Prevalence and risk factors for hyperuricemia and hyperuricosuria in patients with hematologic malignancies.

Introduction: Hyperuricemia is a common complication of hematologic malignancies, and hyperuricosuria in this population has shown conflicting results. This study aimed to determine the prevalence of hyperuricemia and parameters associated with serum uric acid (SUA) and urine uric acid (UUA) in patients with lymphoma and myeloproliferative neoplasms (MPN). Methods: This cross-sectional study included adult patients with newly diagnosed lymphoma and MPN at the university-based hospital. Clinical characteristics were collected, and independent risk factors for hyperuricemia and hyperuricosuria were determined using multiple logistic regression. Results: One hundred and sixty-five patients were included with a median age of 55 years (45.5-64) and 51.5% were males. There were 91 patients (55.2%) with lymphoma and 74 cases (44.8%) of MPN. Overall, hyperuricemia was prevalent in 43.6% with a median SUA of 6.3 mg/dl (4.6-8) and hyperuricosuria was detected in 39.4% with a median 24-h UUA of 545 mg (365.4-991). Hyperuricemia was observed in patients with lymphoma and MPN in 20.9% and 71.6%, respectively, and hyperuricosuria in 15.4% and 68.9%, respectively. In lymphoma patients, estimated glomerular filtration rate (eGFR) <90 ml/min/1.73 m2 and serum lactate dehydrogenase (LDH) ≥ 250 U/L were associated with hyperuricemia with odds ratio (OR) 3.24, 95% confidence interval (CI) 1.95-11.07, p = 0.006 and OR 2.07, 95%CI 1.62-6.97, p = 0.039), and only elevated serum LDH was related to hyperuricosuria (OR 2.37, 95%CI 1.56-14.29, p = 0.036). In MPN patients, hemoglobin levels <10 g/dl and serum LDH ≥ 640 mg/dl were independent risk factors of hyperuricosuria (OR 1.88, 95%CI 1.42-8.39, p = 0.045 and OR 6.21, 95%CI 1.49-25.74, p = 0.012). Conclusion: Hyperuricemia in patients with hematologic malignancies was common, notably MPN, and parameters associated with hyperuricosuria were provided. In addition to the utilization of allopurinol in patients at high risk of tumor lysis syndrome, patients without hyperuricosuria may also be of significant interest.

Hyperuricosuria and hypercalciuria, probable etiologies of functional abdominal pain: A case-control study.

Background: Functional abdominal pain (FAP) is a common complaint causing several referrals to pediatricians. On the other hand, the most common presentation of hyperuricosuria and also hypercalciuria is chronic/recurrent abdominal pain. Therefore, a hypothesis has been raised; abdominal pain due to hyperuricosuria and/or hypercalciuria may be misdiagnosed as FAP. The current study has aimed to respond to this theory. Materials and Methods: This is a case-control study conducted on children diagnosed with FAP based on Rome IV criteria and age-matched normal controls. Blood and random urine samples were taken from healthy children and those with FAP. Random urine samples were examined for calcium, uric acid, oxalate, and creatinine concentrations. Random urine calcium to urine creatinine above 0.2 mg/mg was considered hypercalciuria and random urine uric acid above 0.56 mg/dl, GFR as hyperuricosuria. The data were analyzed using logistic models. Results: Hypercalciuric children had a significantly lower chance of FAP (odds ratio [OR] =0.425, 95% confidence interval [CI] =0.204-0.886). Although an inverse association was seen between hyperuricosuria and FAP (OR = 0.693, 95% CI = 0.395-1.214), it was not statistically significant. In stratified analyses by gender for both hyperuricosuria and hypercalciuria, a marginal inverse significant association was seen in male gender (P < 0.1). Conclusion: Our study showed that hypercalciuria is significantly in inverse association with FAP but not hyperuricosuria. Therefore, these disorders, particularly hyperuricosuria may not be considered as the possible causes of FAP. Further studies with larger sample size for providing more reliable evidence are recommended.

An evaluation of the roles of hematuria and uric acid in defining the prognosis of patients with IgA nephropathy.

