Hyperuricosuria Research Articles

Частота асимптоматической гиперурикемии среди взрослых больных сахарным диабетом 1-го и 2-го типа

Цель исследования — изучить частоту асимптоматической гиперурикемии у больных сахарным диабетом (СД) 1-го и 2-го типа в украинской популяции на примере жителей г. Харькова и области. Материалы и методы. Обследованы 316 больных СД: 81 больной СД 1-го типа (группа 1), 150 больных СД 2-го типа (группа 2) и 85 больных СД 2-го типа с абсолютной инсулинозависимостью (группа 3). Оценку состояния пуринового обмена проводили путем определения концентрации мочевой кислоты в сыворотке крови и моче. Уровни мочевой кислоты определяли колориметрическим методом с помощью набора реагентов «СпайнЛаб, UricasePOD» (Украина). Для оценки влияния возраста больного, возраста больного на момент манифестации заболевания, продолжительности заболевания и индекса массы тела группы обследуемых были разделены на две подгруппы (А и Б соответственно) с учетом уровня урикемии и урикурии. Подгруппу 1А составили 60 больных СД 1-го типа без гиперурикемии (ГУ) и/или гиперурикурии (ГУУ), подгруппу 1Б — 21 больной с ГУ и/или ГУУ, подгруппу 2А — 76 больных без ГУ и/или ГУУ, подгруппу 2Б — 74 больных с ГУ и/или ГУУ, подгруппу 3А — 57 больных без ГУ и/или ГУУ, подгруппу 3Б — 28 больных с ГУ и/или ГУУ. Результаты. Частота нарушений пуринового обмена среди взрослых больных СД 1-го и 2-го типа составляет 38,9 %. Самая высокая частота нарушений пуринового обмена наблюдается у больных СД 2-го типа (49,3 %). Возраст больного при проведении исследования и на момент манифестации СД, продолжительность заболевания и индекс массы тела не являются определяющими факторами, влияющими на формирование нарушений пуринового обмена у больных СД 1-го и 2-го типа; возрастной фактор и продолжительность заболевания являются факторами риска нарушений пуринового обмена у больных СД 2-го типа с абсолютной инсулинозависимостью. Выводы. Асимптоматическая гиперурикемия диагностирована у 27,8 % обследованных больных сахарным диабетом. Частота асимптоматической гиперурикемии значительно выше у больных сахарным диабетом 2-го типа, чем у больных сахарным диабетом 1-го типа (3,48 и 24,4 % соответственно); абсолютная инсулинозависимость у больных сахарным диабетом 2-го типа не влияет на частоту асимптоматической гиперурикемии.

Urolithiasis in Asian children: Evaluation of metabolic factors

This study was conducted to review urolithiasis in Asian children with a focus on urinary metabolic factors. A liter- ature search of Pub Med and Google identified pertinent articles from 20 different Asian countries which were subsequently reviewed. A totally of 12.913 children (M/F ratio of 2.37/1) were enrolled in the studies. Hypercalciuria, hyperuricosuria, hy- peroxaluria, hypocitraturia and decreased urinary magnesium excretion were reported in 652 of 4509 (14.45%), 276 of 3137 (8.8%), 1053 of 3973 (26.5%), 1940 of 2846 (68.2%), 32 of 240 (13.3%) of subjects, respectively. Cystinuria was noted in 112 of 4106 (2.7%) and mixed metabolic abnormalities were found in 175 of 724 (24.2%) patients. Association of urinary tract infection with stone disease was common in our series (2454 of 6430; (38.16) cases). Urologic abnormalities were uncommon and rec- orded in only 447 of 9788 patients (4.5%). The etiology of stone formation was idiopathic in 731 of 2731 (26.8%) patients. Analysis of 3977 stones indicated that 983 (24.9%) were pure Ca stones, whereas 1579 (40%), 411 (10.4%), 38 (0.95%) and 288 (7.35%) were mixed Ca, uric acid or urate, cystine and struvite stones respectively. The study showed that hypocitraturia and hyperoxaluria are the most common metabolic abnormalities. Overall, calcium was the main component of stones with the except that bladder stones were composed of urate or uric acid alone or in combination with calcium. In addition, uric acid stones which are uncommon among American children were frequently reported in Asian children.

Metabolic Syndrome and Nephrolithiasis Risk: Should the Medical Management of Nephrolithiasis Include the Treatment of Metabolic Syndrome?

