Case Presentation: A 73-year-old woman with a past medical history of hypertension and osteoarthritis presented to the emergency department with progressive right lower back pain after a mechanical fall, subacute oropharyngeal dysphagia, and diffuse proximal and distal muscle weakness. On presentation, she was afebrile with unremarkable vital signs. Her labs were significant for a WBC of 14,500 K/uL, elevated ESR of 32 mm, and CRP of 11.2 mg/dL. Creatinine phosphokinase levels were mildly elevated at 492 UI/L. MRI total spine was negative for spinal cord compression. High sensitivity troponins were elevated to 817 and uptrended to 1,050 pg/mL. ECG showed a normal sinus rhythm without ischemic findings. A cardiac MRI was performed and was negative for myocarditis. Modified barium swallow showed generalized weakness of her oropharyngeal muscles. Following admission, the patient’s calcium levels steadily increased from 10.6 on admission to 12.1 mg/dL. 1,25-hydroxyvitamin D was greater than the detectable limit and ACE levels were elevated at 92 IU/L. A PET/CT was performed to evaluate for potential neoplastic malignancies, and although there were no signs of cancer, there was significant uptake diffusely throughout her musculature, without any noted lymphadenopathy. This indicated a diffuse myositis process. A muscle biopsy confirmed the presence of non-caseating granulomas. An extensive workup including TB, HIV, endemic fungal infections, hepatitis panel, Q fever, blood cultures, RPR, and rheumatologic markers such as ANA, ANCA, cryoglobulins, AMA, and an ENA panel were all negative. The patient’s presentation was felt to be most consistent with idiopathic granulomatous myositis. The patient was started on IV solumedrol and endorsed immediate relief of symptoms, with improvements in muscle strength throughout her upper and lower extremities. The patient was discharged on oral prednisone and was feeling well at a 1-month telephone follow up.
Discussion: Idiopathic granulomatous myositis (IGM) presents with a clinical syndrome of asymmetric distal muscle weakness associated with the presence of granulomas on muscle biopsy. Our patient presented with diffuse muscle weakness involving her oropharyngeal muscles, and proximal and distal skeletal muscles. She also had hypercalcemia related to elevated levels of 1,25-hydroxyvitamin D. This is consistent with a granulomatous process. Etiologies of granulomatous myositis include sarcoidosis, cryofibrinogenemia, primary biliary cirrhosis, inflammatory bowel disease, thymoma myasthenia gravis, and lymphoma. Also, infectious etiologies, such as tuberculosis, syphilis, histoplasmosis, pneumocystis jirovecii, brucellosis, HTLV1, and cryptococcus may present with granulomatous disease. First-line in management is systemic corticosteroids after infectious etiologies have been ruled out.
Conclusions: We report this case to heighten the awareness of granulomatous myositis, a rare disease that is characterized by non-caseating granulomas of the skeletal muscles. Granulomatous myositis is most commonly either secondary to sarcoidosis or idiopathic, although the differential is quite broad, including infectious, autoimmune, and malignant etiologies, necessitating an extensive workup before the initiation of treatment. Initial management of idiopathic granulomatous myositis is systemic corticosteroids.