Lupus thrombocytopenia: pathogenesis and therapeutic implications

systemic lupus erythematosus, thrombocytopenia, mycophenolate mofetil, rituximab, thrombopoietin receptor agonists. Corresponding author: Anna Christoforidou Department of Hematology University Hospital of Alexandroupolis, Area of Dragana 68100, Alexandroupolis, Greece. Tel.: +30 2551351511 E-mail: [email protected]

Systemic Lupus Erythematosus (SLE) is frequently complicated by cytopenias. Thrombocytopenia is usually non severe and its frequency ranges from 20% to 40%. It is mostly an autoimmune process caused by autoantibodies against platelet surface glycoproteins and it is associated with worse prognosis in SLE. It can also be a result of SLE treatment with azathioprine, methotrexate and rarely hydroxychloroquine or thrombotic microangiopathy or macrophage activation syndrome. If thrombocytopenia is mild (>50x109/L) and there is no other evidence of disease there is no need of therapy. Severe thrombocytopenia is less frequent and needs therapeutic management. Corticosteroids are the cornerstone of therapy. Continuous high dose oral prednisolone or pulse high dose methylprednisolone (MP) with or without intravenous immune globulin are used in the acute phase. Second line agents (hydroxychloroquine, danazol, azathioprine, cyclosporine, mycophenolate mofetil, cyclophosphamide, rituximab) are usually needed. Splenectomy is indicated for recurrent or resistant cases. There are no evidence-based guidelines to facilitate selection of one drug over another but certainly the co-existence of other systemic SLE manifestations must be taken into account. Newer therapies are emerging although there is no consensus on the treatment of refractory lupus thrombocytopenia due to the absence of controlled randomized trials. Mediterr J Rheumatol 2017;28(1):20-6 https://doi.org/10.31138/mjr.28.1.20 Article Submitted 28/11/2016; Revised Form 01/03/2017; Accepted 14/03/2017 REVIEW Lupus thrombocytopenia: pathogenesis and therapeutic implications Nikolaos Galanopoulos, Anna Christoforidou, Zoe Bezirgiannidou 1Outpatient Department of Rheumatology, University General Hospital of Evros (Alexandroupolis), Thrace, Greece 2Department of Haematology, Democritus University of Thrace, Alexandroupolis, Greece 21 TITLE21 cytopenia may be due to the development of thrombotic microangiopathy,13,14 antiphospholipid syndrome or sple- nomegaly with hypersplenism. Macrophage activation syndrome should be suspected in patients with multiple cytopenias and fever with a rapid onset especially those with juvenile SLE.15 Thrombocytopenia in SLE is associated with a worse prognosis and higher mortality from the disease. 12,16,17 It has been linked with a severe disease course including neuropsychiatric disorders, renal involvement, hemolytic anemia and antiphospholipid syndrome.7,18 Most studies have shown an association between thrombocytopenia and mortality, however a few did not found such a rela - tionship.1,19 In two large studies thrombocytopenia was the only independent predictor for mortality in SLE. 16,20 The leading cause of death in the Reveille et al. 20 study was infection. It has been shown that it is not thrombocy- topenia itself that influences survival, but its coexistence with multiple organ damage and treatment related com- plications.12 A different presentation with a less severe, chronic form of thrombocytopenia, not related to disease activity is also common, and appears to be less respon- sive to corticosteroid therapy.1 SLE has a significant genetic predisposition.21 In a prom- inent study by Scofield RH et al., families with even one member with thrombocytopenic SLE seemed to be re - peatedly affected by a serious clinical phenotype that was assigned to a familial form of the disease, associated with genetic linkages at 1q22-23 and 11p13. 22 In these family pedigrees, even the non-thrombocytopenic SLE patients presented with multiple organ damage such as serositis, nephritis, neuropsychiatric disease, and hemo- lytic anemia. PATHOGENESIS Autoantibodies targeting antigenic glycoproteins on the platelet membrane are central to the destruction of plate- lets in SLE.23-25 In some cases other autoantibodies such as antiphospholipid antibodies 26,27 and autoantibodies against thrombopoietin (TPO) or TPO receptor (c-mpl) are identified. 28-30 Antibody-coated platelets are sub - sequently removed by splenic and other reticular mac - rophages, through binding on their surface Fc gamma receptor. Anti-IIb/IIIa antibodies, either circulating or platelet-bound (MAIPA method), are the most frequent finding, like in ITP , but similar to ITP they are not specific for thrombocyto - penia, as their detection ranges from 30-70% in throm - bocytopenic patients and in contrast many patients positive for these antibodies do not ever develop throm- bocytopenia.31,32 However, in previously antibody-pos - itive patients recovering from thrombocytopenia after immunosuppressive therapy, these antibodies disappear and reappear in relapses, thus indicating their pathoge - netic role.23, 25 Antibodies against Gp Ia/IIa, HLA I and Gp Ib/Ix complex are less frequently detected. Serum levels of TPO are higher in thrombocytopenic SLE patients compared to normal controls, and megakaryo - cytes are increased in their bone marrow. Nevertheless, antibodies against TPO and c-mpl have been identified in 23%-39% of patients. 