This article reviews the relationship between metabolic syndrome (MetS) and nephrolithiasis, as well as the clinical implications for patients with this dual diagnosis. MetS, estimated to affect 25% of adults in the United States, is associated with a fivefold increase in the risk of developing diabetes, a doubling of the risk of acquiring cardiovascular disease, and an increase in overall mortality. Defined as a syndrome, MetS is recognized clinically by numerous constitutive traits, including abdominal obesity, hypertension, dyslipidemia (elevated triglycerides, low high-density lipoprotein cholesterol), and hyperglycemia. Urologic complications of MetS include a 30% higher risk of nephrolithiasis, with an increased percentage of uric acid nephrolithiasis in the setting of hyperuricemia, hyperuricosuria, low urine pH, and low urinary volume. Current American Urological Association and European Association of Urology guidelines suggest investigating the etiology of nephrolithiasis in affected individuals; however, there is no specific goal of treating MetS as part of the medical management. Weight loss and exercise, the main lifestyle treatments of MetS, counter abdominal obesity and insulin resistance and reduce the incidence of cardiovascular events and the development of diabetes. These recommendations may offer a beneficial adjunctive treatment option for nephrolithiasis complicated by MetS. Although definitive therapeutic recommendations must await further studies, it seems both reasonable and justifiable for the urologist, as part of a multidisciplinary team, to recommend these important lifestyle changes to patients with both conditions. These recommendations should accompany the currently accepted management of nephrolithiasis.

The clinical spectrum of idiopathic hyperuricosuria in children: Isolated and associated with hypercalciuria/hyperoxaluria

The clinical manifestations of hyperuricosuria (HU) are usually underestimated by the clinician. The aim of this study was to review the clinical spectrum of symptomatology of HU and to evaluate the presence of associated hypercalciuria (HC) and hyperoxaluria (HX). A retrospective review was done on 64 children with HU seen between January 2004 and December 2008. The patients were divided into HU 19, HU + HC 4, HU + HX 21 and HU + HC + HX 20. The mean age at diagnosis was 80 months (range six to 156 months). Duration of follow-up ranged was from six to 66 months. There were 228 symptomatic episodes for 64 patients (males 31, females 33). The relationship of symptomatology to age and gender were not significant. The most common symptoms were abdominal pain 67.2% (in 7/44 it was localized to the right lower quadrant, mimicking appendicitis), flank pain 59.4%, increased urinary frequency 43.4%, urgency 39%, enuresis 31.25%, oliguria 29.7%, dysuria 25%, red urine 20.35%, vaginal itching 15.21%, dribbling 14.06%, orange urine 12.5%, hesitancy 12.5% and penile pain 7.81%. To our knowledge, the vaginal itching and penile pain were not previously described. Family history was positive for stones and/or gout in 62.5%. The presence of a positive family history and red urine were significant (P-value <0.05) for the presence of an underlying HU. In the presence of recurrent abdominal/flank pain, hematuria without proteinuria or edema and urological symptomatology, especially in the presence of red urine, and a positive family history of gout or stones, a search for HU is in order. This will avoid unnecessary and invasive investigations.

Differing urinary urea excretion among children with idiopathic hypercalciuria and/or hyperuricosuria

Objective To estimate dietary protein intake in children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU). Patients and methods We compared the 24-h urinary excretion of urea, as a reflection of protein intake, in four age- and sex-matched groups, each comprising 56 consecutive children: (1) HC, (2) HU, (3) HC + HU and (4) control. Results Urinary urea excretion was significantly higher in HC, HU and HC + HU than in controls. HC and HU children had similar urea excretion. HC + HU children had urinary urea significantly higher than HC and HU, but urinary calcium similar to HC and urinary uric acid excretion similar to HU subjects. Urinary calcium was significantly ( R 2 = 0.21) correlated with urea excretion in HC children only, whereas urinary uric acid was significantly ( R 2 = 0.21) correlated with urinary urea in HU children only. No significant correlation between urinary urea and calcium or uric acid excretion was found in HC + HU patients although they had the highest urinary urea. A significant ( p = 0.004) interaction between urinary urea and sodium in increasing urinary calcium excretion resulted only in the HC group. Conclusion The association of dietary protein excess with HC and/or HU is conditioned by an individual (genetic?) predisposition and may be produced by different mechanisms.

