Asymptomatic secondary hyperparathyroidism can mimic sacroiliitis on computed tomography

Area of Science:

• Radiology
• Nephrology
• Rheumatology

Background:

• Secondary hyperparathyroidism (sHPT) is a common complication of chronic kidney disease (CKD).
• sHPT has been associated with sacroiliac joint (SIJ) manifestations.
• The specific SIJ changes in asymptomatic sHPT patients require systematic evaluation.

Purpose of the Study:

• To systematically assess SIJ changes in patients with asymptomatic sHPT using high-resolution computed tomography (CT).
• To compare the prevalence and characteristics of SIJ lesions between patients with asymptomatic sHPT and controls without SIJ disease.

Main Methods:

• Retrospective case-control study including 56 patients with asymptomatic sHPT and 259 matched controls.
• High-resolution CT datasets were analyzed using a structured scoring system for erosions, sclerosis, osteophytes, joint space alterations, and intraarticular calcifications.
• Chi-squared tests were employed to compare lesion frequencies between groups.

Main Results:

• Erosions were significantly more prevalent in the iliac portions of the SIJ in patients with sHPT (ventral: 28.6% vs. 13.9%; middle: 17.9% vs. 7.7%).
• Partial or complete ankylosis was rare and not significantly different between groups.
• No significant differences were observed in the prevalence or extent of sclerosis or calcifications between the sHPT and control groups.

Conclusions:

• Joint lesions resembling sacroiliitis are present in a notable proportion of asymptomatic patients with sHPT.
• These findings suggest a potential link between sHPT and SIJ pathology, even in the absence of symptoms.
• Further research is warranted to determine the clinical significance of these CT-detected SIJ changes in sHPT.