Multiparametric Flow Cytometry for MRD Monitoring in Hematologic Malignancies: Clinical Applications and New Challenges.

Along with the evolution of immunophenotypic and molecular diagnostics, the assessment of Minimal Residual Disease (MRD) has progressively become a keystone in the clinical management of hematologic malignancies, enabling valuable post-therapy risk stratifications and guiding risk-adapted therapeutic approaches. However, specific prognostic values of MRD in different hematological settings, as well as its appropriate clinical uses (basically, when to measure it and how to deal with different MRD levels), still need further investigations, aiming to improve standardization and harmonization of MRD monitoring protocols and MRD-driven therapeutic strategies. Currently, MRD measurement in hematological neoplasms with bone marrow involvement is based on advanced highly sensitive methods, able to detect either specific genetic abnormalities (by PCR-based techniques and next-generation sequencing) or tumor-associated immunophenotypic profiles (by multiparametric flow cytometry, MFC). In this review, we focus on the growing clinical role for MFC-MRD diagnostics in hematological malignancies-from acute myeloid and lymphoblastic leukemias (AML, B-ALL and T-ALL) to chronic lymphocytic leukemia (CLL) and multiple myeloma (MM)-providing a comparative overview on technical aspects, clinical implications, advantages and pitfalls of MFC-MRD monitoring in different clinical settings.

Monocyte Distribution Width (MDW) as novel inflammatory marker with prognostic significance in COVID-19 patients.

Monocyte Distribution Width (MDW), a new cytometric parameter correlating with cytomorphologic changes occurring upon massive monocyte activation, has recently emerged as promising early biomarker of sepsis. Similar to sepsis, monocyte/macrophage subsets are considered key mediators of the life-threatening hyper-inflammatory disorder characterizing severe COVID-19. In this study, we longitudinally analyzed MDW values in a cohort of 87 COVID-19 patients consecutively admitted to our hospital, showing significant correlations between MDW and common inflammatory markers, namely CRP (p < 0.001), fibrinogen (p < 0.001) and ferritin (p < 0.01). Moreover, high MDW values resulted to be prognostically associated with fatal outcome in COVID-19 patients (AUC = 0.76, 95% CI: 0.66-0.87, sensitivity 0.75, specificity 0.70, MDW threshold 26.4; RR = 4.91, 95% CI: 1.73-13.96; OR = 7.14, 95% CI: 2.06-24.71). This pilot study shows that MDW can be useful in the monitoring of COVID-19 patients, as this innovative hematologic biomarker is: (1) easy to obtain, (2) directly related to the activation state of a fundamental inflammatory cell subset (i.e. monocytes, pivotal in both cytokine storm and sepsis immunopathogenesis), (3) well correlated with clinical severity of COVID-19-associated inflammatory disorder, and, in turn, (4) endowed with relevant prognostic significance. Additional studies are needed to define further the clinical impact of MDW testing in the management of COVID-19 patients.

Universal Screening Program in Pregnant Women and Newborns at-Risk for Sickle Cell Disease: First Report from Northern Italy.

The implementation of screening programs for early detection of patients with sickle cell disease has become necessary in Italy as a result of the high rate of migration from areas with a high prevalence of the disease (Sub-Saharan Africa, Middle East and the Balkans). Following a pilot study performed in the province of Modena, Italy in 2011-2013, an official screening program was established on May 31 2014 for all pregnant women, free-of-charge for the family according to the National Guidelines for Physiological Pregnancy. Hemoglobin (Hb) profiles of pregnant women within 10 weeks of pregnancy, of new mothers at delivery and of the newborns of mothers with variant Hb profiles (newborns at-risk), were evaluated by high performance liquid chromatography (HPLC). Samples from 17,077 new mothers were analyzed and 993 showed alteration of Hb patterns (5.8%) (1.0% Hb AS carriers); of the 1011 at-risk newborns, four (0.4%) carried sickle cell disease and 90 (8.9%) were Hb AS carriers. These data show that early diagnosis of sickle cell disease or carrier status can be obtained in high-risk newborns, providing valuable information on the frequency of these conditions in geographic areas in which the disease is historically rare.

Sickle cell disease in areas of immigration of high-risk populations: a low cost and reproducible method of screening in northern Italy.

BACKGROUND: From 2005 to 2010, we observed a 10-fold increase of newly diagnosed sickle cell disease in children in the province of Modena (northern Italy). The median age at diagnosis was 24 months. Since these children are too old for optimal disease management, earlier detection of the disease is needed for prophylaxis and comprehensive care before the occurrence of clinical manifestations. MATERIALS AND METHODS: In each Maternity Unit of the province of Modena, blood samples are collected daily for assessment of haemolytic disease of the newborn. We designed a selective, low-cost haemoglobin screening for sickle cell disease in high-risk immigrants. We enrolled 469 mothers from sub-Saharan countries and their neonates for a primary screening of peripheral blood haemoglobin variants using high-performance liquid chromatography. RESULTS: Of the 469 women approached, 330 (70.36%) agreed to undergo the test. Ninety-two (27.88%) were carriers of variant haemoglobin, 48 newborns (51%) of these carriers had the carrier trait and 9 (9.6%) were affected (haemoglobin SC compound heterozigote - HbSC, haemoglobin S homozygote - HbSS). DISCUSSION: These results support the feasibility and usefulness of a selective screening for the detection of haemoglobin variants in high-risk subjects in an area in which sickle cells disease is not endogenous. We achieved the goal of detecting subjects with carrier trait/disease in order to implement preventive measures that reduce the clinical manifestations of sickle cell disease. We are, however, aware that it will be necessary to extend this screening to the overall population in the near future.