The seasonal distribution of immune thrombotic thrombocytopenic purpura is influenced by geography: Epidemiologic findings from a multi-center analysis of 719 disease episodes.

Prior studies have suggested that immune thrombotic thrombocytopenic purpura (iTTP) may display seasonal variation; however, methodologic limitations and sample sizes have diminished the ability to perform a rigorous assessment. This 5-year retrospective study assessed the epidemiology of iTTP and determined whether it displays a seasonal pattern. Patients with both initial and relapsed iTTP (defined as a disintegrin and metalloprotease with thrombospondin type motifs 13 activity <10%) from 24 tertiary centers in Australia, Canada, France, Greece, Italy, Spain, and the US were included. Seasons were defined as: Northern Hemisphere-winter (December-February); spring (March-May); summer (June-August); autumn (September-November) and Southern Hemisphere-winter (June-August); spring (September-November); summer (December-February); autumn (March-May). Additional outcomes included the mean temperature in months with and without an iTTP episode at each site. A total of 583 patients experienced 719 iTTP episodes. The observed proportion of iTTP episodes during the winter was significantly greater than expected if equally distributed across seasons (28.5%, 205/719, 25.3%-31.9%; p = .03). Distance from the equator and mean temperature deviation both positively correlated with the proportion of iTTP episodes during winter. Acute iTTP episodes were associated with the winter season and colder temperatures, with a second peak during summer. Occurrence during winter was most pronounced at sites further from the equator and/or with greater annual temperature deviations. Understanding the etiologies underlying seasonal patterns of disease may assist in discovery and development of future preventative therapies and inform models for resource utilization.

A Propensity-Matched Cohort Study of Intravenous Iron versus Red Cell Transfusions for Preoperative Iron-Deficiency Anemia.

BACKGROUND: While preoperative anemia is associated with adverse perioperative outcomes, the benefits of treatment with iron replacement versus red blood cell (RBC) transfusion remain uncertain. We used a national database to establish trends in preoperative iron-deficiency anemia (IDA) treatment and to test the hypothesis that treatment with preoperative iron may be superior to RBC transfusion. METHODS: This study is a propensity-matched retrospective cohort analysis from 2003 to 2023 using TriNetX Research Network, which included surgical patients diagnosed with IDA within 3 months preoperatively. After matching for surgery type and comorbidities, we compared a cohort of patients with preoperative IDA who were treated with preoperative intravenous (IV) iron but not RBCs (n = 77,179), with a cohort receiving preoperative RBCs but not IV iron (n = 77,179). Propensity-score matching was performed for age, ethnicity, race, sex, overweight and obesity, type 2 diabetes, hyperlipidemia, essential hypertension, heart failure, chronic ischemic heart disease, neoplasms, hypothyroidism, chronic kidney disease, nicotine dependence, surgery type, and lab values from the day of surgery including ferritin, transferrin, and hemoglobin split into low (<7 g/dL), medium (7-<12 g/dL), and high (≥12 g/dL) to account for anemia severity. The primary outcome was 30-day postoperative mortality with the secondary outcomes being 30-day morbidity, postoperative hemoglobin level, and 30-day postoperative RBC transfusion. RESULTS: Compared with RBC transfusion, preoperative IV iron was associated with lower risk of postoperative mortality (n = 2550/77,179 [3.3%] vs n = 4042/77,179 [5.2%]; relative risk [RR], 0.63, 95% confidence interval [CI], 0.60-0.66), and a lower risk of postoperative composite morbidity (n = 14,174/77,179 [18.4%] vs n = 18,632/77,179 [24.1%]; RR, 0.76, 95% CI, 0.75-0.78) (both P = .001 after Bonferroni adjustment). Compared with RBC transfusion, IV iron was also associated with a higher hemoglobin in the 30-day postoperative period (10.1 ± 1.8 g/dL vs 9.4 ± 1.7 g/dL, P = .001 after Bonferroni adjustment) and a reduced incidence of postoperative RBC transfusion (n = 3773/77,179 [4.9%] vs n = 12,629/77,179 [16.4%]; RR, 0.30, 95% CI, 0.29-0.31). CONCLUSIONS: In a risk-adjusted analysis, preoperative IDA treatment with IV iron compared to RBC transfusion was associated with a reduction in 30-day postoperative mortality and morbidity, a higher 30-day postoperative hemoglobin level, and reduced postoperative RBC transfusion. This evidence represents a promising opportunity to improve patient outcomes and reduce blood transfusions and their associated risk and costs.

