Objectives This study investigates nephrolithiasis frequency in Ankylosing spondylitis (AS) patients compared to general population. Additionally, longitudinally assessing changes in renal CT abnormalities, it seeks to provide radiological evidence for early diagnosis of nephrolithiasis in AS patients. Methods In this retrospective study, 115 patients fulfilling the Modified New York Criteria for AS and 115 age- and sex-matched healthy controls were included. Renal ultrasound and/or CT imaging were carried out to evaluate presence of nephrolithiasis. Participants were categorized into three groups based upon imaging outcomes: Nephrolithiasis Group, Renal Medullary Hyperattenuation (RMH) Group, and Renal-Negative Group. AS patients were further stratified by disease duration (≤ 5 years, 5–10 years, > 10 years) and age (≤ 30, 30–40, 40–50, 50–60, 60–80 years). Longitudinal follow-up of renal CT abnormalities was conducted in 15 AS patients, with changes classified as positive (progression) or negative (regression). Results Among AS patients, 40% (46/115) were diagnosed with nephrolithiasis, and 19.13% (22/115) exhibited RMH. In contrast, only 12.17% (14/115) of controls had nephrolithiasis, and 9.57% (11/115) showed RMH. AS patients had a significantly higher nephrolithiasis frequency (P < 0.001) and RMH (P < 0.05) compared to controls. Patients with disease duration > 10 years had a 3.01-fold higher risk of nephrolithiasis than those with a duration ≤ 5 years (P < 0.05). Male AS patients had a 3.17-fold higher risk of nephrolithiasis than females (P > 0.05). Although odds ratio (OR) for nephrolithiasis increased progressively with age in groups ≤ 60 years, no statistically significant disparities were observed among age groups. Notably, the OR for the 60 < age ≤ 80 group exceeded that of 30 < age ≤ 40 group but was lower than those of the 40 < age ≤ 50 and 50 < age ≤ 60 groups. Longitudinal follow-up revealed positive changes in renal CT abnormalities in 13 of 15 AS patients. Conclusions The frequency of nephrolithiasis and RMH is significantly higher in AS patients compared to general population, particularly in those with a longer disease duration. RMH might act as an early radiological indicator of nephrolithiasis in AS patients, highlighting importance of regular renal imaging for early detection and management.

Ankylosing spondylitis: an independent risk factor for nephrolithiasis and the prognostic value of follow-up CT

期刊论文
发表日期：

2026年1月20日

查看全文

Zheng Yue,
Min Zhou,
Yue Hu,
Yuhui Wang

摘要

Objectives

This study investigates nephrolithiasis frequency in Ankylosing spondylitis (AS) patients compared to general population. Additionally, longitudinally assessing changes in renal CT abnormalities, it seeks to provide radiological evidence for early diagnosis of nephrolithiasis in AS patients.

Methods

In this retrospective study, 115 patients fulfilling the Modified New York Criteria for AS and 115 age- and sex-matched healthy controls were included. Renal ultrasound and/or CT imaging were carried out to evaluate presence of nephrolithiasis. Participants were categorized into three groups based upon imaging outcomes: Nephrolithiasis Group, Renal Medullary Hyperattenuation (RMH) Group, and Renal-Negative Group. AS patients were further stratified by disease duration (≤ 5 years, 5–10 years, > 10 years) and age (≤ 30, 30–40, 40–50, 50–60, 60–80 years). Longitudinal follow-up of renal CT abnormalities was conducted in 15 AS patients, with changes classified as positive (progression) or negative (regression).

Results

Among AS patients, 40% (46/115) were diagnosed with nephrolithiasis, and 19.13% (22/115) exhibited RMH. In contrast, only 12.17% (14/115) of controls had nephrolithiasis, and 9.57% (11/115) showed RMH. AS patients had a significantly higher nephrolithiasis frequency (P < 0.001) and RMH (P < 0.05) compared to controls. Patients with disease duration > 10 years had a 3.01-fold higher risk of nephrolithiasis than those with a duration ≤ 5 years (P < 0.05). Male AS patients had a 3.17-fold higher risk of nephrolithiasis than females (P > 0.05). Although odds ratio (OR) for nephrolithiasis increased progressively with age in groups ≤ 60 years, no statistically significant disparities were observed among age groups. Notably, the OR for the 60 < age ≤ 80 group exceeded that of 30 < age ≤ 40 group but was lower than those of the 40 < age ≤ 50 and 50 < age ≤ 60 groups. Longitudinal follow-up revealed positive changes in renal CT abnormalities in 13 of 15 AS patients.

Conclusions

The frequency of nephrolithiasis and RMH is significantly higher in AS patients compared to general population, particularly in those with a longer disease duration. RMH might act as an early radiological indicator of nephrolithiasis in AS patients, highlighting importance of regular renal imaging for early detection and management.