In recent years, many significant advances have been made in determining which clinical manifestations and pathologic lesions can provide prognostic information for patients with IgA nephropathy (IgAN). However, some important questions remain, including the long-term consequences of hematuria, both macroscopic (MH) and microscopic (mH), in patients with IgAN. The importance of distinguishing patients who have a single episode of MH of long duration from those with recurrent episodes of short duration and the prognostic importance of the episodes of acute kidney injury (AKI) that sometimes accompany episodic MH will be discussed. Studies that have evaluated the mechanisms that may be responsible for recurrent MH and the toxic effects of red blood cells (RBCs), or their constituents, on kidney tubules will also be addressed. In the last section, I will review the evidence that hyperuricemia (HU) may be a significant independent risk factor for progressive kidney disease in patients with IgAN.

Diagnosis and Management of Nephrolithiasis in Children.

The incidence of kidney stones in children is increasing. Approximately two-thirds of pediatric cases have a predisposing cause. Children with recurrent kidney stones have an increased higher risk of developing chronic kidney. A complete metabolic workup should be performed. Ultrasound examination is the initial imaging modality recommended for all children with suspected nephrolithiasis. A general dietary recommendation includes high fluid consumption, dietary salt restriction, and increased intake of vegetables and fruits. Depending on size and location of the stone, surgical intervention may be necessary. Multidisciplinary management is key to successful treatment and prevention.

Calcium oxalate urolithiasis in juvenile dogs.

BACKGROUND: The features of juvenile-onset calcium oxalate urolithiasis in dogs have not been previously reported. METHODS: Calcium oxalate urolith submissions to the Minnesota Urolith Center between 2012 and 2016 were analyzed to identify those originating from juvenile (≤2 years, n = 510) or mature (7-9 years, n = 39,093) dogs. Breed, sex, urolith salt type and urolith location were compared between groups. Breeds represented in both groups were also compared with respect to sex, urolith salt type and urolith location. RESULTS: French (odds ratios [OR] = 14.7, p < 0.001) and English (OR = 14.3, p < 0.001) Bulldogs were overrepresented in juvenile submissions. All juvenile French and English Bulldogs were male. Across all breeds, juvenile dogs were more likely to be male (89%, p < 0.001) than mature dogs (79%). Juvenile dogs were also more likely to form dihydrate stones compared to mature dogs (33% versus 14%, respectively; p < 0.001). Breed differences were discovered in sex, urolith salt type and stone location. CONCLUSIONS: French and English Bulldogs comprise a greater proportion of juvenile calcium oxalate urolith submissions than expected based on their rarity in mature submissions. Inherited risk factors, particularly X chromosome variants, should be investigated due to the strong breed and sex predispositions identified.

Urate Transporters in the Kidney: What Clinicians Need to Know.

Urate is produced in the liver by the degradation of purines from the diet and nucleotide turnover and excreted by the kidney and gut. The kidney is the major route of urate removal and has a pivotal role in the regulation of urate homeostasis. Approximately 10% of the glomerular filtered urate is excreted in the urine, and the remainder is reabsorbed by the proximal tubule. However, the transport of urate in the proximal tubule is bidirectional: reabsorption and secretion. Thus, an increase in reabsorption or a decrease in secretion may induce hyperuricemia. In contrast, a decrease in reabsorption or an increase in secretion may result in hyperuricosuria. In the proximal tubule, urate reabsorption is mainly mediated by apical URAT1 (SLC22A12) and basolateral GLUT9 (SLC2A9) transporter. OAT4 (SLC22A11) also acts in urate reabsorption in the apical membrane, and its polymorphism is associated with the risk of hyperuricemia. Renal hypouricemia is caused by SLC22A12 or SLC2A9 loss-of-function mutations, and it may be complicated by exercise-induced acute kidney injury. URAT1 and GLUT9 are also drug targets for uricosuric agents. Sodium-glucose cotransporter inhibitors may induce hyperuricosuria by inhibiting GLUT9b located in the apical plasma membrane. Urate secretion is mediated by basolateral OAT1 (SLC22A6) and OAT3 (SLC22A8) and apical ATP-binding cassette super-family G member 2 (ABCG2), NPT1 (SLC17A1), and NPT4 (SLC17A3) transporter in the proximal tubule. NPT1 and NPT4 may be key players in renal urate secretion in humans, and deletion of SLC22A6 and SLC22A8 in mice leads to decreased urate excretion. Dysfunctional variants of ABCG2 inhibit urate secretion from the gut and kidney and may cause gout. In summary, the net result of urate transport in the proximal tubule is determined by the dominance of transporters between reabsorption (URAT1, OAT4, and GLUT9) and secretion (ABCG2, NPT1, NPT4, OAT1, and OAT3).

