Neonatal Reference Intervals for the Complete Blood Count Parameters MicroR and HYPO-He: Sensitivity Beyond the Red Cell Indices for Identifying Microcytic and Hypochromic Disorders.

OBJECTIVE: To create neonatal reference intervals for the MicroR and HYPO-He complete blood count (CBC) parameters and to test whether these parameters are sensitive early markers of disease at early stages of microcytic/hypochromic disorders while the CBC indices are still normal. STUDY DESIGN: We retrospectively collected the CBC parameters MicroR and HYPO-He, along with the standard CBC parameters, from infants aged 0-90 days at Intermountain Healthcare hospitals using Sysmex hematology analyzers. We created reference intervals for these parameters by excluding values from neonates with proven microcytic disorders (ie, iron deficiency or alpha thalassemia) from the dataset. RESULT: From >11 000 CBCs analyzed, we created reference intervals for MicroR and HYPO-He in neonates aged 0-90 days. The upper intervals are considerably higher in neonates than in adults, validating increased anisocytosis and polychromasia among neonates. Overall, 52% of neonates with iron deficiency (defined by reticulocyte hemoglobin equivalent <25 pg) had a MicroR >90% upper interval (relative risk, 4.14; 95% CI, 3.80-4.53; P < .001), and 68% had an HYPO-He >90% upper interval (relative risk, 6.64; 95% CI, 6.03-7.32; P < .001). These 2 new parameters were more sensitive than the red blood cell (RBC) indices (P < .001) in identifying 24 neonates with iron deficiency at birth. CONCLUSIONS: We created neonatal reference intervals for MicroR and HYPO-He. Although Sysmex currently designates these as research use only in the US, they can be measured as part of a neonate's CBC with no additional phlebotomy volume or run time and can identify microcytic and hypochromic disorders even when the RBC indices are normal.

Association of the dispersion in red blood cell volume with mortality.

BACKGROUND: The red cell distribution width (RDW) predicts mortality among many populations. RDW is calculated as the standard deviation (SD) of the red blood cell (RBC) volume divided by mean corpuscular volume (MCV). Because higher MCV also predicts mortality, we hypothesized that the RDW numerator (one SD of RBC volume or 1SD-RDW) predicts mortality more strongly than the RDW. MATERIAL AND METHODS: Adult subjects hospitalized during a contemporary clinical era (10/2005-1/2014, N = 135,963) and a historical era (1/1999-9/2005, N = 119,530) were studied. The RDW was obtained from the complete blood count (CBC), while 1SD-RDW was calculated (RDW multiplied by MCV and divided by 100). RESULTS: In univariable Cox regression (2005-2014 cohort), 1SD-RDW (quintile 5 vs. 1: hazard ratio [HR] = 8.38, 95% confidence interval [CI] = 7.94, 8.85; P < 0.001) was a superior predictor of mortality compared to RDW (quintile 5 vs. 1: HR = 4.78, CI = 4.57, 5.00; P < 0.001). This superiority remained after adjustment for age, sex, basic metabolic profile components and other CBC factors excluding MCV (1SD-RDW: HR = 2.41, CI = 2.28, 2.55; RDW: HR = 2.01, CI = 1.92, 2.11). Further adjustment for MCV strengthened the RDW association (HR = 2.14, CI = 2.04, 2.24; P < 0.001), becoming indistinct from 1SD-RDW (HR = 2.20, CI = 2.08, 2.33; P < 0.001). Findings were similar for the 1999-2005 cohort. CONCLUSIONS: The 1SD-RDW predicted mortality more strongly than RDW, suggesting that 1SD-RDW is superior to RDW as an individual risk predictor. Further, these results indicate that the dispersion of RBC volume and its mean are independent risk markers. Further research is required to understand the clinical value and mechanistic basis of these associations.

Reference intervals for common coagulation tests of preterm infants (CME).

