“Silent” kidney stones in “asymptomatic” primary hyperparathyroidism—a comparison of multidetector computed tomography and ultrasound

Abstract

PurposeThe purpose of this study was to demonstrate the high number of kidney stones in primary hyperparathyroidism (PHPT) and the low number of in fact “asymptomatic” patients.MethodsForty patients with PHPT (28 female, 12 male; median age 58 (range 33–80) years; interquartile range 17 years [51–68]) without known symptoms of kidney stones prospectively underwent multidetector computed tomography (MDCT) and ultrasound (US) examinations of the urinary tract prior to parathyroid surgery. Images were evaluated for the presence and absence of stones, as well as for the number of stones and sizes in the long axis. The MDCT and US examinations were interpreted by two experienced radiologists who were blinded to all clinical and biochemical data. Statistical analysis was performed using the Wilcoxon signed-rank test.ResultsUS revealed a total of 4 kidney stones in 4 (10 %) of 40 patients (median size 6.5 mm, interquartile range 11.5 mm). MDCT showed a total of 41 stones (median size was 3 mm, interquartile range 2.25 mm) in 15 (38 %) of 40 patients. The number of kidney stones detected with MDCT was significantly higher compared to US (p = 0.00124).ConclusionsMDCT is a highly sensitive method for the detection of “silent” kidney stones in patients with PHPT. By widely applying this method, the number of asymptomatic courses of PHPT may be substantially reduced. MDCT should be used primarily to detect kidney stones in PHPT and to exclude asymptomatic PHPT.

Subclinical urolithiasis in patients with asymptomatic primary hyperparathyroidism

“…16,17 The best method for diagnosing renal tract stones remains debatable but CT scans appear to be more sensitive as evident from our and other studies. 18,19 In our series, biochemical parameters did not differ significantly between 'stone formers' and 'nonstone formers' although other authors have demonstrated a higher risk of stone formation in patients with high urinary calcium levels. 15,20 Cassibba and colleagues, 21 showed that in patients with PHPT, overt nephrolithiasis is associated with higher levels of serum calcium and PTH confirming the role of PHPT as a risk factor with further suggestions that silent nephrolithiasis helps to identify a more active and severe form of disease and these patients meet surgical indication more frequently than PHPT without stone disease.…”

Occult urolithiasis in asymptomatic primary hyperparathyroidism

“…Several recent studies suggest that the prevalence of occult urolithiasis ranges from 7–36% as assessed by ultrasound. 11,12,30,45,46 Rates may be higher when CT is used because ultrasound can miss small stones. 46 Most of our patients had renal ultrasound rather than abdominal CT.…”

“…11,12,30,45,46 Rates may be higher when CT is used because ultrasound can miss small stones. 46 Most of our patients had renal ultrasound rather than abdominal CT. The higher prevalence of stones in the group screened with CT suggests that the prevalence of occult renal stones could be underestimated by this study.…”

Primärer Hyperparathyreoidismus

“…Die klassische Symptomtrias "Stein-, Bein-und Magenpein" in Anspielung auf vermehrte Nierensteinbildung, erhöhte Knochendemineralisierung und Entzündungen der Magenschleimhaut ist seltener geworden. Bei genaueren klinischen Untersuchungen konnten allerdings gehäuft Nierensteine und beeinträchtigte Muskelfunktionen beobachtet werden [3,4].…”