Chronic automated red cell exchange therapy for sickle cell disease.

BACKGROUND: The data to support chronic automated red cell exchange (RCE) in sickle cell disease (SCD) outside of stroke prevention, is limited, especially in adults. STUDY DESIGN AND METHODS: A retrospective analysis was conducted of patients with SCD who were referred for chronic RCE at our institution over a 10-year period. Data that were evaluated included patient demographics, referral indications, and procedural details (e.g., vascular access, adverse events, etc.). In a subanalysis, the number of annual acute care encounters during 3 years of chronic RCE was compared with that in the year preceding the first RCE. RESULTS: A total of 164 patients were referred for chronic RCE: median age was 28 years (interquartile range [IQR] = 22-36) at referral and 60% were female. Seventy (42.6%) were naïve to chronic transfusion (simple or RCE) prior to referral. The leading indications for referral were refractory pain (73/164, 44.5%) and iron overload (57/164, 34.7%). A total of 5090 procedures occurred during the study period (median = 19, IQR = 5-45). Of the 138 patients who had central vascular access, 8 (6%) and 16 (12%) had ≥1 central-line-related thrombosis and/or infection, respectively. Of those who were not RBC alloimmunized at initiation of RCE, 12/105 (11.4%) developed new antibodies during chronic RCE. In those 30 patients who were adherent to therapy for 3 years, there was no significant difference in acute care encounters following initiation of RCE. CONCLUSION: Prospective clinical trials are needed to determine which patients are most likely to benefit from chronic RCE and refine selection accordingly.

Suspected autoimmune encephalitis: A retrospective study of patients referred for therapeutic plasma exchange.

INTRODUCTION: Autoimmune encephalitis (AE) comprises a heterogeneous group of autoantibody-mediated disorders targeting the brain parenchyma. Therapeutic plasma exchange (TPE), one of several first-line therapies for AE, is often initiated when AE is suspected, albeit prior to an established diagnosis. We sought to characterize the role of TPE in the treatment of suspected AE. METHODS: A single-center, retrospective analysis was performed of adults (≥18 years) who underwent at least one TPE procedure for "suspected AE." The following parameters were extracted and evaluated descriptively: clinicopathologic characteristics, treatment course, TPE-related adverse events, outcomes (e.g., modified Rankin scale [mRS]), and diagnosis once investigation was complete. RESULTS: A total of 37 patients (median age 56 years, range 28-77 years, 62.2% male) were evaluated. Autoimmune antibody testing was positive in serum for 43.2% (n = 16) and cerebrospinal fluid for 29.7% (n = 11). Patients underwent a median of five TPE procedures (range 3-16), with 97.3% (n = 36) via a central line and 21.6% (n = 8) requiring at least one unit of plasma as replacement fluid. Fifteen patients (40.5%) experienced at least one TPE-related adverse event. Compared with mRS at admission, the mRS at discharge was improved in 21.6% (n = 8), unchanged in 59.5% (n = 22), or worse in 18.9% (n = 7). Final diagnosis of AE was determined to be definite in 48.6% (n = 18), probable in 8.1% (n = 3) and possible in 27.0% (n = 10). Six (16.2%) patients were ultimately determined to have an alternate etiology. CONCLUSION: Empiric TPE for suspected AE is generally well-tolerated. However, its efficacy remains uncertain in the absence of controlled trials, particularly in the setting of seronegative disease.

Euvolemic automated transfusion to treat severe anemia in sickle cell disease patients at risk of circulatory overload.

