A white Swiss man presented with painful arm cramps and a history of symptoms over a period of 3 years. In the initial clinical investigation, the 52-year-old carpenter also showed edema in both legs, without any other complaints. In his personal history, the patient had a history of a seronegative non-tropical sprue as well as a history of several orthopedic procedures including total hip arthroplasty.
A physical examination revealed full and painless range of motion of all joints of the upper and lower extremities with normal muscle strength. His serum human leukocyte antigen-B27 (HLA-B27) result was positive and his urine acid was mildly elevated (467 U/l). Other screening laboratory examinations, such as antinuclear antibodies (ANA), anti-dsDNA antibodies, rheumatoid factor (RF), anti-citrullinated peptide antibodies (anti-CCP), serology for borreliosis and thyroid-stimulating hormone (TSH), were negative.
Radiographs of his hands and feet and a chest radiograph remained unremarkable. An initial MRI scan of both hands showed a diffuse contrast enhancement of the palmar aponeurosis and muscles (Figure 1). His joints and bones did not show any pathological changes.
A magnetic resonance imaging examination of his right hand at initial presentation. T1-weighted fat-saturated axial magnetic resonance image shows diffuse enhancement of the muscles and the palmar aponeurosis (arrow). There are no pathological features in his bones or joints
An empiric therapy was started with prednisolone 20 mg for 10 days and 10 mg daily for an additional 6 weeks. Our patient showed complete resolution of pain complaints after 6 weeks and therapy was discontinued. A follow-up consultation was planned after 6 months and cancelled by the asymptomatic patient.
One year after the first presentation, our patient presented again to our hospital with reduced general health and a diffused weakness of his extremities. In addition to recurrent pain in his arms and hands, our patient also showed a new symptom – weakness and pain in his upper and lower legs.
Due to these generalized symptoms and lack of diagnostic evidence, a whole-body PET-CT scan was performed. A diffused uptake of fludeoxyglucose (FDG) was found in all skeletal muscles of his legs and arms without involvement of his lungs or lymph nodes (Figure 2 and Figure 3). Furthermore, various other muscles of his chest and body showed unspecific FDG uptake (Figure 3). Unspecific myositis was suspected at this point. In order to confirm the diagnosis, a transcutaneous muscle biopsy was performed in the quadriceps muscle of his right leg. The biopsy of the affected muscles showed granulomatous myositis.
A positron emission tomography/computed tomography examination of the upper thighs 1 year after initial presentation. An axial positron emission tomography/computed tomography image demarks diffuse bilateral distribution of spots with increased fludeoxyglucose uptake of all muscles of the upper thighs
Coronal reconstruction of a positron emission tomography/computed tomography examination shows increased fludeoxyglucose uptake with diffuse involvement of the muscles of the extremities and the trunk
Based on the diagnosis of sarcoidosis of the skeletal muscle, a therapy with prednisolone 50 mg/day was started again. This therapy reduced the muscle complaints immediately. In order to preserve the good clinical condition of our patient, a weekly, supporting therapy with methotrexate (20 mg) and folic acid (5 mg) was established and administration of prednisolone was tapered. After 1 year, our patient was symptom-free and was able to work without any restrictions. No further imaging was performed due to the positive clinical outcome.
J Med Case Reports. 2017;11(246) © 2017 BioMed Central, Ltd.