Antiphospholipid antibody syndrome and posttransplant renal thrombosis

Recommendations of the Spanish Rheumatology Society for Primary Antiphospholipid Syndrome. Part II: Obstetric Antiphospholipid Syndrome and Special Situations

OBJECTIVE

The difficulty in diagnosis and the spectrum of clinical manifestations that can determine the choice of treatment for antiphospholipid syndrome (APS) has fostered the development of recommendations by the Spanish Society of Rheumatology (SER), based on the best possible evidence. These recommendations can serve as a reference for rheumatologists and other specialists involved in the management of APS.

METHODS

A panel of 4rheumatologists, a gynaecologist and a haematologist with expertise in APS was created, previously selected by the SER through an open call or based on professional merits. The stages of the work were: identification of the key areas for the document elaboration, analysis and synthesis of the scientific evidence (using the Scottish Intercollegiate Guidelines Network, SIGN levels of evidence) and formulation of recommendations based on this evidence and formal assessment or reasoned judgement techniques (consensus techniques).

RESULTS

Forty-six recommendations were drawn up, addressing 5main areas: diagnosis and evaluation, measurement of primary thromboprophylaxis, treatment for APS or secondary thromboprophylaxis, treatment for obstetric APS and special situations. These recommendations also include the role of novel oral anticoagulants, the problem of recurrences or the key risk factors identified in these subjects. This document reflects the last 25, referring to the areas of: obstetric APS and special situations. The document provides a table of recommendations and treatment algorithms.

CONCLUSIONS

Update of SER recommendations on APS is presented. This document corresponds to part II, related to obstetric SAF and special situations. These recommendations are considered tools for decision-making for clinicians, taking into consideration both the decision of the physician experienced in APS and the patient. A part I has also been prepared, which addresses aspects related to diagnosis, evaluation and treatment.

Antiphospholipid syndrome, antiphospholipid antibodies and solid organ transplantation

Antiphospholipid syndrome is considered a high risk factor for any kind of surgery. Considering that all solid organ transplants are critically dependent on the patency of vascular anastomosis, there is much concern about the consequences this pro-thrombotic condition may have on transplantation. Relatively little information is available in the literature assessing the real risk that antiphospholipid syndrome or the presence of antiphospholipid antibodies represent in solid organ transplantation. The aim of this article is to review the literature related to transplantation of solid organs in patients diagnosed with antiphospholipid syndrome or patients with positive antiphospholipid antibodies.

Antiphospholipid syndrome in renal transplantation

Antiphospholipid syndrome (APS) may occur in isolation or in association with systemic lupus erythematosus (SLE), with the potential to cause renal failure via several distinct pathologies. Renal transplantation in the presence of APS carries a risk of early graft loss from arterial or venous thrombosis, or thrombotic microangiopathy (TMA). Whilst perioperative anticoagulation reduces the risk of large vessel thrombosis, it may result in significant haemorrhage, and its efficacy in preventing post-transplant TMA is uncertain. Here, we report a patient with end-stage kidney disease (ESKD) due to lupus nephritis and APS, in whom allograft TMA developed soon after transplantation despite partial anticoagulation. TMA resolved with plasma exchange-based therapy albeit with some irreversible graft damage and renal impairment. We discuss the differential diagnosis of post-transplant TMA, and current treatment options.

Management of end-stage renal disease patients with antiphospholipid antibody syndrome

AIMS

End-stage renal disease (ESRD) patients with antiphospholipid antibody syndrome (APAS) remain at high risk for the development of posttransplant renal thrombosis without the benefit of anticoagulation therapy. This study describes the clinical management of these high-risk patients on anticoagulation therapy.

METHODS

In this study period, 802 patients awaiting renal transplantation were screened for APAS. Twenty-seven of these patients (3%) had APAS. Of these 27, nine patients received cadaveric kidney transplants along with 409 patients who did not have APAS. Of the nine patients, seven were treated with coumadin and the remaining two were treated with heparin.

RESULTS

Of the seven patients treated with coumadin, five did not have thrombotic complications posttransplant. However, three of these patients were taken off coumadin due to bleeding complications at 6 months to 1 year posttransplant. They all returned to dialysis shortly thereafter. The remaining two patients have maintained their allografts on coumadin therapy for 3 and 5 years posttransplants. The other two patients had posttransplant renal thrombosis within 24 hours of their transplant despite coumadin therapy. Of the two patients treated with heparin, one is doing well at 6 years posttransplant while the other had early allograft loss due to thrombosis.

CONCLUSIONS

ESRD patients with APAS may benefit from anticoagulation therapy; however, early allograft loss and bleeding complication are two serious side effects of this therapy.

