A CASE OF SYSTEMIC LUPUS ERYTHEMATOSUS WITH SECONDARY AMYLOIDOSIS WITH FMF MUTATION AND MYASTHENIA GRAVIS

Background: The association of myasthenia gravis (MG) and systemic lupus erythematosus (SLE) is rare, although both of them are autoimmune diseases. Secondary amyloidosis (AA) may complicate the chronic inflamations or chronic infections but after SLE, it is also rare.Objectives: We present a rare association between SLE, MG and AA together here.Results: A 22 year-old boy, with SLE, developed secondary amyloidosis and myasthenia gravis after 10 years of follow-up, who had compound heterozygote FMF mutation. He was admitted to department of pediatrics with edema, pleuritis, hematuria, palpable purpuras on the lower extremities, arthritis of bilateral foot-ankle joints and oliguria, when he was 12 years old. In labaratory investigations; high levels of acut phase reactants, the decrease in the serum C3 level, trombocytopenia, anemia, hematuria, proteinuria and anti-ds DNA pozitivity were found. He was diagnosed as SLE with 4 positive diagnostic criteries: anti-ds DNA pozitivity, non-erozive arthritis, serositis (pleuritis and pericarditis), and renal involvement. The diagnosis was supported by renal biopsy which showed Type IV (membranoproliferative glomerulonephritis with 30% cresents) lupus nephritis and no amyloid depositis were seen with Congo red. He was treated with corticosteroids and cyclophospamide pulses within two years. Since the activity of SLE diminished, oral low dose prednisone withdrawn after 7 years. In the 10th year of follow-up, he had muscular weakness and severe fatigue with nephrotic proteinuria. Although, he was accepted to hospital for a probable activation of SLE, his renal biopsy showed AA type amyloid deposition with Congo red. Than, a molecular investigation was performed for Familial Mediterranean Fever (FMF) and the patient was found to have compound heterozygote mutation (M694V/V726A). Since he presented severe fatigue and muscular weakness he had investigated with EMG and myasthenia gravis diagnosis was achiewed. The tensillion test was also found positive. He was commenced on colchisin, mesthionone and prednisone.This case is interesting with a rare combination of SLE with AA amyloidosis and Myasthenia gravis with FMF genetic mutation at the same time. Secondary amyloidosis with rheumatic diseases is usual but association with SLE is rare and the prevalance is not clear. Thus, this case suggests that, if a lupic patient comes with nephrotic proteinuria, secondary amyloidosis must be thought in the differantial diagnosis. Secondly, this patient is also interesting with late onset of MG. In the literature, there are similar cases with late onset MG after SLE and vice versa. The pathogenesis of SLE after MG especially acoording to tymectomy but pathogenesis of late onset MG after SLE is not well-known and the cases were mainly woman in eldery ages.Conclusion: The amyloidosis developed in this patient, who presented a very well response to the aggressive initial therapy of lupus nephritis, may be secondary to SLE as well as FMF. Therefore, it is hard to declare the definite cause of the amyloidosis in this patient, that appears after 10 years of follow-up. We think that the case is interesting, since a patient with SLE developed MG associated with amyloidosis probably secondary to FMF or SLE.References: 1. Huston DP, McAdam KP, Balow JE, Bass R, DeLellis RA. Amyloidosis in systemic lupus erythematosus. Am J Med .1981 Feb; 70 (2): 320-3.2. Rosskamp R, Berdel D. Myasthenia gravis following lupus erythematosus disseminatus. Klin Padiatr. 1983 Nov-Dec; 195(6): 433-5Citation: Ann Rheum Dis, volume 64, supplement III, year 2005, page 506Session: Paediatric rheumatology