Background: Balkan nephropathy (BEN) is an environmental form of aristolochic acid nephropathy (AAN) strongly associated with upper urinary tract urothelial carcinoma (UTUC). Clinical diagnosis remains challenging, and misclassification is frequent. The study reassessed BEN diagnoses in kidney transplant recipients from rural farming areas who did not undergo prophylactic bilateral nephroureterectomy and evaluated post-transplant outcomes. Methods: In this retrospective single-centre study, we analysed 12 kidney transplant recipients from rural Balkan farming regions. BEN diagnoses were reevaluated according to international consensus criteria. Key endpoints included patient and graft survival, post-transplant clinical course, and UTUC characteristics. Results: Upon reassessment, three of the six patients initially diagnosed with BEN were reclassified as having BEN. Among the remaining six patients, four were reclassified as having sporadic BEN. Overall, only 33% of patients had a diagnosis concordant with their admission records. During a median follow-up of 6.8 years (IQR 2.1–15.8), UTUC developed in seven out of 12 patients. The UTUC cases were predominantly high-grade and multifocal, and they were identified as the leading cause of death. Five-year patient and graft survival rates were 71% and 100%, respectively. Conclusions: BEN is frequently misdiagnosed or misclassified in kidney transplant candidates from rural farming areas. Despite excellent graft survival, the high incidence of post-transplant urothelial carcinoma underscores the necessity of accurate diagnosis and the consideration of prophylactic bilateral nephroureterectomy. Lifelong intensive surveillance is essential not only for patients from established BEN regions but also for individuals from other rural farming areas at risk for sporadic BEN.

Background: There are conflicting reports on the association of socioeconomic (SES) characteristics and lifestyle with salt and potassium intake as well as with the sodium-to-potassium (Na/K) ratio. This paper examined how SES status and lifestyle habits affect salt, potassium intake, and the Na/K ratio in adults. Methods: Adults subjects (random sample) from the EH-UH 2 nationwide study with valid 24 h urine samples were included in these analyses. We used a questionnaire which included SES and questions related to lifestyle. Salt and potassium levels were measured using a 24 h urine collection. Results: A low level of professional qualification and education are important predictors of high salt and low potassium intake. SES affects salt intake more than potassium intake. Processed meat was the most important determinant of high salt intake. It significantly affected potassium intake, but this was not relevant due to a poor Na/K ratio. Non-smoking status was related to high daily salt and potassium intake, but with no significantly positive impact on Na/K ratio. Former smokers swapped one unhealthy habit for another, such as overeating or consuming too much salt. The Adriatic/Mediterranean diet, represented in this study with frequent olive oil and fish consumption, was related to more favourable salt and potassium intake and a better Na/K ratio. Targets of daily salt and potassium intake, as well as of Na/K ratio were achieved in a very low proportion of the population regardless of SES, lifestyle and behaviour. Conclusions: Our results emphasize the need for public-health strategies that consider both diet and individual characteristics to address nutritional inequalities and promote healthier eating habits. Targeted nutrition programmes for lower SES groups should emphasize salt reduction and encourage potassium-rich diets, thus reducing health imparities and the burden of diet-related chronic diseases. The prevention strategy should be more proactive and specifically designed for the food (meat) industry. A more holistic approach should be taken for smokers when quitting smoking is necessary, the whole population should be educated to change habits toward the Adriatic diet pattern, and the government should make olive oil and fish more affordable to all citizens, particularly to those with poor SES.

Although significant progress has been made in reducing salt consumption over the past decade, most Croatian adults still exceed the recommended intake. This study aimed to identify demographic, socioeconomic, lifestyle, and clinical factors associated with high salt intake in the general adult population of Croatia. We included a random sample of 1067 adults with reliable 24-h urine samples. A structured questionnaire was used to collect sociodemographic, lifestyle, and clinical data. Anthropometric and blood pressure (BP) measurements were performed. Laboratory analyses included the measurement of sodium, potassium, and creatinine in adequate 24-h urine samples, as well as relevant cardiometabolic and kidney-related biomarkers. Participants consuming > 10 g/day of salt were older and had higher systolic blood pressure, fasting glucose, serum uric acid, and triglyceride levels, lower HDL cholesterol levels, and greater BMI. High salt intake was more common among men, ex-smokers, participants with diabetes, and those with lower socioeconomic status (SES). In multinomial logistic regression analysis, male sex, diabetes, higher systolic BP, more frequent processed meat consumption, lower fish consumption, residence outside the Adriatic region, and higher ePWV were associated with high salt intake. High salt intake was associated with lower socioeconomic status, residence in rural and continental areas, obesity, former smoking, and less favorable dietary patterns. Conversely, lower salt intake was associated with residence in the Adriatic region and dietary patterns characterized by more frequent consumption of fish and olive oil.