Kinard, Theresa N.

ABSTRACT We report a case of fulminant Clostridium perfringens septicemia complicated by massive intravascular hemolysis in a 19‐year‐old male with acute myelogenous leukemia. The patient presented with severe anemia and laboratory evidence of profound hemolysis. Despite the high mortality associated with this condition, the patient was successfully treated with broad‐spectrum antibiotics, including clindamycin, and three consecutive sessions of therapeutic plasma exchange (TPE). TPE was employed to remove circulating α‐toxin and cell‐free hemoglobin, thereby mitigating ongoing hemolysis and organ injury. This case highlights the potential role of TPE, in conjunction with appropriate antimicrobial therapy, as an intervention in C. perfringens septicemia with hemolysis.

Abstract Background: Recombinant activated factor VIIa (rFVIIa, NovoSeven®) is an FDA-approved medication for managing bleeding in patients with hemophilia A or B with inhibitors and for those with congenital factor VII deficiency. Its use has expanded off-label in the perioperative context to manage unexpected bleeding complications. However, there is still a gap in real-world data regarding institutional practices, dosing, and outcomes associated with rFVIIa. Methods: With IRB approval, we identified patients who received rFVIIa in the perioperative period between 2020 to 2024 at Mayo Clinic. A detailed chart review was conducted to gather demographic data, comorbid conditions, bleeding disorders, timing, and dosing of perioperative rFVIIa (pre-, intra-, and postoperative), along with postoperative outcomes. We focused on thrombotic and bleeding events, hospital readmissions, and return to the operating room (OR). Descriptive statistics were used for patient characteristics, rFVIIa dosing patterns, and postoperative complications. Type of surgical interventions were stratified based on UCLA perioperative risk stratifications, with a risk score of 5 equating to very high risk surgery and a score of 1 equating to very low risk surgery. Results: Of the 55 patients included, the median age at surgery was 42.3 years (SD 27.4), and 69% were male. The majority were non-Hispanic white (91%). The most common bleeding diatheses were Factor VII deficiency (54.6%), Factor VIII inhibitor (12.7%), and Glanzmann thrombasthenia (7.3%). Less frequent conditions included Hemophilia A (3.6%) and Hemophilia A with inhibitors (3.6%). Among patients with Factor VII deficiency, mild deficiency accounted for 65.9% of cases, followed by severe (19.5%) and moderate (14.6%) forms. Adjunctive medications to control bleeding included emicizumab, FEIBA, and rituximab. Mean estimated blood loss was 136 mL (SD 211 mL), and mean length of stay was 5.7 days (SD 6.4). Surgical risk strongly correlated with perioperative outcomes: blood loss increased from 19 mL in very low-risk surgeries to 352 mL in very high-risk surgeries, while mean length of stay increased from 4.5 days (risk 1) to 19 days (risk 4) and 11 days (risk 5). Actual rFVIIa dosing ranged from 7.2 to 7211.5 mcg/kg per dose, with a median of 67.4 mcg/kg and a mean of 852.8 mcg/kg, reflecting variability in clinical practice. When stratified by surgical risk, the highest median doses were observed in very low- and low-risk surgeries (84.4 and 86.8 mcg/kg, respectively), while very high-risk surgeries had the lowest median dose (30.0 mcg/kg). In the postoperative period, thrombotic events did not occur in the first 90 days but were documented in 1.8% of patients between 90 and 365 days and in 1.8% after 365 days. Bleeding complications were frequent and demonstrated predominance in the immediate post-op period. Within the first 30 days after surgery, 18.2% of patients experienced bleeding complications, with 3.6% classified as major and 14.5% classified as minor, based on ISTH criteria. Between 30 and 90 days, bleeding complications occurred in 9.1% of patients (3.6% major and 5.5% minor), between 90 and 365 days, bleeding was observed in 10.9% of patients, all of which were minor, and beyond one year, bleeding complications were documented in 23.6% of patients, with 3.6% major and 21.8% minor. Readmissions were also common and followed a similar time distribution. In the first 30 days, 7.3% of patients had readmissions related to the prior surgery, and 3.6% had unrelated readmissions. Between 30 and 90 days, 3.6% of readmissions were related and 3.6% were unrelated. Between 90 and 365 days, 3.6% were related and 14.5% were unrelated to the initial procedure. Returns to the OR occurred in 1.8% of patients between 30 and 90 days and in 1.8% between 90 and 365 days. Conclusions: In conclusion, perioperative rFVIIa was most frequently used for Factor VII deficiency but was also administered to patients with Factor VIII inhibitor and Glanzmann's thrombasthenia, as well as several rare congenital and acquired bleeding disorders. Postoperative thrombotic events were rare, while ISTH-defined bleeding complications and readmissions were common. Most bleeding complications were minor, but their frequency was highest in the early postoperative period and again beyond one year. High-risk surgeries were associated with greater blood loss, prolonged hospitalization, and a higher burden of postoperative complications.

