JAK2 V617F Mutation in Patients With Catastrophic Intra-abdominal ...

2 downloads 0 Views 179KB Size Report
patients with splanchnic vein thrombosis4 and in up to 80% of patients with hepatic vein thrombosis ... uted to congestion caused by portal hypertension.

Coagulation and Transfusion Medicine / JAK2 V617F IN ABDOMINAL THROMBOSIS

JAK2 V617F Mutation in Patients With Catastrophic Intra-abdominal Thromboses Christine McMahon, MD,1,2 Kareem Abu-Elmagd, MD, PhD,3 Franklin A. Bontempo, MD,4 Jeffrey A. Kant, MD, PhD,2* and Steven H. Swerdlow, MD1* Key Words: JAK2; Chronic myeloproliferative disorder; Thrombosis DOI: 10.1309/JA1WD8JNVLGYNQYE

Abstract Catastrophic intra-abdominal thrombosis can result from a variety of prothrombotic states, including polycythemia vera and essential thrombocythemia, both of which are frequently associated with an acquired mutation (V617F) in the JAK2 gene. To assess the prevalence and clinical implications of this mutation in the setting of intra-abdominal thrombosis, JAK2 V617F genotyping was performed in 42 patients who had catastrophic intra-abdominal thromboses resulting in visceral transplants. The prevalence of V617F was compared with that of other prothrombotic states for which molecular testing is routinely performed. V617F mutations were detected in 7 patients (17%), who were not distinguishable on the basis of their peripheral blood cell counts. The median posttransplantation survival of V617F+ patients was 17.5 months, compared with 116.4 months for the V617F– patients (ratio, 6.6; 95% confidence interval, 6.3-7.0). These results highlight the diagnostic usefulness of JAK2 V617F testing in this setting and underscore the clinical significance of a positive result.

736 736

Am J Clin Pathol 2007;127:736-743 DOI: 10.1309/JA1WD8JNVLGYNQYE

Chronic myeloproliferative disorders (CMPDs) and a number of other prothrombotic states confer an increased risk of visceral vascular thrombosis.1-3 Polycythemia vera (PV) or essential thrombocythemia (ET) has been reported in 25% to 65% of patients with splanchnic vein thrombosis4 and in up to 80% of patients with hepatic vein thrombosis (Budd-Chiari syndrome).5,6 The clinical diagnosis of CMPD in the setting of intraabdominal thrombosis can be obscured by the fact that hemoglobin levels, hematocrit values, leukocyte counts, and platelet counts may be only modestly elevated, within the normal range, or even decreased,4,6-11 and erythropoietin levels may be normal or elevated.12 Splenomegaly may not be present or may be attributed to congestion caused by portal hypertension. A recently described somatic mutation in the gene encoding a growth factor receptor–associated tyrosine kinase, JAK2, is present in myeloid cells of the majority of patients with PV and approximately one third of patients with ET or chronic idiopathic myelofibrosis.13-19 This mutation results in the substitution of phenylalanine for an evolutionarily conserved valine residue (V617F) in the auto-inhibitory domain of JAK2 and thereby renders the kinase active even in the absence of growth factors. Given the notorious difficulty sometimes encountered in recognizing CMPDs in patients with intra-abdominal thromboses, molecular testing for the JAK2 V617F mutation may be of particular interest in this setting. Visceral vascular thrombosis is a common cause of native intestinal loss in patients who are referred for intestinal transplants.20 We, therefore, studied the prevalence of the JAK2 V617F mutation in patients who had intra-abdominal thromboses that resulted in the need for small intestinal or multivisceral transplantation, the majority of whom did not have a clinically recognized CMPD. The © American Society for Clinical Pathology

Coagulation and Transfusion Medicine / ORIGINAL ARTICLE

incidence was compared with that of other prothrombotic risk factors in these patients, and the clinical implications of finding the JAK2 V617F mutation were evaluated.

analysis was performed by using the Kaplan-Meier method. Statistical analyses were performed using Prism 3.0 (GraphPad Software, San Diego, CA) and SPSS version 13 (SPSS, Chicago, IL).

