Caudill, Jonathan S.

Abstract BACKGROUND: Coagulation factor XIII deficiency, in either its acquired or inherited form, is a rare cause of abnormal bleeding. In patients with Factor XIII (F XIII) deficiency, recommended means of factor replacement include infusion of fresh frozen plasma (FFP), cryoprecipitated plasma (Cryo), or F XIII concentrates1. Comparisons of F XIII concentration in FFP and Cryo are not well defined. To aid management of F XIII deficiency, we measured F XIII activity and antigen in FFP and Cryo. In addition, we determined concentrations of fibrinogen, factor VIII (F VIII) and von Willebrand factor (VWF), including antigen (VWF:Ag), ristocetin cofactor activity (VWF:RCo) and collagen binding activity (VWF:CB). STUDY DESIGNS AND METHODS: 10 bags each of FFP and of Cryo from blood group O donors obtained from the Mayo Clinic Division of Transfusion Medicine blood bank, were analyzed. F XIII activity was assayed by ELISA detecting activated F XIII-mediated amine incorporation into solid phase fibrinogen (Pefakit, Pentapharm). F XIII antigen was measured using radial immunodiffusion (The Binding Site). Fibrinogen was measured by Clauss kinetic clotting assay (Fibriquik, Biomerieux) and also by endpoint delta OD derived from the prothrombin time (ACL, Instrumentation Lab). F VIII was measured by 1-stage APTT-based assay; VWF:Ag by automated LIA (Diagnostica Stago); VWF:RCo by aggregometry of washed platelets; and VWF:CB by ELISA (Corgenix). RESULTS: Mean concentrations of F XIII activity were 60 U/bag (+/−30) in Cryo and 288 U/bag (+/− 77) in FFP. F XIII antigen concentrations paralleled the activity results and are depicted in Table 1, which also includes results for the other analytes. The mean fluid volumes of Cryo and FFP were 21.3 ml/bag (+/− 2.7) and 245 mL/bag (+/− 29), respectively. Table 1. Comparison of Hemostatic Components in Cryoprecipitated Plasma (Cryo) versus Fresh Frozen Plasma (FFP) Cryoprecipitate Fresh Frozen Plasma Component Mean (SD) Mean (SD) Factor XIII activity 60 U/bag (+/− 30) 288 U/bag (+/− 77) Factor XIII antigen 0.65 mg/bag (+/− 0.23) 2.36 mg/bag (+/− 0.76) Factor VIII 133 U/bag (+/− 36.5) 265 U/bag (+/− 83) Fibrinogen Clauss 184 mg/dl (+/− 44) 725 mg/dl (+/− 199) Fibrinogen ACL 319 mg/dl (+/− 76) 864 mg/dl (+/− 327) VWF:Ag 181 U/bag (+/− 53) 218 U/bag (+/− 70) VWF:RCo 168 U/bag (+/− 34) 221 U/bag (+/− 65) VWF:CB 165 U/bag (+/− 40) 208 U/bag (+/− 71) Bag volume 21.3 ml/bag (+/− 2.7) 245 ml/bag (+/− 29) CONCLUSION: In contrast to some of the other cryoprecipitable coagulation proteins, F XIII is only mildly enriched in Cryo when compared with FFP (about 2- to 3-fold). Although both products are practical means of F XIII replacement, and F XIII is somewhat enriched in Cryo, FFP may be a preferred product for F XIII replacement when infusion volume is not a major consideration (eg, in adults versus small children) and risks of exposure to multiple donors are considered. While Cryo is no longer recommended as the product of choice for VWF (or F VIII) replacement, our studies also demonstrate that Cryo is significantly enriched in VWF (which is not routinely assayed as a quality control measure for Cryo, in contrast to requirements for F VIII and fibrinogen content).

