900 - Statin-Associated Necrotizing Autoimmune Myopathy with rhabdomyolysis and functional decline

Statin-associated necrotizing autoimmune myopathy (SANAM) with rhabdomyolysis and severe proximal weakness causing functional decline.

Case Description:

A 54-y/o woman with HTN, T2DM, HLD (atorvastatin), and hepatitis developed progressive proximal weakness and fell with facial lacerations. CK was 25,900, aldolase 224, EMG/NCS showed proximal irritative myopathy, and HMG-CoA Ab IgG >200 confirmed SANAM. She received IVIG 2 g/kg and IV methylprednisolone ×5 days (8/20–8/24), then prednisone and methotrexate. Course was complicated by rhabdomyolysis, steroid-induced hyperglycemia, and transaminitis causing functional decline. Hyperglycemia was managed with insulin and metformin. CK and LFTs were monitored and down-trended.

Admitted to IPR on 8/29, she required mod assist for transfers, max assist for LE dressing, and ambulated 300–360 ft with roller walker and min assist. Ten-Meter Walk was 0.49 m/s (limited community ambulator). IPR emphasized strengthening, gait training, ADL retraining, caregiver education, and BP/DM optimization. On 9/5, before repeat IVIG planned for 9/8, PT documented 610 ft ambulation with contact-guard assist. She discharged home at supervision/min assist with outpatient therapy.

Discussions:

SANAM is rare and profoundly disables patients despite disease-modifying therapy. Immunotherapy halts immune-mediated injury, but restoration of participation requires simultaneous rehabilitation. This case shows safe coordination of infusion therapy within IPR alongside progressive mobility/ADL training and medical optimization (steroid-related HTN/hyperglycemia). Objective measures (10MWT, gait distance, assist levels) demonstrate functional responsiveness during the period spanning the second IVIG dose, suggesting that early, concurrent rehabilitation can amplify the benefits of immunotherapy and accelerate discharge readiness.

Conclusions:

In SANAM with rhabdomyolysis, early IPR integrated with ongoing immunotherapy improved mobility and ADL independence and enabled home discharge. PM&R is essential in neuromuscular autoimmune disease, bridging complex medical treatment with measurable functional recovery, and should be engaged at diagnosis rather than after decline.