25,28 These patients often have lower platelet counts, although their exact role in the pathogenesis of thrombocytopenia remains obscure. In some cases the development of anti-TPO antibodies is associated with poor response to administration of cor - ticosteroids (CS).30 Antiphospholipid antibodies against cardiolipin, phos - phatidylinositol, prothrombin as well as lupus anticoag - ulant are detected in a substantial proportion of patients with SLE and thrombocytopenia31-33 and they are signifi- cantly associated with thrombocytopenia in many stud - ies.34,35 Membrane phospholipids that cross-react anti - genically with cardiolipin are exposed after cell damage and comprise the trigger for the development of anti-car- diolipin antibodies.36 Finally, autoantibodies against the CD40-ligand molecule on the surface of T lymphocytes appear to have a role in the development of thrombocytopenia in SLE. CD40-li - gant is linked to the CD40 antigen on the B lymphocytes surface leading to their activation and autoantibody pro- duction. In a study by Nakamura et al. 37 such autoanti - bodies were detected in seven (6%) of 125 patients with SLE. The incidence of thrombocytopenia was higher in positive patients in comparison to the negative ones (100% vs 14%). LABORATORY FINDINGS Laboratory investigation of patients with SLE and throm- bocytopenia begins with microscopic examination of peripheral blood smears for the estimation of platelet count and size and the presence of schistocytes (frag - mented red blood cells). In case of coexistence of throm- bocytopenia and anemia the assessment of reticulocyte count and direct Coombs test is warranted. Abnormal lymphocyte morphology as well as lymphadenopathy should raise suspicion of a lymphoproliferative disease and prompt investigation with imaging studies, immuno- globulin measurement, bone marrow and lymph node biopsy. Coagulation studies, LDH, bilirubin levels and antiphospholipid antibodies are also important to ex - clude TTP , disseminated intravascular coagulation and antiphospholipid syndrome. The measurement of antiplatelet antibodies may be re - quired in patients with severe thrombocytopenia, espe - cially in prednisone refractory ones. It should however be noted that failure to detect them does not preclude au - toimmune thrombocytopenia in patients with SLE. This fact along with the limited availability of these tests has made their usefulness controversial. High antibody titers against double-stranded DNA (an - LUPUS THROMBOCYTOPENIA: PATHOGENESIS AND THERAPEUTIC IMPLICATIONS MEDITERRANEAN JOURNAL OF RHEUMATOLOGY 28 1 2017 22 MEDITERRANEAN JOURNAL OF RHEUMATOLOGY 28 1 201722 ti-dsDNA) coupled with low levels of C3 and C4 advo - cate activity of SLE, although thrombocytopenia itself has not been found to be associated with anti-dsDNA.11 On the other hand low levels of C3 or CH50 has been associated with thrombocytopenia.12 Bone marrow aspiration may be needed in severe or per- sistent thrombocytopenia, particularly when there is sus- picion of drug toxicity or hemophagocytosis or when it is accompanied by other cytopenias. Bone marrow findings are heterogeneous between studies, ranging from hypo- to hypercellular marrow and low, normal or high megakaryo- cyte number. Increased reticulin proliferation, lymphocy- tosis, plasmacytosis and morphological abnormalities of megakaryocytes notably aggregation, reduced lobulation and pycnotic appearance, as well as necrotic lesions in the bone marrow stroma have been reported.25, 38 THERAPEUTIC MANAGEMENT Thrombocytopenia in SLE may be acute in onset and extremely severe. Severe thrombocytopenia requires emergency therapy in order to eliminate hemorrhagic complications and achieve a complete or partial plate - let response. Maintenance treatment is usually needed to prevent relapse. Initial treatment does not differ from ITP . The decision to treat when thrombocytopenia is the sole disorder in SLE depends on the hemorrhagic man - ifestations and platelet count. Generally, patients with a platelet count > 50x109/l without bleeding manifestations do not require treatment in the absence of coexistent he- mostatic disorders, anticoagulation treatment, trauma or major surgery. Corticosteroids are the cornerstone of initial treatment. High dose oral prednisolone or pulse high dose methyl - prednisolone (MP) with or without intravenous immune globulin (IVIG) are used in the acute phase. Second line agents include hydroxychloroquine (HCQ), danazol, immunosuppressive drugs like azathioprine (AZA), cy - closporine (CSA), mycophenolate mofetil (MMF), cyclo - phosphamide (CYC), and biological therapies such as rituximab. The thrombopoietin receptor agonists romi - plostim and eltrombopag have been widely used for the treatment of ITP and they also seem to have a role in SLE thrombocytopenia. Splenectomy is indicated for re- current or resistant cases. It should be noted that none of the above agents have been tested in a randomized fashion in the context of SLE thrombocytopenia. In a recent study, Jin-Hee Jung et al. 39 retrospectively examined the clinical characteristics and prognosis of 230 patients with SLE in regard to degree of thrombo - cytopenia and response to treatment. They found high - er mortality (15% vs 9%) among patients with severe thrombocytopenia (<20x109/l) and lower mortality in pa - tients with complete remission of thrombocytopenia after treatment. No difference between therapeutic modalities was found, regarding complete remission rate, except a lower incidence of complete remission in the danazol group. Similarly, Ziakas et al. performed a case-control study in 632 patients and did not find a different relapse free interval between patients receiving low or high inten- sity regimens (CS plus AZA vs CS plus CYC).12 Other causes of thrombocytopenia beyond auto-im - mune will not be further discussed in the below section. FIRST LINE THERAPY Corticosteroids Corticosteroids (CS) are administered at the conventional dose of 1-1.5 mg/kg of prednisone qd with subsequent slow tapering after achieving a stable platelet response or as pulses of methylprednisolone (MP) iv (500-1000 mg/ day for 3 days). There is no significant advantage of the higher dose MP scheme (3-5g), which may be associ - ated with more complications like infections. 