Idiopathic hyperuricosuria, hypercalciuria and infantile renal stone disease: new association and therapeutic approach

Background: Urolithiasis in association with idiopathic hypercalciuria (IHC) plus idiopathic hyperuricosuria (IHU) has been reported in older children and adult patients only. IHU plus IHC in association with progressive infantile bilateral renal stone disease has not been previously reported during the first year of life. Aim: The aim of this paper is to report the novel association of IHU, IHC and progressive infantile bilateral renal stone disease and also to report our therapeutic approach for this new association, combining traditional treatments of hyperuricosuria (HU) and hypercalciuria (HC) with recently used essential oil terpenes in the management of childhood and infantile urolithiasis. Patients & methods: An 8.5-month old boy was referred with bilateral multiple stone disease. He initially presented with excessive crying and irritability since early infancy. The first renal stone was detected using ultrasound and intravenous pyelogram (IVP) at the age of 4 months. On referral, he showed signs ...

Central/diffuse abdominal perception of urological pain in children

In children with recurrent abdominal pain (RAP), the location of pain to the flank may suggest the involvement of the urinary apparatus. We aimed to evaluate the location of pain in different age groups of children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU) and RAP. Location of pain was assessed in 180 consecutive HC/HU children with RAP, aged 3-17.6 y, presenting to a single centre. Considering four age groups, central/diffuse was more prevalent than lateral location of pain in youngsters, with a progressive and significant (p<0.0001, chi2 test for trend) decrease of the prevalence of central/diffuse location with rising age, and with the most relevant drop after age 8 y. Location of pain was central/diffuse in 81% of patients under and lateral in 79% of those over 8 y of age (p<0.0001). The location of pain changed from central/diffuse to lateral in 16/18 children followed at least 1 y, within 1 to 2 y by age 8. Only after 8 y of age did the lateral location of abdominal pain become the rule in children with HC/HU and RAP. This has to be kept in mind in order to avoid overlooking the urologic origin of pain.

Central/diffuse abdominal perception of urological pain in children

Abstract Aim: In children with recurrent abdominal pain (RAP), the location of pain to the flank may suggest the involvement of the urinary apparatus. We aimed to evaluate the location of pain in different age groups of children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU) and RAP. Methods: Location of pain was assessed in 180 consecutive HC/HU children with RAP, aged 3–17.6 y, presenting to a single centre. Results: Considering four age groups, central/diffuse was more prevalent than lateral location of pain in youngsters, with a progressive and significant (p&lt;0.0001, χ2 test for trend) decrease of the prevalence of central/diffuse location with rising age, and with the most relevant drop after age 8 y. Location of pain was central/diffuse in 81% of patients under and lateral in 79% of those over 8 y of age (p&lt;0.0001). The location of pain changed from central/diffuse to lateral in 16/18 children followed at least 1 y, within 1 to 2 y by age 8. Conclusion: Only after 8 y of age did the lateral location of abdominal pain become the rule in children with HC/HU and RAP. This has to be kept in mind in order to avoid overlooking the urologic origin of pain.

Appendectomy in children with hypercalciuria/hyperuricosuria

Recurrent abdominal pains (RAPs) represent a common problem in children sometimes leading to unnecessary and invasive procedures. The rates of appendectomy were evaluated consecutively in 180 children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU) and RAPs, and in 270 control subjects. Of the HC/HU patients 10% and of controls 1.5% underwent appendectomy ( p < 0.0001). In 15 out of 18 HC/HU patients appendectomized, RAPs persisted with the same frequency and severity after the operation; 10 out of 18 had dysuria and/or gross hematuria 2 days–12 months after appendectomy. At our first visit, urinalysis was negative for hematuria in 13 out of 18 patients and in eight out of the 10 with a previous history of dysuria or gross hematuria. Pain recurrences resolved or improved in nine out of the 11 patients followed at least 1 year after general or specific therapy for HC/HU. The inconstant association of dysuria and hematuria with RAPs in children with HC/HU may lead to the urological origin of pain being overlooked, and may explain the high rate of appendectomy among these children. The possibility of HC/HU therefore should be taken into account in children with RAPs even when dysuria and hematuria are not present.

Hyperuricosuria in children: clinical presentation and natural history.

Idiopathic hyperuricosuria (HU) was previously reported in only a limited number of children with hematuria. We aimed to outline the clinical presentation and natural history of HU not only in children with hematuria, but also in those with dysuria and/or recurrent abdominal/flank pain and a family history of urolithiasis. Retrospective analysis of data at diagnosis from 102 consecutive children with HU and outcome analysis of 26 of them who were followed >/=1 years (mean: 3.1) with no specific therapy. Sixty-one participants had HU and 41 had HU + hypercalciuria. Fifty-two patients had no hematuria among the presenting symptoms, more than one third had normal urinalysis at our first examination, one half had microcalculi (<3 mm in diameter) at renal sonography, and 12% had stones (4-18 mm). Thirty participants of the 39 with no hematuria at our first examination (77%) showed microcalculi or calculi at renal sonography. The patients with microcalculi were significantly older than were those without microcalculi. During the follow-up, 4 of 26 children never had hematuria and 8 had no hematuria during most of the follow-up period. Two patients who had a calculus at first visit and 3 who formed calculi 4 to 12 mm in diameter, after 1 to 3.5 years subsequently passed them in the urine. The lack of hematuria is not predictive of absence of urolithiasis. Therefore, it may be misleading to judge on the efficacy of a given therapy only based on disappearance of hematuria. HU and hypercalciuria have to be suspected in children with dysuria and those with recurrent abdominal/flank pain and familial history of urolithiasis, although they have no hematuria.