Abstract Background Thrombotic Thrombocytopenic Purpura (TTP) is a rare, typically acquired disorder due to an immune-mediated deficiency of ADAMTS13, a metalloprotease responsible for cleaving large multimers of von Willebrand Factor (vWF). In the absence of ADAMTS13 activity, ultra-large vWF multimers accumulate, promoting widespread platelet aggregation and microvascular thrombosis. This consumptive cascade leads to thrombocytopenia, microangiopathic hemolytic anemia, fever, neurological symptoms, and rarely renal dysfunction. Although therapeutic plasma exchange (TPE) has long been the cornerstone of TTP treatment, the FDA approved Caplacizumab as a first-line treatment for TTP in 2019. This drug is a bivalent single-domain antibody that binds to the A1 domain of vWF and prevents its interaction with platelets, thus effectively interrupting the pathogenic cascade, which is associated with a risk of bleeding. Methods We conducted a retrospective cohort study using the TriNetX Global Collaborative Network, comprising data from 152 healthcare organizations. Adults (≥18 years) with a diagnosis of TTP who received Caplacizumab plus TPE were compared to patients with TTP who received TPE alone. 1:1 propensity score matching (PSM) was performed to balance characteristics between cohorts. The primary outcomes assessed were all-cause mortality and major bleeding events over a period of 1 month. Results A total of 4084 patients with TTP were identified, of whom 356 received caplacizumab with TPE and 3728 received TPE. After PSM, 2 balanced cohorts were created: C+P (Caplacizumab + TPE), P only (TPE), each comprising 356 patients. The average age in C+P and P only, after PSM, was 50.4 +/- 16.2 and 50.8 +/- 16.2 years, respectively. Females formed 65.7% of both C+P and P only, and males accounted for 28.4% and 28.7% of C+P and P only, respectively. 2.8% patients in C+P and 7.06% patients in P only had all-cause mortality at the end of 1 month. One-month all-cause mortality was significantly lower in C+P (2.8%) compared to P only (7.06%), with an odds ratio (OR) of 0.385 (95% CI 0.182 to 0.814, p=0.010). Upon assessment of bleeding outcomes, no statistically significant risk difference was noted between the 2 groups, with the odds ratio being 0.974 (95% CI 0.399 to 2.379, p=0.954). Conclusion Our large database study suggests that the addition of caplacizumab to standard TPE therapy is associated with a reduction in one-month all-cause mortality in patients with TTP, without a corresponding increase in major bleeding. However, given the lack of granular clinical data, such as contraindications to caplacizumab use, it is possible that patients who received TPE alone were inherently at a higher risk. As such, while these findings support the potential benefit of early caplacizumab use, they should be interpreted with caution and warrant prospective validation to confirm causality and assess long-term outcomes.

Abstract Background Alcohol biomarkers including ethyl glucuronide (EtG) and phosphatidylethanol (PEth) are ordered frequently in clinical and forensic settings including solid organ transplantation. PEth provides a long detection window but can be insensitive to light drinking. In contrast, EtG and ethyl sulfate (EtS) can be elevated after light alcohol consumption and might complement PEth testing. Methods Urine EtG/EtS and whole blood PEth results were evaluated from all clinically-ordered testing between 2014 and 2024. PEth and EtG/EtS confirmation were performed by liquid chromatography tandem mass spectrometry at two reference laboratories, using cutoffs: Lab A, PEth 20 ng/ml, EtG and EtS 500 and 250 ng/ml; Lab B, PEth 10 ng/ml, EtG and EtS 250 and 100 ng/ml. Only Lab B performed EtG screening by immunoassay, using a 500 ng/ml cutoff. Results Phosphatidylethanol was positive in 1269 (15.6%) of 8131 samples, compared to 769 (6.7%) confirmed EtG/EtS positives from 11 555 samples. EtG screening (n = 9668) was positive in 743 (7.7%) samples, of which 30 (4.0%) confirmed negative (false positives); the screen was indeterminate in 267 (2.8%) samples, 66 of which confirmed positive and 172 negative. Of 3132 paired PEth and EtG samples, 2887 (92.2%) were concordant, 224 (7.2%) were PEth-positive, and 21 (0.7%) were EtG-positive. PEth was significantly more sensitive in paired samples (P < .001), even after accounting for potential confounders such as transfusion. Limiting testing to PEth would have correctly identified alcohol consumption in 331 of 373 (88.7%) instances versus EtG/EtS in 149 (39.9%), and reduced charges by >$720 000 USD. Discussion Phosphatidylethanol outperformed EtG/EtS in detecting alcohol consumption in a predominantly abstinent transplant population. Compared to PEth, EtG/EtS had lower overall positivity and poorer sensitivity in paired samples; additionally, EtG screening demonstrated false positives and indeterminate results. EtG testing provided little added value beyond PEth in this population, and did not warrant the increased cost of performing both tests.

