MADSAM was first described by Lewis in 1982 and has rarely been described in association with sarcoidosis.

A 65-year-old gentleman presented with 3 months of ascending bilateral tingling, numbness and weakness as well as 35 pounds of weight loss. He developed left-sided distal lower extremity weakness that eventually involved the right lower extremity then both hands and arms. The patient reported a history of bilateral facial palsy 30 years ago. Examination showed asymmetrical weakness (3-4/5 on left, 4-5/5 on the right) of all extremities more distally than proximally with asymmetric wasting. Reflexes were reduced in left biceps, triceps and bilateral ankles and absent in bilateral knees. There was non-length dependent, patchy and asymmetrical decrease in sensations bilaterally. CSF analysis showed cell count of 22/µL (89% lymphocytes) and elevated protein of 127 mg/dL. MRI brain and spine were unremarkable. Electrodiagnostic studies revealed slowed conduction velocity and multifocal conduction block with active denervation predominantly on the left side consistent with acquired active chronic primary demyelination sensorimotor polyradiculoneuropathy. CT scan of the chest and abdomen revealed mediastinal lymphadenopathy. Lymph node histopathology showed non-caseating granulomas consistent with sarcoidosis. He responded well to intravenous immunoglobulins (IVIG) and oral steroids.

This case demonstrates the rare association between MADSAM and neurosarcoidosis based on the clinical, CSF, electrodiagnostic and lymph node biopsy findings. Treatment response to IVIg is 60-70% and to corticosteroid is 50-80% in MADSAM. In a prospective study of peripheral neurosarcoidosis, 12/14 (86%) of patients responded to corticosteroids. Our patient responded to IVIG and continued to improve on prednisone 60 mg daily that was started following lymph node biopsy. This case demonstrates the importance of thorough investigation looking for underlying etiology in patients with peripheral nervous system disorders.