Adamski, Jill

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 <5% (normal >/= 70%), with positive ADAMTS13 inhibitor screen and titer of 1.5 (normal <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 <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 Introduction: The management of bleeding associated with direct oral anticoagulants (DOACs) is challenging and associated with high risk of morbidity/mortality despite the use of various reversal agents (Gomez-Outes et al. 2021). Routine tests cannot determine the level of DOAC anticoagulation and reversal agents carry potential prothrombotic complications (Garcia & Crowther 2021). We present an unusual case of a patient requiring emergent surgery with significant post-op bleeding due to profoundly delayed apixaban elimination. Case Description: A 63-year-old female presented to the emergency department (ED) with a 10-day history of worsening abdominal pain, distension, nausea and constipation. Her past medical history was notable for right sided heart failure, COVID-19 pneumonia requiring intubation, tissue mitral valve replacement, and post-op atrial fibrillation for which she was prescribed apixaban 5 mg BID. Her last dose of apixaban had been the night prior to ED presentation. In the ED, a CT of the abdomen revealed a 6 cm partially obstructing lesion involving the mid-sigmoid colon. Findings were consistent with evolving peritonitis and the patient underwent an emergent exploratory laparotomy, sigmoid resection, and end colostomy. Pre-op labs revealed WBC 12.4 x10 9/L, hemoglobin (hgb) 9.2 g/dL, and platelets 318 x10 9/L. Coagulation studies revealed a PT of 28 sec and INR of 2.5. The patient was given prothrombin complex concentrate (PCC) 25 units/kg and 1 mg of vitamin K prior to surgery. Postoperatively, the INR remained elevated, 2.0, and her hgb downtrended from 8.8 g/dL to 7.8 g/dL. On post-op day 1 the patient became hypotensive, with increased abdominal pain/distension, she also started bleeding from her ostomy. The INR was 2.4 and her hgb dropped to 6.0 g/dL. Red blood cells were given along with FFP, vitamin K and a 2 nd dose of PCC. The patient continued to decline, was transferred to the ICU where she was intubated and placed on CRRT. Hematology was consulted for the persistently prolonged PT/INR in the setting of bleeding despite multiple interventions to correct the INR. The patient's last dose of apixaban was ~48 h prior to ICU admission. A rapid heparin anti-Xa assay was performed and upon comparison with an in-house nomogram the result, 1.78 IU/mL, correlated to an apixaban dose between 180-200 ng/ml (average peak levels 2-4 h after administration are 171 ng/mL). This result was confirmed the following day by an apixaban anti-Xa assay, 190 ng/mL. A repeat test performed 11 h later showed a minimal decrease in apixaban indicating impaired clearance. Therapeutic plasma exchange (TPE) was considered for rapid removal of apixaban. We performed a 1.0 plasma volume exchange, using plasma as the replacement fluid, to remove apixaban. Pre and post TPE drug levels were 172 and 108 ng/mL, respectively. Due to an elevated apixaban level the next day, a second TPE was performed which dropped the level to 87 ng/mL. The patient began to improve clinically, with hgb stabilization ~10 g/dL. She was extubated and transferred to a medical floor for further management. Apixaban levels were still measurable, 16 ng/mL, on post op day 8, 11 days after her last dose. Discussion: Apixaban is a highly protein-bound drug (~90%) that is rapidly absorbed in the small intestine with a large Vd (21 L) and a t1/2 of ~12 h. Elimination primarily occurs through the fecal route (Byon et al. 2019). The factors impairing the elimination of the drug in this patient were the following: 1. Pre-op constipation resulting in 10 days without a bowel movement; 2. Minimal bowel function post-op; and 3. Renal failure requiring CRRT after admission to the ICU. This case illustrates the profound effect intestinal obstruction/dysfunction can have on apixaban clearance. It also highlights the importance of laboratory test interpretation when managing coagulopathic patients. TPE is an effective way to remove drugs with high protein binding affinity (Mahmoud et al. 2021). TPE significantly reduced apixaban levels in our patient allowing for hemostasis and clinical improvement. To our knowledge, there are only two case reports regarding the effect of TPE on DOACs, one for apixaban, the other rivaroxaban (Hodulik et al. 2019). Conclusion: TPE can be considered as an option for rapid clearance of apixaban, or other highly protein bound anti-Xa inhibitors, in the setting of delayed elimination or when specific reversal agents are not safe/available. Disclosures No relevant conflicts of interest to declare.