BACKGROUND: Red blood cell (RBC) transfusion remains a major treatment for sickle cell disease (SCD). Patients with SCD have a high prevalence of renal impairment and cardiorespiratory disease, conferring risk of transfusion-associated circulatory overload (TACO). STUDY DESIGN AND METHODS: We describe an approach, titled euvolemic automated transfusion (EAT), to transfuse SCD patients with severe anemia who are at risk of TACO. In EAT, plasmapheresis is performed using donor RBCs, rather than albumin or plasma, as replacement fluid. Euvolemia is maintained. A retrospective analysis was conducted of patients with SCD who underwent EAT at our institution over a 10-year period, to evaluate the efficacy and safety of EAT. RESULTS: Eleven SCD patients underwent 109 EAT procedures (1-59 procedures per patient). The median age was 42 years (IQR = [30-49]) and 82% (n = 9) were female. Most (82%; n = 9) patients had severe chronic kidney disease and 55% (n = 6) had heart failure. One (9%) patient had a history of life-threatening TACO. Mean pre- and post-procedure Hct values were 19.8% (SD ± 1.6%) and 29.1% (SD ± 1.4%), respectively. The average Hct increment was 3.2% per RBC unit. Only two EAT-related complications were recorded during the 109 procedures: central line-associated infection and citrate toxicity (muscle cramping). EAT used an average of two RBC units less than that projected for standard automated RBC exchange. CONCLUSION: Our findings suggest that EAT is safe and effective to treat patients with SCD and severe anemia, who are at risk for TACO. EAT requires fewer RBC units compared to automated RBC exchange.

Reevaluation of the medical necessity of washed red blood cell transfusion in chronically transfused adults.

BACKGROUND: Washing red blood cell (RBC) units mitigates severe allergic transfusion reactions. However, washing reduces the time to expiration and the effective dose. Automated washing is time- and labor-intensive. A shortage of cell processor tubing sets prompted review of medical necessity for washed RBC for patients previously thought to require washing. STUDY DESIGN AND METHODS: A single-center, retrospective study investigated discontinuing wash RBC protocols in chronically transfused adults. In select patients with prior requirements for washing, due to a history of allergic transfusion reactions, trials of unwashed transfusions were performed. Patient demographic, clinical, laboratory, and transfusion data were compiled. The per-unit washing cost was the sum of the tubing set, saline, and technical labor costs. RESULTS: Fifteen patients (median age 34 years interquartile range [IQR] 23-53 years, 46.7% female) were evaluated. These patients had been transfused with a median of 531 washed RBC units (IQR 244-1066) per patient over 12 years (IQR 5-18 years), most commonly for recurrent, non-severe allergic reactions. There were no transfusion reactions with unwashed RBCs aside from one patient with one episode of pruritus and another with recurrent pruritus, which was typical even with washed RBC. We decreased the mean number of washed RBC units per month by 72.9% (104 ± 10 vs. 28.2 ± 25.2; p < .0001) and saved US $100.25 per RBC unit. CONCLUSION: Washing of RBCs may be safely reconsidered in chronically transfused patients without a history of anaphylaxis. Washing should be implemented judiciously due to potential lack of necessity and logistical/operational challenges.

How do we perform intrauterine transfusions?

BACKGROUND: Intrauterine transfusion (IUT) is an invasive but critical and potentially life-saving intervention for severe fetal anemia with demonstrated improvement in outcomes. The fetus is vulnerable to hemodynamic alterations and transfusion-related adverse events; therefore, special consideration must be given to blood component selection and modification. There is widespread IUT practice variability, and existing guidance primarily relies on expert opinion and single center experiences. STUDY DESIGN AND METHODS: Experts in Maternal Fetal Medicine, Pediatric Hematology, and Transfusion Medicine from centers across the United States, collectively performing about 120 IUT annually, offer a multidisciplinary perspective on the performance of IUT and preparation of blood components. This perspective includes strategies for identifying an at-risk fetus, communicating between disciplines, determining the necessary blood volume, selecting and processing blood components, documenting the procedure in medical record, and managing the neonate. RESULTS: Identifying an at-risk fetus relies on review of the clinical history, non-invasive monitoring, and laboratory evaluation. We recommend the use of relatively fresh, group O, cytomegalovirus-safe, freshly irradiated, red blood cells (RBC) that are Hemoglobin S negative and antigen-negative for any maternal antibody, if indicated. These RBC units should be concentrated to remove additives and increase the hematocrit thus minimizing fluctuations in fetal volume status. The units intended for IUT should be labeled clearly and the documentation of transfusion differentiated in the maternal medical record. DISCUSSION: An awareness of the technical, logistical, and regulatory considerations for IUT performance will facilitate improved communication and patient care, especially when rare units of RBC are required.