40 Anti-TPO receptor antibodies may be associated with a subopti - mal response to CS.30 CS appear to produce a satisfac- tory response in the majority of patients, but eventually most patients relapse.2,41 If there is no response after four weeks of CS therapy the patient is considered resistant and a second line treatment is sought. Intravenous Immune Globulin (IVIG) IVIG is used in the acute management of the bleeding patient with severe SLE thrombocytopenia at a dose of 1g/kg for 1 to 2 days, as recommended in the recent 2011 American Society of Hematology guidelines for ITP42 or at 400mg/kg for five consecutive days.43 It exerts its action by downregulating autoantibody production, neutralization of pathogenic autoantibodies by anti-id - iotypic antibodies, inhibition of complement-mediated damage, modulation of cytokine production, induction of apoptosis in lymphocytes, and modulation of both B- and T-lymphocyte function. Maintenance of remission after repeated lower monthly doses has also been re - ported.44 It is safely used in pregnancy. SECOND LINE THERAPY OR STEROID-SPARING AGENTS Although most patients initially respond to CS, respons - es are not sustained and eventually management calls for second line agents. Alternative treatment is also war- ranted in responding patients who experience debilitat - ing side effects from prolonged CS use. These drugs are used alone or in combination with CS as steroid-sparing agents. There are no evidence-based guidelines to facil- itate selection of one drug over another but certainly the co-existence of other systemic SLE manifestations must be taken into account in order to select the appropri - ate therapy. If thrombocytopenia is mild (>50x109/L) and there is no other evidence of disease there is no need of therapy. 23 TITLE23 LUPUS THROMBOCYTOPENIA: PATHOGENESIS AND THERAPEUTIC IMPLICATIONS Hydroxychloroquine (HCQ) A combination of HCQ and prednisone is effective in many patients.41 Khellaf et al.45 studied the effect of HCQ in either SLE or only ANA positive patients with throm - bocytopenia and insufficient response to CS alone. The coadministration of CS with HCQ resulted in an overall response rate of 60% with a higher rate noted in pa - tients with SLE compared to those with ANA only (83% vs 50%). Arnal et al. reported on the long-term results of HCQ plus CS in 11 patients failing CS alone, in 64% of whom a lasting response was obtained.41 Danazol Danazol is a synthetic androgen with a proven activity in many types of thrombocytopenia including that of SLE. 46,47 Its mecha - nism of action is unclear but involves impairment of mac- rophage-mediated clearance of antibody-coated plate - lets via decreased Fc receptor expression. It is a well tolerated drug, with the main side effects being hirsutism and an increased risk of thromboembolic episodes. The best responses have been observed after prolonged administration at a daily dose of 600-800mg, alone or in combination with AZA or CS. Following a stable re - sponse for at least 12 months the dose can be lowered or interrupted as it has been associated with lasting re - sponses even after discontinuation.48 Azathioprine AZA is a steroid-sparing agent with sparse reports on lupus thrombocytopenia, used alone or in combination with CS.49,50 It is administered at a dose of up to 2mg/kg/ day. If a response occurs, therapy should be continued at full doses for at least 12 months and then tapered gradually. Cyclosporine In a small number of patients with SLE and thrombocy - topenia CSA appeared to be beneficial as a second line or steroid-sparing agent. 51,52 The optimal dose has not been defined and patients may respond in doses much lower than those used in transplantation (<3-5mg/kg/ day). However, caution should be used because of its renal toxicity. Cyclophosphamide Cyclophosphamide is of particular importance in the treatment of severe refractory thrombocytopenia of SLE.52 It is administered in IV pulses (0,75-1 g/m 2 or 10–15 mg/kg every 4 weeks for four to six months). In the retrospective study of Boumpas et al.53 in 7 patients with SLE and thrombocytopenia refractory to CS, CYC at a dose of 0,75-1 g/m 2 every 4 weeks resulted in all patients achieving CR within 2-18 weeks. In four patients the subsequent administration of low dose prednisolone was sufficient to maintain remission of thrombocytopenia throughout a long follow up period (mean 5.6 years). Al - ternatively, Park et al.54 applied the low dose CYC proto- col (500 mg of CYC every two weeks for three months), as used in the Euro-Lupus Nephritis Trial, in 2 refractory patients achieving a good response which was main - tained thereafter by a combination of low dose prednis - olone with AZA or MMF. This lower dose can improve tolerability of CYC by reducing the risk of neutropenia. Mycophenolate mofetil MMF, a prodrug of mycophenolic acid, which inhibits inosine-5’monophosphate dehydrogenase, is an immu- nosuppressive drug successfully administrated both as treatment of severe resistant thrombocytopenia and as maintenance.55,56 Its main use has been lupus nephritis and it is less toxic than CYC. Splenectomy Splenectomy has been successfully performed is SLE thrombocytopenia.57 This procedure has been widely used, with excellent long-term results in recurrent ITP .58 However, in SLE there is a risk of a flare of the disease because the spleen is a prominent site of immune com - plexes’ clearance, and additionally a predisposition to infections due to the often prolonged use of immu - nosuppressants in these patients. 