Materials and Methods Results Study Design Of 182 small intestinal or multivisceral transplants performed in adults at the University of Pittsburgh Medical Center (UPMC; Pittsburgh, PA) between 1990 and 2005, 67 were necessitated by catastrophic intra-abdominal thromboses. In a retrospective study approved by the internal review board of the University of Pittsburgh, we identified a set of 42 of the patients for whom DNA samples were available for analysis. The DNA had been isolated using the Purgene kit (Gentra Systems, Minneapolis, MN) from peripheral blood samples originally obtained as part of the patient’s hypercoagulability workup. The samples were tested for the JAK2 V617F mutation by allele-specific polymerase chain reaction (PCR) by using the method described by Baxter et al.13 Genetic testing for the factor V Leiden and prothrombin 20210 G>A mutations was performed on all specimens by using the Invader platform (Third Wave Technologies, Madison, WI). Thirty additional DNA samples left over from unrelated genetic testing for mutations in the PRSS1 gene (associated with hereditary pancreatitis) served as negative control samples for the JAK2 V617F allele-specific PCR assay. Clinical records were reviewed without knowledge of the patient’s JAK2 V617F status, and the following clinical data were abstracted: CBC counts (at time of admission to UPMC and peak follow-up values), all available results of coagulation laboratory workups, site(s) of thromboses, type of transplant, clinically identified cause of thrombosis, comorbid conditions, causes of posttransplantation mortality, and status at and duration of time to most recent follow-up. Data for the following prothrombotic risk factors were available as follows: protein S levels, 36 patients; protein C levels, 37 patients; antithrombin levels, 36 patients; and lupus anticoagulant studies, 40 patients. Because interpretation of some of these studies would be complicated by warfarin therapy or hepatic insufficiency often present in our patient cohort and because many of the patients received much of their medical care at outside institutions, only the clearly positive diagnostic findings are tabulated in the “Results” section. Statistical Analysis Correlations between clinical variables and JAK2 V617F mutation status were tested for significance by using the Fisher exact test for categorical variables and the MannWhitney rank sum test for continuous variables. Survival

The JAK2 V617F mutation was present in 7 of 42 DNA samples from patients with intra-abdominal thrombosis (17%) but in none of the negative control samples. All 3 patients who had previously recognized or suspected CMPD had the mutation ❚Table 1❚. Neither the initial nor the peak peripheral blood cell counts and hemoglobin levels showed significant differences between the JAK2 V617F+ and JAK2 V617F– patients, and average platelet counts for both groups fell within the normal range ❚Figure 1A❚, ❚Figure 1B❚, ❚Figure 1C❚, ❚Table 2❚, and ❚Table 3❚. However, the 2 highest peak platelet counts were found in V617F+ patients, whose platelet counts rose to more than 1.5 million per microliter approximately 2 weeks following splenectomy. Of the 42 patients, 6 (14%) were heterozygous for the factor V Leiden mutation. One patient was heterozygous for prothrombin 20210 G>A. None of the 7 patients identified as having mutations in clotting factor genes had the JAK2 V617F mutation. Definite evidence for a lupus anticoagulant was found in 7 of 40 patients for whom test results were available, with approximately equal frequency in patients with and without the JAK2 V617F mutation. Nonhematologic conditions that could have contributed to thrombosis were present in 13 patients, including liver disease (10), acute pancreatitis (3), cardiogenic emboli (2), and metastatic colon cancer (1) ❚Table 4❚. There were no statistically significant patterns of association between the V617F mutation and prothrombotic risk factors other than the fact all 3 patients with known or suspected CMPD were positive for the mutation (Table 1). There were no statistically significant differences between patients with and without JAK2 V617F mutations in age, presence of comorbid conditions such as hypertension or diabetes, or the precise type of transplant the patient received (isolated small bowel vs multivisceral; Table 1). The only statistically significant association between JAK2 V617F status and site of thrombosis occurred because the 2 patients with hepatic vein thrombosis (Budd-Chiari syndrome) both had the V617F mutation (P = .02; Fisher exact test). The median posttransplantation survival of JAK2 V617F+ patients was 17.5 months, compared with 116.4 months for patients without the mutation (ratio, 6.6; 95% confidence interval, 6.3-7.0). The shorter survival of JAK2 V617F+ patients following transplantation was statistically significant ❚Figure 1D❚. Of 7 patients with the V617F mutation, 6 died Am J Clin Pathol 2007;127:736-743