BACKGROUND: Fresh-frozen plasma (FFP) is sometimes administered to nonbleeding preterm neonates who are judged to be at risk for bleeding because they have abnormal coagulation tests. The benefits/risks of this practice are not well defined. One limitation to progress is lack of reference intervals for the common coagulation tests, thus limiting precision about whether coagulation tests are indeed abnormal. STUDY DESIGN AND METHODS: In a sequential observational study, fetal blood was drawn at preterm birth (≤ 34 weeks) from the umbilical vein near the placenta. Fibrinogen, prothrombin time, activated partial thromboplastin time, D-dimer, platelet (PLT) count, and mean PLT volume were measured. Reference intervals were constructed using 5th and 95th percentile values. Associations were then sought between abnormal coagulation values at birth and bleeding problems identified during the first week. RESULTS: Coagulation tests were drawn at 175 preterm deliveries and the results were organized into reference intervals by gestational age. No abnormal coagulation value, either alone or in combination, predicted hemorrhage (intraventricular, gastrointestinal, or pulmonary) during the first week. However, fibrinogen exceeding the 95th percentile was associated with evidence of in utero infection/inflammation (correlations with elevated C-reactive protein, p<0.01, and elevated immature to total neutrophil ratio, p<0.001). CONCLUSIONS: Abnormal coagulation values at preterm birth do not predict bleeding during the first week. This suggests to us that bleeding in the days after preterm birth is not generally the result of in utero coagulopathy. These findings bring into question the value of coagulation screening of nonbleeding preterm infants and prophylactic FFP administration to those with abnormal values.

Using patients like my patient for clinical decision support: institution-specific probability of celiac disease diagnosis using simplified near-neighbor classification.

BACKGROUND: Interpretation of a diagnostic test result requires knowing what proportion of patients with a "similar" result has the condition in question. This information is often not readily available from the medical literature, or may be based on different clinical populations that make it nonapplicable. In certain settings, where correlated screening parameters and diagnostic data are available in electronic medical records, a representation of diagnostic test performance on "patients like my patient" can be obtained. OBJECTIVE: We sought to integrate patient demographic and physician practice information using a simplified nearest neighbor algorithm. We used this method to illustrate the relationship between tTG IgA test result and duodenal biopsy for celiac disease in a local diagnostic context. PARTICIPANTS: We used a data set of 1,461 paired tissue transglutaminase (tTG) IgA and definitive duodenal biopsy results from Intermountain Healthcare with data on patient age and ordering physician specialty. This was split into a discovery set of 1,000 and a validation set of 461 paired results. MAIN MEASURES: Accuracy of the local discovery data set in predicting probability of positive duodenal biopsy and confidence intervals around predicted probability in the test data compared to probabilities of positive biopsy implied from published logistic regression and from published sensitivity and specificity studies. KEY RESULTS: The near-neighbor method could estimate probability of clinical outcomes with predictive performance equivalent to other methods while adjusting probability estimates and confidence intervals to fit specific clinical situations. CONCLUSIONS: Data from clinical encounters obtained from electronic medical records can yield prediction estimates that are tailored to the individual patient, local population, and healthcare delivery processes. Local analysis of diagnostic probability may be more clinically meaningful than probabilities inferred from published studies. This local utility may come at the expense of external validity and generalizability.

Intermittent fasting and changes in clinical risk scores: Secondary analysis of a randomized controlled trial.

Background: Intermittent fasting may increase longevity and lower cardiometabolic risk. This study evaluated whether fasting modifies clinical risk scores for mortality [i.e., Intermountain Mortality Risk Score (IMRS)] or chronic diseases [e.g., Pooled Cohort Risk Equations (PCRE), Intermountain Chronic Disease score (ICHRON)]. Methods and results: Subjects (N = 71) completing the WONDERFUL trial were aged 21-70 years, had ≥1 metabolic syndrome criteria, elevated cholesterol, and no anti-diabetes medications, statins, or chronic diseases. The intermittent fasting arm underwent 24-h water-only fasting twice-per-week for 4 weeks and once-per-week for 22 weeks (26 weeks total). Analyses examined the IMRS change score at 26 weeks vs. baseline between intermittent fasting (n = 38) and ad libitum controls (n = 33), and change scores for PCRE, ICHRON, HOMA-IR, and a metabolic syndrome score (MSS). Age averaged 49 years; 65% were female. Intermittent fasting increased IMRS (0.78 ± 2.14 vs. controls: -0.61 ± 2.56; p = 0.010) but interacted with baseline IMRS (p-interaction = 0.010) to reduce HOMA-IR (but not MSS) more in subjects with higher baseline IMRS (median HOMA-IR change: fasters, -0.95; controls, +0.05) vs. lower baseline IMRS (-0.29 vs. -0.32, respectively). Intermittent fasting reduced ICHRON (-0.92 ± 2.96 vs. 0.58 ± 3.07; p = 0.035) and tended to reduce PCRE (-0.20 ± 0.22 vs. -0.14 ± 0.21; p = 0.054). Conclusions: Intermittent fasting increased 1-year IMRS mortality risk, but decreased 10-year chronic disease risk (PCRE and ICHRON). It also reduced HOMA-IR more in subjects with higher baseline IMRS. Increased IMRS suggests fasting may elevate short-term mortality risk as a central trigger for myriad physiological responses that elicit long-term health improvements. Increased IMRS may also reveal short-term fasting-induced safety concerns.