AbstractBackgroundImmunomodulatory strategies in heparin‐induced thrombocytopenia (HIT) include the use of intravenous immune globulin (IVIG) and therapeutic plasma exchange (TPE). The optimal application of these therapies is unknown and outcomes data are limited. We investigated treatment categories and laboratory and clinical outcomes of IVIG and/or TPE in HIT with a systematic literature review.Study Design and MethodsWe searched MEDLINE, Embase, and Web of Science through December 2019 for studies combining controlled vocabulary and keywords related to thrombocytopenia, heparin, TPE, and IVIG. The primary outcome was treatment indication. Secondary outcomes were platelet recovery, HIT laboratory parameters, heparin re‐exposure, and post‐treatment course. Case‐level data were analyzed by qualitative synthesis.ResultsAfter 4241 references were screened, we identified 60 studies with four main categories of IVIG and/or TPE use as follows: (a) treatment of refractory HIT (n = 35; 31%); (b) initial therapy (n = 45; 40%); (c) cardiopulmonary bypass surgery (CPB; n = 30; 27%); and (d) other (n = 2; 2%). IVIG was most commonly used for the treatment of refractory HIT while TPE was primarily used to facilitate heparin exposure during CPB. Both IVIG and TPE were equally used as initial therapy. Heparin re‐exposure occurred without thrombotic event in 29 TPE‐treated patients and three IVIG‐treated patients.ConclusionIn patients with HIT, both TPE and IVIG are used for initial therapy or treatment of refractory HIT. However, TPE is more commonly used in patients undergoing CPB. Prospective studies may help clarify which treatment is indicated in HIT population subsets.

Abstract Since its emergence as a novel therapy for cutaneous T-cell lymphoma in 1987, extracorporeal photopheresis (ECP) has gained popularity in the fields of solid organ and stem cell transplantation (Perotti et al Transfus Apher Sci 2015). Though ECP is thought to be associated with few adverse effects, we have anecdotally noted that some patients treated with ECP develop iron deficiency anemia. Anemia has been reported in ECP literature at an incidence of anywhere from 0% to 24.5%, however, the etiology of the anemia has not been described (Quaglino et al Int J Dermatol 2013, Flowers et al Blood 2008, Jaksch et al J Heart Lung Transpl 2012, Dignan et al Bone Marrow Transpl 2014). We performed a retrospective chart review to further investigate the magnitude of this potential adverse effect. Adult patients receiving ECP for any indication at Mayo Clinic Hospital-Rochester were eligible for inclusion. Patients with pre-existing iron deficiency anemia (IDA) or physiologic and/or pharmacologic reasons for altered iron homeostasis were excluded from analysis. The primary endpoint was to describe the cumulative incidence of IDA at one year of ECP therapy, utilizing Kaplan-Meier methodology. We defined IDA as a hemoglobin < 12 g/dL (females) or < 14 g/dL (males), plus any of the following: MCV < 80 fL, ferritin < 11 mcg/L, iron < 35 mcg/dL (females) or < 50 mcg/dL (males), total iron binding capacity > 400 mcg/dL, or percent saturation <14%. Secondarily, we aimed to describe the proportion of patients who underwent further diagnostic evaluation of IDA and those that were initiated on iron supplementation for IDA. Patients were followed for the primary endpoint until diagnosis of IDA, death, or date of last ECP session; those who did not develop IDA were censored at the date of last follow-up. Between January 1, 2006 and July 1, 2015, a total of 120 adult patients were treated with ECP at Mayo Clinic in Rochester, MN; 80 patients met inclusion criteria. For the remaining 40 patients, patients were excluded for recent history of transfusions and/or phlebotomy (n=27), incomplete documentation (n=7), IDA at baseline (n=3), or potentially confounding past medical histories (n=3). Treatment of graft-versus-host disease (GVHD) was the foremost ECP indication in our cohort, accounting for 63.8% of our patients. Patients also received ECP for treatment of cutaneous T-cell lymphoma, treatment of solid organ transplant rejection, and other indications (25%, 7.5%, and 3.8%, respectively). Mean age was 55.6 years, 38.7% were female, and the median duration of ECP therapy was 344 days (IQR 130 - 755 days). At 1 year from the start of ECP therapy, the cumulative incidence of IDA in our cohort was 21.1% (95% CI 9% - 31.6%; Figure 1). At 4 years from the start of ECP therapy, the cumulative incidence of IDA was 49.1% (95% CI 26.4% - 64.8%). Of those that developed an IDA at any time during ECP therapy, 6/20 (30%) underwent invasive diagnostic procedures (colonoscopy and/or upper endoscopy) to evaluate the etiology of the IDA. Iron supplementation was initiated in 18/20 (90%) patients; hemoglobin returned to normal in 8 patients (44.4%) based on available follow-up. These data indicate that a substantial number of patients develop IDA while receiving ECP therapy; a finding which may lead to more prompt recognition and treatment of IDA in patients receiving ECP, and perhaps spare expensive diagnostic procedures. Figure 1. Kaplan-Meier Curve of Cumulative Incidence of IDA During ECP Therapy Figure 1. Kaplan-Meier Curve of Cumulative Incidence of IDA During ECP Therapy Disclosures No relevant conflicts of interest to declare.

