Eosinophilic Granulomatosis With Polyangiitis With Thrombotic Microangiopathy: Is Simultaneous Systemic Lupus Erythematosus Associated With Clinical Manifestations?

Abstract Eosinophilic granulomatosis with polyangiitis (EGPA) is one of the antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, which is characterized by vasculitis of the small to medium-sized vessels. On the contrary, thrombotic microangiopathy (TMA) is a life-threatening condition which can cause ischemic organ injury. Although several case reports have described patients with TMA associated with ANCA-associated vasculitis except for EGPA, there are no previous case reports of EGPA associated with TMA. A 71-year-old Japanese man was diagnosed with EGPA based on his asthma, eosinophilia, lung opacity, refractory sinusitis, and positive myeloperoxidase-ANCA. He was also diagnosed with TMA based on peripheral schizocytes and hemolytic anemia. We performed plasmapheresis and started high-dose corticosteroid therapy; thereafter, he improved promptly. His case also fulfilled the classification criteria of systemic lupus erythematosus (SLE) based on the pleural effusion, renal disorder, anemia, thrombocytopenia, positive antidouble-stranded DNA antibody, and low complement. Elements of SLE were thought to affect his clinical course. We reviewed 11 patients with EGPA or hypereosinophilic syndrome (HES) associated with SLE, including our case. Patients with EGPA or HES associated with SLE had more heart complications than patients with simple EGPA or simple HES did. Patients with EGPA or HES associated with SLE had more pleural effusion than patients with simple SLE did. Clinical manifestations of eosinophilia with SLE or SLE with eosinophilia may differ from simple SLE or simple eosinophilia.


INTRODUCTION
A ntineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterized by vasculitis of the small to medium-sized vessels; however, its etiology remains unknown. There are three types of AAV: eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA). On the contrary, thrombotic microangiopathy (TMA) is characterized by thrombocytopenia and microangiopathic hemolytic anemia, which can cause ischemic organ injury of brain, kidneys, heart, pancreas, liver, and lungs. TMA is a very severe disease and needs therapeutic options such as plasmapheresis. Several case reports have described patients with MPA and GPA associated with TMA. Regarding only MPA and GPA, 14% of patients are reported to have TMA. 1 However, EGPA associated with TMA have not ever been reported.
We present a case of EGPA with TMA, which was thought to be associated with elements of SLE including hypocomplementemia.
weeks before his admission to our hospital, his platelet count declined to 20,000/mL, and petechia and palpable purpura emerged on both legs. On admission to our hospital, his dyspnea was observed all day. Eleven years earlier, he was diagnosed with bronchial asthma and was prescribed inhaled glucocorticoids. He had also undergone an operation for bilateral sinusitis of maxillary sinuses 2 years before this admission. He was a psychiatrist. He did not have any family history of rheumatic diseases.
The physical examination results at the present admission were as follows: body temperature 37.88C; blood pressure 122/82 mm Hg; pulse rate 100/min; and respiratory rate 30/min. Auscultation of the chest revealed wheezing over the entire lung field. There was pitting edema in the both lower legs. Petechia and palpable purpura on both legs were seen (Fig. 1).
Head computed tomography (CT) showed bilateral sinusitis of maxillary sinuses.
A chest CT showed peripheral ground glass opacity, dilated heart, and large amount of pleural effusion (Fig. 2). A magnetic resonance image (MRI) of the patient's heart showed intraventricular thrombus and thin endocardium with high-intensity signal (Fig. 3). A bone marrow specimen showed prominent eosinophilic bone marrow. FIP1L1-PDGFRA fusion gene and t(5;12)(q31-q33;p12), which is often observed in myeloproliferative neoplasms with prominent eosinophilia, were both negative.
The patient's poor condition and platelet decline precluded renal biopsy. Because he had asthma, eosinophilia >10%, pulmonary infiltrates (non-fixed), and paranasal sinus abnormality, a diagnosis of EGPA was made, based on the Chapel Hill Consensus Conference criteria, 2 the European Medicines Agency algorithm, 3 and the American College of Rheumatology (ACR) 1990 criteria for the classification of Churg-Strauss syndrome. 4 In addition, because the patient had schizocytes, hemolytic anemia, thrombocytopenia, and renal insufficiency, we also diagnosed TMA. Given the pleural effusion, renal disorder, anemia, thrombocytopenia, positive anti-dsDNA antibody, and low complement, this patient also fulfilled the 1997 American College of Rheumatology classification criteria 5 and the 2012 Systemic Lupus International Collaborating Clinics classification criteria 6 for systemic lupus erythematosus (SLE).
Because his dyspnea worsened progressively day by day and we suspected that he could develop cardiac failure associated with EGPA, we started pulsed methylprednisolone (P-MPSL; 1000 mg/d for 3 consecutive days) and plasmapheresis. Soon after these treatments, the eosinophils disappeared and the patient's dyspnea was improved. Regarding the TMA, the schizocytes disappeared and hemolytic anemia improved. We finished the plasmapheresis after only 2 consecutive days.
The analysis of a skin biopsy specimen 3 days after the P-MPSL was started revealed fragmentation of the lamina elastica interna (Fig. 4A). Immunohistochemical staining of complement factor C3 showed a deposition of C3 in the vessel wall ( Figure 4B).
Following the P-MPSL, we started 55 mg of prednisolone per day, and the patient's MPO-ANCA titer and anti-dsDNA antibody declined gradually. The endocardium with highintensity signal on MRI was diminished 3 weeks after the start  of the P-MPSL. The patient's hypocomplementemia also improved. Eosinophils remained negative.

