We report the case of a 13 year-old, Hispanic girl who was diagnosed with JDM-SLE overlap syndrome at age 10. She initially presented to our hospital with complaints of symmetric upper and lower extremity muscle weakness and a photosensitive rash for 1 week prior to presentation. On physical examination, she had 3/5 strength in the proximal muscles of the bilateral upper and lower extremities, with an initial CMAS score of 6. Her cutaneous manifestations included a malar rash, heliotrope rash, and violaceous plaques on the dorsal aspect of the metacarpophalangeal joints consistent with Gottron papules. Her initial laboratory examination was significant for elevated muscle enzymes with an AST of 611, ALT of 392, alkaline phosphatase of 118, LDH of 1740, and creatine kinase of 16,012. She subsequently had a lower extremity MRI performed that showed diffuse, symmetric intramuscular T2 hyper intense signal within the gluteal adductor, extensor, and flexor musculature, consistent with diffuse proximal lower extremity myositis. On further laboratory examination, she was found to have a strongly positive ANA of 1:1280 with speckled pattern and a positive dsDNA by Crithidia of 19 (strongly positive > 9), with normal complements and negative Smith/RNP antibodies. With her clinical findings, laboratory evaluation, and radiologic findings she was diagnosed with a likely overlap syndrome with mostly features of JDM and SLE. As an inpatient, she was started on “protocol A” based on the “three consensus protocols for the initial treatment of moderate to severe juvenile dermatomyositis” [10]. She received IV methylprednisolone 30 mg/kg/day for 3 days and was started on subcutaneous methotrexate 15 mg/m^2 weekly. She was also started on oral hydroxychloroquine 200 mg/day, and after 3 days of methylprednisolone she was transitioned to oral prednisone 2 mg/kg/day divided BID. After the high dose steroids, her CK decreased to 5756 and her muscle strength improved as per PT evaluation, and she was discharged home 1 week after admission.
As an outpatient, she was scheduled to receive aggressive physical therapy. However, shortly after being discharged home she had two episodes of falling due to weakness and was readmitted 2 weeks after her initial presentation. She was found to have worsening proximal muscle strength at 2/5 in the lower extremities, a return of her photosensitive rash, and an increase in her CK to 8784. At this point she was switched to “Protocol B” of the above mentioned treatment recommendations and was given IVIG 2G/kg [10]. Given the severity of her weakness and her typical photosensitive rash, she was given another course of IV methylprednisolone 30 mg/kg/day for 3 days. She was then transferred to the inpatient rehabilitation unit where she completed 1 week of aggressive daily physical and occupational therapy. She was maintained on monthly IVIG and subcutaneous methotrexate along with a daily oral tapered prednisone regimen. She had another flare 11 months after her initial diagnosis which presented as a new inflammatory synovitis in the knee and wrist. She also had return of her malar rash, a worsening rash over her bilateral shoulders and chest (shawl sign), and elevation of her CK to 12,461, likely secondary to noncompliance with her outpatient IVIG infusions. She again received IV methylprednisolone 30 mg/kg/day for 3 days and IVIG 2G/kg. After discharge, despite better compliance with her monthly IVIG infusions, she continued to have episodes of weakness and elevated muscle enzymes with difficulty weaning off of prednisone. At 16 months after initial diagnosis, she was given two doses of Rituximab 750 mg/m^2 intravenous infusions for recalcitrant disease, and was maintained on IVIG 70 g every month. Two months after completion of her Rituximab course there was drastic improvement and eventually normalization of her serological muscle enzymes.
At 22 months after diagnosis, she continued to complain of pain in her lower extremities despite receiving monthly IVIG and intense ongoing physical therapy. During an outpatient physical examination at this time, she was very hesitant to sit on the floor, and had to use Gower’s maneuver to stand from sitting. There was also new, decreased passive range of motion of the right hip when compared to the left. Estimated CMAS score at this time was improved to 47. Her muscle enzymes were also now persistently normal, so it was unclear if this was anatomical versus isolated muscle group weakness. Due to her continued symptoms and asymmetrical findings, an x-ray of the pelvis was ordered, which showed a rounded ossification near the right femoral neck, a smaller ossification near the left medial acetabulum, and multiple muscular calcifications in the adductor groups near the hip. A CT scan of the pelvis was ordered to further evaluate these findings, which showed a region of bulky, dense, soft tissue calcification measuring 3.8 × 2.3 cm within the ischiofemoral region on the right (Figs. 1 and 2), as well as scattered coarse linear calcifications within the abductor muscles bilaterally (Fig. 3). It also showed a 5.0 × 1.0 cm ovoid calcification in the left obturator internus muscle near the ischium. It was felt that these calcifications were contributing to her limitations in range of motion and subjective complaints, so additional therapy was pursued. She was started on the bisphosphonate alendronate orally at 10 mg/day in addition to her ongoing therapy with hydroxychloroquine, weekly methotrexate, and monthly IVIG.
Our patient continued to follow up every 3 months in our clinic. Three months after starting alendronate she reported some improvement in her pain and strength, but on physical examination still had difficulty with squatting, and still used Gower’s maneuver when standing. A repeat x-ray was ordered at 7 months on bisphosphonate therapy, which showed complete resolution of previously seen calcified lesions. At her next follow up visit, after being on bisphosphonates for 10 months, she no longer had to use Gower’s maneuver with standing, and had equal range of motion in her bilateral lower extremities. A repeat CT scan was performed 11 months after therapy, which, similar to the x-ray, showed complete resolution of the previously seen soft tissue calcifications (Figs. 4 and 5). With complete resolution of the calcinosis, her alendronate was discontinued at her next follow-up visit. Throughout the duration of treatment, she did not report any of the short-term side effects such as GI irritation or new bone pain related to her bisphosphonate therapy.
