Early Diagnosis of 46,XX Testicular Difference of Sexual Development: Unusual Presentation with Increased Nuchal Translucency.

INTRODUCTION: 46,XX testicular disorder of sexual development (DSD) may present prenatally as a mismatch between phenotype and karyotype. Enlarged nuchal translucency is an abnormal sign of many disorders. We present a first trimester fetus with increased nuchal translucency that was later determined to be a 46,XX testicular DSD. CASE PRESENTATION: A first-trimester pregnancy ultrasound revealed enlarged nuchal translucency. Chorionic villous sampling documented a 46,XX karyotype. Subsequent ultrasounds identified male external genitalia. FISH analysis documented a SRY gene translocation. At birth, the infant had normal male internal and external genitalia. CONCLUSIONS: 46,XX testicular DSD may present in the first trimester with an enlarged nuchal translucency.

Acute hospitalization in a cohort of patients with systemic sclerosis: a 10-year retrospective cohort study.

This study aimed at analysing the causes and predictors of acute hospitalization and mortality in a cohort of SSc. Retrospective analysis of all acute hospital admissions of SSc patients fulfilling the 2013 EULAR/ACR Classification Criteria, from a single-centre cohort of 95 patients, between 2010 and 2020. The total number of SSc patients registered in our hospital, in this period, was 123. Clinical data were collected from medical files of our institution and from the National Healthcare Registry platform. 53 patients needed acute hospitalization, in a total of 164 admissions. The most frequent causes for admission were: infectious diseases [27%; 70% due to pneumoniae, of which 74% had SSc-associated interstitial lung disease (ILD)], cardiac disease (16.5%), peripheral vascular disease [12.8%; all due to digital ulcers], pulmonary hypertension (PH) (9.8%) and ILD (9.1%). There was an increase in admissions due to cardiac disease over the 10 years of follow-up, and a decrease of ILD over the last 5 years. Fourteen patients died (in-hospital mortality of 9%) mainly due to pneumoniae (36%), heart failure (21%), neoplastic diseases (21%), PH (14%) and ILD (7%). From all the admissions due to infection 70.5% were under immunosuppression at the time of the hospitalization. The frequency of acute admissions superior to 1 was associated with infection (OR 2.29, 95%CI 1.11-4.71). There were several factors associated with both acute admissions and mortality, including: gender, race, digital ulcers, cardiac dysfunction, ILD and PH. Infection was the principal cause of acute hospitalization and mortality, mainly due to pneumoniae. Although a high percentage of those had ILD, it has been decreasing in the last years in our cohort, as a direct cause of hospital admission and mortality, possibly reflecting the advances in its management.

Automated identification of leukocyte subsets improves standardization of database-guided expert-supervised diagnostic orientation in acute leukemia: a EuroFlow study.

Precise classification of acute leukemia (AL) is crucial for adequate treatment. EuroFlow has previously designed an AL orientation tube (ALOT) to guide toward the relevant classification panel and final diagnosis. In this study, we designed and validated an algorithm for automated (database-supported) gating and identification (AGI tool) of cell subsets within samples stained with ALOT. A reference database of normal peripheral blood (PB, n = 41) and bone marrow (BM; n = 45) samples analyzed with the ALOT was constructed, and served as a reference for the AGI tool to automatically identify normal cells. Populations not unequivocally identified as normal cells were labeled as checks and were classified by an expert. Additional normal BM (n = 25) and PB (n = 43) and leukemic samples (n = 109), analyzed in parallel by experts and the AGI tool, were used to evaluate the AGI tool. Analysis of normal PB and BM samples showed low percentages of checks (<3% in PB, <10% in BM), with variations between different laboratories. Manual analysis and AGI analysis of normal and leukemic samples showed high levels of correlation between cell numbers (r2 > 0.95 for all cell types in PB and r2 > 0.75 in BM) and resulted in highly concordant classification of leukemic cells by our previously published automated database-guided expert-supervised orientation tool for immunophenotypic diagnosis and classification of acute leukemia (Compass tool). Similar data were obtained using alternative, commercially available tubes, confirming the robustness of the developed tools. The AGI tool represents an innovative step in minimizing human intervention and requirements in expertise, toward a "sample-in and result-out" approach which may result in more objective and reproducible data analysis and diagnostics. The AGI tool may improve quality of immunophenotyping in individual laboratories, since high percentages of checks in normal samples are an alert on the quality of the internal procedures.

