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Michel Daudon - One of the best experts on this subject based on the ideXlab platform.
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Comprehensive morpho-constitutional Analysis of urinary Stones improves etiological diagnosis and therapeutic strategy of nephrolithiasis
Comptes Rendus. Chimie, 2016Co-Authors: Michel Daudon, Arnaud Dessombz, Vincent Frochot, Letavernier Emmanuel, Jean-philippe Haymann, Paul Jungers, Dominique BazinAbstract:The generalized use of physical methods, X-ray diffraction and Fourier transform infrared spectroscopy (FTIR) decisively improved urinary Stone Analysis by allowing to accurately identify the chemical nature, crystalline phases and relative proportions of Stone constituents. Such compositional Analysis is sufficient to identify Stone diseases involving a single specific component such as cystine, 2,8-dihydroxyadenine (DHA), struvite, uric acid, ammonium hydrogen urate or a drug. However, for common calcium nephrolithiasis, which represents by far the largest part of urinary Stones throughout the world, the simple identification of calcium oxalate (CaOx) and/or calcium phosphate (CaP) as constituents provides incomplete etiologic information because a same elemental Stone composition may result from different lithogenic processes. A more comprehensive method combining careful morphologic examination of the surface and the section of Stones with detailed FTIR Analysis of the nature, location, crystalline phases and a respective proportion of Stone constituents, therefore termed ‘morpho-constitutional’ Analysis, as used in our laboratory for four decades provides more complete etiologic information. In common idiopathic CaOx nephrolithiasis, the predominance of the monohydrate form (COM) was shown to be associated with elevated urine Ox concentration, whereas the dihydrate form (COD) was associated with hypercalciuria, thus orienting dietary and/or pharmacological intervention. A major contribution of the method is to immediately orient the diagnosis of rare, but severe, diseases leading to a loss of renal function, when Stone Analysis reveals a peculiar morphology of common constituents. The most salient examples are the type Ic morphology of COM Stones, pathognomonic of primary hyperoxaluria, type Ie morphology, which is highly suggestive of absorptive hyperoxaluria as seen in inflammatory bowel diseases and pathologies inducing steatorrhea, type IIId morphology of ammonium urate Stones, which orientates towards chronic diarrhea with dietary imbalance and loss of electrolytes, and type IVa2 morphology of carbapatite, specific of distal renal tubular acidosis of congenital or acquired origin, and distinctive aspect of 2,8-DHA Stones. In conclusion, the proposed morpho-constitutional method should be recommended for routine Stone Analysis, inasmuch as it is simple, rapid, reliable, clinically relevant and cost-effective.
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Quality Assessment of Urinary Stone Analysis: Results of a Multicenter Study of Laboratories in Europe
PLoS ONE, 2016Co-Authors: Roswitha Siener, Michel Daudon, Noor Buchholz, Bernhard Hess, Thomas Knoll, Palle J. Osther, José Reis-santos, Kemal Sarica, Olivier Traxer, Alberto TrinchieriAbstract:After Stone removal, accurate Analysis of urinary Stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the Stone-forming patient. The most common techniques for routine Analysis of Stones are infrared spectroscopy, X-ray diffraction and chemical Analysis. The aim of the present study was to assess the quality of urinary Stone Analysis of laboratories in Europe. Nine laboratories from eight European countries participated in six quality control surveys for urinary calculi analyses of the Reference Institute for Bioanalytics, Bonn, Germany, between 2010 and 2014. Each participant received the same blinded test samples for Stone Analysis. A total of 24 samples, comprising pure substances and mixtures of two or three components, were analysed. The evaluation of the quality of the laboratory in the present study was based on the attainment of 75% of the maximum total points, i.e. 99 points. The methods of Stone Analysis used were infrared spectroscopy (n = 7), chemical Analysis (n = 1) and X-ray diffraction (n = 1). In the present study only 56% of the laboratories, four using infrared spectroscopy and one using X-ray diffraction, fulfilled the quality requirements. According to the current standard, chemical Analysis is considered to be insufficient for Stone Analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infra-red spectroscopy highlight the importance of equipment, reference spectra and qualification of the staff for an accurate Analysis of Stone composition. Regular quality control is essential in carrying out routine Stone Analysis.