Neonatal Blood Banking Practices.

There is little formal guidance to direct neonatal blood banking practices and, as a result, practices vary widely across institutions. In this vulnerable patient population with a high transfusion burden, considerations for blood product selection include freshness, extended-storage media, pathogen inactivation, and other modifications. The authors discuss the potential unintended adverse impacts in the neonatal recipient. Concerns such as immunodeficiency, donor exposures, cytomegalovirus transmission, volume overload, transfusion-associated hyperkalemia, and passive hemolysis from ABO incompatibility have driven modifications of blood components to improve safety.

How do we ensure a safe ABO recheck process?

BACKGROUND: Collecting a patient's blood in a correctly labeled pretransfusion specimen tube is essential for accurate ABO typing and safe transfusion. Noncompliance with specimen collection procedures can lead to wrong blood in tube (WBIT) incidents with potentially fatal consequences. Recent WBIT events inspired the investigation of how various institutions currently reduce the risk of these errors and ensure accurate ABO typing of patient samples. MATERIALS AND METHODS: This article describes the techniques employed at various institutions across the United States to mitigate the risk of misidentified pretransfusion patient specimens. Details and considerations for each of these measures are provided. RESULTS: Several institutions require the order for an ABO confirmation specimen, if indicated, to be generated from the transfusion medicine (TM) laboratory. Others issue a dedicated collection tube that is available exclusively from the TM service. Many institutions employ barcoding for electronic positive patient identification. Some use a combination of these strategies, depending on the locations or service lines from which the specimens are collected. CONCLUSION: The description of various WBIT mitigation strategies will inform TM services on practices that may be effective at their respective institutions. Irrespective of the method(s) utilized, institutions should continue to monitor and mitigate specimen misidentification errors to promote sustained safe transfusion practices.

Therapeutic plasma exchange in the management of stiff person syndrome spectrum disorders: a case series and review of the literature.

Background: Stiff person syndrome spectrum disorders (SPSD) are a rare group of disabling neuroimmunological disorders. SPSD often requires immune therapies, especially in the setting of inadequate response to symptomatic treatments. The safety and efficacy of therapeutic plasma exchange (TPE) in SPSD remains uncertain. Objectives: To describe the safety, tolerability, and efficacy of TPE in patients with SPSD. Design: A retrospective observational study. Methods: A retrospective review of SPSD patients seen at Johns Hopkins Hospital (JHH) from 1997 to 2021 was performed. Patient demographics/history, examination/diagnostic findings, treatment response, and TPE-related complications were recorded. Assessment for any associations between clinical characteristics, including age, sex, clinical phenotype, and time on immunotherapy, and response to TPE 3 months after treatment was performed. A subgroup of 18 patients treated with TPE at JHH and 6 patients treated with TPE at outside institutions were evaluated for any change in usage of symptomatic medications 3 months after the TPE treatment. Literature review of SPSD and TPE was also conducted. Results: Thirty-nine SPSD patients were treated with TPE (21 at JHH and 18 at outside institutions); median age 48 years, 77% female, median modified Rankin Scale 3; mean initial anti-GAD65 antibody titer was 23,508 U/mL. Twenty-four patients (62%) had classic SPS, 10 (26%) had SPS-plus, 2 (5%) had progressive encephalomyelitis with rigidity and myoclonus, and 3 (8%) had pure cerebellar ataxia. All patients were on symptomatic treatments, 30 (77%) previously received IVIg, and 3 (8%) previously received rituximab. Four patients (10%) had a TPE-related adverse event. One developed asymptomatic hypotension, another had both line thrombosis and infection, and two had non-life-threatening bleeding events. Twenty-three (59%) patients reported improvement in symptoms after TPE. Of the subgroup of 24 patients evaluated for any change in usage of symptomatic medications 3 months after the TPE treatment, 14 (58%) required fewer GABAergic symptomatic medications. Literature review identified 57 additional patients with SPSD; 43 (75%) reported temporary improvement after TPE. Conclusion: The majority of patients treated with TPE had improvement. Moreover, most patients evaluated for any change in usage of symptomatic medications after the TPE treatment no longer required as much symptomatic medications months after TPE. TPE appears safe and well-tolerated in SPSD. Further studies are needed to assess the long-term efficacy of TPE in SPSD and identify which patients may benefit the most from TPE.