Nailfold Videocapillaroscopy Changes Are Associated With the Presence and Severity of Systemic Sclerosis-Related Interstitial Lung Disease.

OBJECTIVE: The aim of this study was to evaluate the association of nailfold videocapillaroscopy (NVC) changes and the presence and severity of interstitial lung disease (ILD) in systemic sclerosis. METHODS: This was a cross-sectional analysis of 48 systemic sclerosis patients (21 patients with ILD). The NVC characteristics considered were capillary organization, capillary loss (CL), avascular areas, enlarged and giant capillaries, hemorrhages, abnormally shaped capillaries, edema, and intermittent flux.We analyzed the association between NVC findings and (1) presence and extension of ILD and (2) percent predicted of forced vital capacity (FVC) and the carbon monoxide diffusing capacity (DLCO). RESULTS: Capillary loss and avascular areas showed a significant association with the presence of ILD (odds ratio, 18.57; 95% confidence interval [CI], 2.17-158.72 [p = 0.008]; and odds ratio, 4.64; 95% CI, 1.35-15.91 [p = 0.015], respectively). Receiver operating characteristic (ROC) curve analysis confirmed the association between CL and ILD (area under the ROC curve, 90.1%; 95% CI, 81.8-91.4). Avascular areas and CL were associated with a worse pulmonary function (FVC -18.1% [p = 0.034], DLCO -14.0% [p = 0.013]; and FVC -15.3% [p = 0.086], DLCO -12.3% [p = 0.049], respectively). No association was found between other NVC findings and ILD or lung function. CONCLUSIONS: Capillary loss and avascular area showed a significant association with the presence of ILD, supported by ROC curve analysis. These results may reinforce a prognostic role for NVC and a physiopathology mechanism for ILD based on vascular damage.

Quality assessment program for EuroFlow protocols: summary results of four-year (2010-2013) quality assurance rounds.

Flow cytometric immunophenotyping has become essential for accurate diagnosis, classification, and disease monitoring in hemato-oncology. The EuroFlow Consortium has established a fully standardized "all-in-one" pipeline consisting of standardized instrument settings, reagent panels, and sample preparation protocols and software for data analysis and disease classification. For its reproducible implementation, parallel development of a quality assurance (QA) program was required. Here, we report on the results of four consecutive annual rounds of the novel external QA EuroFlow program. The novel QA scheme aimed at monitoring the whole flow cytometric analysis process (cytometer setting, sample preparation, acquisition and analysis) by reading the median fluorescence intensities (MedFI) of defined lymphocytes' subsets. Each QA participant applied the predefined reagents' panel on blood cells of local healthy donors. A uniform gating strategy was applied to define lymphocyte subsets and to read MedFI values per marker. The MedFI values were compared with reference data and deviations from reference values were quantified using performance score metrics. In four annual QA rounds, we analyzed 123 blood samples from local healthy donors on 14 different instruments in 11 laboratories from nine European countries. The immunophenotype of defined cellular subsets appeared sufficiently standardized to permit unified (software) data analysis. The coefficient of variation of MedFI for 7 of 11 markers performed repeatedly below 30%, average MedFI in each QA round ranged from 86 to 125% from overall median. Calculation of performance scores was instrumental to pinpoint standardization failures and their causes. Overall, the new EuroFlow QA system for the first time allowed to quantify the technical variation that is introduced in the measurement of fluorescence intensities in a multicentric setting over an extended period of time. EuroFlow QA is a proficiency test specific for laboratories that use standardized EuroFlow protocols. It may be used to complement, but not replace, established proficiency tests. © 2014 International Society for Advancement of Cytometry.

What have we learned on pre, very early, and early systemic sclerosis microcirculatory pathophysiology? A scoping review.