1 Prophylactic vac - cinations against pneumonococcus sp, haemophilus influenza type B and meningitis are mandatory before the procedure and antibiotic prophylaxis for at least two years postsplenectomy are recommended, particularly in patients with additional chronic hypocomplementemia. Efficacy of splenectomy is controversial in SLE59 with one study reporting only 2 out of fourteen patients maintain - ing response without the need of CS or other drugs. 60 Thus, it is reserved for the most resistant cases. More studies are needed to define the safety and efficacy of the procedure. NOVEL THERAPIES Rituximab SLE is known to be associated with polyclonal B-cell hyper reactivity. Rituximab is a chimeric monoclonal an - tibody that binds to the CD20 antigen, found on the sur- face of B lymphocytes, inducing depletion of B cells. In SLE, it has been used at high doses of 1000 mg for one or multiple doses to as low as 100 to 200mg per week for 1-4 doses,61-63 the lower doses reserved for patients with cytopenias only. 64 Although retrospective or open label studies and case reports have shown efficacy over 60% in lupus thrombocytopenia, optimal dose has not been defined and duration of response is somehow short lived.61,65 Newer, type II, anti-CD20 mAbs like obinotu - zumab may be more effective in this context due to more potent B cell depletion.66 On the other hand, results from MEDITERRANEAN JOURNAL OF RHEUMATOLOGY 28 1 2017 24 MEDITERRANEAN JOURNAL OF RHEUMATOLOGY 28 1 201724 two randomized controlled studies (EXPLORER 67 and LUNAR68 trials) using rituximab in an intention-to-treat SLE have been disappointing 69 showing no significant benefit over placebo showing no significant benefit over placebo in BILAG scores and renal response respective- ly. This unexpected outcome has been partially attribut - ed to suboptimal trial design and concurrent therapies, but it has also been speculated that a feedback effect, characterized by rising BAFF levels, may play a role to postrituximab SLE flares.69 The exact place of rituximab, regarding its use early or late in the course of thrombocy- topenia remains to be defined by further studies. Belimumab Belimumab is a human IgG1 λ monoclonal antibody that binds to and inhibits B-cell activating factor (BAFF), thus inhibiting the biological activity of B lymphocytes and inducing apoptosis of autoreactive B lymphocytes. 70 In SLE BAFF is overexpressed, enhancing the survival of B lymphocytes, including autoreactive B cell populations.71 In the post hoc analysis of two Lupus phase III random- ized trials, belimumab was significantly associated with less worsening in the haematological domain, but there are currently no trials of belimumab for immune thrombo- cytopenia or hematological disorders in general.70 THROMBOPOIETIN RECEPTOR AGONISTS Romiplostim and eltrombopag are thrombopoietin recep- tor agonists which exhibit their action by inducing prolif - eration and differentiation of megakaryocyte progenitors, maturation of megakaryocytes and increased platelet pro- duction.72 They have displayed excellent results in phase III randomized trials73,74 and have been approved since 2008 as second line agents for ITP refractory to other treatments. So far, the efficacy of these agents in lupus thrombocyto- penia has only been assessed in sparse case reports. In one report a patient with Evans syndrome refractory to rituximab was successfully managed with romiplostim,75 whereas in another case romiplostim facilitated response in a pregnant thrombocytopenic patient with SLE.76 Con- trasting to these results a young SLE patient developed thrombotic microangiopathy with renal failure after romi- plostim therapy.77 Maroun et al. 78 reported on three pa - tients with SLE thrombocytopenia in which administration of eltrombopag was successful as steroid-sparing treat- ment. Another patient with refractory thrombocytopenia achieved a complete response after eltrombopag treat - ment.79 Eltrombopag was also efficient in a patient with lupus-associated amegakaryocytic thrombocytopenia. 80 The thrombotic risk must be taken into account though. In a recent report, a patient with antiphospholipid syndrome presented with fatal thrombotic complications one month after starting eltrombopag for severe thrombocytopenia and while platelets had normalized.81

Thrombocytopenia (<100x10 9/L) has been reported in 20% to 40% of patients with SLE and is usually attributed to an autoimmune mechanism similar to that of idiopathic immune thrombocytopenia. It may be the first manifesta- tion of lupus in up to 16% of patients, presenting months or as early as 10 years before diagnosis. Many studies have found an association between thrombocytopenia and a higher mortality from SLE, although the pattern of thrombocytopenia (severity, onset) is not clearly defined. There are no evidence-based recommendations for the treatment of SLE thrombocytopenia due to the absence of randomized controlled trials. Acute therapy of severe thrombocytopenia or for the bleeding patient is the same as in ITP , high-dose CS and IVIG-based, but maintenance usually calls for the addition of other immunosuppressive drugs (hydroxychloroquine, danazol, azathioprine, cyc - losporine, mycophenolate mofetil, cyclophosphamide), because response is often short-lived and patients have other organ involvement too. New drugs such as mono- clonal antibodies and thrombopoietin receptor agonists are emerging as steroid-sparing modalities but safety and efficacy have yet to be established. Randomized controlled trials are needed to define the superiority of any second- line agent over the others. CONFLICT OF INTEREST The authors of this manuscript declare no conflict of in - terest.

