Genetic lithiasis: the contribution of infrared spectroscopy as a diagnostic tool

Abstract

Lithiasis of genetic origin is caused by rare hereditary pathologies, in which the accumulation of compounds in urine is associated with the formation of recurrent urinary stones, generating detrimental consequences for the patient. Fourier transform infrared spectroscopy (FTIR) is a reference methodology in the analysis and unambiguous identification of compounds present in urinary calculi. The aim of this study was to describe the use of the FTIR technique and its importance as a diagnostic tool for genetic lithiasis in Paraguay. The design was observational descriptive and was analyzed by FTIR urinary stones from 740 patients with demographic and clinical data. Of the total, 104 were children and 636 adults. Stones related to genetic pathologies were identified in 7 (0,9%) patients, 5 of cystine and 2 of xanthine, allowing the definitive diagnosis of cystinuria and xanthinuria, respectively. The most common location of the stones was the kidney, the most frequent form of removal was surgery and the largest had 24x19x13 mm, considered as voluminous. Were submitted stones of the first episode of 5 patients and recurrence of 2 patients. The accurate diagnosis of these genetic lithiases was possible by means of the FTIR technique, which allowed knowledge of the underlying cause and to guide the choice of specific therapeutic measures aimed at decreasing the risk of recurrence and to improve the standard of living of patients.