Association of the Intermountain Risk Score with major adverse health events in patients positive for COVID-19: an observational evaluation of a US cohort.

OBJECTIVES: The Intermountain Risk Score (IMRS), composed using published sex-specific weightings of parameters in the complete blood count (CBC) and basic metabolic profile (BMP), is a validated predictor of mortality. We hypothesised that IMRS calculated from prepandemic CBC and BMP predicts COVID-19 outcomes and that IMRS using laboratory results tested at COVID-19 diagnosis is also predictive. DESIGN: Prospective observational cohort study. SETTING: Primary, secondary, urgent and emergent care, and drive-through testing locations across Utah and in sections of adjacent US states. Viral RNA testing for SARS-CoV-2 was conducted from 3 March to 2 November 2020. PARTICIPANTS: Patients aged ≥18 years were evaluated if they had CBC and BMP measured in 2019 and tested positive for COVID-19 in 2020. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was a composite of hospitalisation or mortality, with secondary outcomes being hospitalisation and mortality separately. RESULTS: Among 3883 patients, 8.2% were hospitalised and 1.6% died. Subjects with low, mild, moderate and high-risk IMRS had the composite endpoint in 3.5% (52/1502), 8.6% (108/1256), 15.5% (152/979) and 28.1% (41/146) of patients, respectively. Compared with low-risk, subjects in mild-risk, moderate-risk and high-risk groups had HR=2.33 (95% CI 1.67 to 3.24), HR=4.01 (95% CI 2.93 to 5.50) and HR=8.34 (95% CI 5.54 to 12.57), respectively. Subjects aged <60 years had HR=3.06 (95% CI 2.01 to 4.65) and HR=7.38 (95% CI 3.14 to 17.34) for moderate and high risks versus low risk, respectively; those ≥60 years had HR=1.95 (95% CI 0.99 to 3.86) and HR=3.40 (95% CI 1.63 to 7.07). In multivariable analyses, IMRS was independently predictive and was shown to capture substantial risk variation of comorbidities. CONCLUSIONS: IMRS, a simple risk score using very basic laboratory results, predicted COVID-19 hospitalisation and mortality. This included important abilities to identify risk in younger adults with few diagnosed comorbidities and to predict risk prior to SARS-CoV-2 infection.

Postponing or eliminating red blood cell transfusions of very low birth weight neonates by obtaining all baseline laboratory blood tests from otherwise discarded fetal blood in the placenta.

BACKGROUND: Safely reducing the proportion of very low birth weight neonates (<1500 g) that receive a red blood cell (RBC) transfusion would be an advance in transfusion practice. STUDY DESIGN AND METHODS: We performed a prospective, single-centered, case-control, feasibility analysis, preparatory to designing a definitive trial. Specifically, we sought to determine whether we could obtain all baseline neonatal intensive care unit blood tests from the placenta, after placental delivery, thereby initially drawing no blood from the neonate. RESULTS: Ten cases where all baseline blood tests were drawn from the placenta, and 10 controls where all tests were drawn from the neonate, were closely matched for birth weight, gestational age, sex, and race. Early cord clamping was used for all 20. Over the first 18 hours the hemoglobin increased in nine cases versus two controls (p = 0.005). During the first 72 hours one case versus five controls qualified for and received an RBC transfusion. In the first week the cases received four transfusions and the controls received 16 (p = 0.02). None of the cases had an intraventricular hemorrhage (IVH) but four of the controls had a Grade 1 and two had a Grade 3 (p = 0.01). CONCLUSION: We speculate that this method is feasible and generally postpones the first RBC transfusion until beyond the period of peak vulnerability to IVH.

Reconciling markedly discordant values of serum ferritin versus reticulocyte hemoglobin content.

OBJECTIVE: To determine why serum ferritin and reticulocyte hemoglobin (RET-He), drawn to assess neonatal iron sufficiency, sometimes have markedly discordant results. STUDY DESIGN: Retrospective records review of five NICUs over 28 months, identifying all patients with a ferritin and RET-He within 48 h. We examined records of all who had marked discordance (one value >95th % reference interval, the other <5th %). RESULTS: Of 190 paired ferritin and RET-He measurements, 16 (8%) were markedly discordant. Fifteen of the 16 discordant samples involved a high ferritin and a low RET-He. In these, low MCV and high %Micro-R, and low MCH and high %HYPO-He were present. In total, 8 of the 15 had laboratory or clinical evidence of an inflammatory process and five had suspicion of infection documented. CONCLUSIONS: When ferritin and RET-He were discordant, erythrocyte microcytosis and hypochromasia suggested that the RET-He gave the more accurate interpretation; that iron deficiency was likely present.