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calcium phosphate Stone morphology can reliably predict distal renal tubular acidosis
The Journal of Urology, 2015Co-Authors: Emmanuel Letavernier, D Bazin, Arnaud Dessombz, Jean-philippe Haymann, Michel DaudonAbstract:Purpose: Calcium Stones represent 85% to 90% of all urinary calculi, including various crystalline compositions and etiological conditions. Calcium phosphate accounts for 10% to 15% of cases. These Stones are mainly related to 3 groups of risk factors, including calcium or phosphate metabolism disturbance, renal acidification defects and urinary tract infection. Identifying the Stone etiology often requires extensive metabolic evaluation. We assessed whether Stone Analysis including morphological typing in addition to Stone composition could be a valuable help for diagnosis.Materials and Methods: Of 60,564 Stones analyzed by morphological examination and infrared spectroscopy at our laboratory 6,439 (10.6%) were mainly composed of carbapatite. Of these Stone 1,093 patients were included in study who had an available etiological diagnosis and Stones containing at least 70% of calcium phosphate without struvite.Results: Of the 1,093 calcium phosphate Stones 12.8% showed a peculiar morphology termed IVa2, ch...
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kidney Stone Analysis give me your Stone i will tell you who you are
World Journal of Urology, 2015Co-Authors: Jonathan Cloutier, Olivier Traxer, Luca Villa, Michel DaudonAbstract:Introduction Stone Analysis is an important part in the evaluation of patients having Stone disease. This could orientate the physician toward particular etiologies.
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adenine phosphoribosyltransferase deficiency
Clinical Journal of The American Society of Nephrology, 2012Co-Authors: Guillaume Bollee, Jerome Harambat, A Bensman, Bertrand Knebelmann, Michel Daudon, Irene CeballospicotAbstract:Summary Complete adenine phosphoribosyltransferase (APRT) deficiency is a rare inherited metabolic disorder that leads to the formation and hyperexcretion of 2,8-dihydroxyadenine (DHA) into urine. The low solubility of DHA results in precipitation of this compound and the formation of urinary crystals and Stones. The disease can present as recurrent urolithiasis or nephropathy secondary to crystal precipitation into renal parenchyma (DHA nephropathy). The diagnostic tools available—including Stone Analysis, crystalluria, and APRT activity measurement—make the diagnosis easy to confirm when APRT deficiency is suspected. However, the disease can present at any age, and the variability of symptoms can present a diagnostic challenge to many physicians. The early recognition and treatment of APRT deficiency are of crucial importance for preventing irreversible loss of renal function, which still occurs in a non-negligible proportion of cases. This review summarizes the genetic and metabolic mechanisms underlying Stone formation and renal disease, along with the diagnosis and management of APRT deficiency.
De Rooster Hilde - One of the best experts on this subject based on the ideXlab platform.
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Prevalentie van urolithiasis en andere urinaire afwijkingen bij honden met een congenitale extrahepatische portosystemische shunt = Prevalence of urolithiasis and other urinary abnormalities in dogs with a congenital extrahepatic portosystemic shunt
'Ghent University', 2020Co-Authors: Van Riet Tessa, Devriendt Nausikaa, Serrano Gonçalo, Stock Emmelie, Paepe Dominique, De Rooster HildeAbstract:Dogs with a portosystemic shunt (PSS) often have urinary abnormalities. In this retrospective study, the prevalence of urolithiasis and other urinary abnormalities secondary to extrahepatic (EH)PSS was determined from the onset of the clinical signs until the day of surgical correction of the PSS. About 67% of all dogs were presented with urinary complaints that were directly (39%) or probably (28%) related to the EHPSS. Some dogs had surgery for urolithiasis and subsequent quantitative Stone Analysis revealed ammonium biurate uroliths , suggesting the presence of an underlying PSS. Additionally, 77% of the dogs that did not have any urinary complaints appeared to have urinary abnormalities based on medical imaging and/or urinalysis. Overall, 70.4% of the dogs had urolithiasis. In this study, the importance of performing a complete urinalysis, supplemented with medical imaging of the urinary system in all dogs with an EHPSS is demonstrated. In addition, the importance of quantitative Analysis of uroliths is stressed, as the presence of ammonium biurate may be suggestive of a PSS
Hilde De Rooster - One of the best experts on this subject based on the ideXlab platform.
