The osteoarticular features of Gitelman Syndrome: Chondrocalcinosis and more

To characterize the clinical and radiographic osteoarticular features of patients with Gitelman Syndrome (GS) in a prospective Chinese cohort.

Patients with clinically and genetically diagnosed GS were prospectively and systematically screened for osteoarticular involvement. Clinical manifestations, laboratory parameters, and radiographic findings were recorded. Patients were categorized as: chondrocalcinosis, or calcium pyrophosphate deposition (CPPD), non-chondrocalcinosis osteoarticular abnormalities, and non-radiographic GS. Group differences were analyzed.

A total of 110 patients with GS were enrolled (mean age 39.90±13.70 years, 52.73% females), and 46 (41.82%) reported arthralgia. Radiographically, 46 patients (41.82%) were classified as CPPD, 15 (13.64%) showed non-chondrocalcinosis abnormalities, and 49 (44.54%) had no detectable osteoarticular involvement. CPPD patients were significantly older and had lower serum magnesium and estimated glomerular filtration rate (eGFR) compared with non-radiographic patients. Arthralgia occurred in 78.26% of CPPD cases. Knees were the most frequently involved joints in patients with CPPD, followed by cervical spine, Archilles tendon, hips, hands, shoulders, and wrists. Remarkably, non-chondrocalcinosis findings included dense bone islands and condensing osteitis of the sacroiliac joint.

CPPD presents in 41.82% of patients with GS. Low serum magnesium and decreased eGFR are risk factors for CPPD. In addition to chondrocalcinosis, GS may be associated with other osteoarticular manifestations, including dense bone islands and condensing osteitis.