OBJECTIVE: Microvascular dysfunction is an early event in the pathogenesis of systemic sclerosis (SSc). The objective of this scoping review is to update the current information and the level of knowledge about the mechanisms of microvascular dysfunction in pre-SSc, very early diagnosis of SSc (VEDOSS) and early SSc. METHODS: A PubMed® database search allowed us to include original data from full-length articles in English in which the main topic was microvascular dysfunction in pre-SSC, VEDOSS or early SSc. Data was extracted using a customized form. RESULTS: In the present review 437 articles were identified, and 42 studies included, reporting data from a total of 1069 patients with pre-SSc, VEDOSS or early-SSc. Distinct mechanisms of microvascular injury were identified comprising, angiogenesis and vasculogenesis, cell surface proteins and adhesion, molecules expression, cytokines profile, inflammatory and oxidation pathways, and skin perfusion determinants. Most of the studies were conducted in early SSc, with a reduced number in pre-disease stages, in which the prompt recognition of specific mechanisms and biomarkers may allow targeted treatment to prevent disease progression. CONCLUSIONS: Although different molecular expression patterns and signaling pathways related to microvascular dysfunction in pre-SSc, VEDOSS, and early SSc were identified, additional prospective longitudinal studies and combined work with functional evaluation of peripheral skin perfusion are needed.

Differentiated Thyroid Cancer in Children and Adolescents: 12-year Experience in a Single Center.

Objective: Differentiated thyroid cancer (DTC) is the most common pediatric endocrine cancer but studies are scarce. Latest recommendations advocate for an individualized risk-based approach to select patients for additional therapy. Lymphovascular invasion is not considered, despite being a well-known risk factor in the adult population. The aim of our study was to describe the outcomes of a cohort of DTC patients diagnosed at pediatric age and to evaluate the impact of lymphovascular invasion on the risk of persistence/recurrence. Methods: We conducted a retrospective study of patients diagnosed with DTC at pediatric age from 2010 to 2022 at our center. All patients had total thyroidectomy. Radioactive iodine therapy (RAI) was used in selected patients. The response to therapy and occurrence of persistent/recurrent disease were evaluated. Results: A total of 21 DTC were diagnosed, mostly papillary thyroid carcinoma (PTC) (81.0%, 17). Six patients (28.6%) had nodal involvement and one (4.8%) had lung metastasis at the time of the diagnosis. Lymphovascular invasion was present in 11 patients (52.4%). After surgery, 13 patients (61.9%) were submitted to RAI. The mean follow-up time was 5.7 ± 3.1 years. Overall, 6 patients (31.6%) experienced persistent/recurrent disease during the follow-up time. Among PTC patients, persistent/recurrent disease was more frequent in the presence of lymphovascular invasion [55.6% (5/9) vs 0.0% (0/6), p=0.031]. Conclusion: An individualized risk-based approach is recommended. Our study suggests that lymphovascular invasion may be associated with a higher risk of persistence/recurrence and should therefore be considered for decision making in children and adolescents with PTC.

Re-evaluation of nailfold capillaroscopy in discriminating primary from secondary Raynaud's phenomenon and in predicting systemic sclerosis: a randomised observational prospective cohort study.

BACKGROUND: Primary Raynaud's phenomenon (pRP) is difficult to distinguish from secondary (sRP). Although nailfold capillaroscopy (NFC) may detect early alterations, no universal criteria yet discriminate between pRP from sRP. OBJECTIVES: To create and validate two NFC scores that could distinguish pRP from sRP and that could predict systemic sclerosis (SSc), respectively. METHODS: We performed NFC on two separate cohorts with isolated RP, and recorded number of capillaries per field, enlarged/giant capillaries, crossed/bizarre patterns, microhemorrhages, neoangiogenesis, rarefaction, edema, blood flow velocity, stasis. By multivariate regression analysis, we evaluated the adjusted prognostic role of these features in a derivation cohort of 656 patients. Results were used to construct algorithm-based prognostic scores (A and B). These scores were then tested on a confirmation cohort of 219 patients. RESULTS: Score A was unable to discriminate sRP from pRP (low negative predictive values with high positive predictive values for any cut-point); score B was unable to discriminate progression to SSc or a SSc-spectrum disorder (low positive predictive values with high negative predictive values for lower cut-points). CONCLUSION: NFC patterns, believed as specific, showed low discriminatory power and on their own are unable to reliably discriminate sRP from pRP or predict evolution to SSc.