The Pattern of Allopurinol Prescription Among Chronic Kidney Disease Patients in a Tertiary Care Centre: A Single-Centre Experience.

CONTEXT: Hyperuricemia is prevalent in patients with chronic kidney disease (CKD). Although it is associated with CKD incidence and progression, treating asymptomatic hyperuricemia with uric acid-lowering agents is still debatable. AIM OF WORK: determine the rate of non-classical prescription of allopurinol in CKD patients. SETTINGS AND DESIGN: This was a retrospective study of adult patients prescribed allopurinol with CKD (stages 2-5) in Doctor Soliman Fakeeh Hospital (DSFH) Jeddah, Saudi Arabia, from 1/1/2016 to 1/1/2017. SUBJECTS AND METHODS: Eligible patients were identified from the hospital's pharmacy system and cross-referenced with the electronic health records. Demographic data, laboratory results and indication as recorded by the prescribing physician were extracted. Prescriptions with no indication were categorized based on the uric acid levels. Hyperuricemia was documented as mild (6-10 mg/dL in females and 7-13 mg/dL in males) and severe (>13mg/dL in men and >10mg/dL in women). STATISTICAL ANALYSIS USED: Descriptive statistics (frequencies, percentages). RESULTS: From the 594 identified patients, 464 (78.1%) were males. A third of prescriptions (209/594) had no indication, 43.5% of which (91/209) had no documented uric acid levels, and 16.3% (34/209) had normal levels. Including patients with undocumented indication, 64.2% (381/594) were prescribed allopurinol for hyperuricemia, 86.4% of which (329/381) had mild hyperuricemia, and only 13.6% (52/381) had severe hyperuricemia. Other indications included malignancy-related disorders (6.2%, 37/594), gouty arthritis (5.2%, 31/594), and stones of unknown aetiology (3.4%, 20/594). CONCLUSION: The percentage of allopurinol prescription to patients with CKD without a clear indication in our centre was markedly high. This might increase the risk for side effects with no evidence-based benefits.

The association of dietary inflammatory index with urinary risk factors of kidney stones formation in men with nephrolithiasis.

OBJECTIVE: Inflammation plays a leading role in the pathogenesis of nephrolithiasis. The association of the dietary inflammatory index (DII) with urinary lithogenic factors is unclear. This study aimed to evaluate the relation of DII to urinary risk factors of kidney stones formation. RESULTS: Of 264 participants, 61.4% (n = 162), 72% (n = 190), 74.6% (n = 197), 68.6% (n = 181), and 80.3% (n = 212) had hyperoxaluria, hypercreatininuria, hypercalciuria, hyperuricosuria, hypocitraturia, respectively. There was a significant increasing trajectory in urinary calcium, uric acid, and creatinine as well as a decreasing trend in urinary citrate across tertiles of DII score (all P = ≤0.001). After multivariate adjustment for energy intake, age, physical activity and body mass index, high DII scores were associated with elevated odds of having hypercreatininuria (OR = 2.80, 95%CI: 1.10-7.12, Ptrend = 0.04), hypercalciuria (OR = 7.44, 95%CI: 2.62-21.14, Ptrend ≤ 0.001), hyperuricosuria (OR = 2.22, 95%CI: 1.001-4.95, Ptrend = 0.05), and hypocitraturia (OR = 5.84, 95%CI: 2.14-15.91, Ptrend ≤ 0.001). No association was identified between DII and hyperoxaluria.

The association of Dietary Approaches to Stop Hypertension-style diet with urinary risk factors of kidney stones formation in men with nephrolithiasis.

OBJECTIVE: The relation of the Dietary Approaches to Stop Hypertension (DASH)-style diet to urinary lithogenic factors is unclear. This study aimed to assess the association between adherence to the DASH diet and urinary risk factors of kidney stones formation. METHODS: A total of 264 men apparently with nephrolithiasis, aged 18-89 years, participated in this cross-sectional study. The food item-based DASH diet based on 8 components (nuts and legumes, red and processed meat, low-fat dairy products, sweetened beverages, fruits, vegetables, sodium, and whole grains) and nutrient-based DASH score based on 9 target nutrients (protein, fiber, total fat, saturated fat, cholesterol, sodium, calcium, potassium, and magnesium) were calculated using a food frequency questionnaire. Urine analysis was performed to measure hypercalciuria, hypocitraturia, hyperoxaluria, hyperuricosuria, and hypercreatinuria as study outcomes. Multivariate logistic regression analysis was used to evaluate the relation of DASH diet to urinary factors. RESULTS: After multivariate adjustment, high adherence to the food-based or nutrient-based DASH dietary patterns was significantly associated with lower odds for hypercreatininuria, hypocitraturia, and hypercalciuria. Higher nutrient-based DASH diet scores were related to lower odds of hyperuricosuria and moderate adherence to the food-based DASH score increased odds for hyperoxaluria. Moreover, expect for "Nuts and legumes" and sodium, other components of DASH diet were significantly related to urinary lithogenic factors. CONCLUSION: Adherence to the DASH diet may be a strong preventive approach to decrease urinary risk factors of kidney stone formation.