1. Hepburn A L, Narat S, Mason J C. The management of peripheral blood cytopenias in systemic lupus erythematosus. Rheumatology (Oxford) 2010;49:2243-54. 2. Fayyaz A, Igoe A, Kurien B T, Danda D, James J A, Stafford H A, et al. Haematological manifestations of lupus. Lupus Sci Med 2015;2:e000078. 3. Feletar M, Ibanez D, Urowitz M B, Gladman D D. The impact of the 1997 update of the American College of Rheumatology revised criteria for the classification of systemic lupus erythematosus: what has been changed? Arthritis Rheum 2003;48:2067-9. 4. Petri M, Orbai A M, Alarcon G S, Gordon C, Merrill J T, Fortin P R, et al. Derivation and validation of the Systemic Lupus International Collaborating Clinics classification criteria for systemic lupus erythematosus. Arthritis Rheum 2012;64:2677-86. 5. Tan E M, Cohen A S, Fries J F, Masi A T, McShane D J, Rothfield N F, et al. The 1982 revised criteria for the classification of systemic lupus erythematosus. Arthritis Rheum 1982;25:1271-7. 6. Cervera R, Khamashta M A, Font J, Sebastiani G D, Gil A, Lavilla P , et al. Morbidity and mortality in systemic lupus erythematosus during a 10-year period: a comparison of early and late manifestations in a cohort of 1,000 patients. Medicine (Baltimore) 2003;82:299-308. 7. Mok C C, Lee K W, Ho C T, Lau C S, Wong R W. A prospective study of survival and prognostic indicators of systemic lupus erythematosus in a southern Chinese population. Rheumatology (Oxford) 2000;39:399-406. 8. Vila L M, Alarcon G S, McGwin G, Jr., Friedman A W, Baethge B A, Bastian HM, et al. Early clinical manifestations, disease activity and damage of systemic lupus erythematosus among two distinct US Hispanic subpopulations. Rheumatology (Oxford) 2004;43:358- 25 TITLE25 LUPUS THROMBOCYTOPENIA: PATHOGENESIS AND THERAPEUTIC IMPLICATIONS 63. 9. Mestanza-Peralta M, Ariza-Ariza R, Cardiel M H, Alcocer-Varela J. Thrombocytopenic purpura as initial manifestation of systemic lupus erythematosus. J Rheumatol 1997;24:867-70. 10. Rabinowitz Y, Dameshek W. Systemic Lupus Erythematosus after “idiopathic” thrombocytopenic purpura: a review. A study of systemic lupus erythematosus occurring after 78 splenectomies for «idiopathic» thrombocytopenic purpura, with a review of the pertinent literature*†. Ann Intern Med 1960;52:1-28. 11. Sultan S M, Begum S, Isenberg D A. Prevalence, patterns of disease and outcome in patients with systemic lupus erythematosus who develop severe haematological problems. Rheumatology (Oxford) 2003;42:230-4. 12. Ziakas P D, Giannouli S, Zintzaras E, Tzioufas A G, Voulgarelis M. Lupus thrombocytopenia: clinical implications and prognostic significance. Ann Rheum Dis 2005;64:1366-9. 13. Nesher G, Hanna V E, Moore T L, Hersh M, Osborn T G. Thrombotic microangiographic hemolytic anemia in systemic lupus erythematosus. Semin Arthritis Rheum 1994;24:165-72. 14. Vaidya S, Abul-ezz S, Lipsmeyer E. Thrombotic thrombocytopenic purpura and systemic lupus erythematosus. Scand J Rheumatol 2001;30:308-10. 15. Dhote R, Simon J, Papo T, Detournay B, Sailler L, Andre M H, et al. Reactive hemophagocytic syndrome in adult systemic disease: report of twenty-six cases and literature review. Arthritis Rheum 2003;49:633-9. 16. Pistiner M, Wallace D J, Nessim S, Metzger A L, Klinenberg JR. Lupus erythematosus in the 1980s: a survey of 570 patients. Semin Arthritis Rheum 1991;21:55-64. 17. Nossent J, Swaak A. Prevalence and Significance of Haematological Abnormalities in Patients with Systemic Lupus Erythematosus. QJM 1991;80:605-12. 18. Miller M H, Urowitz M B, Gladman D D. The significance of thrombocytopenia in systemic lupus erythematosus. Arthritis Rheum 1983;26:1181-86. 19. Alger M, Alarcon-Segovia D, Rivero S J. Hemolytic anemia and thrombocytopenic purpura: two related subsets of systemic lupus erythematosus. J Rheumatol 1977;4:351-7. 20. Reveille J D, Bartolucci A, Alarcon G S. Prognosis in systemic lupus erythematosus. Negative impact of increasing age at onset, black race, and thrombocytopenia, as well as causes of death. Arthritis Rheum 1990;33:37-48. 21. Sestak A L, Shaver T S, Moser K L, Neas B R, Harley J B. Familial aggregation of lupus and autoimmunity in an unusual multiplex pedigree. J Rheumatol 1999;26:1495-9. 