© American Society for Clinical Pathology 737

DOI: 10.1309/JA1WD8JNVLGYNQYE

737 737

McMahon et al / JAK2 V617F IN ABDOMINAL THROMBOSIS

❚Table 1❚ Demographic Characteristics, Prothrombotic Risk Factors, and Surgical Intervention Analyzed by Presence or Absence of the JAK2 V617F Mutation*

Patients (n = 42) Mean age, y (range) Male/female Risk factors for hypercoagulability CMPD diagnosed or suspected Factor V Leiden Prothrombin 20210 G>A Lupus anticoagulant Antecedent contributing factors Liver disease Pancreatitis Metastatic cancer Diabetes Hypertension History of smoking Site(s) of thrombosis Superior mesenteric artery Superior mesenteric vein Portal vein Hepatic vein Surgical procedure Isolated small bowel transplant Multivisceral transplant Splenectomy

JAK2 WT

JAK2 V617F

P†

35 (83) 44.4 (24.5-61.2) 18:17 (M, 51%)

7 (17) 46.5 (18-7-64.7) 1:6 (M, 14%)

.46 .10

0 (0) 6 (17) 1 (3) 6 (17)

3 (43) 0 (0) 0 (0) 1 (14)

.00 .57 1.00 1.00

10 (29) 4 (11) 1 (3) 5 (14) 5 (14) 10 (29)

0 (0) 0 (0) 0 (0) 1 (14) 1 (14) 0 (0)

.17 1.00 1.00 1.00 1.00 .17

18 (51) 14 (40) 14 (40) 0 (0)

2 (29) 4 (57) 3 (43) 2 (29)

.41 .44 1.00 .02

9 (26) 26 (74) 23 (66)

4 (57) 3 (43) 3 (43)

.18 .18 .40

CMPD, chronic myeloproliferative disorder; WT, wild-type (nonmutated). * Data are given as number (percentage) unless otherwise indicated. † P values were calculated by using the Fisher exact test for categorical variables and the Mann-Whitney rank sum test for patient age.

within 36 months after transplantation. Causes of death of the 6 patients with V617F mutations included an aggressive posttransplant lymphoproliferative disorder, sepsis secondary to bone marrow failure, allograft-liver failure, and 3 cases of sepsis preceded by mental status changes ❚Table 5❚. Whether the latter findings are related to microvascular ischemic changes is unknown.

Discussion In a cohort of patients who received small bowel or multivisceral transplants following catastrophic intra-abdominal thromboses, we found the JAK2 V617F mutation to have a prevalence of 17%, which is comparable to that of factor V Leiden in this patient group and much higher than the prevalence of the prothrombin 20210 G>A mutation. Whereas heterozygosity for the factor V Leiden mutation is found in 4.3% of the general population21 and the prothrombin 20210 G>A mutation is found in 1% to 2%,22 the JAK2 V617F mutation has not been detected in more than 558 healthy subjects or 48 patients with reactive erythrocytosis using techniques that have sensitivities comparable to the allele-specific PCR method used in the present study, which is sufficient to detect the mutation in populations with 1% to 10% mutated cells.13-18,23 738 738

Am J Clin Pathol 2007;127:736-743 DOI: 10.1309/JA1WD8JNVLGYNQYE

In addition, the JAK2 V617F mutation was not identified in our 30 control samples. One group recently reported detection of the JAK2 V617F mutation in peripheral blood samples from 10% of 57 healthy donors, using a very sensitive quantitative PCR approach,24 which allows detection of JAK2 V617F alleles at proportions as low as 0.01%.25 However, the JAK2 V617F mutation detected by using techniques as described in this report is a significant abnormality strongly associated with a clinically consequential hematologic disorder. In our series, 2 patients had been diagnosed with PV before their thrombotic events and a third patient had a subsequent bone marrow biopsy that suggested ET. JAK2 testing identified 4 additional patients in our cohort (10%) who did not have a previously known or suspected CMPD and who did not meet criteria for a diagnosis of PV or ET based on their peripheral blood cell counts at the time of their arrival at our institution. Patients with ET or PV exhibiting normal or low peripheral blood cell counts is a well-documented phenomenon.4,6-11 Because patients who had been completely asymptomatic before their thrombotic events may not have had peripheral blood evaluations, it cannot be excluded that platelet, neutrophil, or RBC counts were elevated when the thromboses occurred. It is also possible that even with normal peripheral blood cell counts, patients with CMPD are at risk © American Society for Clinical Pathology