Allopurinol prescription patterns among patients in a Saudi tertiary care centre.

OBJECTIVE: Physicians frequently prescribe allopurinol for uric acid deposition disorders. However, reports have emerged of the inappropriate use and overprescription of allopurinol. We conducted this study to determine the rate of inappropriate prescription of allopurinol in a Saudi institution. METHODS: This cross-sectional descriptive study was conducted on all adult patients who had been prescribed allopurinol in Doctor Soliman Fakeeh Hospital Jeddah KSA. Demographic data and laboratory results were retrieved from patients' electronic health records (EHR). We considered valid indications of allopurinol as significant hyperuricemia (>13 mg/dL in men and >10 mg/dL in women), confirmed gout, hyperuricosuria of more than 1100 mg/day, uric acid stones or recurrent calcium oxalate kidney stones, malignancy, and haemolysis. The possible valid indications were unconfirmed gout and unconfirmed type of kidney stones, whereas no documented indication or insignificant hyperuricemia was considered as an invalid indication. RESULTS: We included 1978 patients in this study. The cohort was composed of 76.4% men and 23.6% women. The mean ± standard deviation of age of this patient cohort was 53 and 4 months ± 15 years. The mean ± standard deviation of duration since the first prescription was 1.53 ± 2.2 years. Physicians prescribed allopurinol without a valid indication in 1539 patients (77.8%). More than a third of the patients (39%) did not have a documented indication and 38.8% were prescribed allopurinol for insignificant hyperuricemia. CONCLUSION: This study revealed a markedly high number of allopurinol prescriptions without a clear indication in our centre. This approach may potentially expose patients to serious side effects of allopurinol without added benefits.

Hyperuricosuria, hematuria, and novel bladder images with IgA nephropathy.

Episodic (recurrent) macroscopic hematuria in patients with IgA nephropathy is usually associated with a benign prognosis, although some patients experience a transient fall in glomerular filtration rate during the episodes. We present a 15-year-old girl with mild IgA nephropathy who had multiple episodes of macroscopic hematuria associated with severe but transient decreases in estimated glomerular filtration rate, low levels of serum uric acid, and marked increases in fractional excretion of uric acid. Ultrasound studies showed marked inflammatory changes in the bladder, especially involving the trigone. Cystoscopic findings were consistent with these changes. We hypothesize that the macroscopic hematuria may have resulted, at least in part, from hyperuricosuria causing acute irritation of the bladder mucosa in the trigone area.

Hyperuricosuric calcium urolithiasis.

Hyperuricosuric calcium urolithiasis is a condition of mixed calcium oxalate stones characterized by hyperuricosuria either in isolation or in conjunction with other risk factors for calcium oxalate stones such as hypercalciuria, hyperoxaluria, and hypocitraturia. There are three proposed physicochemical models of pathogenesis where urate in its crystalline phase via heterogeneous nucleation, in its colloidal phase via removal of crystallization inhibitors, and in solution via precipitation crystallization, can all increase propensity to calcium oxalate precipitation. Regardless of the model, the phenomenologic observation of urate increasing calcium oxalate precipitation appears solid. Another supporting factor are retrospective data analysis and prospective trials showing uric acid lowering reduces stones events in hyperuricosuric calcium stone formers. Due to the heterogeneity of pathogenesis of calcium oxalate stones in the unselected stone-formers, association cannot be demonstrated between uric acid excretion rate and risk of kidney stone the general population. In calcium oxalate stoners with isolated hyperuricosuria or hyperuricosuria in combination with other calcium stone risks where treatment of these traditional risks fails to reduce stone formation, urate acid lowering should be cautiously attempted. More refinement of pathogenic models and prospective controlled trials in phenotypically defined subgroups of subjects with calcium oxalate urolithiasis will be informative.

