Browsing by Subject "renal calculi"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Clinical and Metabolic Correlates of Pure Stone Subtypes
    (Liebert, 2021) Brinkman, John E.; Large, Tim; Nottingham, Charles U.; Stoughton, Christa; Krambeck, Amy E.; Urology, School of Medicine
    Background: There are multiple stone types, each forming under different urinary conditions. We compared clinical and metabolic findings in pure stone formers to understand if there are consistent factors that differentiate these groups in terms of underlying etiology and potential for empiric treatment. Materials and Methods: Pure SFs based on infrared spectroscopic analysis of stones obtained at our institution between 01/2002 and 07/2018 with a corresponding 24-hour urinalysis were retrospectively evaluated. Results: 121 apatite, 54 brushite, 50 calcium oxalate dihydrate, 104 calcium oxalate monohydrate, and 82 uric acid patients were analyzed. Apatite, brushite, and calcium oxalate dihydrate patients were younger than calcium oxalate monohydrate and uric acid patients. Uric acid patients had the highest male predominance (76.8%), while apatite patients were predominantly female (80.2%). Uric acid was most associated with diabetes mellitus (45.3%), and calcium oxalate monohydrate with cardiovascular disease (27.2%) and malabsorptive gastrointestinal conditions (19.2%). Brushite patients had the highest prevalence of primary hyperparathyroidism (17%). Apatite, brushite, and calcium oxalate dihydrate patients demonstrated high rates of hypercalciuria (66.1%, 79.6%, 82%). Apatite and brushite patients had the highest urinary pH. Apatite patients exhibited the highest rate of hypocitraturia while calcium oxalate dihydrate patients exhibited the lowest (55.4%, 30%). Calcium oxalate monohydrate patients had the highest rate of hyperoxaluria (51.9%). Uric acid patients had the lowest urinary pH. There were no observable differences in the rates of hyperuricosuria or hypernatriuria. Conclusions: These results demonstrate that pure stone composition correlates with certain urinary and clinical characteristics. This data can help guide empiric clinical decision-making.
  • Thumbnail Image
    Item
    Sensitivity of Non-Contrast Computed Tomography for Small Renal Calculi with Endoscopy as the Gold Standard
    (Elsevier, 2018) Bhojani, Naeem; Paonessa, Jessica E.; El Tayeb, Marawan M.; Williams, James C.; Hameed, Tariq A.; Lingeman, James E.; Urology, School of Medicine
    Objectives To compare the sensitivity of non-contrast CT to endoscopy for detection of renal calculi. Imaging modalities for detection of nephrolithiasis have centered on abdominal x-ray (KUB), ultrasound (US), and non-contrast computed tomography (CT). Sensitivities of 58-62% (KUB), 45% (US), and 95-100% (CT) have been previously reported. However, these results have never been correlated with endoscopic findings. Methods Idiopathic calcium oxalate stone formers with symptomatic calculi requiring ureteroscopy (URS) were studied. At the time of surgery, the number and location of all calculi within the kidney were recorded followed by basket retrieval. Each calculus was measured and sent for micro CT and infrared spectrophotometry. All CT scans were reviewed by the same genitourinary radiologist who was blinded to the endoscopic findings. The radiologist reported on the number, location, and size of each calculus. Results 18 renal units were studied in 11 patients. Average time from CT scan to URS was 28.6 days. The mean number of calculi identified per kidney was 9.2±6.1 for endoscopy and 5.9±4.1 for CT (p<0.004). The mean size of total renal calculi (sum of longest stone diameters) per kidney was 22.4±17.1 mm and 18.2±13.2 mm for endoscopy and CT, respectively (p=0.06). Conclusions CT scan underreports the number of renal calculi, probably missing some small stones and unable to distinguish those lying in close proximity to one another. However, the total stone burden seen by CT is, on average, accurate when compared to that found on endoscopic examination.