Rheumatoid Arthritis Associated With Anti-Signal Recognition Particle Immune-Mediated Necrotizing Myopathy: A Case Report

Immune-mediated necrotizing myopathy (IMNM) is a rare subtype of idiopathic inflammatory myopathy that is characterized by severe subacute proximal weakness, myofiber necrosis, and significantly elevated serum creatine kinase. Anti-signal recognition particle (SRP) and anti-3-hydroxy-3-methylglutaryl-coenzyme-A reductase autoantibodies have been found in about two-thirds of patients with IMNM. This myopathy is usually idiopathic and there is a scarce literature concerning its association with connective tissue diseases. Herein, we report an unusual case of a young woman who presented with both rheumatoid arthritis and severe anti-SRP IMNM. Thankfully to a therapeutic protocol combining rituximab and cyclophosphamide, an important improvement was achieved, and notably no serious side effect was observed.

Severe Headache, Paraesthesias, Facial Diplegia and Pleocytosis: A Misleading Presentation of Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy. Progressive limb weakness, diminished/absent reflexes, sensory disturbance, and variable autonomic dysfunction are its core clinical manifestations. Bifacial weakness with paraesthesias (BFP) is a rare regional variant of GBS and is characterized by simultaneous facial diplegia, distal paraesthesias and minimal or no motor weakness. The association of headache with classic GBS has been rarely reported in the literature, and has not yet been described in the BFP variant. Here we report a misleading case of BFP variant associated with severe headache and mild pleocytosis. The repetition of nerve conduction studies (NCS) was extremely beneficial in this confusing case.

LEARNING POINTS

Bifacial weakness with paraesthesias (BFP) is a rare regional subtype of classic Guillain-Barré syndrome.Severe headache can be a symptom of the BFP variant.The association of headache, BFP and pleocytosis can be confusing, particularly if initial nerve conduction studies are unrevealing.

Skeletal Myopathy as the Initial Manifestation of Light Chain Multiple Myeloma

Monoclonal gammopathies due to plasma cell dyscrasias can cause various rare neuromuscular disorders. The peripheral nervous system is most commonly affected, while muscle diseases associated with monoclonal gammopathies are rare. Skeletal myopathy, as a manifestation in the context of multiple myeloma, is extremely uncommon and is usually the result of immunoglobulin light chain (AL) amyloidosis deposits in the muscles. Here we present an atypical case of a patient with generalized myopathy as the presenting manifestation of light chain multiple myeloma. Interestingly, muscle involvement in our case was not the consequence of AL amyloidosis deposits but rather due to non-amyloid light chain deposition disease associated with light chain multiple myeloma.

LEARNING POINTS

Light chain multiple myeloma can present as myopathy.Creatine kinase and muscle biopsy specimens only examined using routine stains can be normal in this condition.

Novel SOST gene mutation in a sclerosteosis patient from Morocco: a case report

Sclerosteosis (OMIM 269500) is a rare autosomal recessive condition characterized by increased bone density associated with syndactyly. It is linked to a genetic defect in the SOST gene coding for sclerostin. So far, seven different loss-of-function mutations in SOST have been reported in patients with sclerosteosis. Recently, two mutations in LRP4 gene underlying sclerosteosis were identified, reflecting the genetic heterogeneity of this disease. We report here a 30-years-old Moroccan man presented with typical clinical and radiological features of sclerosteosis who carries a novel homozygous mutation in the SOST gene, characterized as a nonsense mutation (c.79C > T; p.Gln27∗) in exon 1 of the SOST gene. This is to our knowledge the first case of sclerosteosis reported from Morocco and North Africa.