Preferential Metabolic Improvement by Intermittent Fasting in People with Elevated Baseline Red Cell Distribution Width: A Secondary Analysis of the WONDERFUL Randomized Controlled Trial.

Red cell distribution width (RDW) predicts cardiovascular outcomes, but it is unstudied with regard to intermittent fasting. In WONDERFUL trial subjects, the effect of the interaction between baseline RDW and intermittent fasting on changes in insulin and other cardiometabolic endpoints and the effect of fasting on changes in RDW were evaluated. The subjects enrolled were aged 21-70 years and were free of statins, anti-diabetes medications, and chronic diseases, and had ≥1 metabolic syndrome feature, as well as elevated low-density lipoprotein cholesterol. Subjects were randomized to 24-h, water-only fasting (twice per week for 4 weeks, once per week for 22 weeks) or 26 weeks of ad libitum eating. Subjects (N = 71; n = 38 intermittent fasting, n = 33 controls) had more substantial changes in insulin in intermittent fasting vs. controls (-3.45 ± 2.27 vs. 0.48 ± 3.55 mIU/L) when baseline RDW size distribution (RDW-SD) was ≥median (42.6 fL) than

Automated Quantification of Fragmented Red Blood Cells: Neonatal Reference Intervals and Clinical Disorders of Neonatal Intensive Care Unit Patients with High Values.

BACKGROUND: Schistocytes are circulating erythrocyte fragments. They can be identified microscopically from a blood smear; but automated systems evaluate more cells and avoid inconsistencies in microscopy. Studies using adult subjects indicate that automated quantification of schistocytes can be clinically useful. However, reference intervals for automated schistocyte counts of neonates have not been published, and the relevance of a high automated schistocyte count from neonates has not been reported. OBJECTIVES: Using retrospective automated neonatal complete blood count (CBC) data, we created reference intervals for fragmented red cells (FRCs) and sought to discover the clinical conditions of neonates with high FRCs (above the upper reference interval). RESULTS: We created reference intervals based on 39,949 CBCs from 15,655 neonates 0-90 days old. The lower reference interval was 0 FRC/µL and the upper interval was 100,000/µL. The highest FRCs (96 CBCs from 44 neonates) were > 250,000/µL. These neonates clustered into the following groups: 37% had sepsis, 29% had disseminated intravascular coagulation (DIC), 17% had a genetic syndrome, 14% necrotizing enterocolitis (NEC), and 7% had iron deficiency (some had more than one diagnosis). Based on the reference intervals, we divided the 39,949 FRC values into 3 groups: (1) < 100,000/µL ("normal"), (2) 100,000-200,000/µL ("moderately elevated"), and (3) > 200,000/µL ("extremely elevated"). The odds that a microangiopathic condition (DIC, sepsis, NEC) or a microcytic disorder (iron deficiency) were present were significantly higher in the moderately elevated, and more so in the extremely elevated group. CONCLUSIONS: Our study suggests that a high FRC could prompt investigation into, or inform follow-up of, a neonatal microangiopathic or extremely microcytic disorder.

Neonates with suspected microangiopathic disorders: performance of standard manual schistocyte enumeration vs. the automated fragmented red cell count.

OBJECTIVES: To enhance the diagnosis of schistocyte-producing conditions, we compared routine manual schistocyte enumeration with automated fragmented red cell counts (FRCs). STUDY DESIGN: In neonates "suspected" of having sepsis, NEC, or DIC we compared manual schistocyte estimates vs. automated FRC counts. When the two disagreed, we used a "gold standard" from a  ≥ 1000 RBC differential. We also assessed the diagnostic accuracy of the FRC count in diagnosing sepsis, NEC, or DIC. RESULTS: We collected 270 CBCs from 90 neonates. The methods agreed in 63% (95% CI 55%-70%) of the CBCs. Among the 37% where they disagreed, the FRC count was more accurate in 100% (95% CI 88-100%). An elevated FRC count was specific for sepsis, and was sensitive and specific for necrotizing enterocolitis and DIC. CONCLUSIONS: Automated FRC counts have advantages over routine manual evaluation, larger sample size, lower expense, and superior accuracy in diagnosing schistocyte-producing conditions.

Extreme erythrocyte macrocytic and microcytic percentages are highly predictive of morbidity and mortality.