Impact of non-adherence on the safety and efficacy of uric acid-lowering therapies in the treatment of gout.

AIMS: Dual-urate-lowering therapy (ULT) with xanthine oxidase inhibitor and uricosuric medications is a treatment option for severe gout. Uricosuric agents can cause hyperuricosuria, a risk factor for nephrolithiasis and acute uric acid nephropathy. The aims of the present study were to simulate the relationship between suboptimal drug adherence and efficacy, and to quantify the risk of hyperuricosuria in gout patients receiving mono- and dual-ULTs. METHODS: The impact of poor medication adherence was studied using two-compartment pharmacokinetic (PK) models based on published evidence, and a semi-mechanistic four-compartment pharmacodynamic (PD) model. The PKPD model was used to simulate mono and dual-ULT in gout patients with either under-excretion (lowered clearance) or overproduction of uric acid, with suboptimal adherence modelled as either a single drug holiday of increasing duration or doses taken at random. RESULTS: Simulation results showed a surge in urinary uric acid occurring when dosing is restarted following missed doses. For under-excreters taking a 20-day drug holiday, the addition of 200 mg (or 400 mg) lesinurad to 80 mg febuxostat increased the percentage of patients experiencing hyperuricosuria from 0% to 1.4% (or 3.1%). In overproducers, restarting ULTs following drug holidays of more than 5 days leads to over 60% of patients experiencing hyperuricosuria. CONCLUSIONS: Suboptimal medication adherence may compromise the safety and efficacy of mono- and dual-ULTs, especially in patients with gout resulting from an overproduction of uric acid. Clinicians and pharmacists should consider counselling patients with respect to the risks associated with partial adherence, and offer interventions to improve adherence or tailor treatments, where appropriate.

Efficacy of potassium polycitrate on renal stone and microlithiasis predisposed by metabolic disorders.

BACKGROUND: According to high prevalence of renal stone in children, we evaluated the efficacy of treatment with potassium citrate and its correlation with metabolic disorders in children less than two years of age with renal stone and microlithiasis. METHODS: In this cross- sectionaly study, 100 patients (less than 2 years old) with renal stone or microlitiasis were evaluated for metabolic disorders. They were treated with potassium citrate and followed-up by ultrasonography every 3 months. Then response to treatment was evaluated according to the fresence metabolic disorders (A p-alue<0.05 was significant). RESULTS: According to this study, hyperuricosuria and hypercalciuria were the two major metabolic disorders (40-33%). Seventy three patients had complete response, and also there as not a significant difference (p<0.05) in the efficacy of treatment due to types of metabolic disorders. There was significant difference between relative response to treatment in children who had metabolic disorders and patient without any metabolic disorders. CONCLUSION: Based on our results the use of potassium citrate in all children less than 2 years with renal stone or microlithiasis especially those with metabolic disorders, are recommended.

Uric acid, an important screening tool to detect inborn errors of metabolism: a case series.

BACKGROUND: Uric acid is the metabolic end product of purine metabolism in humans. Altered serum and urine uric acid level (both above and below the reference ranges) is an indispensable marker in detecting rare inborn errors of metabolism. We describe different case scenarios of 4 Sri Lankan patients related to abnormal uric acid levels in blood and urine. CASE 1: A one-and-half-year-old boy was investigated for haematuria and a calculus in the bladder. Xanthine crystals were seen in microscopic examination of urine sediment. Low uric acid concentrations in serum and low urinary fractional excretion of uric acid associated with high urinary excretion of xanthine and hypoxanthine were compatible with xanthine oxidase deficiency. CASE 2: An 8-month-old boy presented with intractable seizures, feeding difficulties, screaming episodes, microcephaly, facial dysmorphism and severe neuro developmental delay. Low uric acid level in serum, low fractional excretion of uric acid and radiological findings were consistent with possible molybdenum cofactor deficiency. Diagnosis was confirmed by elevated levels of xanthine, hypoxanthine and sulfocysteine levels in urine. CASE 3: A 3-year-10-month-old boy presented with global developmental delay, failure to thrive, dystonia and self-destructive behaviour. High uric acid levels in serum, increased fractional excretion of uric acid and absent hypoxanthine-guanine phosphoribosyltransferase enzyme level confirmed the diagnosis of Lesch-Nyhan syndrome. CASE 4: A 9-year-old boy was investigated for lower abdominal pain, gross haematuria and right renal calculus. Low uric acid level in serum and increased fractional excretion of uric acid pointed towards hereditary renal hypouricaemia which was confirmed by genetic studies. CONCLUSION: Abnormal uric acid level in blood and urine is a valuable tool in screening for clinical conditions related to derangement of the nucleic acid metabolic pathway.