BACKGROUNDPatients requiring chronic apheresis treatments typically lack sufficient peripheral venous access to support long‐term therapy. Historically, central venous tunneled catheters, septum‐bearing subcutaneous ports, and fistulas were used to obtain required blood flow rates for apheresis procedures. In 2017, the US Food and Drug Administration approved the first intravascular device specifically designed for apheresis therapy, the PowerFlow Implantable Apheresis IV Port.METHODSSeveral preimplementation meetings with key hospital stakeholders were held to determine the most efficient and safest strategy for integrating the PowerFlow device into our practice. Interventional radiologists implanted the apheresis port in patients meeting specified criteria. Performance metrics and adverse events were evaluated over a 2‐year period, July 2017 through June 2019.RESULTSEighteen patients underwent apheresis therapy using the PowerFlow port. The most common apheresis therapy provided was extracorporeal photopheresis, followed by therapeutic plasma exchange and low‐density lipoprotein apheresis. Flow rates up to 90 mL/min were obtained; the rates were limited by patient tolerance for the apheresis procedure. Complications included infection, obstruction due to fibroblastic sleeve, and migration of the vascular device. The estimated risk of PowerFlow‐associated bloodstream infection in the study population was 0.18 per 1000 intravascular device days.CONCLUSIONThe PowerFlow Implantable Apheresis IV Port can achieve flow rates necessary for all apheresis therapies and is a promising alternative vascular access device for patients undergoing apheresis.

AbstractBackgroundExtracorporeal photopheresis (ECP) is associated with few adverse effects. We have anecdotally noted patients treated with long‐term ECP develop iron deficiency anemia (IDA).MethodsWe performed a retrospective chart review of adult patients who received ECP for any indication at Mayo Clinic Rochester and Mayo Clinic Arizona. The primary objective was to describe the cumulative incidence of IDA at 1 year of ECP therapy.ResultsA total of 123 patients were eligible for analysis. Graft‐vs‐host disease was the most common indication for ECP (n = 76, 61.8%). At 1 year of ECP therapy, the cumulative incidence of IDA was 24.1% (95% CI, 14.2%‐32.9%). At 5 years, the cumulative incidence of IDA was 68.3% (95% CI, 38%‐83.8%). Risk factors for the development of IDA included: cumulative number of ECP sessions (HR 1.34, 95% CI, 1.05‐1.73 per 10 additional sessions, P = .022), an indication for ECP of solid organ transplant rejection (compared to cutaneous T‐cell lymphoma, HR 5.46, 95% CI, 2.06‐14.49, P < .001), and proton pump inhibitor use at baseline (HR 2.15, 95% CI, 1.1‐4.21, P = .03). Iron supplementation was initiated in 29 of 37 evaluable patients who developed IDA, with a cumulative incidence of supplementation in 77.2% patients within 3 months of recognition of IDA (95% CI, 55.8%‐88.3%). Hemoglobin normalized in 50.1% of patients started on iron supplementation for IDA within 7 months (95% CI, 25.2%‐66.7%).ConclusionsIron deficiency anemia is common in patients receiving long‐term ECP and occurs throughout ECP therapy. IDA resolved with iron supplementation in half of patients.

AbstractMany vascular access options, such as subcutaneous ports, are currently on the market for use in both medication infusion and for procedures, such as therapeutic plasma exchange and extracorporeal photopheresis. We compared the cost and time necessary to complete apheresis procedures using either Angiodynamic's Vortex or Bard's PowerFlow subcutaneous ports by reviewing our experience on two patients undergoing long‐term apheresis treatments with at least 10 procedures with each type of port. We analyzed the cost of needles and thrombolytic therapy, staff time, overall procedure length, and the total time the patient was in the apheresis unit. We also compared flow rates and alarm rates between the two ports. In this small pilot study, use of the PowerFlow port resulted in significant cost and time savings, with mixed results for flow rates. Our results need to be confirmed in a larger patient population prior to recommending wide implementation of Bard's PowerFlow port.

Extracorporeal photopheresis is an immunomodulatory therapy indicated for patients with cutaneous T‐cell lymphoma, graft‐versus‐host disease, and heart or lung allograft rejection. Whole blood from the patient is drawn into the photopheresis instrument where it is separated into its components. Plasma, red blood cells, and the treated buffy coat are subsequently returned to the patient. Consistent, adequate blood flow is necessary to successfully complete the procedure. Vascular access options for photopheresis include peripheral vein cannulation, tunneled central venous catheters, and subcutaneous ports. Photopheresis is a very safe procedure; however, the complications and impact on the patient's quality of life associated with vascular access devices can be significant.