Efficacy of anticoagulation therapy in end-stage renal disease patients with antiphospholipid antibody syndrome

BACKGROUND

End-stage renal disease (ESRD) patients with antiphospholipid antibody syndrome (APAS) remain at high risk for the development of renal thrombosis without the benefit of anticoagulation therapy. This study examines the efficacy of anticoagulation therapy in this high-risk patient population.

METHOD

Of nine APAS renal-transplant patients, seven were treated with coumadin, whereas two were treated with heparin.

RESULTS

Of the two patients treated with heparin, one had early allograft loss, whereas the other patient is doing fine at 5 years posttransplant. Of the seven 7 patients treated with coumadin, two patients are doing well at 2 and 3 years posttransplant, two had early allograft loss, the remaining three patients returned to dialysis after they were taken off of the coumadin at 6, 12, and 20 months posttransplant because of bleeding complications.

CONCLUSIONS

Anticoagulation therapy is beneficial to some but not all APAS patients. In addition, bleeding complications are a serious side effect of this therapy.

Prothrombotic disorders in uremic type-1 diabetics undergoing simultaneous pancreas and kidney transplantation

BACKGROUND

Although prothrombotic disorders (PTD) are known to increase the risk of graft failure in kidney transplantation only, there are no data on PTD in simultaneous pancreas and kidney transplantation (SPK).

METHODS

Forty-seven SPK performed between September 2000 and July 2002 underwent routine screening for PTD. Data were retrospectively analyzed in view of complications (relaparotomy, graft thrombosis, pancreatitis, rejection) and graft function (HbA1c, serum creatinine) 3 months posttransplantation.

RESULTS

Twenty-five of forty-seven (53.2%) patients had 30 PTDs. Homozygous mutations of the MTHFR gene (C677T) were found in six, factor-V Leiden mutation (homo- or heterozygous G1691A) in seven, and prothrombin mutation (20210A) in one patient (group 1). Group 2 consists of deficiencies of protein C (n=1), of protein S (n=12), of antithrombin (n=1), and antiphospholipid syndromes (n=2). Overall, PTD had no influence on graft thrombosis (P=0.36) or rejection (P=0.56). In patients with homozygous mutations, relaparotomies were more often necessary than in patients without mutations (42.9% vs. 11.8%, P=0.046). In group 1, there was a trend toward a higher incidence of graft pancreatitis than in patients without mutations (38.5% vs. 14.7%, P=0.075). Three months posttransplantation, HbA1c was 6.0% in patients with and 5.5% in patients without PTD (P=0.023). With regard to serum creatinine, no significant differences were observed.

CONCLUSION

PTD are frequent in type-1 diabetics receiving SPK and may have a role in relaparotomies, graft pancreatitis, and pancreas graft function.

Antiphospholipid antibodies: discovery, definitions, detection and disease

Antiphospholipid antibodies (aPL) are immunoglobulins of IgG, IgM and IgA isotypes that target phospholipid (PL) and/or PL-binding plasma proteins. Detection of aPL in the laboratory is done currently by both immunoassays and functional coagulation tests. Convention defines aPL specificity in immunoassays according to the particular PL substrate present, for example aPS represents antiphosphatidylserine antibodies. This may be technically incorrect inasmuch as a particular PL may be responsible for binding and highly concentrating a specific plasma protein, the latter then becomes the target for the aPL. The binding of beta(2)GP-I (apolipoprotein H) to the negatively charged PL, cardiolipin (CL) provides a good example of this circumstance. In contrast, aPL which specifically prolong coagulation times in in vitro are called lupus anticoagulants (LA). The precise PL target(s) of the aPL responsible for LA activities are unknown and often debated. The persistent finding of aPL in patients in association with abnormal blood clotting and a myriad of neurological, obstetrical and rheumatic disorders often compounded by autoimmune diseases has led to an established clinical diagnosis termed antiphospholipid syndrome (APS). The common denominator for these APS patients is the presence of circulating aPL on two or more occasions and the observation of events attributable to abnormal or accelerated blood clotting somewhere in vivo. The purpose of this review is to collect, collate, and consolidate information concerning aPL.

Simultaneous pancreas-kidney transplantation in patients with antiphospholipid syndrome

BACKGROUND

Graft thrombosis is one of the main reasons of graft loss following simultaneous pancreas-kidney transplantation (SPK). Although antiphospholipid syndrome (APLS) is known as a high risk for graft thrombosis in kidney transplants alone, little is known about APLS in SPK.