Studying Erythromelalgia Using Doppler Flowmetry Perfusion Signals and Wavelet Analysis-An Exploratory Study.

Erythromelalgia (EM) is a rare disease, which is still poorly characterized. In the present paper, we compared the hand perfusion of one female EM patient, under challenges, with a healthy control group. Using a laser Doppler flowmeter (LDF) with an integrated thermal probe, measurements were taken in both hands at rest (Phase I) and after two separate challenges-post-occlusive hyperemia (PORH) in one arm (A) and reduction of skin temperature (cooling) with ice in one hand (B) (Phase II). The final measurement periods corresponded to recovery (Phases III and IV). The control group involved ten healthy women (27.3 ± 7.9 years old). A second set of measurements was taken in the EM patient one month after beginning a new therapeutic approach with beta-blockers (6.25 mg carvedilol twice daily). Z-scores of the patient's LDF and temperature fluctuations compared to the control group were assessed using the Wavelet transform (WT) analysis. Here, fluctuations with |Z| > 1.96 were considered significantly different from healthy values, whereas positive or negative Z values indicated higher or lower deviations from the control mean values. Cooling elicited more measurable changes in LDF and temperature fluctuations, especially in higher frequency components (cardiac, respiratory, and myogenic), whereas PORH notably evoked changes in lower frequency components (myogenic, autonomic, and endothelial). No significant Z-score deviations were observed in the second measurement, which might signify a stabilization of the patient's distal perfusion following the new therapeutic approach. This analysis involving one EM patient, while clearly exploratory, has shown significant deviations in WT-derived physiological components' values in comparison with the healthy group, confirming the interest in using cold temperature as a challenger. The apparent agreement achieved with the clinical evaluation opens the possibility of expanding this approach to other patients and pathologies in vascular medicine.

Hyperthyroidism in McCune-Albright Syndrome - a case report.

OBJECTIVES: We intend to describe a case of McCune-Albright Syndrome (MAS), a rare disease characterized by fibrous dysplasia (FD), cutaneous hyperpigmentation and hyperfunctioning endocrinopathies (HFE). CASE PRESENTATION: We report the case of a 13-year-old male child who presented with a café-au-lait macule in the lumbosacral region and disabling polyostotic FD, requiring several surgical interventions and bisphosphonates from the age of 3 years (Y) + 9 months (M) due to persistent and severe pain. Hyperthyroidism (HT) became apparent at 5 Y + 1 M with a T3/T4 ratio greater than 20. Treatment with anti-thyroid drugs (ATD) was carried out for 7 Y and there was a progressive improvement in pain complaints 8 M after starting ATD, allowing treatment with pamidronate to be discontinued. Total thyroidectomy was performed at 12 Y + 5 M. CONCLUSIONS: This is a case of MAS-associated HT that reflects the deleterious effect of thyroid hormone excess on FD, reinforcing the need of having a low threshold for suspicion of HFE that may arise.

Rare Coexistence of Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency and Turner Syndrome: A Case Report and Brief Literature Review

The coexistence of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency and Turner syndrome (TS) is rare. We report on a 6-year-old Portuguese girl with mosaic TS [45,XO(39)/47,XXX(21)] presenting with premature pubarche at the age of 5 years. Laboratory findings showed elevated 17-hydroxyprogesterone, dehydroepiandrosterone sulfate, androstenedione and total testosterone, and her sex-determining region Y (SRY) was negative. CYP21A2 gene analysis revealed two mutations (c.[844G>T]; [CYP21A2del]), consistent with the non-classical form of CAH. Complete deletion of CYP21A2 allele occurred de novo. At 6 years and 4 months, she presented with accelerated growth velocity and hydrocortisone at a dose of 5 mg/m2/day was initiated. This case highlights the need to perform global examinations looking for virilization signs in TS patients' follow-ups. It also supports the reported genetic combination of TS and CAH. Therefore, CAH should be kept in mind in TS patients with SRY negative and virilization signs, even in the absence of short stature.