Pediatric firearm injury related emergency department visits and hospitalizations: a population-based study in the United States.

Background: Firearm injury (FI) is the leading cause of death in children and adolescents in the United States (US). We describe the epidemiology of pediatric FI-associated emergency department (ED) visits and hospitalizations in the US stratified by race and ethnicity. Methods: Data on pediatric (0-17-year-olds) FI were analyzed using the 2019 Nationwide Emergency Department Sample (NEDS) and Kids' Inpatient Database (KID), the largest all-payer databases in the US for ED visits and pediatric hospitalizations, respectively. FI encounters were stratified by race and ethnicity. Poisson regression was used to identify factors associated with in-hospital mortality. Sampling weights were applied to generate nationally representative estimates. Findings: There were 7017 pediatric ED visits with FI (NEDS); 85.0% (5961/7017) were male and 73.0% (5125/7017) were adolescents (15-17 years). Overall, 5.5% (384/7017) died in the ED; 53.1% (3727/7017) of ED encounters did not result in hospitalization. There were 2817 pediatric FI hospitalizations (KID); 84.1% (2369/2817) were male and 71.6% (2018/2817) were adolescents; 51.4% (1447/2817) of FI were unintentional, 42.8% (1207/2817) were assault-related, and 5.8% (163/2817) were self-inflicted. Black children had the highest proportion (52.6%; 1481/2817) of hospitalizations among all race and ethnicities (p < 0.0001 vs. White). White children had the highest proportion of hospitalizations for self-inflicted injuries (16.6% [91/551] vs. 4.9% [25/504; p < 0.0001] in Hispanics and 1.7% [24/1481] in Blacks; p < 0.0001). The majority (56.5%; 1591/2817) of hospitalizations were patients from low-income zip codes (median annual-household-income <$44,000); 70% (1971/2817) had Medicaid as the primary insurance payer. Overall, 8.0% (225/2817) died during FI-associated hospitalizations. Self-inflicted injuries had the highest in-hospital mortality (prevalence ratio = 8.20, 95% CI = 6.06-11.10 vs. unintentional). Interpretation: Black children and children with lower household incomes were disproportionately impacted by FI resulting from assaults and accidents, while White children had the highest proportion of self-inflicted FI injuries. Public health and legal policy interventions are needed to prevent pediatric FI. Funding: US National Institutes of Health.

Managing blood supplies during natural disasters, humanitarian emergencies, and pandemics: lessons learned from COVID-19.

INTRODUCTION: The COVID-19 pandemic has resulted in a historic public health crisis with widespread social and economic ramifications. The pandemic has also affected the blood supply, resulting in unprecedented and sustained blood shortages. AREAS COVERED: This review describes the challenges of maintaining a safe and sufficient blood supply in the wake of natural disasters, humanitarian emergencies, and pandemics. The challenges, which are accentuated in low- and high-income countries, span the impact on human capacity (affecting blood donors and blood collections personnel alike), disruption to supply chains, and economic sustainability. COVID-19 imparted lessons on how to offset these challenges, which may be applied to future pandemics and public health crises. EXPERT OPINION: Pandemic emergency preparedness plans should be implemented or revised by blood centers and hospitals to lessen the impact to the blood supply. Comprehensive planning should address the timely assessment of risk to the blood supply, rapid donor recruitment, and communication of need, measures to preserve safety for donors and operational staff, careful blood management, and resource sharing.

Transfusion-transmitted babesiosis in a patient with sickle cell disease undergoing chronic red cell exchange.