Coagulation and Transfusion Medicine / ORIGINAL ARTICLE

A

B 2,500 20 2,000

16

Platelets (x 109/L)

Hemoglobin (g/dL)

18 14 12 10 8 6

1,500 1,000 500

4 2

0

0 WT

V617F Initial

WT

V617F

WT

Maximum

V617F Initial

WT

V617F Maximum

D

C 80

1.0

70

WBCs (x 109/L)

60

0.8

50 0.6 WT

40 0.4

30 20

V617F

0.2

10 0.0 0 WT

V617F Initial

WT

V617F

0.0

50.0

Maximum

100.0

150.0

200.0

Months

❚Figure 1❚ Peripheral blood cell counts and posttransplantation survival in patients with nonmutated and V617F-mutated JAK2 genes. Comparison of hemoglobin levels (A), platelet counts (B), and WBC counts (C) at admission to this institution (initial) and maximum values recorded. No statistically significant differences between median values for the groups were found (rank sum tests). D, Posttransplantation survival in patients with nonmutated/wild-type (WT) JAK2 genes was significantly longer than in patients with V617F-mutated JAK2 genes (Kaplan-Meier plot, P = .0001; log-rank test).

for thrombosis owing to qualitative changes in their platelets or neutrophils. Increased expression of activation markers on platelets and neutrophils, as well as increased formation of platelet-neutrophil aggregates, as seen in patients with ET and PV,26-29 may be at least partly responsible for the increased risk of thrombosis.30,31 The presence of what has been described as latent, occult, or a forme fruste variant of CMPD has been identified based

on bone marrow biopsy findings or endogenous erythroid colony formation in a significant number of patients with normal peripheral blood cell counts who had portal or hepatic vein thromboses.4,6,9,32 Furthermore, Patel et al11 found the JAK2 V617F mutation in 24 of 41 patients with Budd-Chiari syndrome, including 6 who had nondiagnostic bone marrow biopsies and negative endogenous erythroid colony results and did not meet criteria for diagnosis of a CMPD. Thus, in Am J Clin Pathol 2007;127:736-743

© American Society for Clinical Pathology 739

DOI: 10.1309/JA1WD8JNVLGYNQYE

739 739

McMahon et al / JAK2 V617F IN ABDOMINAL THROMBOSIS

❚Table 2❚ Survival Times and Peripheral Blood Cell Counts* Platelet Count (× 109/L) Case No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 *

Hemoglobin (g/dL)

WBC Count (× 109/L)

Hematocrit (%)

Survival (d)

Initial

Peak

Initial

Peak

Initial

Peak

Initial

Peak

37 375 518 525 645 742+ 1,077 0 62 121 229+ 248+ 229 310+ 355+ 374+ 540+ 597+ 606+ 701+ 732+ 778+ 779+ 771 928+ 931+ 993+ 1,168+ 1,175+ 1,414+ 1,693+ 1,703+ 1,825+ 1,885+ 2,006+ 2,047+ 2,540+ 2,711+ 2,809+ 3,383+ 3,492 5,697+

392 270 147 342 451 369 162 373 426 54 26 260 163 310 482 68 231 107 518 127 405 183 95 129 253 153 313 48 591 429 308 412 268 416 83 239 237 112 242 92 94 251

458 1,097 230 2,367 1,778 654 258 812 629 199 448 338 406 602 494 553 433 628 639 815 671 303 862 617 661 908 455 613 603 1,182 676 662 634 416 267 481 497 247 560 520 780 605

12.2 12.5 12.1 9.5 13.9 12.6 9.4 14.5 13.8 7.7 9.2 11.8 12.2 15 10.4 12.5 10.9 11.1 8.4 13.3 10.8 11.4 9.2 13.2 9.4 17.3 9.2 13.8 12.1 8.5 11 10 12.3 11.2 10.2 17.5 10.6 15.2 11.6 12.9 11.4 9.1

12.2 14.3 14.2 14.1 13.9 13.3 12.5 17.3 14.4 11.7 12.8 15.5 14.2 15 14.5 12.8 12.8 15.5 13.2 13.6 13.1 16.4 15 14.1 12.6 17.7 14.2 15.4 14.9 12.4 12.6 15.1 13 14.4 13.9 18.3 12.3 15.2 14.2 15.5 15.5 14.7

