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Stone Patients (stone + patient)
Selected AbstractsAnalysis of bone mineral density in urolithiasis patientsINTERNATIONAL JOURNAL OF UROLOGY, Issue 4 2005HIDENORI TSUJI Abstract Background:, The association between hypercalciuria and bone mineral density (BMD) has been already recognized. The aim of the present study is to relate BMD to age and sex and to evaluate the calcium metabolism and hypercalciuria-defined dietary or non-dietary category in patients with urolithiasis. Methods:, The BMI of the L2,L4 lumbar vertebrae was measured in 310 renal stone patients (191 men and 119 women). Percent age matched score (%AMS), which is the percent ratio of measured BMD to the mean BMD of age-matched control subjects, was utilized for the appraisal of BMD. Low BMD groups were defined by lower than 90% of %AMS. Results:, Low BMD was observed in 27.7% of urinary stone patients, which was not a significant difference to that of control subjects (23.5%) who were measured in the health examination. In male patients with urolithiasis, the frequency of patients in whom BMD had been apt to decrease since youth was high, but there was not a proven significant difference among the three age groups (20,39 years old, 40,59 years old and 60 years old or older). In contrast, for female stone patients, the frequency of low BMD markedly increased in patients aged 40 years or older, when menopause occurs. Furthermore, in female stone patients with hypercalciuria, the frequency of reduced BMD reached more than 40%. When the cause was non-dietary hypercalciuria (classified mainly on the daily amount of urinary calcium excretion after ingestion of calculus test diet), the frequency of reduced BMD reached 65% (P < 0.01). Conclusions:, In case female stone patients with non-dietary hypercalciuria become menopausal, not only the risk of recurrent lithiasis increases, but the possibility of developing osteopenia in the future also increases. Appropriate treatments for prophylactic effects on urolithiasis or osteopenia should be considered, as judged from BMD, diet, sex, urinary calcium excretion and other factors synthetically. [source] Annual changes of the incidence and clinical characteristics of magnesium ammonium phosphate urinary stonesINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2003TAKAHIDE OGATA Abstract Background: Magnesium ammonium phosphate (MAP) urinary stones account for the majority of staghorn stones and frequently cause a non-functioning kidney. In the present study, we examined the annual changes of the number and clinical characteristics of MAP stones. Methods: The annual incidence of MAP stones was investigated in 2619 patients with urinary stones in whom composition of the stone was analysed at Chiba University Hospital between 1964 and 1999. In addition, the annual number of patients with MAP stones was examined at Funabashi Clinic. In a total of 644 patients with MAP stones, age and sex of the patients, location and size of the MAP stones, urinary cultures and etiological factors were analysed. Results: The number of MAP stones in the lower urinary tract was relatively constant. In contrast, MAP stones in the upper urinary tract had dramatically decreased since 1989, resulting in an increase in the rate of MAP stones in the lower urinary tract. Age distribution of the MAP stone patients ranged from 10 years to >,80 years, with the majority aged 30,60 years. The proportion of larger MAP stones in the upper urinary tract increased. There was no significant difference in prevalence of urine cultures. Among etiological factors for MAP stones, difficulty on urination tended to be common in recent years. Conclusion: The number of MAP stones, especially in upper urinary tract, has been decreasing during the last decade. At present, treatment of urinary tract obstruction seems important for the management of MAP stones in lower urinary tract. [source] Genetic Hypercalciuric Stone-Forming Rats Have a Primary Decrease in BMD and Strength,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2009Marc Grynpas Abstract Kidney stone patients often have a decrease in BMD. It is unclear if reduced BMD is caused by a primary disorder of bone or dietary factors. To study the independent effects of hypercalciuria on bone, we used genetic hypercalciuric stone-forming (GHS) rats. GHS and control (Ctl) rats were fed a low Ca (0.02% Ca, LCD) or a high Ca (1.2% Ca, HCD) diet for 6 wk in metabolic cages. All comparisons are to Ctl rats. Urine Ca was greater in the GHS rats on both diets. GHS fed HCD had reduced cortical (humerus) and trabecular (L1,L5 vertebrae) BMD, whereas GHS rats fed LCD had a reduction in BMD similar to Ctl. GHS rats fed HCD had a decrease in trabecular volume and thickness, whereas LCD led to a ,20-fold increase in both osteoid surface and volume. GHS rats fed HCD had no change in vertebral strength (failure stress), ductibility (failure strain), stiffness (modulus), or toughness, whereas in the humerus, there was reduced ductibility and toughness and an increase in modulus, indicating that the defect in mechanical properties is mainly manifested in cortical, rather than trabecular, bone. GHS rat cortical bone is more mineralized than trabecular bone and LCD led to a decrease in the mineralization profile. Thus, the GHS rats, fed an ample Ca diet, have reduced BMD with reduced trabecular volume, mineralized volume, and thickness, and their bones are more brittle and fracture prone, indicating that GHS rats have an intrinsic disorder of bone that is not secondary to diet. [source] Mechanism of Formation of Human Calcium Oxalate Renal Stones on Randall's PlaqueTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2007Andrew P. Evan Abstract Although calcium oxalate (CaOx) renal stones are known to grow attached to renal papillae, and specifically to regions of papillae that contain Randall's plaque (interstitial apatite deposits), the mechanisms of stone overgrowth on plaque are not known. To investigate the problem, we have obtained biopsy specimens from two stone patients that included an attached stone along with its tissue base and have studied the ultrastructural features of the attachment point using light and transmission electron microscopy, Fourier transform infrared spectroscopy (,-FTIR), and immunohistochemical analysis. The epithelium is disrupted at the attachment site. The denuded plaque that borders on the urinary space attracts an envelope of ribbon-like laminates of crystal and organic matrix arising from urine ions and molecules. Into the matrix of this ribbon grow amorphous apatite crystals that merge with and give way to the usual small apatite crystals imbedded in stone matrix; eventually CaOx crystals admix with apatite and become the predominant solid phase. Over time, urine calcium and oxalate ions gradually overgrow on the large crystals forming the attached stone. Anat Rec, 290:1315-1323, 2007. © 2007 Wiley-Liss, Inc. [source] | ||||||||||