Anti-AChR, MuSK, and LRP4 antibodies coexistence: A rare and distinct subtype of myasthenia gravis from Indian subcontinent

Background: Myasthenia gravis is B-cell mediated autoimmune disease and is associated with antibodies against the acetylcholine receptor (AChR), muscle-specific kinase (MuSK) and lipoprotein-related protein 4 (LRP4) in the postsynaptic membrane at the neuromuscular junction. There are few studies on the concurrent presence of two positive antibodies in the sera of patients with myasthenia gravis. Case description: A 32-year male admitted to the hospital with progressive neuromuscular weakness. He was diagnosed with Myasthenia gravis disorder mimicking Amyotrophic Lateral Sclerosis. We herein report a rare coexistence of three antibodies (anti-AChR, MuSK, and LRP4 antibodies) in the patient's serum. Conclusion: We present a detailed clinical and laboratory analysis of the patient. This case report will emphasize the importance of evaluating anti-MuSK and anti-LRP4 antibodies even in patients with anti-AChR antibodies.