Autoimmune Primary Adrenal Insufficiency in Children

Objective: Primary adrenal insufficiency (PAI) is a rare condition in children, and is potentially life-threatening. The most common cause is congenital adrenal hyperplasia, and autoimmune etiology is the most frequent acquired cause in this age group. Symptoms are usually non-specific and, when suspected, investigation should include adrenocorticotropin hormone (ACTH) and morning serum cortisol measurement and, in some cases, a cosyntropin test to confirm the diagnosis. Prompt treatment is essential to prevent an adverse outcome. Methods: We retrospectively collected clinical and laboratory data from adrenal insufficiency due to autoimmune adrenalitis, observed from 2015 to 2020 in a pediatric endocrinology department of a tertiary care hospital. Results: Eight patients were identified, seven males and one female, with age at diagnosis between 14 and 17 years. The symptoms at presentation ranged from non-specific symptoms, such as chronic fatigue and weight loss, to a severe presentation, with altered mental status and seizures. The median duration of symptoms was 4.5 months. The diagnosis was confirmed by serum cortisol and plasma ACTH measurement and all were confirmed to have autoimmune etiology (positive anti-adrenal antibodies). At diagnosis, the most common laboratory abnormality was hyponatremia. All patients were treated with hydrocortisone and fludrocortisone. One patient presented with evidence of type 2 autoimmune polyglandular syndrome. Conclusion: PAI is a rare condition in the pediatric age group. Due to non-specific symptoms, a high index of suspicion is necessary to establish a prompt diagnosis. Once an autoimmune etiology is confirmed, it is important to initiate the appropriate treatment and search for signs and symptoms of other autoimmune diseases during follow-up.

Clinical characteristics of polyglandular autoimmune syndromes in pediatric age: an observational study.

OBJECTIVES: Polyglandular autoimmune syndromes (PAS) are characterized by the association of two or more autoimmune diseases (AID) and are classified into four types. PAS type 1 is more frequently manifested in childhood, but the prevalence of other PAS in children, less described in the literature, seems to be underestimated. METHODS: This study aimed to evaluate the prevalence of PAS in a selected pediatric population of 879 children with Diabetes mellitus type 1 (DM1), autoimmune thyroid disease (AITD), and Addison's disease (AD) followed in our hospital for 10 years and describe and classify the manifestations of different PAS. RESULTS: We diagnosed 35 children with PAS, most fulfilled criteria for PAS type 3 (65.7%), and AITD was the AID more frequently detected (74.3%). PAS type 1 was not diagnosed in our sample. Patients with PAS manifested DM1 and AITD at a younger age than children with monoglandular pathology (7.7 vs. 9.3 years, p=0.04 and 7.7 vs. 13.1 years, p<0.01). CONCLUSIONS: This is the first study that analyzes the prevalence of different types of PAS in a pediatric population followed by endocrine pathologies, namely DM1, AD, and AITD. As PAS manifestations are often preceded by a long latency period characterized by the presence of autoantibodies, we reinforce the need to value these markers for timely diagnosis and to screen PAS in patients with AD throughout their lives.

A serious and unusual presentation of congenital isolated ACTH deficiency due to TBX19 mutation, beyond the neonatal period.

Summary: Congenital isolated adrenocorticotrophic hormone (ACTH) deficiency due to T-box transcription factor-19 (TBX19 mutation) (MIM 201400; ORPHA 199296) usually presents in the neonatal period with severe hypoglycemia, seizures, and sometimes prolonged cholestatic jaundice. We report a case with an unusual presentation that delayed the diagnosis. A 9-month-old female patient with no relevant personal history was admitted to the emergency department due to a hypoglycemic seizure in the context of acute gastroenteritis. There was rapid recovery after glucose administration. At age 4, she presented with tonic-clonic seizures, fever, and gastrointestinal symptoms and came to need support in an intensive care unit. Low serum cortisol was documented and hydrocortisone was initiated. After normalization of inflammatory parameters, the patient was discharged with hydrocortisone. The genetic investigation was requested and compound heterozygous mutations in TBX19 were detected. This is a rare case of presentation of TBX19 mutation outside the neonatal period and in the setting of acute disease, which presented a diagnostic challenge. Learning points: Congenital isolated adrenocorticotrophic hormone deficiency due to TBX19 mutation usually presents with neonatal hypoglycemia and prolonged cholestatic jaundice. An uneventful neonatal period, however, does not exclude the diagnosis as the disease may be asymptomatic at this stage. In the context of idiopathic hypoglycemia, even in the context of acute disease, hypocortisolism must always be excluded. Genetic evaluation should be performed in cases of congenital central hypocortisolism to allow proper counselling.

