Use of the probability of stone formation (PSF) score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers

Introduction The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers. Materials and Methods Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment. Results At baseline, 20 of the 26 patients (77%) had a high PSF score (> 0.5). Of the 26 patients, 17 (65%) showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42%) changed from a high risk (PSF > 0.5) to a low risk (PSF < 0.5) and 6 patients reduced their risk score but did not change risk category. Six (23%) patients remained in a high risk category (> 0.5) during both assessments. Conclusions The PSF score reduced following medical treatment in the majority of patients in this cohort. .

Doença de Crohn e cálculo renal: muito mais que coincidência? / Crohn’s disease and kidney stones: much more than coincidence?

RACIONAL: A doença de Crohn é uma doença inflamatória intestinal que pode estar associada a várias complicações e manifestações que são secundárias ao processo inflamatório de base. Em aproximadamente 30 por cento dos pacientes têm sido encontradas manifestações extra-intestinais. A nefrolitíase é uma delas e a formação de cálculos é mais comum nestes pacientes do que na população em geral, principalmente cálculos de oxalato de cálcio. OBJETIVOS: Avaliar os fatores metabólicos urinários potencialmente envolvidos na formação de cálculos renais em pacientes com doença de Crohn. MÉTODOS: Foram avaliados 29 pacientes com doença de Crohn atendidos no Ambulatório de Doenças Inflamatórias do Hospital de Clínicas da Universidade Estadual de Londrina, PR, no período de janeiro a dezembro de 2004. A avaliação metabólica incluiu medidas séricas e urinárias de substâncias relacionadas à litíase renal, ultra-sonografia de rins e vias urinárias e cálculo da supersaturação urinária para o oxalato de cálcio, ácido úrico e fosfato de cálcio. RESULTADOS: Dos 29 pacientes avaliados, 65,5 por cento eram do sexo feminino e 34,5 por cento do masculino. As principais alterações metabólicas urinárias encontradas foram 72,41 por cento de hipocitratúria, 41,4 por cento de hipomagnesiúria, 13,6 por cento de hiperoxalúria e 17,24 por cento de baixo volume urinário. Foram encontrados cálculos renais em 13 pacientes (44,8 por cento). Os pacientes submetidos a cirurgia intestinal, com ressecção ileal, apresentaram alterações na saturação urinária de oxalato e fosfato. Para a comparação das médias, utilizou-se o teste de Mann-Whitney e para determinar a associação entre as variáveis foi utilizado o teste do Qui-quadrado ou o teste exato de Fisher com um nível de significância de 5 por cento. CONCLUSÃO: A freqüência de pacientes com cálculos renais foi maior que a encontrada na população geral e acima do descrito em trabalhos similares. As alterações encontradas como...

BACKGROUND: Crohn’s disease is an inflammatory bowel disease associated with a wide variety of complications and manifestations secondary to the effects of underlie inflammatory process. In about 30 percent of the patients with Crohn’s disease can be found extra-intestinals symptoms. Nephrolithiasis is one of them and the appearance of kidney stones, mainly of oxalate of calcium, is more common in these patients than in general population. AIM: To evaluate urinary metabolic factors potentially involved in renal stones formation on patients with Crohn’s disease. METHODS: We evaluated 29 patients with Crohn’s disease followed in the Outpatient Bowel Inflammatory Disease Clinics of State University Hospital, Londrina, PR, Brazil, from January to December of 2004. The metabolic evaluation included measured of blood and urine substances related to renal stones formation, kidneys, ureters and bladder ultrassonography and calculation of urinary supersaturation for calcium oxalate, uric acid and calcium phosphate. RESULTS: Twenty-nine of the evaluated patients were female or 65.5 percent and 34.5 percent were males. Among the metabolic urinary studied, we identified the following potential disturbances associated with nephrolithiasis: hypocitraturia in 21 patients (72.4 percent), hypomagnesuria in 12 (41.4 percent), hyperoxaluria in 4 (13.6 percent) and urinary volume low in 5 (17.2 percent). Renal stones were identified in 13 patients (44.8 percent). Oxalate urinary excretion was higher in patients submitted to bowel surgery and also in patients with ileum resection. The urinary supersaturation of calcium oxalate and brushita in patients with bowels surgery was higher than the other patients not submitted to any surgery. Data to compare patients who underwent to surgery or not were analyzed by Mann-Whitney test (U test), and Qui-square test or the accurate test of Fisher have been used to determine variables association. For all tests 5 percent...

Measurements of urinary state of saturation with respect to calcium oxalate and brushite (CaHPO4.2H2O) in renal stone formers.

Urinary supersaturation with respect to calcium oxalate and/or brushite (CaHPO4.2H2O) is critical for the formation of calcium stones. The aim of this study is to use concentration product ratio (CPR) as a tool to assess the state of urine saturation with respect to calcium oxalate and brushite. One 24-h urine specimen from each of 16 healthy city dwellers (GI), 18 healthy villagers (GII) and 28 villagers with renal stones (GIII) was collected and analyzed for calcium, sodium, potassium, phosphate, uric acid, citrate and oxalate. The CPRs of calcium and oxalate and of calcium and phosphate before and after equilibration of the urine with the corresponding seeding crystals were also determined. Urinary volume and the excretion rate of calcium, potassium, uric acid, citrate and oxalate of GII and of sodium, phosphate, uric acid and citrate of GIII were significantly less than those of GI. The CPRs for calcium oxalate and brushite were 2.9 +/- 0.3 and 1.7 +/- 0.2 for GI, 2.7 +/- 0.2 and 1.3 +/- 0.1 for GII and 2.5 +/- 0.2 and 1.1 +/- 0.1 for GIII, respectively. The CPR values indicated that urine of all groups was generally supersaturated with respect to calcium oxalate salt (CPRs were above 1) and were not different among the groups. With regard to brushite, urine was also supersaturated but the state of supersaturation was less than that of calcium oxalate. Furthermore, instead of being supersaturated, brushite in many urine specimens of GIII was undersaturated and its mean CPR was even significantly less than that of GI (P less than 0.01).