INTRODUCTION Pediatric urinary lithiasis (urolithiasis) is an important health issue linked to urinary metabolic disorders. In the United States alone, annual costs associated with urolithiasis are $229 million for hospital admissions and $146 million for emergency care.

OBJECTIVE Identify urinary metabolic disorders in Cuban pediatric patients with urolithiasis and better understand the relationship of age, demographic and anthropometric variables to urinary metabolic disorders strongly associated with urolithiasis.

METHODS We carried out a descriptive, cross-sectional study. The study universe was comprised of Cuban patients aged 2 to 19 years with urinary lithiasis who underwent renal metabolic studies at the Dr Abelardo Buch López Nephrology Institute in Havana, Cuba, from 2008 through 2019. All data were obtained from reports of the aforementioned metabolic studies. We collected the following variables: age, sex, nutritional status, urinary volume, plasma and urinary creatine concentrations; and calcium, uric acid, oxalate and citrate urinary excretions collected during a 24-hour period. We included results of urinary cystine tests and urine mini-cultures. We obtained frequency distributions for categorical and qualitative variables and calculated means and standard deviations for quantitative variables. We also evaluated homogeneity of metabolic disorders between children and adolescents.

RESULTS We studied 1592 pediatric patients, of whom 67.7% (1078/1592) were adolescents. The main metabolic disorders included hypercalciuria (39.1%; 622/1592), decreased urinary flow (22.4%; 357/1592) and hypocitraturia (18.2%; 289/1592). Hypercalciuria, hypocitraturia and hyperoxaluria were more common in children, while decreased urinary flow and hyperuricosuria were more common in adolescents. Hyperuricosuria was more frequent in male patients (6.3%; 40/639 vs. 1.8%; 8/439) and had the greatest impact on lithogenesis. Hypercalciuria was more frequent in undernourished children (62.5%; 30/48) than in overweight children (21.7%; 10/46), or those with obesity (33.3%; 15/45).

CONCLUSIONS The main metabolic disorders among Cuban pediatric patients with urinary lithiasis are: hypercalciuria, decreased urinary flow and hypocitraturia. Hypercalciuria, hypocitraturia and hyperoxaluria are more common in children, and decreased urinary flow and hyperuricosuria are more common in adolescents. Identifying urinary metabolic disorders facilitates formulation of treatment plans tailored to decreasing the likelihood of urolithiasis.

KEYWORDS Pediatrics, urolithiasis, urinary lithiasis, hypercalciuria, urine, Cuba

At first, COVID-19 was thought to be primarily a respiratory disease, progressing in some patients to serious respiratory symptoms, pneumonia, severe respiratory distress syndrome and even death. Later analysis revealed entire systems were compromised, affecting other vital organs, including the kidneys, and a correlation was observed between chronic kidney disease (CKD) and COVID-19 severity.[1,2] This […]

In El Salvador, chronic kidney disease had reached epidemic proportions towards the end of this century’s first decade. In 2011–2012, the Ministry of Health reported it was the leading cause of hospital deaths in men, the fifth in women, and the third overall in adult hospital fatalities. Farming was the most common occupation among men in dialysis (50.7%). By 2017, chronic kidney disease admissions had overwhelmed hospital capacity. In 2009, El Salvador’s Ministry of Health, Cuba’s Ministry of Public Health and PAHO launched a cooperative effort to comprehensively tackle the epidemic. The joint investigations revealed a total prevalence of chronic kidney disease in the adult population of farming communities higher than that reported internationally (18% vs.11%–14.8%), higher in men than in women (23.9% vs 13.9%) and higher in men who were farmers/farmworkers than in men who were not (31.3% vs. 14.8%). The disease was also detected in children. An association was found between chronic kidney disease and exposure to agrochemicals (OR 1.4–2.5). In 51.9% of all chronic kidney disease cases, traditional causes (diabetes, hypertension, glomerulopathies, obstructive nephropathies and cystic diseases) were ruled out and the existence of a particular form of chronic kidney disease of nontraditional etiology was confirmed (whose initial cases were reported as early as 2002). In the patients studied, functional alterations and histopathologic diagnosis confirmed a chronic tubulointerstitial nephritis; most presented with neurosensory hearing loss, altered tendon reflexes and tibial artery damage. The main results of this cooperation were the epidemiologic, physiopathologic, clinical and histopathologic characterization of chronic kidney disease of nontraditional etiology. This characterization facilitated case definition for the epidemic and led to the hypothesis of systemic toxicity from agrochemicals (e.g., paraquat, glyphosate), which particularly affect the kidneys and to which farmers/farmworkers (who may also become dehydrated in the fields) are most exposed. The research thus also laid the foundations for design of comprehensive intersectoral government actions to reduce cases and put an end to the epidemic. KEYWORDS Chronic kidney disease, chronic renal failure, tubulointerstitial nephritis, epidemiology, histopathology, international cooperation, agrochemicals, environmental pollutants, noxae, and pesticides, occupational health, PAHO; El Salvador, Cuba