Patient-Derived Extracellular Vesicles Proteins as New Biomarkers in Multiple Myeloma - A Real-World Study.

Multiple myeloma (MM) is a hematological malignancy of clonal antibody-secreting plasma cells (PCs). MM diagnosis and risk stratification rely on bone marrow (BM) biopsy, an invasive procedure prone to sample bias. Liquid biopsies, such as extracellular vesicles (EV) in peripheral blood (PB), hold promise as new minimally invasive tools. Real-world studies analyzing patient-derived EV proteome are rare. Here, we characterized a small EV protein content from PB and BM samples in a cohort of 102 monoclonal gammopathies patients routinely followed in the clinic and 223 PB and 111 BM samples were included. We investigated whether EV protein and particle concentration could predict an MM patient prognosis. We found that a high EV protein/particle ratio, or EV cargo >0.6 µg/108 particles, is related to poorer survival and immune dysfunction. These results were supported at the protein level by mass spectrometry. We report a set of PB EV-proteins (PDIA3, C4BPA, BTN1A1, and TNFSF13) with a new biomarker potential for myeloma patient outcomes. The high proteomic similarity between PB and BM matched pairs supports the use of circulating EV as a counterpart of the BM EV proteome. Overall, we found that the EV protein content is related to patient outcomes, such as survival, immune dysfunction, and possibly treatment response.

Effect of ultra-rapid insulin aspart on glycemic control in children with type 1 diabetes: the experience of a Portuguese tertiary centre.

Background: Postprandial hyperglycemia is one of the biggest challenges in children with type 1 diabetes (T1D). Ultra-fast-acting aspartic insulin (faster aspart) has a quicker onset of action and an earlier maximum activity. The aim of this study is to analyze the impact of faster aspart in metabolic control of pediatric patients with T1D in a "real-world" setting. Methods: Retrospective analysis of 60 pediatric patients with T1D who changed their insulin analogue to faster aspart. Anthropometric data, insulin doses, capillary and interstitial glucose recordings and average glycated hemoglobin before and after insulin analogue's switch were obtained. After all population analyses, patients were analyzed separately according to the type of treatment, multiple daily injections (MDI) and continuous subcutaneous insulin infusion (CSII), and according to age group. Results: Faster aspart significantly improved metabolic control, increasing time in range (TIR) (42 vs.54%, respectively; P = 0.007) and decreasing time above range (TAR) (52 vs.40%, respectively; P = 0.009), without an increased time in hypoglycemia (7% before and after faster aspart's introduction; P = 0.933). This was reassured in the adolescent years (n = 45), with an increase in TIR (37 vs. 47%, respectively; P = 0.034) and decrease in TAR (51 vs. 45%, respectively; P = 0.022). Patients on CSII (n = 47), also demonstrated an increase in TIR (38 vs. 50%, respectively; P = 0.010). The reduction of A1c was not statistically significant. Conclusion: Although the advantage of faster aspart had already been demonstrated in pediatric patients under MDI, "real-world" studies, including patients under CSII, are still lacking. This study highlights the important impact of faster aspart on metabolic control in children with T1D, particularly among adolescents under CSII.

Multiple Myeloma-Derived Extracellular Vesicles Modulate the Bone Marrow Immune Microenvironment.

