Correlations between metabolic alkalemia and nephrolithiasis: retrospective study

• Grant number: 17/03029-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): September 01, 2017
• Effective date (End): August 31, 2018
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Claudia Maria de Barros Helou
• Grantee: Renato Vianna Marotta Starek
• Host Institution: Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

The prevalence of nephrolithiasis due to idiopathic hypercalciuria is high. As thiazides are drugs that reduce the urinary excretion of calcium your prescription is often recommended in these cases. However, thiazides increase the urinary excretion of chloride and therefore may cause chloride-responsive metabolic alkalemia. The aim of the present study is to verify the incidence of metabolic alkalemia in patients with nephrolithiasis. In addition, whether the thiazides treatment is the main cause in these cases. We will analyze the medical records of the patients attending in renal lithiasis outpatient clinic of Instituto Central do Hospital das Clínicas da Faculdade de Medicina da USP (ICHC-FMUSP) from 2014 until now. First, we will select the medical records of the patients that show in their blood gas analysis the values of pH equal or above 7.46 and a concentration of bicarbonate equal or above 26 meq/l. After, we will collect the data regarding gender, age, etiological diagnosis of nephrolithiasis, use of thiazide and other drugs, plasma and urinary concentrations of sodium, potassium, chlorine, calcium, magnesium, phosphorus and citrate. Finally, we will classify the data into two sub-groups of patients according to their renal function. For this purpose, we will apply the MDRD and EPI-CKD equations. Group I - patients with glomerular filtration rate above 60 ml / min; Group II - patients with glomerular filtration rate less than 60 ml / min. (AU)