BACKGROUND: Prior to laboratory-based blood donor screening for Babesia, transfusion-transmitted babesiosis (TTB) was a leading infectious risk to the blood supply in the United States. CASE REPORT: A 30-year-old man with sickle cell disease (SCD) who had been on a chronic automated red cell exchange (RCE) regimen since childhood, presented approximately 2 months after an RCE, with fever, neck pain, and photophobia. Meningitis was excluded, and he was discharged. He presented again 2 days later with persistent fever, chills, headache, fatigue, and loss of appetite. RESULTS: On examination, the patient was febrile but hemodynamically stable. Intra-erythrocytic inclusions were identified on a peripheral blood smear (<0.5%). B. microti IgM and IgG titers were >1:320 (Reference <1:20) >1:1024 (Reference <1:64), respectively. B. microti was confirmed by nucleic acid testing. The patient lived in a Babesia endemic state but had no risk factors for tick-borne acquisition. Of the 65 units he received in the preceding 6 months, 58 had been screened for Babesia. One of the donors of the 7 untested units was B. microti seropositive (titer 1:128; Reference 1: 64). The donor was asymptomatic and resided in a state in which Babesia screening was not required. He reported traveling in the year before his donation. CONCLUSION: Although rare, TTB is still possible despite regional screening, underscoring the need for provider vigilance and education, especially in non-endemic areas. Patients with SCD are particularly vulnerable given their high frequency of transfusion and complex needs requiring blood procurement from states where Babesia screening is not mandatory.

Survey of intrauterine red blood cell (RBC) transfusion practices in the United States.

BACKGROUND: A paucity of data exists about the current practice of fetal red blood cell (RBC) transfusion in the United States (US). This investigation describes intrauterine transfusion (IUT) RBC product selection and processing practices at different US institutions. METHODS: A transfusion medicine and maternal-fetal medicine (MFM) team designed a survey to interrogate and characterize RBCs utilized for IUT. This survey was distributed to seventy US institutions with fetal treatment centers (October 2020-April 2021) identified through the NAFTNet (North American Fetal Therapy Network). RESULTS: Thirty-seven institutions responded (response rate 53%, 37/70), but five were excluded for not performing IUTs. Most (84%; 27/32) performed 1-24 IUTs annually; two performed >50 IUTs/year. Group O, Rh(D) negative RBC units were always used by 66% (21/32), and 75% (24/32) provided hemoconcentrated RBCs by washing (17/24) or dry packing (6/24). Overall, 66% (21/32) targeted a hematocrit ≥75%. Fifty percent provided both leukocyte-reduced and CMV-negative RBC units. Irradiation of RBC units was performed within 6 h of issue at 63% (20/32) of sites. Most (81%, 26/32) used RBC units at <7 days of age after collection, 56% (18/32) always provided washed RBC units, while 19% (6/32) issued washed RBC only if fresh units are unavailable. Implicated maternal RBC alloantibodies were matched for 78% (25/32) of the time. The transfused volume was universally determined by the MFMs. DISCUSSION: Heterogeneity and lack of standardization exist in RBC product selection and special processing steps for IUTs in the US. Hence, the establishment of a consensus to standardize IUT protocols is needed.

Therapeutic plasma exchange practices in immune thrombocytopenia related hospitalizations: Results from a nationally representative sample.

Per the American Society for Apheresis, therapeutic plasma exchange (TPE) is a Category III indication in the management of immune thrombocytopenia (ITP). This nationally representative study evaluates TPE utilization in hospitalized adults with a primary admission diagnosis of ITP. Hospitalizations with ITP as the primary admitting diagnosis were analyzed from the 2010 to 2014 National Inpatient Sample, the largest all-payer inpatient database in the United States. Univariate and multivariable logistic regressions were used to determine clinical outcomes in ITP patients undergoing TPE. Sampling weights were applied to generate nationally representative estimates. From 2010 to 2014, there were a total of 56,149 admissions with a primary admitting diagnosis of ITP, of which 0.66% admissions (n = 372) also coded TPE. Most subjects undergoing TPE were the highest disease severity class: major (34.6%) and extreme severity (31.0%), by all-patients refined diagnoses-related groups severity of illness subclass. After multivariable analysis, underlying severity of illness remained the most significant predictor of TPE (P < .001). ITP admissions with TPE had a high rate of comorbidities (50%) and significantly longer mean length of hospital stay than those without (P < .001). TPE was reported in ~0.6% of hospitalizations with ITP as the primary diagnosis in this nationally representative sample from 2010 to 2014. TPE was performed in patients with the highest severity of underlying illness, and higher rates of comorbidities.