion burden in real-world MDS patients, with almost half of the patients having a HTB. A HTB was observed in all MDS subtypes and both low- and high-risk MDS. Therefore, we conclude that the entire MDS population might benefit from novel agents that reduce the transfusion need and that might have beneficial effects on patient outcomes and healthcare utilization outcomes.

Reference values of fetal erythrocytes in maternal blood during pregnancy established using flow cytometry.

The aim of our study was to assess the fetal RBC count in maternal blood during uncomplicated pregnancies from 26 weeks onward. We used a flow cytometric method specifically designed for use in a routine hematology analyzer. Pregnant women were recruited through midwives. The participating laboratories used the FMH QuikQuant method (Trillium Diagnostics, Brewer, ME) in a CELL-DYN Sapphire hematology analyzer (Abbott Diagnostics, Santa Clara, CA). The method is based on a monoclonal antibody to hemoglobin F. Flow cytometric data were analyzed by 2 independent observers. The 95th percentile reference range was estimated according to Clinical and Laboratory Standards Institute guidelines. A total of 236 samples were statistically analyzed. Gestational ages ranged from 21.6 to 41 weeks (mean, 32.0 weeks), and the fetal RBC count in maternal blood ranged from 0.00% to 0.50% (median, 0.025%). The fetal RBC count in maternal blood shows no correlation with gestational age. The established reference range during normal pregnancy is less than 0.125%.