The role of the 24-h urine collection in the management of nephrolithiasis.

Recurrent nephrolithiasis is a common chronic condition that is often preventable with dietary modification and pharmacologic therapy. Patients with recurrent kidney stones should have a metabolic evaluation, consisting of radiologic studies to assess stone burden, crystallographic stone analysis, and laboratory studies including standard serum chemistries and 24 h urine collection(s). This article focuses on the interpretation of urine chemistries to identify lithogenic risk factors and assess the contribution of diet to the formation of kidney stones.

Medical and alternative therapies in urinary tract stone disease.

Nephrolithiasis is a serious problem for both patients and the health system. Recurrence stands out as a significant problem in urinary system stone disease, the prevalence of which is increasing gradually. If recurrence is not prevented, patients may go through recurrent operations due to nephrolithiasis. While classical therapeutic options are available for all stone types, the number of randomized controlled studies and extensive meta-analyses focusing on their efficiency are inadequate. Various alternative therapeutic options to these medical therapies also stand out in recent years. The etiology of urolithiasis is multifactorial and not always related to nutritional factors. Nutrition therapy seems to be useful, either along with pharmacological therapy or as a monotherapy. General nutrition guidelines are useful in promoting public health and developing nutrition plans that reduce the risk or attenuate the effects of diseases affected by nutrition. Nutrition therapy involves the evaluation of a patient's nutritional state and intake, the diagnosis of nutrition risk factors, and the organization and application of a nutrition program. The main target is the reduction or prevention of calculus formation and growth via decreasing lithogenic risk factors and increasing lithogenic inhibitors in urine. This review focuses briefly on classical medical therapy, along with alternative options, related diets, and medical expulsive therapy.

Trastornos metabólicos renales en pacientes cubanos adultos con litiasis urinarias / Renal metabolic disturbances in Cuban adult patients with urinary lithiasis

Introducción: las litiasis urinarias constituyen un problema de salud. La recurrencia de ellas hace necesario implementar estrategias preventivas, para lo cual es indispensable conocer la frecuencia de los diferentes trastornos metabólicos renales. Objetivos: identificar los disturbios metabólicos más frecuentes en la enfermedad litiásica urinaria y la posible relación de estos con características de los pacientes. Métodos: estudio observacional analítico, transversal. Se estudiaron 3 655 pacientes adultos con litiasis urinaria, que se realizaron estudio metabólico renal en el Instituto de Nefrología entre los años 2003 y 2009. Las determinaciones analíticas fueron realizadas por técnica espectrofotométrica, según las normas del servicio. Toda la información se procesó mediante el paquete estadístico SPSS versión 15.0. Se utilizó la técnica de análisis de distribución de frecuencias...

Introduction: the recurrence of urinary lithiasis is a health problem needing the implementation of preventive strategies, thus knowing the frequency of the different renal metabolic disorders is essential. Objectives: To identify the most common metabolic disorders in urinary lithiasic disease and their relationship with patient characteristics. Methods: an analytical, cross-sectional study was conducted in 3655 adult patients with urolithiasis. A renal metabolic study was conducted at the Institute of Nephrology from 2003 to 2009. The analytical determinations were performed by spectrophotometric technique according to the standards of service. All information is processed using SPSS version 15.0. The technique of frequency distribution analysis was used. Relationships between variables were identified by the test of independence. Results: The main metabolic disorders found were: hyperuricemia (48.2 percent), hypercalciuria (45.1 percent), and urinary tract infection (16.2 percent). Hypercalciuria and hyperuricosuria were less frequent in subjects older than 42 years (p= 0.01). Hypercalciuria, hyperoxaluria and hyperuricosuria were more frequent in men (p= 0.00), while hypocitraturia was more frequent in women (p= 0.04). Hyperuricosuria was found more frequently in overweight and obese patients (p= 0.00), and hyperoxaluria was more frequent among overweight subjects (p= 0.01). Conclusions: In patients with renal lithiasis the most common metabolic disorders are hyperuricemia, hypercalciuria, and urinary tract infection. All subjects younger than 43 years suffered hypercalciuria and hyperuricosuria. Men have higher frequency of hypercalciuria, hyperuricosuria and hyperoxaluria. Women have higher frequency of hypocitraturia. The frequency of submission of hyperoxaluria, hyperuricosuria and hypocitraturia is related to the nutritional status of these subjects(AU)