METHODS

Between September 2000 and December 2001, 45 SPK were performed. The treatment and clinical course of 2 patients with APLS is presented.

RESULTS

In one patient, APLS was known before transplantation. After SPK, she was treated by systemic heparin followed by coumarin. Both grafts are doing well 5 months posttransplant. The second patient underwent SPK without knowledge of APLS. The patient developed a deep vein thrombosis 5 weeks posttransplant. Hypercoagulability screening revealed APLS. Treatment consisted of systemic anticoagulation. Grafts were not affected.

CONCLUSION

SPK can successfully be performed in APLS patients if anticoagulation is performed consistently. To reduce the risk of graft thrombosis, a pretransplant screening for APLS would probably be of benefit.

Role of anti-beta 2 glycoprotein 1 antibodies in ESRD patients with antiphospholipid antibody syndrome

INTRODUCTION

End stage renal disorder (ESRD) patients with antiphospholipid antibody syndrome (APAS) are at high risk for the development of post-transplant renal thrombosis. Positive titre of anticardiolipin antibodies (ACA) is considered a major characteristic of APAS. However, several studies have suggested that ACA in patients with APAS do not bind to phospholipids alone. Beta 2 glycoprotein 1 (beta 2gp1), a 40-kD plasma protein is required. In this study, we have tested a hypothesis that significant portions of our ESRD patients with APAS have antibodies only to beta 2gp1.

METHODS

Serum samples from each of 169 ESRD patients waiting for cadaver renal transplant in August 2000 were tested for ACA and anti-beta 2gp1 antibodies by enzyme-linked immunoabsorbent assay (ELISA) method. Twenty-four of these patients had clotting disorders that met the criteria established by the Eighth International Symposium on Antiphospholipid Antibodies. They included frequent arterio-venous (a-v) shunt thrombosis, cerebrovascular thrombosis, lupus, frequent abortions and microrenal angiopathy.

RESULTS

Thirty-three of the patients (20%) had positive titre of either ACA or beta 2gp1 or both. Twenty-eight patients had ACA antibodies, of which eight had no evidence of clotting disorder while remaining 20 patients had various clotting disorders. Fourteen of these 20 patients with APAS had the positive titre of ACA only; the remaining six patients had both the antibodies, i.e. anti-beta 2gp1 as well as ACA. There were four patients with APAS that had positive titres of only beta 2gp1 antibodies. In total there were 11 patients with beta 2gp1 antibodies, 10 of which had APAS, the remaining one did not. The sensitivity and the specificity of ACA test were 83 and 94%, respectively, and the sensitivity and specificity of beta 2gp1 antibody test were 71 and 99%, respectively. The chi-square analysis demonstrated that there was statistically significant correlation between positive titres of both the antibodies and the presence of APAS.

CONCLUSION

The APAS in the ESRD patients should be characterized by not only the positive titre of ACA but also the positive titres of anti-beta 2gp1 antibodies in association with history of clotting disorder.

Antiphospholipid antibodies. Risk assessments for solid organ, bone marrow, and tissue transplantation

The literature pertaining to transplantation of solid organs, bone marrow, and other tissues in aPL-positive patients has been reviewed. The effects that aPL have relative to BMT are altogether different than those ascribed to solid organs and tissues. By definition, the transplantation of allogeneic bone marrow serves to reconstitute the recipient with a completely new and genetically different repertoire of antibody-producing cells. Previously aPL-positive bone marrow recipients become aPL-negative subsequent to transplantation assuming that the marrow donor is aPL-negative. These observations are the basis for contemporary experimental approaches to curing certain autoimmune diseases with BMT. Similarly, it would follow that an aPL-negative patient provided cells from an aPL-positive donor could become aPL-positive and suffer increased risk for thrombosis. From the data provided in most of the non-bone marrow publications, the presence of aPL should be considered a grave risk factor for any potential solid organ or tissue transplant candidate. Peritoneal dialysis patients seem to be at maximal risk. Given the serious emotional and economic impact of irreversible thrombotic loss suffered by organ transplant recipients, these factors alone should justify the modest expense of pretransplant aPL screening. In the United States, the average cost of losing a kidney transplant to aPL-associated thrombosis was estimated from 1996 data to be $82,000. The cost of losing a heart or liver is measured not only in dollars but often in the patient's life. The encouraging news, however, is that once aPL are identified before transplantation, prophylactic anticoagulation seems to be capable of forestalling untoward aPL-associated allograft events. Clearly, much remains to be discovered in exploring the pathobiologic characteristics of aPL in the laboratory as well as in neutralizing their procoagulant effects at the bedside.