The use of normothermic machine perfusion (NMP) over static cold storage in liver transplantation has been shown to reduce posttransplant risks of early allograft dysfunction, primary nonfunction, and ischemic cholangiopathy, and its increasing use has played a role in the expanded utilization of marginal livers. While studies have demonstrated improved clinical outcomes using NMP over static cold storage preservation, real-time intraoperative data reflecting the quality and viability of NMP livers is limited. This retrospective, single-center study compared NMP versus static cold storage livers in first-time recipients of liver transplants through the evaluation of synthetic coagulation function as measured by thromboelastography and conventional coagulation testing. Secondarily, transfusion utilization between the 2 cohorts was reviewed. One hundred eighty-six recipients of liver transplants receiving allografts from donors after circulatory death were included in the study, of which 99 (53%) allografts were preserved in static cold storage, and 87 (47%) allografts were placed on the TransMedics Organ Care System. Study findings showed NMP livers supported with the TransMedics Organ Care System were associated with increased synthetic coagulation function and less excess fibrinolysis in the postreperfusion period compared to static cold storage livers, and that these findings were better reflected in real-time with thromboelastography monitoring versus conventional coagulation testing. Following reperfusion, there was a significant decrease in the transfusion of blood products in the NMP group compared with that in the static cold storage group. Overall, we determined that the use of intraoperative thromboelastography can provide real-time data to assess one aspect of reperfusion liver quality and viability.

AbstractIntroductionPhosphatidylethanol (PEth) is a long‐term marker of alcohol consumption used frequently in clinical scenarios such as liver transplant evaluation. Recent cases have demonstrated that packed red blood cell (pRBC) transfusion creates the potential for artificial elevation or decrease of observed PEth concentrations in recipients. Very little is known about the prevalence or stability of PEth in pRBCs.MethodsApheresis and whole‐blood (WB) donations were tested for PEth using liquid chromatography – tandem mass spectrometry with limit of quantitation 10 ng/mL. Units were stored under routine blood bank conditions to evaluate the stability of PEth and the impact of irradiation.ResultsOver 40% of apheresis and WB donors had PEth ≥10 ng/mL (maximum observed 587 ng/mL). As WB units were processed into component pRBCs, PEth concentrations increased and were higher than donor WB levels (EDTA sample) prior to collection (maximum observed 711 ng/mL). Storage for up to 5 weeks post donation resulted in mean 17.3% decrease in PEth‐positive units; in contrast to a prior report, we observed no PEth formation in units with negative (<10 ng/mL) baseline concentrations. Irradiation of pRBCs did not substantially affect PEth concentrations in either PEth‐positive or PEth‐negative units.DiscussionPEth concentrations in healthy blood donors may potentially confound alcohol use or abstinence assessment in pRBC recipients. Transfusion medicine services and clinical practices such as transplantation and behavioral medicine should recognize this phenomenon and collaborate on testing protocols to appropriately interpret PEth in pRBC recipients.

Abstract This manuscript describes a novel approach for treating patients with long‐term sequelae from hemoglobin Evans (Hb Evans). After instituting conservative therapies for approximately 2 years, our patient's symptoms continually worsened. Therefore, we performed red blood cell exchange (RBCx) to reduce his Hb Evans percentage and his co‐existing elevation of methemoglobin. Our assumptions of clinical benefit were based on our collective experience performing RBCx for patients with sickle cell disease. After the first exchange, pre‐ and post‐laboratory results supported our approach and the patient experienced marked improvement in his clinical signs and symptoms. This report provides preliminary proof of principle for the use of RBCx to treat Hb Evans and other non‐Hb S hemoglobinopathies.