Trastornos metabólicos renales en pacientes cubanos adultos con litiasis urinarias / Renal metabolic disturbances in Cuban adult patients with urinary lithiasis

INTRODUCCIÓN: las litiasis urinarias constituyen un problema de salud. La recurrencia de ellas hace necesario implementar estrategias preventivas, para lo cual es indispensable conocer la frecuencia de los diferentes trastornos metabólicos renales. OBJETIVOS: identificar los disturbios metabólicos más frecuentes en la enfermedad litiásica urinaria y la posible relación de estos con características de los pacientes. MÉTODOS: estudio observacional analítico, transversal. Se estudiaron 3 655 pacientes adultos con litiasis urinaria, que se realizaron estudio metabólico renal en el Instituto de Nefrología entre los años 2003 y 2009. Las determinaciones analíticas fueron realizadas por técnica espectrofotométrica, según las normas del servicio. Toda la información se procesó mediante el paquete estadístico SPSS versión 15.0. Se utilizó la técnica de análisis de distribución de frecuencias. Las relaciones entre las variables se identificaron mediante el test de independencia. RESULTADOS: los principales trastornos metabólicos encontrados fueron: hiperuricemia (48,2 %), hipercalciuria (45,1 %) e infección del tracto urinario (16,2 %). La hipercalciuria y la hiperuricosuria fueron menos frecuentes en los sujetos mayores de 42 años (p= 0,01). La hipercalciuria, la hiperoxaluria y la hiperuricosuria resultaron más frecuentes en los hombres (p= 0,00), mientras la hipocitraturia tuvo mayor frecuencia en las mujeres (p= 0,04). La hiperuricosuria se encontró con mayor frecuencia en pacientes sobrepesos y obesos (p= 0,00), y la hiperoxaluria fue más frecuente entre los sobrepesos (p= 0,01). CONCLUSIONES: en los pacientes con litiasis renal los trastornos metabólicos más frecuentes son hiperuricemia, hipercalciuria e infección del tracto urinario. Los menores de 43 años tienen más hipercalciuria e hiperuricosuria. Los hombres tienen mayor frecuencia de hipercalciuria, hiperoxaluria e hiperuricosuria y las mujeres, de hipocitraturia. La frecuencia de presentación de hiperoxaluria, hiperuricosuria e hipocitraturia se encuentra relacionada con el estado nutricional de los sujetos.

INTRODUCTION: the recurrence of urinary lithiasis is a health problem needing the implementation of preventive strategies, thus knowing the frequency of the different renal metabolic disorders is essential. OBJECTIVES: To identify the most common metabolic disorders in urinary lithiasic disease and their relationship with patient characteristics. METHODS: an analytical, cross-sectional study was conducted in 3655 adult patients with urolithiasis. A renal metabolic study was conducted at the Institute of Nephrology from 2003 to 2009. The analytical determinations were performed by spectrophotometric technique according to the standards of service. All information is processed using SPSS version 15.0. The technique of frequency distribution analysis was used. Relationships between variables were identified by the test of independence. RESULTS: The main metabolic disorders found were: hyperuricemia (48.2%), hypercalciuria (45.1%), and urinary tract infection (16.2 %). Hypercalciuria and hyperuricosuria were less frequent in subjects older than 42 years (p= 0.01). Hypercalciuria, hyperoxaluria and hyperuricosuria were more frequent in men (p= 0.00), while hypocitraturia was more frequent in women (p= 0.04). Hyperuricosuria was found more frequently in overweight and obese patients (p= 0.00), and hyperoxaluria was more frequent among overweight subjects (p= 0.01). CONCLUSIONS: In patients with renal lithiasis the most common metabolic disorders are hyperuricemia, hypercalciuria, and urinary tract infection. All subjects younger than 43 years suffered hypercalciuria and hyperuricosuria. Men have higher frequency of hypercalciuria, hyperuricosuria and hyperoxaluria. Women have higher frequency of hypocitraturia. The frequency of submission of hyperoxaluria, hyperuricosuria and hypocitraturia is related to the nutritional status of these subjects.