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prevalentie van urolithiasis en andere urinaire afwijkingen bij honden met een congenitale extrahepatische portosystemische shunt prevalence of urolithiasis and other urinary abnormalities in dogs with a congenital extrahepatic portosystemic shunt
Vlaams Diergeneeskundig Tijdschrift, 2020Co-Authors: Tessa Van Riet, Nausikaa Devriendt, Goncalo Serrano, Emmelie Stock, Dominique Paepe, Hilde De RoosterAbstract:Dogs with a portosystemic shunt (PSS) often have urinary abnormalities. In this retrospective study, the prevalence of urolithiasis and other urinary abnormalities secondary to extrahepatic (EH)PSS was determined from the onset of the clinical signs until the day of surgical correction of the PSS. About 67% of all dogs were presented with urinary complaints that were directly (39%) or probably (28%) related to the EHPSS. Some dogs had surgery for urolithiasis and subsequent quantitative Stone Analysis revealed ammonium biurate uroliths , suggesting the presence of an underlying PSS. Additionally, 77% of the dogs that did not have any urinary complaints appeared to have urinary abnormalities based on medical imaging and/or urinalysis. Overall, 70.4% of the dogs had urolithiasis. In this study, the importance of performing a complete urinalysis, supplemented with medical imaging of the urinary system in all dogs with an EHPSS is demonstrated. In addition, the importance of quantitative Analysis of uroliths is stressed, as the presence of ammonium biurate may be suggestive of a PSS.
Irene Ceballospicot - One of the best experts on this subject based on the ideXlab platform.
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adenine phosphoribosyltransferase deficiency
Clinical Journal of The American Society of Nephrology, 2012Co-Authors: Guillaume Bollee, Jerome Harambat, A Bensman, Bertrand Knebelmann, Michel Daudon, Irene CeballospicotAbstract:Summary Complete adenine phosphoribosyltransferase (APRT) deficiency is a rare inherited metabolic disorder that leads to the formation and hyperexcretion of 2,8-dihydroxyadenine (DHA) into urine. The low solubility of DHA results in precipitation of this compound and the formation of urinary crystals and Stones. The disease can present as recurrent urolithiasis or nephropathy secondary to crystal precipitation into renal parenchyma (DHA nephropathy). The diagnostic tools available—including Stone Analysis, crystalluria, and APRT activity measurement—make the diagnosis easy to confirm when APRT deficiency is suspected. However, the disease can present at any age, and the variability of symptoms can present a diagnostic challenge to many physicians. The early recognition and treatment of APRT deficiency are of crucial importance for preventing irreversible loss of renal function, which still occurs in a non-negligible proportion of cases. This review summarizes the genetic and metabolic mechanisms underlying Stone formation and renal disease, along with the diagnosis and management of APRT deficiency.
A Hesse - One of the best experts on this subject based on the ideXlab platform.
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automated Analysis of urinary Stone composition using raman spectroscopy pilot study for the development of a compact portable system for immediate postoperative ex vivo application
The Journal of Urology, 2013Co-Authors: A Hesse, Arkadiusz Miernik, Yvan Eilers, Carsten Bolwien, Armin Lambrecht, Dieter Hauschke, Gunter Rebentisch, Phillipp S Lossin, Jens RassweilerAbstract:Purpose: We evaluate a compact portable system for immediate automated postoperative ex vivo Analysis of urinary Stone composition using Raman spectroscopy. Analysis of urinary Stone composition provides essential information for the treatment and metaphylaxis of urolithiasis. Currently infrared spectroscopy and x-ray diffraction are used for urinary Stone Analysis. However, these methods may require complex sample preparation and costly laboratory equipment. In contrast, Raman spectrometers could be a simple and quick strategy for immediate Stone Analysis.Materials and Methods: Pure samples of 9 Stone components and 159 human urinary calculi were analyzed by Raman spectroscopy using a microscope coupled system at 2 excitation wavelengths. Signal-to-noise ratio, peak positions and the distinctness of the acquired Raman spectra were analyzed and compared. Background fluorescence was removed mathematically. Corrected Raman spectra were used as a reference library for automated classification of native human...