Idiopathic hypercalciuria and hyperuricosuria: family prevalence of nephrolithiasis.

We studied the prevalence of a history of nephrolithiasis in first- and second-degree relatives of 74 children with hypercalciuria (HC), 61 with hyperuricosuria (HU), and 41 with HC plus HU, and in a control population of 261 children with different diseases. Family history of nephrolithiasis was found in 69% of HC, 75% of HU, 78% of HC plus HU, and 22% of control patients. The prevalence was not different among HC, HU, and HC plus HU groups, but was significantly higher in each study group than the control group (P=0.0001). Body mass index >95th percentile was found in only 4.7% of the patients with HC or HC plus HU. Calculi (>3 mm in diameter) were present in 8.9% of the patients with a family history of nephrolithiasis and in 9.4% of those with no family history (P=0.85). Microcalculi (<3 mm in diameter) were found by sonography in 56.6% of the patients with and in 53.3% of those without a family history of nephrolithiasis (P=0.83). Children with HC and/or HU have a strong familial prevalence of nephrolithiasis. Obesity does not seem to affect the association of familial nephrolithiasis and hypercalciuria in children. The presence of nephrolithiasis in families of children with HC and/or HU is not associated with a higher rate of formation of calculi or microcalculi.

Association of thin basement membrane nephropathy with hypercalciuria, hyperuricosuria and nephrolithiasis

Familial persistent microhematuria with normal renal function is the most common presentation of thin basement membrane nephropathy (TBMN). Gross hematuria episodes and loin pain attacks are other manifestations of the disease. On the other hand, it has been shown that hypercalciuria (HC) and hyperuricosuria (HU) can produce both gross or microscopic non-glomerular hematuria, in addition to their role in renal stone formation. We studied the prevalence of HC, HU and nephrolithiasis in a group of 27 biopsy-proven TBMN as well as in 19 non-biopsied first-degree relatives with persistent microhematuria and 25 first-degree relatives without microhematuria. A group of 27 patients with IgA nephropathy (IgAN) and persistent microhematuria, and another group of 20 healthy subjects without known renal diseases were selected as control groups. Ten (37%) patients with TBMN and 8 (42%) relatives with microhematuria showed HC and/or HU at presentation; relatives without microhematuria, IgAN patients and normal controls showed a significantly lower prevalence of HC and HU. The prevalence of previous nephrolithiasis among TBMN patients (25%) was significantly higher than in IgAN patients (3%; P < 0.05). Family history of nephrolithiasis was recorded in 14 (51%) of the 27 TBMN families, in contrast with 2 of 27 (7%) with IgAN and 1 of 20 (5%) in normal controls (P < 0.05). The prevalence of nephrolithiasis, gross hematuria bouts and loin pain episodes among TBMN patients and microhematuric relatives showing HC and/or HU at presentation (44%, 44% and 27%, respectively) were significantly higher than those of TBMN patients and microhematuric relatives with normal calcium and uric acid urinary excretions (10%, 7% and 3%, respectively; P < 0.05). At the end of follow-up (8.8+/-4.1 years in TBMN patients and 9.1+/-4.2 years in relatives with microhematuria), all the cases maintained normal renal function. We found a high prevalence of HC, HU, and nephrolithiasis among TBMN patients and relatives with microhematuria. Our study also shows a significant relationship between the presence of HC and/or HU and the prevalence of nephrolithiasis, gross hematuria bouts and loin pain episodes.