Abstract Background: Coagulation factor V (FV) is an essential cofactor of the prothrombinase complex, catalyzing conversion of prothrombin to thrombin. Severe FV deficiency is a rare coagulation defect with a prevalence in the general population of approximately 1 in 1,000,000 and a variable bleeding risk (Asselta R et al. J Thromb Haemostas 2006). Genetic mutations underlying a FV-deficient hemorrhagic diathesis have been described in a limited number of cases, display considerable allelic heterogeneity, and have been due to point mutations in the FV gene located at chromosome 1q23. Here, we report a 15 year-old girl with psychomotor delay, CNS abnormalities, and a solitary left kidney - features consistent with a congenital 1q deletion including band 1q23 - who was found to have severely reduced plasma FV activity after a routine preoperative laboratory evaluation prior to an elective spinal stabilization surgery revealed a mildly prolonged prothrombin (PT, 13.2 seconds; normal 8.4 – 12 seconds) and activated partial thromboplastin (aPTT, and 38 seconds; normal 21 – 33 seconds) time. She had undergone minor surgical procedures in the past without reports of significant bleeding, and her family members were also clinically unaffected. Methods: FV procoagulant activity level was measured in the patient with an MDA-180 automated coagulation analyser (Trinity Biotech, Ireland). The patient’s peripheral blood leukocytes were separated by density centrifugation and fixed in methanol:glacial acetic acid (2:1). We then performed interphase fluorescent in-situ (FISH) analysis using probes covering the FV gene and the more telomeric HPC1 gene as a control. Genomic DNA was also isolated from the patient, and the coding region (25 exons) of the FV gene amplified by polymerase chain reaction (PCR) and sequenced. Results: FV activity assays revealed a severely reduced level of 9% (normal range: 60–130%). Factor V activity levels in the patient’s family members were not assessed. Peripheral blood karyotyping revealed an interstitial deletion of 1q: 46,XX,del(1)(q24.2q25.3 or q23.3q25.1). Interphase FISH analysis was performed. Red signals corresponded to the FV probe and green signals corresponded to HPC1, which is approximately 13 MB telomeric to FV. In contrast to healthy controls, the patient had a signal pattern of only 1 green HPC1 signal and 1 red FV signal, corresponding to heterozygous loss of the FV gene and adjacent chromosomal material. Sequencing of the retained allele revealed a novel hemizygous S234W mutation (encoded by exon 6). The lost serine is part of a conserved “SGP” peptide segment predicted to be a solvent-exposed region of the heavy chain of the FV protein. Conclusion: Most mutations causing FV deficiency are autosomal recessive and introduce frame shifts resulting in the generation of a premature termination codon. Karyotypic and FISH analysis of this patient revealed a novel mechanism for FV deficiency: loss of an entire FV allele as part of a chromosomal deletion, coupled with a point mutation in the other allele. Structural modeling of the consequences of the S234W point mutation, which is predicted to alter the hydrophobicity of the protein, is ongoing. Syndromes involving an interstitial deletion of 1q have been described in association with ATIII deficiency (Pallotta, Dalpra et al. 2001), but to our knowledge, this is the first description of a 1q deletion with FV deficiency.

Outcomes of external beam radiotherapy (EBRT) in advanced medullary thyroid carcinoma (MTC) are largely unknown. Retrospective review of data from patients with MTC, diagnosed from June 1, 1970, through December 31, 2007. Overall survival and locoregional tumor control rates were calculated. Seventeen patients had adjuvant or palliative EBRT delivered to 41 sites. Six patients initially had adjuvant EBRT (median, 60.80 Gy); none had relapse in the treated area. Five patients with locoregional recurrence after surgery were treated (median, 59.40 Gy), and durable disease control was achieved in 3. Twelve patients received palliative EBRT to 29 sites of metastatic disease (median, 30.00 Gy), which provided sustained symptom relief at 45% of sites. Five- and ten-year overall survival rates were 44% and 19%, respectively. Adjuvant EBRT may be most effective for prevention of locoregional recurrence. EBRT may provide sustained control of advanced, metastatic disease in select patients.