39.1 37.2 37 27.8 40.8 37.4 29.3 43.1 40.9 23.6 26.7 35 35.2 43.7 30.8 36.6 31.7 33.3 25 38.5 32.3 33.3 28.3 39.6 28.9 49.3 26 40.2 34.8 26.6 32.7 30.3 35.8 31.5 29.6 50.4 32.9 45 33.5 37.6 33.3 27

39.1 39.9 46.5 42 40.8 38.4 37.6 52.2 43.5 33.7 38.5 47.6 42.1 43.7 43.4 39 38.3 43.6 39 39.3 41.8 47.7 44 41.7 38.4 50.7 43.7 45.8 43.1 38.3 38.2 44.8 37.6 42.2 41.5 53.5 37.3 45 41.8 47.2 45.9 43.3

18.2 13.1 5.2 6.3 5.4 9.5 3.2 11.1 11.3 2.4 1.5 6.3 4.7 18 10.6 4.9 3.9 4.6 15.1 6.3 11 4.4 1.7 5.9 6.4 7.5 9.9 10.2 11.1 21.5 9.2 7.2 7.1 4.5 9.9 10.3 7.4 6.1 3.7 4 12.3 7.3

28.8 41.6 16.9 67.5 41.3 15.4 27.1 58.8 36.7 29 15.9 22 29.8 41 44.7 35.6 5.4 25.7 15.1 38.3 39.4 17 49.9 46.9 28.2 26.9 32.2 36.2 37.7 23.3 25.2 21.7 26.9 11.3 30.2 19.4 19.2 30 13.2 36.1 38.2 23.5

Cases 1-7 are JAK2 V617F+. Values for platelets and WBCs are given in Système International (SI) units; conversions to conventional units are as follows: platelets (× 103/µL), divide by 1.0; WBC count (/µL), divide by 0.001; values for hemoglobin and hematocrit are given in conventional units; conversions to SI units are as follows: hemoglobin (g/L), multiply by 10.0; hematocrit (proportion of 1.0), multiply by 0.01.

❚Table 3❚ Peripheral Blood Cell Count Values According to JAK2 V617F Status* Platelet Count (× 109/L)

Mean V617F WT Median V617F WT

Hemoglobin (g/dL)

Hematocrit (%)

WBC Count (× 109/L)

Initial

Peak

Initial

Peak

Initial

Peak

Initial

Peak

305 243

977 578

11.7 11.7

13.5 14.4

35.5 34.4

40.6 42.8

8.7 8.0

34.1 29.4

342 239

654 603

12.2 11.4

13.9 14.4

37.2 33.3

39.9 43.1

6.3 7.2

28.8 29.0

WT, wild-type (nonmutated). * Values for platelets and WBCs are given in Système International (SI) units; conversions to conventional units are as follows: platelets (× 103/µL), divide by 1.0; WBC count (/µL), divide by 0.001; values for hemoglobin and hematocrit are given in conventional units; conversions to SI units are as follows: hemoglobin (g/L), multiply by 10.0; hematocrit (proportion of 1.0), multiply by 0.01.

740 740

Am J Clin Pathol 2007;127:736-743 DOI: 10.1309/JA1WD8JNVLGYNQYE

© American Society for Clinical Pathology

Coagulation and Transfusion Medicine / ORIGINAL ARTICLE

❚Table 4❚ Patient Characteristics, Vessels Involved by Thrombosis, and Clinical Impression of the Cause of the Prothrombotic State* Case No./Sex/Age at Transplantation (y) SMA 1/F/35 2/F/50 3/F/64 4/F/18 5/M/59 6/F/55 7/F/41 8/F/36 9/M/33 10/M/54 11/F/40 12/M/53 13/M/61 14/M/53 15/F/51 16/M/52 17/M/25 18/M/57 19/F/48 20/M/58 21/F/44 22/F/31 23/F/49 24/M/55 25/M/24 26/M/47 27/F/43 28/M/43 29/F/55 30/F/36 31/F/47 32/F/29 33/F/56 34/F/50 35/M/41 36/M/41 37/F/52 38/M/45 39/F/33 40/M/23 41/M/32 42/F/26

