The association of systemic lupus erythematosus and myasthenia gravis: a series of 17 cases, with a special focus on hydroxychloroquine use and a review of the literature

Abstract

The coexistence of systemic lupus erythematosus (SLE) and myasthenia gravis (MG) is rarely reported, and most of the published studies are case reports. Hydroxychloroquine, an antimalarial agent, is an essential treatment in patients with SLE but special caution is recommended when used in MG patients. We retrospectively analyzed the clinical features, laboratory findings, and outcome of 17 patients with both diseases with a special focus regarding hydroxychloroquine use and with a review of the literature. All patients were women. The mean age at MG onset and SLE diagnosis was 34.5 [14-64] and 37.8 [18-72] years, respectively. The presenting symptoms of MG were limb weakness (94%), ocular (88%) and bulbar involvement (53%). Autoantibodies against the acetylcholine receptor were positive in 94% of cases. The main manifestations of SLE included arthritis (88%), cytopenias (53%) and skin rash (41%). Treatment of SLE required hydroxychloroquine (94%), steroids (47%) and immunosuppressive drugs (18%). Among eight patients (47%) who developed MG after initiation of hydroxychloroquine, the question of induction of MG by hydroxychloroquine was raised in one patient. On the other hand, an exacerbation of myasthenic symptoms was only seen in one of the eight patients who received hydroxychloroquine after the diagnosis of MG. Including our cases, we reviewed a total of 70 patients with SLE and MG. Compared with a large series of 1,000 unselected SLE patients, those with associated MG were older, had lower incidence of cutaneous, renal, and neurological manifestations, and higher frequency of anticardiolipin antibodies and lupus anticoagulant. In conclusion, the clinical pattern of patients with SLE and MG seems to be characterized by a less severe course of SLE and higher frequency of antiphospholipid antibodies. Hydroxychloroquine treatment appears to be safe in this setting.

The Course of Myasthenia Gravis with Systemic Lupus Erythematosus

“…Previous reports suggested that in a majority of the patients, MG preceded SLE [5]. Our patients had SLE when the MG diagnosis was made except one patient who had lupus-like symptoms without fulfilling the diagnostic criteria before MG onset.…”

“…Jallouli et al reported the co-occurrence of MG with SLE in 17 patients; they did not comment on the course of MG [5]. We would like to underline that all of our patients had generalized MG and four of five patients experienced at least one myasthenic crisis.…”

“…Systemic lupus erythematosus is one of the autoimmune diseases, which is rarely reported with MG [5,6,7]. In the limited number of reports, the clinical features of MG in patients with MG and SLE were not mentioned in detail.…”

Frequency of familial occurrence and associated autoimmune diseases in a cohort of patients with acquired autoimmune myasthenia gravis from Belgrade

“…Među pacijentima obuhvaćenim našom studijom, autoimune bolesti koje su se najčešće javljale udružene sa MG bile su Hašimoto tireoiditis, SLE, polimiozitis, RA i perniciozna anemija, što je u skladu sa nalazima drugih studija (9,15,23,25,26). Učestalost Hašimoto tireoiditisa iznosila je 4%, a skoro isti podatak (4,2%), dobijen je u studiji sprovedenoj u Japanu na 142 pacijenta sa MG (24).…”

“…Učestalost Hašimoto tireoiditisa iznosila je 4%, a skoro isti podatak (4,2%), dobijen je u studiji sprovedenoj u Japanu na 142 pacijenta sa MG (24). Zapažene učestalosti SLE u literaturi variraju od 1 do 8%, što je u skladu sa našim rezultatom od 1,3%, dok je učestalost udruženog javljanja RA u našoj studiji bila manja u odnosu na podatke iz drugih studija (0,9% naspram 4%) (9,15,23,25,26). Suzuki i saradnici (27) zabeležili su učestalost polimiozitisa od 0,65%, što je približno vrednosti od 0,9%, dobijenoj u našoj studiji.…”