BACKGROUND: The red cell distribution width (RDW) is associated with health outcomes. Whether non-RDW risk information is contained in RBC sizes is unknown. This study evaluated the association of the percentage of extreme macrocytic RBCs (%Macro, RBC volume > 120 fl) and microcytic RBCs (%Micro, RBC volume < 60 fl) and the RDW-size distribution (RDW-sd) with mortality and morbidity. METHODS: Patients (females, n = 165,770; males, n = 100,210) at Intermountain Healthcare were studied if they had a hematology panel between May 2014 and September 2016. Adjusted sex-specific associations of %Macro/%Micro and RDW-sd with mortality and 33 morbidities were evaluated. RESULTS: Among females with fourth-quartile values of %Macro quartile and %Micro (referred to throughout as 4/4), there was an average of 7.2 morbidities versus 2.9 in the lowest risk (LR1) categories, 1/1, 1/2, 2/1, and 2/2 (P < 0.001). Among males, those in the 4/4 category had 8.0 morbidities, while those in the LR1 had 3.4 (P < 0.001). Cox regressions found %Macro/%Micro (4/4 vs. LR1, females: hazard ratio [HR] = 1.97 [95% CI = 1.53, 2.54]; males: HR = 2.17 [CI = 1.72, 2.73]), RDW-sd (quartile 4 vs. 1, females: HR = 1.33 [CI = 1.04, 1.69]; males: HR = 1.41 [CI = 1.10, 1.80]), and RDW (quartile 4 vs. 1, females: HR = 1.59 [CI = 1.26, 2.00]; males: HR = 1.23 [CI = 0.99, 1.52]) independently predicted mortality. Limitations include that the observational design did not reveal causality and unknown confounders may be unmeasured. CONCLUSIONS: Concomitantly elevated %Macro and %Micro predicted the highest mortality risk and the greatest number of morbidities, revealing predictive ability of RBC volume beyond what is measured clinically. Mechanistic investigations are needed to explain the biological basis of these observations. FUNDING: This study was supported by internal Intermountain Heart Institute funds and in-kind support from Sysmex America Inc.

A case for manual entry of structured, coded laboratory data from multiple sources into an ambulatory electronic health record.

Laboratory results provide necessary information for the management of ambulatory patients. To realize the benefits of an electronic health record (EHR) and coded laboratory data (e.g., decision support and improved data access and display), results from laboratories that are external to the health care enterprise need to be integrated with internal results. We describe the development and clinical impact of integrating external results into the EHR at Intermountain Health Care (IHC). During 2004, over 14,000 external laboratory results for 128 liver transplant patients were added to the EHR. The results were used to generate computerized alerts that assisted clinicians with managing laboratory tests in the ambulatory setting. The external results were sent from 85 different facilities and can now be viewed in the EHR integrated with IHC results. We encountered regulatory, logistic, economic, and data quality issues that should be of interest to others developing similar applications.

Red blood cell distribution width: reference intervals for neonates.

OBJECTIVE: To create reference intervals for red blood cell distribution width (RDW) of neonates and to use these intervals to better understand and classify hematopathology of neonates. STUDY DESIGN: This was a retrospective analysis of data from neonates born between 1/1/2001 and 12/31/2011, who had a complete blood cell count (CBC) in the first 14 days. The first RDW recorded from each was displayed according to gestational and postnatal age. Correlation between RDW and reticulocyte count was sought when the two tests were obtained simultaneously. Focused studies were performed on the 20 neonates with the highest and the 10 with the lowest RDW values. RESULTS: RDW values from 165,613 CBCs were included. RDW reference intervals for neonates are higher than for older children and adults. At birth, the lower reference limit for term and late preterm neonates is 15.5%. The upper reference limit is 20%, and is slightly higher (up to 23%) in preterm neonates. For term and late preterm neonates the range does not change in the first two weeks but preterm neonates have a rise in upper reference limit concordant with erythrocyte transfusions. RDW and reticulocytes correlated positively but weakly (r(2 )= 0.187). Eighteen of the 20 with the highest RDW values (29.4-42.8%) at birth had anemia with prenatal hemorrhage or hemolysis. Those with the lowest RDW values (11.8-13.7%) at birth tended to have a low MCV for age (95.5 ± 11.4 fL versus.129.8 ± 19.3 fL with a high RDW, p < 0.00001). CONCLUSION: The RDW reference interval at birth is 15.5-20% and does not change appreciably over the first two weeks except for those receiving a transfusion where the RDW increases. High RDW values at birth indicate anisocytosis commonly due to macrocytic reticulocytosis; low values correlate with relative microcytosis.