SMV

Portal Vein

Hepatic Vein

+

+

+ +

+

IMA

+ + + + + + + + + + + +

+

+ + + + + +

+ + + +

+ + + + + + + +

+ + + + +

+ +

+

+ + + + + + +

+ +

+

+ + + +

+

Clinical Explanation for Hypercoagulable State Polycythemia vera Polycythemia vera Lupus anticoagulant Essential thrombocythemia Unknown Unknown Unknown Factor V Leiden mutation; primary biliary cirrhosis Factor V Leiden mutation; pancreatitis Possible protein S deficiency, liver disease Aneurysm Lupus anticoagulant Metastatic colon cancer Unknown Possible heparin-induced thrombocytopenia Lupus anticoagulant; pancreatitis Platelet defect, glycoprotein 1A mutation Liver disease; diabetes; cardiogenic emboli Prothrombin mutation; surgery; trauma Liver disease Oral contraceptives; smoking; hypertension Lupus anticoagulant Liver cirrhosis Liver cirrhosis Unknown Liver disease (hepatitis C virus) Lupus anticoagulant Liver disease (hepatitis B and C viruses); pancreatitis; smoking; diabetes mellitus Multiple surgeries; smoking Possible platelet dysfunction Liver disease Unknown; factor VIII level elevated Unknown Factor V Leiden mutation Lupus anticoagulant Lupus anticoagulant Factor V Leiden mutation Liver cirrhosis Protein C deficiency; cardiogenic emboli Factor V Leiden mutation Factor V Leiden mutation Unknown

IMA, inferior mesenteric artery; SMA, superior mesenteric artery; SMV, superior mesenteric vein; +, involvement present. * Cases 1-7 have JAK2 V617F mutations.

❚Table 5❚ Causes of Posttransplantation Mortality Case No./Sex/ Age (y) 1/F/35 2/F/50 3/F/64 4/F/18 5/M/59 7/F/41 8/F/36 9/M/33 10/M/54 13/M/61 24/M/55 41/M/32

Survival (d)

JAK2 V617F

37 375 518 525 645 1,077 0 62 121 229 771 3,492

+ + + + + + – – – – – –

Clinically Identified Prothrombotic Risk Factor

Cause of Death Rectosigmoid thrombosis; sepsis Bone marrow failure; neutropenia; sepsis Cerebral vascular disease; terminal events unknown Posttransplant lymphoproliferative disorder Repeated thromboses; cerebral vascular disease; sepsis Allograft dysfunction; native liver failure Primary graft failure (liver); extensive thrombosis Aortic pseudoaneurysm Sepsis Chronic rejection; Nocardia infection Acute gastric perforation Mycotic aortoenteric fistula; massive stroke

Polycythemia vera Polycythemia vera Lupus anticoagulant Essential thrombocythemia Unknown Unknown Factor V Leiden; primary biliary cirrhosis Factor V Leiden; pancreatitis Possible protein S deficiency Metastatic colon cancer Liver cirrhosis Factor V Leiden

Am J Clin Pathol 2007;127:736-743

© American Society for Clinical Pathology 741

DOI: 10.1309/JA1WD8JNVLGYNQYE

741 741

McMahon et al / JAK2 V617F IN ABDOMINAL THROMBOSIS

patients with intra-abdominal thrombosis, the CMPD-associated JAK2 V617F mutation may occur even in the absence of any other evidence for a CMPD, highlighting the usefulness of this testing in the workup for a prothrombotic state. The incidence of recognized CMPD in our study population is low compared with some previously published series of patients with Budd-Chiari syndrome or other intra-abdominal thromboses. This may reflect a selection bias, if patients with CMPD are less likely to be referred for transplantation, or could result from some studies including only patients who had undergone bone marrow biopsies or excluding patients with liver cirrhosis and portal vein thrombosis.4,11,33 Furthermore, the strongest association between CMPD and intra-abdominal thrombosis is with hepatic vein thrombosis or the Budd-Chiari syndrome, and our patient population was more heterogeneous.3-6,9,33 In addition, although no patients lacking the JAK2 V617F mutation had clinically recognized CMPD, its absence does not exclude a CMPD because at least 43% of patients with ET13 and even 3% to 11% of patients with PV lack JAK2 V617F mutations.13,14 We found a striking pattern of shorter posttransplantation survival times in patients with the JAK2 V617F mutation. The causes of death in this patient group are heterogeneous, and a causal link to the JAK2 V617F mutation is not obvious. The retrospective nature of this study and the fact that many patients received much of their posttransplantation medical care at widely dispersed institutions preclude a complete analysis of factors that could have contributed to posttransplantation morbidity and mortality. Our results suggest that testing for the JAK2 V617F mutation should be included in the evaluation of patients with catastrophic intra-abdominal thromboses. The notably reduced survival of patients with the JAK2 V617F mutation who received intestinal transplants is a phenomenon that warrants confirmation in a prospective study and further investigation to understand the pathophysiology and optimal management of patients with JAK2 V617F–associated thrombotic disease. From the Department of Pathology, Divisions of 1Hematopathology and 2Molecular Diagnostics; 3Department of Surgery, Thomas E. Starzl Transplantation Institute; and 4Department of Internal Medicine, Division of Hematology, University of Pittsburgh School of Medicine, Pittsburgh, PA. Address reprint requests to Dr Swerdlow: Division of Hematopathology, University of Pittsburgh Medical Center, Presbyterian Hospital, Sixth Floor, Room C606, 200 Lothrup St, Pittsburgh, PA 15213. * These authors contributed equally. Acknowledgments: We thank Lillian Martin and Dottie Williams for their efforts as honest brokers for this study; Denise Bell for performing Invader assays on some of the samples, David McMahon, PhD, and Mark Fung, MD, PhD, for critically reading the manuscript, and the staff of the molecular diagnostics laboratory at UPMC for helpful discussions.