22. Scofield R H, Bruner G R, Kelly J A, Kilpatrick J, Bacino D, Nath S K, et al. Thrombocytopenia identifies a severe familial phenotype of systemic lupus erythematosus and reveals genetic linkages at 1q22 and 11p13. Blood 2003;101:992-7. 23. Lipp E, von Felten A, Sax H, Muller D, Berchtold P . Antibodies against platelet glycoproteins and antiphospholipid antibodies in autoimmune thrombocytopenia. Eur J Haematol 1998;60:283-8. 24. Michel M, Lee K, Piette J C, Fromont P , Schaeffer A, Bierling P , et al. Platelet autoantibodies and lupus-associated thrombocytopenia. Br J Haematol 2002;119:354-8. 25. Ziakas P D, Routsias J G, Giannouli S, Tasidou A, Tzioufas A G, Voulgarelis M. Suspects in the tale of lupus-associated thrombocytopenia. Clin Exp Immunol 2006;145:71-80. 26. Macchi L, Rispal P , Clofent-Sanchez G, Pellegrin J L, Nurden P , Leng B, et al. Anti-platelet antibodies in patients with systemic lupus erythematosus and the primary antiphospholipid antibody syndrome: their relationship with the observed thrombocytopenia. Br J Haematol 1997;98:336-41. 27. Diz-Kucukkaya R, Hacihanefioglu A, Yenerel M, Turgut M, Keskin H, Nalcaci M, et al. Antiphospholipid antibodies and antiphospholipid syndrome in patients presenting with immune thrombocytopenic purpura: a prospective cohort study. Blood 2001;98:1760-4. 28. Fureder W, Firbas U, Nichol J L, Pistillo J, Winkler S, Hiesberger H, et al. Serum thrombopoietin levels and anti-thrombopoietin antibodies in systemic lupus erythematosus. Lupus 2002;11:221- 6. 29. Kuwana M, Okazaki Y, Kajihara M, Kaburaki J, Miyazaki H, Kawakami Y, et al. Autoantibody to c-Mpl (thrombopoietin receptor) in systemic lupus erythematosus: relationship to thrombocytopenia with megakaryocytic hypoplasia. Arthritis Rheum 2002;46:2148- 59. 30. Kuwana M, Kaburaki J, Okazaki Y, Miyazaki H, Ikeda Y. Two types of autoantibody-mediated thrombocytopenia in patients with systemic lupus erythematosus. Rheumatology (Oxford) 2006;45:851-4. 31. Nojima J, Kuratsune H, Suehisa E, Futsukaichi Y, Yamanishi H, Machii T, et al. Association between the prevalence of antibodies to beta(2)-glycoprotein I, prothrombin, protein C, protein S, and annexin V in patients with systemic lupus erythematosus and thrombotic and thrombocytopenic complications. Clin Chem 2001;47:1008-15. 32. Munoz-Rodriguez F J, Reverter J C, Font J, Tassies D, Cervera R, Espinosa G, et al. Prevalence and clinical significance of antiprothrombin antibodies in patients with systemic lupus erythematosus or with primary antiphospholipid syndrome. Haematologica 2000;85:632-7. 33. Abu-Shakra M, Gladman D D, Urowitz M B, Farewell V. Anticardiolipin antibodies in systemic lupus erythematosus: clinical and laboratory correlations. Am J Med 1995;99:624-8. 34. Rupin A, Gruel Y, Poumier-Gaschard P , Chassaigne M, Leroy J, Bardos P . Thrombocytopenia in systemic lupus erythematosus: association with antiplatelet and anticardiolipin antibodies. Clin Immunol Immunopathol 1990;55:418-26. 35. Fabris F, Steffan A, Cordiano I, Borzini P , Luzzatto G, Randi M L, et al. Specific antiplatelet autoantibodies in patients with antiphospholipid antibodies and thrombocytopenia. Eur J Haematol 1994;53:232-6. 36. Arnout J, Vermylen J. Current status and implications of autoimmune antiphospholipid antibodies in relation to thrombotic disease. J Thromb Haemost 2003;1:931-42. 37. Nakamura M, Tanaka Y, Satoh T, Kawai M, Hirakata M, Kaburaki J, et al. Autoantibody to CD40 ligand in systemic lupus erythematosus: association with thrombocytopenia but not thromboembolism. Rheumatology (Oxford) 2006;45:150-6. 38. Hepburn A L, Lampert I A, Boyle J J, Horncastle D, Ng W F, Layton M, et al. In vivo evidence for apoptosis in the bone marrow in systemic lupus erythematosus. Ann Rheum Dis 2007;66:1106-9. 39. Jung J H, Soh M S, Ahn Y H, Um Y J, Jung J Y, Suh C H, et al. Thrombocytopenia in Systemic Lupus Erythematosus: Clinical Manifestations, Treatment, and Prognosis in 230 Patients. Medicine 2016;95:e2818. 40. Badsha H, Kong K O, Lian T Y, Chan S P , Edwards C J, Chng H H. Low-dose pulse methylprednisolone for systemic lupus erythematosus flares is efficacious and has a decreased risk of infectious complications. Lupus 2002;11:508-13. 