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quality control in urinary Stone Analysis results of 44 ring trials 1980 2001
Clinical Chemistry and Laboratory Medicine, 2005Co-Authors: A Hesse, Rolf Kruse, W J Geilenkeuser, Matthias SchmidtAbstract:Urinary Stone Analysis is the most important diagnostic step after Stone removal from the body. The methods employed for these analyses are based on diverse analytical principles. Chemical methods are used for detecting individual ions. Infrared spectroscopy is used for examining molecular structures, and X-ray diffraction for determination of the crystalline structure of a substance. Since 1980, a twice-yearly ring trials quality control survey has been on offer to examine the quality of urinary Stone analyses. A summary of the results of 44 ring trials (1980-2001) has been compiled for individual pure substances and binary (two-component) mixtures. On average, 100 laboratories have participated in these ring trials. Initially, over 80% of the participants carried out their analyses using chemical methods. In 2001, this figure decreased to a mere 13%. In contrast, a progressive increase in the use of infrared spectroscopy was observed, up to 79% of all participants employed this method. X-Ray diffraction was only employed in a small number of specialised laboratories (5-9%). The chemical methods produced a very high proportion of errors (6.5-94%) with both the pure substances and binary mixtures, whereas high error rates for infrared spectroscopy and X-ray diffraction were confined to individual substances only. Due to the poor results in the ring trials, the majority of laboratories stopped using chemical Analysis, which is now considered to be obsolete. Regarding mixtures, error rates of over 10% also occurred with infrared spectroscopy and X-ray diffraction. Ring trials are indispensable for the quality management of urinary Stone Analysis.
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causes of phosphate Stone formation and the importance of metaphylaxis by urinary acidification a review
World Journal of Urology, 1999Co-Authors: A Hesse, D HeimbachAbstract:The most important phosphates involved in urinary Stone disease are carbonate apatite, brushite, and struvite. Overall, phosphate Stones account for 12-20% of all Stones, with a downward trend for struvite and an increase in carbonate apatite being observed in the last decade. The physicochemical basis for the formation of phosphate calculi is supersaturation. Once the solubility product has been exceeded, a metastable process of supersaturation begins, with slow crystalline growth. If a critical limit of supersaturation is exceeded, large-scale spontaneous precipitation of crystals occurs in a second stage. No urinary tract infection is involved in brushite Stone formation. Although infection is not a prerequisite for the formation of carbonate apatite Stones, infective conditions favor carbonate apatite formation. Struvite is the characteristic infection calculus, formed as a result of urinary tract infection with urease-producing bacteria. During the first episode of urinary Stone disease a definitive diagnosis of the type of Stone involved is very difficult without Analysis of the latter by infrared spectroscopy or X-ray diffraction. In recurrent disease, appropriate treatment can be initiated on the basis of the previous Stone Analysis in the majority of cases. The best means of preventing recurrent disease involving any type of phosphate Stone is definitive calculus removal by shock-wave lithotripsy, percutaneous Stone removal, or open surgery (especially in children). Chemolysis via acidification of the urine with Suby G solution or hemicidrin supported by oral acidification, achieved by the metabolism of L-methionine, and antibiotic therapy (especially for infectious Stones) are important adjuvant modalities of therapy. After therapy of phosphate Stones, metaphylaxis involving controlled urinary acidification with L-methionine supports the treatment of infection and, at a pH value of less than 6.2 and urine dilution to 2.5 l/24 h, prevents the crystallization of struvite, brushite, and carbonate apatite.