Metabolic Evaluation of Patients With Recurrent Idiopathic Calcium Nephrolithiasis

BACKGROUND Metabolic evaluation in recurrent idiopathic calcium renal stone-formers (RCSF) was analysed with respect to the following questions: (1) do three 24-h urines provide more diagnostic accuracy in the metabolic evaluation of RCSF than 1 or 2 urines?; (2) does time after stone event influence the diagnostic yield?; (3) is urine composition at weekends different from that at mid-week?; (4) what are the prevalences of the most important risk factors (RF) of idiopathic calcium nephrolithiasis, i.e. low volume (LV), hypercalciuria (HC), hyperoxaluria (HO), hyperuricosuria (HU), hypocitraturia (Hypo-Cit), and hypomagnesiuria (Hypo-Mg)?; and (5) do male RCSF differ from females with respect to urinary RFs? METHODS Seventy-five RCSF (59 men, 16 women) collected three 24-h urines (U1-3) while on free-choice diet. To account for possible variations in lifestyle and diet, U1 and U3 had to be collected midweek and U2 at a weekend. RESULTS When considering all three urines together (U1 + U2 + U3), the number of RF abnormalities/patient was 2.8 +/- 0.1, higher than numbers of any combination of two urines or of any single urine (P = 0.0001 for all comparisons). The number of RF abnormalities also rose with time after stone event, from 0.8 +/- 0.1 (range 0-4) in U1 to 1.1 +/- 0.1 (range 0-4) in U3 (P = 0.011 vs U1). Whereas all other RF did not change between collections, urine volume was lower in U2 (1793 +/- 90 ml) than in U1 (2071 +/- 97 ml, P = 0.0001 vs U2) and U3 (1946 +/- 97 ml, P = 0.046 vs U2). At least 1 abnormality was found in 85.3% of all RCSF, and multiple abnormalities occurred in 47%. The most frequent RF was HC (39%), followed by HO and LV (32% each), Hypo-Cit (29%), HU (23%) and Hypo-Mg (19%). Males more often had Hypo-Cit (P < 0.001) and Hypo-Mg (P < 0.01) than females, whereas HO was more frequent in female RCSF (P < 0.025 vs males). CONCLUSIONS Diagnostic accuracy of metabolic evaluation in RCSF increases both with the number of urines collected and the time passing after a stone event. Urines collected at weekends differ from those of the week only by their lower volumes. Abnormalities of RF for calcium nephrolithiasis can be detected in 85.3% of RCSF, and HC is the most common RF both in male and female RCSF.

Metabolic evaluation of patients with recurrent idiopathic calcium nephrolithiasis.

Metabolic evaluation in recurrent idiopathic calcium renal stone-formers (RCSF) was analysed with respect to the following questions: (1) do three 24-h urines provide more diagnostic accuracy in the metabolic evaluation of RCSF than 1 or 2 urines?; (2) does time after stone event influence the diagnostic yield?; (3) is urine composition at weekends different from that at mid-week?; (4) what are the prevalences of the most important risk factors (RF) of idiopathic calcium nephrolithiasis, i.e. low volume (LV), hypercalciuria (HC), hyperoxaluria (HO), hyperuricosuria (HU), hypocitraturia (Hypo-Cit), and hypomagnesiuria (Hypo-Mg)?; and (5) do male RCSF differ from females with respect to urinary RFs? Seventy-five RCSF (59 men, 16 women) collected three 24-h urines (U1-3) while on free-choice diet. To account for possible variations in lifestyle and diet, U1 and U3 had to be collected midweek and U2 at a weekend. When considering all three urines together (U1 + U2 + U3), the number of RF abnormalities/patient was 2.8 +/- 0.1, higher than numbers of any combination of two urines or of any single urine (P = 0.0001 for all comparisons). The number of RF abnormalities also rose with time after stone event, from 0.8 +/- 0.1 (range 0-4) in U1 to 1.1 +/- 0.1 (range 0-4) in U3 (P = 0.011 vs U1). Whereas all other RF did not change between collections, urine volume was lower in U2 (1793 +/- 90 ml) than in U1 (2071 +/- 97 ml, P = 0.0001 vs U2) and U3 (1946 +/- 97 ml, P = 0.046 vs U2). At least 1 abnormality was found in 85.3% of all RCSF, and multiple abnormalities occurred in 47%. The most frequent RF was HC (39%), followed by HO and LV (32% each), Hypo-Cit (29%), HU (23%) and Hypo-Mg (19%). Males more often had Hypo-Cit (P < 0.001) and Hypo-Mg (P < 0.01) than females, whereas HO was more frequent in female RCSF (P < 0.025 vs males). Diagnostic accuracy of metabolic evaluation in RCSF increases both with the number of urines collected and the time passing after a stone event. Urines collected at weekends differ from those of the week only by their lower volumes. Abnormalities of RF for calcium nephrolithiasis can be detected in 85.3% of RCSF, and HC is the most common RF both in male and female RCSF.