Abstract Introduction: Acquired thrombotic thrombocytopenic purpura (aTTP) due to an acquired deficiency in the enzyme ADAMTS13 leads to ultra-large von Willebrand multimers, thrombocytopenia and microangiopathic hemolytic anemia. Complications include microvascular and macrovascular thrombosis. We present an unusual case of a patient with a history of refractory aTTP who experienced relapsed aTTP following COVID-19 vaccine. Case Description: A 57-year-old African-American male with a history of refractory aTTP experienced a relapse following 3 years of remission after receiving COVID-19 vaccination. The patient was initially diagnosed with aTTP in 2016, after presenting with symptoms of dark urine, mild headaches and transient episodes of aphasia and paresthesia. Due to symptoms and persistently low ADAMTS13 levels, he required prolonged and extensive treatment including over 5 weeks of daily therapeutic plasma exchange (TPE), followed by gradual reduction in frequency of TPE sessions, as well as trials of rituximab, eculizumab, steroids, mycophenolate mofetil and bortezomib. Ultimately, he achieved remission after 9 months of intermittent TPE, 3 months of weekly bortezomib 1 mg/m 2, mycophenolate mofetil up-titrated to 1,750 mg twice daily, and then slowly tapered off over a 2-year period. The patient was doing well for 3 years without manifestations of aTTP (2 years off all therapeutics), until he developed a petechial rash 7 weeks after receiving the second dose of the Moderna COVID-19 vaccine. He was found to have acute thrombocytopenia with platelets of 38 x 10 9/L (normal range 135-317 x 109/L), from a baseline of 200-300 x 10 9/L. He was referred to the emergency department, where additional labs were notable for mildly elevated LDH of 508 U/L (normal range 122-222 U/L), hemoglobin of 12.4 g/dL (normal range 13.2-16.6 g/dL), creatinine at baseline, and peripheral blood smear showing 1-3 schistocytes per high-powered field. ADAMTS13 activity level was t &lt;5% (normal &gt;/= 70%), with positive ADAMTS13 inhibitor screen and titer of 1.5 (normal &lt;0.4), consistent with relapsed aTTP. The patient was admitted to the hospital, and initiated on daily TPE, with steroids and diphenhydramine prior to each TPE session. He quickly improved with TPE alone , but given his history of refractory aTTP, he was discharged on weekly rituximab for 4 weeks and caplacizumab 11 mg daily for 30 days. His platelets remained stable within the upper limit of normal during his 30 day course of caplacizumab. However, 3 weeks after completion of caplacizumab, he had an acute drop in his platelets to 23 x 10 9/L. His ADAMTS13 level was again found to be &lt;5%, and inhibitor level was the highest that it had ever been at 11.4. He was again hospitalized and underwent 8 sessions of daily TPE, as well as re-initiation of caplacizumab, mycophenolate mofetil 500 mg bid (with increasing taper), and a prednisone taper. Intravenous Cyclophosphamide 750 mg/m 2 was also added every 3 weeks. With this regimen, patient's platelet count normalized and remain stable, and his ADAMTS13 activity level has reached 52-59%. Discussion: Cases of vaccine-induced immune thrombotic thrombocytopenia (VITT) have been described as a complication following vaccination with formulations containing replication-defective adenoviral vectors (AstraZeneca-Oxford and Johnson&Johnson COVID-19 vaccines)(Arepally and Ortel 2021, Simpson, Shi et al. 2021). VITT and aTTP are both immune-mediated, however, VITT is distinct and pathogenically linked to autoimmune heparin-induced thrombocytopenia (HIT), given the presence of anti-platelet factor 4 antibodies in these patients, whereas aTTP is due to reduction in ADAMTS13 level, secondary to an antibody inhibitor of ADAMTS13 (Arepally and Ortel 2021). Recently, cases have been reported of de novo aTTP developing shortly after COVID-19 vaccination with all available vaccines, except the Moderna (mRNA-1273) vaccine (Al-Ahmad, Al-Rasheed et al. 2021, de Bruijn, Maes et al. 2021, Maayan, Kirgner et al. 2021, Ruhe, Schnetzke et al. 2021, Waqar, Khan et al. 2021, Yocum and Simon 2021). Additionally, cases of relapsed aTTP have been described following only the BNT162B2 (Pfizer-BioNTech) vaccine (Maayan, Kirgner et al. 2021, Sissa, Al-Khaffaf et al. 2021). This is the first case, to our knowledge, reported in the literature of aTTP following vaccination with Moderna's mRNA-1273 vaccine. Disclosures No relevant conflicts of interest to declare.