742 742

Am J Clin Pathol 2007;127:736-743 DOI: 10.1309/JA1WD8JNVLGYNQYE

References 1. Menon KVN, Shah V, Kamath P. The Budd-Chiari syndrome. N Engl J Med. 2004;350:578-585. 2. Kumar S, Sarr MG, Kamath P. Mesenteric venous thrombosis. N Engl J Med. 2001;345:1683-1688. 3. Briere J. Budd-Chiari syndrome and portal vein thrombosis associated with myeloproliferative disorders: diagnosis and management. Semin Thromb Hemost. 2006;32:208-218. 4. Chait Y, Condat B, Cazals-Hatem D, et al. Relevance of the criteria commonly used to diagnose myeloproliferative disorder in patients with splanchnic vein thrombosis. Br J Haematol. 2005;129:553-560. 5. Melear JM, Goldstein RM, Levy MF, et al. Hematologic aspects of liver transplantation for Budd-Chiari syndrome with special reference to myeloproliferative disorders. Transplantation. 2002;74:1090-1095. 6. Valla D, Casadevall N, Lacombe C, et al. Primary myeloproliferative disorder and hepatic vein thrombosis: a prospective study of erythroid colony formation in vitro in 20 patients with Budd-Chiari syndrome. Ann Intern Med. 1985;103:329-334. 7. Anger BR, Seifried E, Scheppach J, et al. Budd-Chiari syndrome and thrombosis of other abdominal vessels in the chronic myeloproliferative diseases. Klin Wochenschr. 1989;67:818-825. 8. Regev A, Stark P, Blickstein D, et al. Thrombotic complications of essential thrombocythemia with relatively low platelet counts. Am J Hematol. 1997;56:168-172. 9. De Stefano V, Teofili L, Leone G, et al. Spontaneous erythroid colony formation as the clue to an underlying myeloproliferative disorder in patients with Budd-Chiari syndrome or portal vein thrombosis. Semin Thromb Hemost. 1997;23:411-418. 10. McNamara C, Juneja S, Wolf M, et al. Portal or hepatic vein thrombosis as the first presentation of a myeloproliferative disorder in patients with normal peripheral blood counts. Clin Lab Haematol. 2002;24:239-242. 11. Patel RK, Lea NC, Heneghan MA, et al. Prevalence of the activating JAK2 tyrosine kinase mutation V617F in the BuddChiari syndrome. Gastroenterology. 2006;130:2031-2038. 12. Thurmes PJ, Steensma DP. Elevated serum erythropoietin levels in patients with Budd-Chiari syndrome secondary to polycythemia vera: clinical implications for the role of JAK2 mutation analysis. Eur J Haematol. 2006;77:57-60. 13. Baxter EJ, Scott LM, Campbell PJ, et al. Acquired mutation of the tyrosine kinase JAK2 in human myeloproliferative disorders. Lancet. 2005;365:1054-1061. 14. James C, Ugo V, Le Couedic JP, et al. A unique clonal JAK2 mutation leading to constitutive signalling causes polycythaemia vera. Nature. 2005;434:1144-1148. 15. Kralovics R, Passamonti F, Buser AS, et al. A gain-of-function mutation of JAK2 in myeloproliferative disorders. N Engl J Med. 2005;352:1779-1790. 16. Levine RL, Wadleigh M, Cools J, et al. Activating mutation in the tyrosine kinase JAK2 in polycythemia vera, essential thrombocythemia, and myeloid metaplasia with myelofibrosis. Cancer Cell. 2005;7:387-397. 17. Jones AV, Kreil S, Zoi K, et al. Widespread occurrence of the JAK2 V617F mutation in chronic myeloproliferative disorders. Blood. 2005;106:2162-2168. 18. Zhao R, Xing S, Li Z, et al. Identification of an acquired JAK2 mutation in polycythemia vera. J Biol Chem. 2005;280:2278822792.

