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Tract Stones (tract + stone)

Distribution by Scientific Domains
Medical Sciences100%

Kinds of Tract Stones

  • urinary tract stone
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    Selected Abstracts

    Urolithiasis in Okinawa, Japan: A relatively high prevalence of uric acid stones

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 8 2003
    RAYHAN ZUBAIR HOSSAIN
    Abstract Aim:, The aim of the present study was to investigate the composition of urinary tract stones in patients from Okinawa, the most southern island group of Japan. Methods:, The study was conducted by 12 hospitals in Okinawa. A total of 1816 urinary tract calculi were obtained from 1816 patients (1323 males; 493 females). The patients had a mean age of 53 ± 15.3 years (mean ± SD). The calculi were examined to determine their chemical composition. Stone samples were analyzed by computed infrared spectrophotometer. Results:, Pure stones comprised 58.4% of the total, with calcium oxalate stones accounting for 40% (21% monohydrate [whewellite]; 6.6% dihydrate [weddellite]; and 12.4% combined monohydrate and dihydrate stones), uric acid/urate stones for 9.6%, calcium phosphate stones for 5.1%, and struvite stones for 3.7%. The other 41.6% of the stones consisted of calcium oxalate mixed with other components. The male-to-female ratio was 2.7 : 1. Conclusion:, In our series, calcium oxalate stones accounted for 81.6% of the urinary tract calculi, while uric acid/urate stones accounted for 15.8%. Uric acid stones, predominantly the anhydrous and/or dihydrate forms, showed a relatively high prevalence. Calcium oxalate stones, predominantly in the form of whewellite, showed a high prevalence among pure calculi; while the predominant combinations among mixed calculi were weddellite + calcium phosphate and whewellite + uric acid/urate. [source]

    Retrograde ureteroscopic endopyelotomy using the holmium:YAG laser

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2002
    Hatsuki Hibi
    Abstract Background: We report our experience of retrograde ureteroscopic endopyelotomy using the holmium laser for ureteropelvic junction (UPJ) obstruction not associated with upper tract stones. Methods: We carried out this procedure on five patients through an 8-Fr semirigid ureteroscope. The ureter was not stented before the procedure and balloon dilation was not necessary before retrograde insertion of the ureteroscope. The obstruction was incised with the holmium laser using a 200 µm fiber in a linear fashion. After completion of the incision, a 12-Fr double-J ureteral stent was left for 6 weeks. Thereafter, patients were monitored with renal scan and/or ultrasound and excretory urography at 3,6 month intervals. Results: Hydronephrosis was obviously improved in four cases (80%) at an average follow up of 12.8 months (4,23 months). Although the number of treated patients was small, retrograde ureteroscopic endopyelotomy for UPJ obstruction using the holmium laser achieved good results. Conclusions: We recommend that this procedure be used initially because it is less invasive and has a favorable outcome. [source]

    Unique pattern of urinary tract calculi in Australian Aboriginal children

    JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 5 2003
    PJ Carson
    Abstract Young Aboriginal children in remote regions of tropical and desert Australia are at risk of developing urate stones in their upper urinary tract from an early age. These radiolucent calculi were only recognized with the availability of ultrasound diagnosis and are not associated with anatomic anomalies or abnormal uric acid production/metabolism. Although these stones appear to resolve spontaneously after the weaning period, some result in ureteric obstruction and infection which may lead to renal damage. This pattern of urolithiasis differs from the usual global urolithiasis pattern of either endemic bladder stones in young children in developing countries or predominantly calcium-based stones in upper tracts of older children and adults in affluent industrialized countries, where upper tract urate stones account for only a minority of childhood urinary tract stones. Risk factors for urate stones are low urine output and acidic urine. An association between urolithiasis and carbohydrate intolerance leading to chronic acidosis has been suggested for Aboriginal children, but existing limited evidence does not support this as a major aetiological factor. Although further studies on the epidemiology, natural history and management of these urate stones are needed, we believe the focus should be on improving the known social and environmental risk factors of remote Aboriginal children during the weaning period which contribute to the unacceptably high prevalence of failure to thrive, diarrhoeal disease, environmental enteropathy, iron deficiency and urolithiasis. [source]

    Extracorporeal shock wave lithotripsy in children: equivalent clearance rates to adults is achieved with fewer and lower energy shock waves

    BJU INTERNATIONAL, Issue 1 2009
    Abraham Kurien
    OBJECTIVE To compare the outcome, safety and efficiency of extracorporeal shock wave lithotripsy (ESWL) using an electromagnetic lithotripter for upper urinary tract stones in children and adults. PATIENTS AND METHODS We retrospectively reviewed data over a 5-year period for patients with solitary, renal and upper ureteric stones measuring <2 cm in whom ESWL was the treatment method. Group A consisted of 44 children (mean [sd] age 5.9 [4.4] years) and group B of 562 adults (mean [sd] age 40.9 [13.1] years). The number and energy of SWs used was not predetermined and was tailored until adequate fragmentation was achieved. Initial stone reassessment was performed at 48 h and monthly thereafter. The number of SWs, intensity of SWs, stone-free rate, auxiliary procedure rate, re-treatment rate, complication rate and effectiveness quotient (EQ) were assessed in each group. RESULTS The stone-free rate with ESWL was 84% in children and 87% in adults (P = 0.78). The EQ was 77% and 75% in children and adults, respectively (P = 0.56). The mean (sd) number of SWs and energy required per session was 950 (349) and 11.83 (0.48) kV in children and 1262 (454) and 12.36 (0.34) kV in adults (P < 0.001). The re-treatment, auxiliary procedure and complication rates were similar in both groups. CONCLUSION ESWL is as safe and effective in children as in adults for solitary renal and upper ureteric stones that are <2 cm. Children required significantly fewer and lower energy SWs to achieve equivalent results. [source]

    Microbiological and clinical features of Corynebacterium urealyticum: urinary tract stones and genomics as the Rosetta Stone

    CLINICAL MICROBIOLOGY AND INFECTION, Issue 7 2008
    F. Soriano
    Abstract Corynebacterium urealyticum, formerly known as coryneform CDC group D2, was first recognized to be involved in human infections 30 years ago. It is a slow-growing, lipophilic, asaccharolytic and usually multidrug-resistant organism with potent urease activity. Its cell wall peptidoglycan, menaquinone, mycolic and cellular fatty acid composition is consistent with that of the genus Corynebacterium. DNA,DNA hybridization studies and 16S rDNA sequencing analysis have been used to determine the degree of relatedness of C. urealyticum to other corynebacterial species. The genome of the type strain consists of a circular chromosome with a size of 2 369 219 bp and a mean G + C content of 64.2%, and analysis of its genome explains the bacterium's lifestyle. C. urealyticum is a common skin colonizer of hospitalized elderly individuals who are receiving broad-spectrum antibiotics. It is an opportunistic pathogen causing mainly acute cystitis, pyelonephritis, encrusted cystitis, and encrusted pyelitis. More infrequently, it causes other infections, but mainly in patients with urological diseases. Infections are more common in males than in females, and treatment requires administration of antibiotics active against the organism in vitro, mainly glycopeptides, as well as surgical intervention, the latter mostly in cases of chronic infection. Mortality directly associated with infection by this organism is not frequent, but encrusted pyelitis in kidney-recipient patients may cause graft loss. The outcome of infection by this organism is reasonably good if the microbiological diagnosis is made and patients are treated appropriately. [source]