41. Arnal C, Piette J C, Leone J, Taillan B, Hachulla E, Roudot-Thoraval F, et al. Treatment of severe immune thrombocytopenia associated with systemic lupus erythematosus: 59 cases. J Rheumatol 2002;29:75-83. 42. Neunert C, Lim W, Crowther M, Cohen A, Solberg L, Crowther M A. The American Society of Hematology 2011 evidence- based practice guideline for immune thrombocytopenia. Blood 2011;117:4190-207. 43. Zandman-Goddard G, Levy Y, Shoenfeld Y. Intravenous immunoglobulin therapy and systemic lupus erythematosus. Clin Rev Allergy Immunol 2005;29:219-28. 44. Maeshima E, Kida Y, Goda M, Minami Y. A case of systemic lupus erythematosus expressing intractable thrombocytopenia remedied effectively by intermittent and continuous administrations of a small amount of immune globulin. Mod Rheumatol 2006;16:239-42. 45. Khellaf M, Chabrol A, Mahevas M, Roudot-Thoraval F, Limal N, Languille L, et al. Hydroxychloroquine is a good second-line treatment for adults with immune thrombocytopenia and positive MEDITERRANEAN JOURNAL OF RHEUMATOLOGY 28 1 2017 26 MEDITERRANEAN JOURNAL OF RHEUMATOLOGY 28 1 201726 antinuclear antibodies. Am J Hematol 2014;89:194-8. 46. Cervera H, Jara L J, Pizarro S, Enkerlin H L, Fernandez M, Medina F, et al. Danazol for systemic lupus erythematosus with refractory autoimmune thrombocytopenia or Evans’ syndrome. J Rheumatol 1995;22:1867-71. 47. Wong K L. Danazol in treatment of lupus thrombocytopenia. Asian Pac J Allergy Immunol 1991;9:125-9. 48. Cines D B, Bussel J B. How I treat idiopathic thrombocytopenic purpura (ITP). Blood 2005;106:2244-51. 49. Goebel K M, Gassel W D, Goebel F D. Evaluation of azathioprine in autoimmune thrombocytopenia and lupus erythematosus. Scand J Haematol 1973;10:28-34. 50. Abu-Shakra M, Shoenfeld Y. Azathioprine therapy for patients with systemic lupus erythematosus. Lupus 2001;10:152-3. 51. Manger K, Kalden J R, Manger B. Cyclosporin A in the treatment of systemic lupus erythematosus: results of an open clinical study. Br J Rheumatol 1996;35:669-75. 52. Sekigawa I, Ogasawara H, Sugiyama M, Kaneko H, Hishikawa T, Tokano Y, et al. Extremely low dose treatment of cyclosporine for autoimmune diseases. Clin Exp Rheumatol 1998;16:352. 53. Boumpas D T, Barez S, Klippel J H, Balow J E. Intermittent cyclophosphamide for the treatment of autoimmune thrombocytopenia in systemic lupus erythematosus. Ann Intern Med 1990;112:674-7. 54. Park H J, Kang M I, Kang Y, Chung S J, Lee S W, Park Y B, et al. Two cases of refractory thrombocytopenia in systemic lupus erythematosus that responded to intravenous low-dose cyclophosphamide. J Korean Med Sci 2013;28:472-5. 55. Chang H K. Successful treatment of refractory thrombocytopenia with mycophenolate mofetil in a patient with systemic lupus erythematosus. J Korean Med Sci 2005;20:883-5. 56. Vasoo S, Thumboo J, Fong K Y. Refractory immune thrombocytopenia in systemic lupus erythematosus: response to mycophenolate mofetil. Lupus 2003;12:630-2. 57. You Y N, Tefferi A, Nagorney D M. Outcome of splenectomy for thrombocytopenia associated with systemic lupus erythematosus. Ann Surg 2004;240:286-92. 58. Vianelli N, Palandri F, Polverelli N, Stasi R, Joelsson J, Johansson E, et al. Splenectomy as a curative treatment for immune thrombocytopenia: a retrospective analysis of 233 patients with a minimum follow up of 10 years. Haematologica 2013;98:875-80. 59. Alarcon-Segovia D. Splenectomy has a limited role in the management of lupus with thrombocytopenia. J Rheumatol 2002;29:1-2. 60. Hall S, McCormick J L, Jr., Greipp P R, Michet C J, Jr., McKenna C H. Splenectomy does not cure the thrombocytopenia of systemic lupus erythematosus. Ann Intern Med 1985;102:325-8. 61. Jiang B, Li T, Guo L, Shen H, Ye S, Chen S. Efficacy and Safety of Rituximab in Systemic Lupus Erythematosus and Sjogren Syndrome Patients With Refractory Thrombocytopenia: A Retrospective Study of 21 Cases. J Clin Rheumatol 2015;21:244- 50. 62. Gupta R K, Ezeonyeji A N, Thomas A S, Scully M A, Ehrenstein M R, Isenberg D A. A case of pure red cell aplasia and immune thrombocytopenia complicating systemic lupus erythematosus: response to rituximab and cyclophosphamide. Lupus 2011;20:1547-50. 