© American Society for Clinical Pathology

Coagulation and Transfusion Medicine / ORIGINAL ARTICLE

19. Jelinek J, Oki Y, Gharibyan V, et al. JAK2 mutation 1849G>T is rare in acute leukemias but can be found in CMML, Philadelphia chromosome–negative CML, and megakaryocytic leukemia. Blood. 2005;106:3370-3373. 20. Giraldo M, Martin D, Colangelo J, et al. Intestinal transplantation for patients with short gut syndrome and hypercoagulable states. Transplant Proc. 2000;32:1223-1224. 21. Ridker PM, Miletich JP, Hennekens CH, et al. Ethnic distributions of factor V Leiden in 4047 men and women: implications for venous thromboembolism screening. JAMA. 1997;277:1305-1307. 22. Poort SR, Rosendaal FR, Reitsma PH, et al. A common genetic variation in the 3'-untranslated region of the prothrombin gene is associated with elevated plasma prothrombin levels and an increase in venous thrombosis. Blood. 1996;88:3698-3703. 23. Greiner TC. Diagnostic assays for the JAK2 V617F mutation in chronic myeloproliferative disorders. Am J Clin Pathol. 2006;125:651-653. 24. Sidon P, Heimann P, Lambert F, et al. Combined locked nucleic acid and molecular beacon technologies for sensitive detection of the JAK2V617F somatic single-base sequence variant. Clin Chem. 2006;52:1436-1438. 25. Sidon P, El Housni H, Dessars B, et al. The JAK2V617F mutation is detectable at very low level in peripheral blood of healthy donors [letter]. Leukemia. 2006;20:1622. 26. Falanga A, Marchetti M, Evangelista V, et al. Polymorphonuclear leukocyte activation and hemostasis in patients with essential thrombocythemia and polycythemia vera. Blood. 2000;96:4261-4266.

27. Falanga A, Marchetti M, Vignoli A, et al. Leukocyte-platelet interaction in patients with essential thrombocythemia and polycythemia vera. Exp Hematol. 2005;33:523-530. 28. Arellano-Rodrigo E, Alvarez-Larran A, Reverter JC, et al. Increased platelet and leukocyte activation as contributing mechanisms for thrombosis in essential thrombocythemia and correlation with the JAK2 mutational status. Haematologica. 2006;91:169-175. 29. Alvarez-Larran A, Garcia-Pagan JC, Abraldes JG, et al. Increased CD11b neutrophil expression in Budd-Chiari syndrome or portal vein thrombosis secondary to polycythemia vera. Br J Haematol. 2004;124:329-335. 30. Harrison CN. Platelets and thrombosis in myeloproliferative diseases. Hematology (Am Soc Hematol Educ Program). 2005:409-415. 31. Falanga A, Marchetti M, Barbui T, et al. Pathogenesis of thrombosis in essential thrombocythemia and polycythemia vera: the role of neutrophils. Semin Hematol. 2005;42:239-247. 32. Valla D, Casadevall N, Huisse MG, et al. Etiology of portal vein thrombosis in adults: a prospective evaluation of primary myeloproliferative disorders. Gastroenterology. 1988;94:10631069. 33. Denninger MH, Chait Y, Casadevall N, et al. Cause of portal or hepatic venous thrombosis in adults: the role of multiple concurrent factors. Hepatology. 2000;31:587-591.

Am J Clin Pathol 2007;127:736-743

© American Society for Clinical Pathology 743

DOI: 10.1309/JA1WD8JNVLGYNQYE

743 743

Suggest Documents