#2460 Haemodialysis-related periarticular calcifications as cause of recurrent severe inflammatory state
Authors: Timsans Janis , Vilpakka Mari , Lusila Niilo , Kauppi Markku 
Published: May 2024

Abstract

Background and Aims
End stage chronic kidney disease (CKD) and haemodialysis (HD) are associated with disturbances in mineral and bone turnover ultimately leading to chronic kidney disease–mineral and bone disorder (CKD-MBD), which affects more than 90 % of patients with stage 5D CKD. The primary changes observed in CKD–MBD involve elevated phosphorus levels, decreased calcium levels, insufficient serum vitamin D, and heightened release of parathyroid hormone from the parathyroid glands, leading to secondary hyperparathyroidism. CKD-MBD leads to vascular calcification, increasing cardiovascular risk. There is also a correlation between abnormal bone remodeling activity in CKD-MBD and the likelihood of calcification in soft tissues. In rare instances, profound calcification occurs in periarticular tissues, resulting in severe inflammation and manifesting as systemic disease with articular involvement clinically.
The objective of this case report is to demonstrate a recurrent inflammatory condition caused by severe periarticular calcification in a patient on HD.

Case report
We present a case of a middle-aged white male diagnosed with hypertension, hypercholesterolemia, chronic obstructive pulmonary disease, hepatitis C, and end-stage renal disease caused by hydronephrosis. He was undergoing HD since July 2020.
From summer 2021 the patient experienced recurrent fever and arthralgias in the hips, elbows, and shoulders. Frequent acute hospitalizations were needed due to recurring fevers and severe inflammatory response with markedly elevated acute phase reactants (CRP was repeatedly &gt;200 mg/l), raising suspicion of infection. Laboratory and imaging tests however showed no clear signs of infection, and antibiotic therapy was ineffective.
An x-ray of the right AC-joint showed multiple periarticular calcifications dorsally from the AC-joint. Later, due to severe pain and swelling an MRI-scan of right elbow joint was conducted, revealing an osteomyelitis-suspect finding of the olecranon, and olecranon bursitis. No bacteria were detected in the punctate of olecranon bursa. X-ray scans of the elbows revealed bilateral soft tissue calcification dorsally from the proximal ulna. The x-ray scan of the right shoulder revealed calcific expansion in the AC-joint area, leading to total destruction of the lateral part of the clavicle. MRI and CT scans showed severe periarticular calcification around AC- and glenohumeral joints without inflammatory involvement of the synovium. Bony erosions were observed due to the pressure of calcified tissue on the bone. Whole-body CT-scan showed no sites of infection but there was a periarticular calcification observed around the hip joints.
A PET-CT scan of the whole body, neck, and upper extremities revealed no signs of malignancy or infections, but there was an increased uptake of 18F-fluorodeoxyglucose detected in several periarticular sites, indicating a multi-site inflammatory process resulting from severe periarticular calcifications. A dual-energy CT-scan of upper extremities was performed, excluding the accumulation of monosodium urate crystals.
The cycle of multiple hospitalizations and antibacterial therapies was broken with the diagnosis of CKD and HD-related inflammatory periarticular calcification. Initially, the inflammation was addressed with high-dose glucocorticoids. However, the dose was successfully tapered during the first month of treatment, and the patient continued to do well on a maintenance dose of 5 mg/day of prednisolone. Subsequently, hospitalizations, antibiotics, or surgical procedures were no longer required.

Conclusion
Severe CKD and HD cause disturbances in mineral and bone metabolism, that can lead to periarticular calcification. Like in our presented case, multi-site calcifications may mimic infection or autoimmune rheumatoid conditions making the way to correct diagnosis cumbersome and costly. Imaging techniques help us distinguish periarticular deposits from inflammatory and infectious arthritis. In our case low-dose prednisolone effectively reduced inflammation, obviating hospitalizations and minimizing healthcare burden.