63. Lateef A, Lahiri M, Teng GG, Vasoo S. Use of rituximab in the treatment of refractory systemic lupus erythematosus: Singapore experience. Lupus 2010;19:765-70. 64. Chen H, Zheng W, Su J, Xu D, Wang Q, Leng X, et al. Low-dose rituximab therapy for refractory thrombocytopenia in patients with systemic lupus erythematosus--a prospective pilot study. Rheumatology (Oxford) 2011;50:1640-4. 65. Garcia-Carrasco M, Mendoza-Pinto C, Sandoval-Cruz M, Soto- Vega E, Beltran-Castillo A, Jimenez-Hernandez M, et al. Anti-CD20 therapy in patients with refractory systemic lupus erythematosus: a longitudinal analysis of 52 Hispanic patients. Lupus 2010;19:213- 9. 66. Reddy V, Cambridge G, Isenberg D A, Glennie M J, Cragg M S, Leandro M. Internalization of rituximab and the efficiency of B Cell depletion in rheumatoid arthritis and systemic lupus erythematosus. Arthritis Rheumatol 2015;67:2046-55. 67. Merrill J T, Neuwelt C M, Wallace D J, Shanahan J C, Latinis K M, Oates J C, et al. Efficacy and safety of rituximab in moderately- to-severely active systemic lupus erythematosus: the randomized, double-blind, phase II/III systemic lupus erythematosus evaluation of rituximab trial. Arthritis Rheum 2010;62:222-33. 68. Rovin B H, Furie R, Latinis K, Looney R J, Fervenza F C, Sanchez- Guerrero J, et al. Efficacy and safety of rituximab in patients with active proliferative lupus nephritis: the Lupus Nephritis Assessment with Rituximab study. Arthritis Rheum 2012;64:1215-26. 69. Ehrenstein M R, Wing C. The BAFFling effects of rituximab in lupus: danger ahead? Nat Rev Rheumatol 2016;12:367-72. 70. Manzi S, Sanchez-Guerrero J, Merrill J T, Furie R, Gladman D, Navarra S V, et al. Effects of belimumab, a B lymphocyte stimulator- specific inhibitor, on disease activity across multiple organ domains in patients with systemic lupus erythematosus: combined results from two phase III trials. Ann Rheum Dis 2012;71:1833-8. 71. Cancro M P , D’Cruz D P , Khamashta M A. The role of B lymphocyte stimulator (BLyS) in systemic lupus erythematosus. J Clin Invest 2009;119:1066-73. 72. Wang B, Nichol J L, Sullivan J T. Pharmacodynamics and pharmacokinetics of AMG 531, a novel thrombopoietin receptor ligand. Clin Pharmacol Ther 2004;76:628-38. 73. Bussel J B, Cheng G, Saleh M N, Psaila B, Kovaleva L, Meddeb B, et al. Eltrombopag for the treatment of chronic idiopathic thrombocytopenic purpura. N Engl J Med 2007;357:2237-47. 74. Kuter D J, Bussel J B, Lyons R M, Pullarkat V, Gernsheimer T B, Senecal F M, et al. Efficacy of romiplostim in patients with chronic immune thrombocytopenic purpura: a double-blind randomised controlled trial. Lancet 2008;371:395-403. 75. Gonzalez-Nieto J A, Martin-Suarez I, Quattrino S, Ortiz-Lopez E, Munoz-Beamud F R, Colchero-Fernandez J, et al. The efficacy of romiplostim in the treatment of severe thrombocytopenia associated to Evans syndrome refractory to rituximab. Lupus 2011;20:1321-3. 76. Alkaabi J K, Alkindi S, Riyami N A, Zia F, Balla L M, Balla S M. Successful treatment of severe thrombocytopenia with romiplostim in a pregnant patient with systemic lupus erythematosus. Lupus 2012;21:1571-4. 77. Tomov S, Lazarchick J, Self S E, Bruner E T, Budisavljevic M N. Kidney-limited thrombotic microangiopathy in patients with SLE treated with romiplostim. Lupus 2013;22:504-9. 78. Maroun M C, Ososki R, Andersen J C, Dhar J P . Eltrombopag as steroid sparing therapy for immune thrombocytopenic purpura in systemic lupus erythematosus. Lupus 2015;24:746-50. 79. Scheinberg P , Singulane C C, Barbosa L S, Scheinberg M. Successful platelet count recovery in lupus-associated thrombocytopenia with the thrombopoietin agonist eltrombopag. Clin Rheumatol 2014;33:1347-9. 80. Cela I, Miller I J, Katz R S, Rizman A, Shammo J M. Successful treatment of amegakaryocytic thrombocytopenia with eltrombopag in a patient with systemic lupus erythematosus (SLE). Clin Adv Hematol Oncol 2010;8:806-9. 81. Boulon C, Vircoulon M, Constans J. Eltrombopag in systemic lupus erythematosus with antiphospholipid syndrome: thrombotic events. Lupus 2016;25:331.