Acute fulminant myocarditis in a patient with primary Sjögren’s syndrome

Abstract

Sjögren’s syndrome (SS) is an autoimmune disease characterized by hypofunction of salivary and lacrimal glands and systemic multi-organ involvement due to lymphocytic infiltration (1). Myocarditis related to primary Sjögren’s syndrome (pSS) is rare, and its histopathological findings remain unknown (2). Here, we describe a female patient with pSS who developed acute fulminant myocarditis. An endomyocardial biopsy suggested an autoimmune origin. A 35-year-old woman, with a history of Hashimoto’s thyroiditis for 14 years and dry mouth lasting for 6 months, was admitted to a previous hospital owing to high fever, headache, and nausea. Soon afterwards, she went into a state of shock. Systolic blood pressure (BP) was 80 mmHg, and heart rate was 20 beats per minute (bpm) after complete atrioventricular block (CAVB). She was transferred to our hospital after dopamine and lidocaine initiation. She had a high temperature of 39.6°C, BP of 106/ 53 mmHg, and heart rate of 75 bpm. Chest auscultation found no audible heart murmurs or crackles. Electrocardiography exhibited CAVB with wide QRS, STsegment elevation in aVR and V1–3, and ST depression in II, III, aVF, and V4–6. Chest radiography revealed cardiac dilation and congestion. Blood tests returned the following results: creatine kinase 820 U/L (normal 43–157 U/L), C-reactive protein 1.84 mg/dL (normal < 0.30 mg/dL), troponin T > 2.00 ng/mL (normal < 0.014 ng/mL), and brain natriuretic peptide 293.8 pg/ mL (normal < 18.4 pg/mL). Under levothyroxine therapy at 100 μg/day, the thyroid functions were within normal range. Both anti-SS-A and anti-SS-B antibodies were positive [> 1200 U/mL (normal < 10 U/mL) and 12.0 U/mL (normal < 10 U/mL), respectively], but no other autoantibodies were detected. Blood culture results and thorough serological examinations showed no evidence of infections. Echocardiography demonstrated a diffuse hypokinetic wall motion with a decreased left ventricular ejection fraction (LVEF) of 15–20%. Coronary catheterization and angiography demonstrated intact coronary arteries. An endomyocardial biopsy, which was performed on day 2, revealed fibrotic changes in the endomyocardium and interstitium, and lymphocyte infiltration into the myocardial muscle bundles without any evidence of infection, eosinophil infiltration, or giant cell invasion (Figure 1A). The infiltrated lymphocytes mainly consisted of CD3CD8 T cells (Figure 1B and C). Although the results of the Saxon, Schirmer’s, and fluorescein eye stain tests were negative, labial salivary gland biopsy exhibited focal lymphocytic sialadenitis with a focus score of ≥ 1 focus/4 mm. Immunohistochemistry staining of the salivary gland showed infiltration of not only CD20/79a B cells but also CD3CD8 T cells. Finally, the patient was diagnosed with acute fulminant myocarditis associated with pSS, fulfilling the classification criteria for pSS (1). High-dose glucocorticoid and intravenous immunoglobulin therapies were initiated. Her clinical manifestations and cardiac functions immediately improved, with reduction of muscular enzymes. Repeated echocardiography on day 10 demonstrated amelioration of LVEF at 53%. One month after the hospitalization, a second endomyocardial biopsy was performed, showing the decrement of lymphocyte infiltrations, and paired-serum antigen tests for infectious myocarditis showed negative results. To date, her condition is stable without relapse. Although a few reports have described acute myocarditis in patients with pSS, the pathological findings of the endomyocardium are unclear (3–5). Golan et al described a case of pSS with severe cardiomyopathy, purpura, muscular involvement, and peripheral nervous disorders (3). In this case, leucocytoclastic vasculitis, which was diagnosed by a skin biopsy from the purpura, was speculated as the cause of cardiomyopathy. The true pathological findings were undetermined owing to the absence of endomyocardial biopsy. Some organ disorders in patients with SS, such as salivary gland and kidney disorders, have been histopathologically analysed despite inadequate data from endomyocardial specimens. Jasiek et al showed that T-cell infiltration was predominant in 95 patients with pSS with renal involvement (6). In addition, Lavie et al demonstrated that in the early phase of the clinical course of pSS, the main inflammatory cells of labial salivary glands consisted of T-cell components, which could induce the activation of autoreactive B cells (7). Although it remains unclear which clusters of CD4 or CD8 T cells play a role in SS pathogenesis, T-cell invasion could trigger the 164 Scand J Rheumatol 2019;48:164–165