Abstract Background: Sickle cell anemia (SCA) is a genetically inherited disorder that can lead to severe sequelae in any organ system. The most clinically devastating complications, e.g. stroke, are managed with chronic red blood cell (RBC) transfusions as curing the underlying SCA is often not an option. Chronic RBC exchange (RBCx), is an effective alternative to simple transfusions and often performed every 4-5 weeks. Isovolemic Hemodilution-Red Blood Cell Exchange (IHD-RBCx) is a modified RBCx method used at UT Southwestern Medical Center (UTSW) and increases the time interval between transfusions, i.e. inter-procedure interval (IPI), up to 9 weeks while maintaining the desired hemoglobin S targets at safe levels. This minimizes the overall lifetime procedures and blood exposures. The standard operating procedure for IHD-RBCx is published (Matevosyan et al, 2012). However, we observed IPI variability between patients in this chronic IHD-RBCx program. We sought to analyze hematologic characteristics in a cohort of adult SCA patients that may be associated with this noted variability. Methods: This IRB approved cross-sectional study evaluated medical and blood bank records of adult patients with SCA, i.e. hemoglobin SS or Sβ0 thalassemia genotypes, undergoing chronic IHD-RBCx at UTSW adult hospital sites between January 1, 2012 and December 31, 2013. Excluded participants were those with autoimmune disease, non-compliance with IHD-RBCx leading to delays > 7 days, or use of hydroxyurea or steroids within four months of the study period. Patients with < 5 exchanges were excluded as several procedures are needed to determine baseline IPIs. The primary indication for IHD-RBCx was secondary stroke prevention. Three subjects had alternative indications (i.e. recurrent severe acute chest syndrome that failed hydroxyurea therapy, intractable pain and severe anemia ineligible for iron chelation due to end-stage renal disease). Median values during the 2 year study were determined for the IPI, laboratory, and RBC properties for use in subsequent analyses. Correlation and multiple regression analyses were performed to determine variables predictive of IPI. Results: Twenty-four SCA patients in this chronic IHD-RBCx transfusion program met inclusion criteria of which 14 (58.3%) were female with age range 18-41 years. Three subjects had incomplete data. The median number of packed RBC (pRBC) units per IHD-RBCx was 8 (range: 6-11 units). The median volume per unit of pRBCs was 304.5 mL (range: 298.8-326.5 mL) with average age of the pRBCs 5.8 days ± 0.7 days. The median IPI was 55.8 days (range: 36.0-65.5 days). The strongest correlation with IPI was the change from the mid to post-procedure hemoglobin and hematocrit values, r=0.56, p=0.005 and r=0.57, p=0.003, respectively. Participants with documented direct antiglobulin test positivity (n=7), compared to those who remained negative (n=16), had 4.9 days increased IPI. This difference was not statistically significant, p=0.19. ABO differences in blood type also did not show statistical significant differences. However, A+ subjects had a 58 day interval compared to 51, 52, 53 days for B+, O+, O- respectively (Figure). In multiple regression models, log blood urea nitrogen (BUN) and post-procedure white blood cell count (WBC) were found to be independent predictors of IPI, beta=-11.3, p=0.04 and -2.1, p=0.03 respectively, with adjusted R2=0.31. Conclusions: Chronic IHD-RBCx effectively treats severe SCA complications. Discontinuing transfusions lead to repeat stroke events or the recurrence of disease manifestations making chronic transfusion programs an indefinite therapy. Outside of the expected correlation between the IPI and hemoglobin/hematocrit, WBC and BUN were found to have negative associations with IPIs. The decrease in WBCs is likely due to the direct clearing effect by the operating system. The association between BUN and IPI may imply relationship with renal function. Interestingly, association with creatinine was not statistically significant. The study is limited by the small sample size. Future studies of similar cohorts should prospectively evaluate target mechanisms which may lead to interventions that can minimize lifetime blood exposures given the growing demands for continued RBCx in severe SCA. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.