DISCUSSION
We have described the case of a patient with EGPA associated with TMA. To our knowledge, this is the first case report of EGPA associated with TMA. Chen et al 1 reported that of 220 patients with AAV excluding EGPA, 30 patients (14%) had concomitant renal TMA by pathologic evaluation, and AAV with TMA was not rare. Using PubMed, Manenti et al 7 reviewed 29 cases with AAV with TMA, and they argued that mutations or risk haplotypes in genes encoding alternative complement regulatory proteins associated with TMA. Thurman et al 8 reported that patients with acute-onset diarrheaassociated hemolytic uremic syndrome manifested activation of the alternative pathway of complement that is temporally related to the onset of disease.
In our patient, a skin biopsy revealed C3 deposition on the vessel wall. Magro et al 9 reported that a skin biopsy is of value in establishing a diagnosis of TMA based on the microvascular deposition of complement in the dermis and subcutaneous fat. Because hypocomplementemia also existed in our patient, an alternative pathway of complement may have been associated with his TMA. Nevertheless, this skin biopsy finding seems incompatible to AAV because AAV is defined as pauci-immune vasculitis. However, Brons et al 10 reported that the skin lesions of patients with GPA had immune deposits.
Moreover, Chhabra et al 11 revealed that the observation of immune deposits in cutaneous lesions of GPA is useful as a predictor of an active disease. Although to the best of our knowledge, there are no case reports of EGPA with C3 or immune deposits in skin biopsy, an alternative pathway may have been associated with the occurrence of TMA in our patient.
Our patient also fulfilled the criteria for SLE, which is also associated with TMA. 12 SLE with negative ANA and positive anti-dsDNA antibody is thought to be uncommon in general. However, Almogren et al 13 reported that of 158 patients who were simultaneously tested ANA (immunofluorescence assay on Hep-2 cell) and anti-dsDNA antibody (immuno-enzymatic assay), 24 (15.1%) patients had statuses which were negative  ANA and positive anti-dsDNA antibody. In addition, Craig and Ledue 14 reported that 2 patients had positive anti-dsDNA antibody (Crithidia luciliae immunofluorescence test) among 72 patients with SLE that had negative ANA (immunofluorescence assay on Hep-2 cell) statuses. International recommendations for the assessment of autoantibodies to cellular antigens referred to as antinuclear antibodies 15 says: ''Theoretically, if ANA-indirect immunofluorescence assay is negative, one should not proceed to defining anti-dsDNA antibodies, although if clinical suspicion of SLE is substantial anti-dsDNA antibodies assessment may be requested by the clinician.'' On the basis of these facts, we think that it does not matter to diagnose our case with SLE. Regarding complement, Song et al 16 reported that complement overactivation via both classical and alternative pathways might play an important role in the pathogenesis of renal TMA in lupus nephritis. Eosinophils are rarely seen in SLE. We searched for case reports of EGPA or hypereosinophilic syndrome (HES) associated with SLE by conducting a PubMed search. Table 1 shows the results: 11 patients with EGPA or HES associated with SLE, including our case. We could find only 2 cases of SLE with EGPA, including our case. D'Cruz et al 17 reported a patient who, after 26 years of SLE, developed late-onset asthma and eosinophilia, which progressed to meet the ACR 1990 criteria for the classification of Churg-Strauss syndrome. However, except for fulfilling the Churg-Strauss syndrome criteria, D'Cruz et al's patient did not have features in common with those of our patient.
Regarding heart complications, 5 patients had a heart complication including intracardial thrombus. This is more frequent compared with those in patients with HES, because only 5% of HES patients are reported to have cardiac symptoms. 18 Considering the frequency of heart complications with SLE (pericarditis: 12%-48%, myocarditis: 10%-40%, congestive heart failure: 7%-36% 19 ), the heart complications that are seen in EGPA or HES patients with SLE may be affected by elements of SLE rather than those of EGPA or HES. In our patient, the TMA, thrombocytopenia, and heart complication may reflect elements of SLE, and not only EGPA.
On the contrary, 6 of the 11 reported patients had pleural effusion. In SLE, pleural effusion is seen in approximately 24% of patients, not only at diagnosis but also at any time. 20 SLE with EGPA or HES may have more pleural effusion than simple SLE. Clinical manifestations of eosinophilia with SLE or SLE with eosinophilia may differ from simple SLE or simple eosinophilia.
In conclusion, we have described a patient with EGPA whose case was complicated with TMA. He also fulfilled the SLE criteria, and elements of SLE may have affected his clinical manifestations. Further studies regarding the clinical manifestations and prognosis of EGPA, TMA, and SLE are needed. 21,22,23 -29 CONSENT Written informed consent was obtained from the patient for the publication of this case report. A copy of the written consent is available for review by the Editor of this journal. This case report was approved by the Investigation and Ethics Committee at Nagasaki University Hospital. and AK treated the patient, collected the primary data and critically revised the manuscript. NK is a pathologist, who assessed pathological findings. All authors read and approved the final manuscript.