Multiple myeloma (MM), the third most frequent hematological cancer worldwide, is characterized by the proliferation of neoplastic plasma cells in the bone marrow (BM). One of the hallmarks of MM is a permissive BM microenvironment. Increasing evidence suggests that cell-to-cell communication between myeloma and immune cells via tumor cell-derived extracellular vesicles (EV) plays a key role in the pathogenesis of MM. Hence, we aimed to explore BM immune alterations induced by MM-derived EV. For this, we inoculated immunocompetent BALB/cByJ mice with a myeloma cell line, MOPC315.BM, inducing a MM phenotype. Upon tumor establishment, characterization of the BM microenvironment revealed the expression of both activation and suppressive markers by lymphocytes, such as granzyme B and PD-1, respectively. In addition, conditioning of the animals with MOPC315.BM-derived EV, before transplantation of the MOPC315.BM tumor cells, did not anticipate the disease phenotype. However, it induced features of suppression in the BM milieu, such as an increase in PD-1 expression by CD4+ T cells. Overall, our findings reveal the involvement of MOPC315.BM-derived EV protein content as promoters of immune niche remodeling, strengthening the importance of assessing the mechanisms by which MM may impact the immune microenvironment.

Impact of Pre-Analytical and Analytical Variables Associated with Sample Preparation on Flow Cytometric Stainings Obtained with EuroFlow Panels.

Objective interpretation of FC results may still be hampered by limited technical standardization. The EuroFlow consortium conducted a series of experiments to determine the impact of different variables on the relative distribution and the median fluorescence intensity (MFI) of markers stained on different cell populations, from both healthy donors and patients' samples with distinct hematological malignancies. The use of different anticoagulants; the time interval between sample collection, preparation, and acquisition; pH of washing buffers; and the use of cell surface membrane-only (SM) vs. cell surface plus intracytoplasmic (SM+CY) staining protocols, were evaluated. Our results showed that only monocytes were represented at higher percentages in EDTA- vs. heparin-anticoagulated samples. Application of SM or SM+CY protocols resulted in slight differences in the percentage of neutrophils and debris determined only with particular antibody combinations. In turn, storage of samples for 24 h at RT was associated with greater percentage of debris and cell doublets when the plasma cell disorder panel was used. Furthermore, 24 h storage of stained cells at RT was selectively detrimental for MFI levels of CD19 and CD45 on mature B- and T-cells (but not on leukemic blasts, clonal B- and plasma cells, neutrophils, and NK cells). The obtained results showed that the variables evaluated might need to be tailored for sample and cell type(s) as well as to the specific markers compared; however, defining of well-balanced boundaries for storage time, staining-to-acquisition delay, and pH of washing buffer would be a valid recommendation for most applications and circumstances described herein.

Expert-independent classification of mature B-cell neoplasms using standardized flow cytometry: a multicentric study.

Reproducible expert-independent flow-cytometric criteria for the differential diagnoses between mature B-cell neoplasms are lacking. We developed an algorithm-driven classification for these lymphomas by flow cytometry and compared it to the WHO gold standard diagnosis. Overall, 662 samples from 662 patients representing 9 disease categories were analyzed at 9 laboratories using the previously published EuroFlow 5-tube-8-color B-cell chronic lymphoproliferative disease antibody panel. Expression levels of all 26 markers from the panel were plotted by B-cell entity to construct a univariate, fully standardized diagnostic reference library. For multivariate data analysis, we subsequently used canonical correlation analysis of 176 training cases to project the multidimensional space of all 26 immunophenotypic parameters into 36 2-dimensional plots for each possible pairwise differential diagnosis. Diagnostic boundaries were fitted according to the distribution of the immunophenotypes of a given differential diagnosis. A diagnostic algorithm based on these projections was developed and subsequently validated using 486 independent cases. Negative predictive values exceeding 92.1% were observed for all disease categories except for follicular lymphoma. Particularly high positive predictive values were returned in chronic lymphocytic leukemia (99.1%), hairy cell leukemia (97.2%), follicular lymphoma (97.2%), and mantle cell lymphoma (95.4%). Burkitt and CD10+ diffuse large B-cell lymphomas were difficult to distinguish by the algorithm. A similar ambiguity was observed between marginal zone, lymphoplasmacytic, and CD10- diffuse large B-cell lymphomas. The specificity of the approach exceeded 98% for all entities. The univariate immunophenotypic library and the multivariate expert-independent diagnostic algorithm might contribute to increased reproducibility of future diagnostics in mature B-cell neoplasms.