RESUMEN
INTRODUCTION: The percutaneous kidney biopsy (PKB) is an essential tool in nephrology; small kidney size has been a relative contraindication to PKB and there is limited data on the safety and utility of performing PKB in this setting. Our aim was to describe the complications of PKB in small kidneys and to assess if kidney biopsy results have an impact on medical decisions and outcomes. METHODS: This was a retrospective, descriptive, and observational study. Patients older than 16 years of age with a decreased kidney size (≤8 cm) and undergoing PKB of native kidneys from July 2019 to December 2022 were included. RESULTS: Twenty-five patients were included, 19 women and 6 men. The mean age was 42.3 ± 18.04. The mean kidney length was 7.56 ± 0.33 and the mean width was 4.2 cm. All patients received only 1 puncture, obtaining an average of 12 glomeruli. The mean blood urea nitrogen and serum creatinine were 36 mg/dL and 1.94 mg/dL, respectively and the mean Hgb (hemoglobin) was 12.87 ± 2.81 g/dL. Minor complications occurred in 5 patients, perirenal hematoma in 3 patients, hematuria in 1 patient, and hematoma plus hematuria in 1 patient. Histological examination showed FSGS, lupus nephritis, other Glomerular disease, crescentic glomerulonephritis, and tubulointerstitial nephritis in 36%, 20%, 16%, 16%, and 12% of the cases, respectively. Biopsy resulted in management modification in 64% of cases. In a bivariate analysis, kidney size was not associated with higher complication rates. CONCLUSIONS: PKB in small kidneys is a feasible and safe procedure when properly planned, providing an adequate sample in all cases, with an insignificant number of minor complications, and that is clinically relevant.
RESUMEN
BACKGROUND: The association between congenital heart disease and chronic kidney disease is well known. Various mechanisms of kidney damage associated with congenital heart disease have been established. The etiology of kidneydisease has commonly been considered to be secondary to focal segmental glomerulosclerosis (FSGS), however, this has only been demonstrated in case reports and not in observational or clinical trials. AIM: To identify baseline and clinical characteristics, as well as the findings in kidney biopsies of patients with congenital heart disease in our hospital. METHODS: This is a retrospective observational study conducted at the Nephrology Department of the National Institute of Cardiology "Ignacio Chávez". All patients over 16 years old who underwent percutaneous kidney biopsy from January 2000 to January 2023 with congenital heart disease were included in the study. RESULTS: Ten patients with congenital heart disease and kidney biopsy were found. The average age was 29.00 years ± 15.87 years with pre-biopsy proteinuria of 6193 mg/24 h ± 6165 mg/24 h. The most common congenital heart disease was Fallot's tetralogy with 2 cases (20%) and ventricular septal defect with 2 (20%) cases. Among the 10 cases, one case of IgA nephropathy and one case of membranoproliferative glomerulonephritis associated with immune complexes were found, receiving specific treatment after histopathological diagnosis, delaying the initiation of kidney replacement therapy. Among remaining 8 cases (80%), one case of FSGS with perihilar variety was found, while the other 7 cases were non-specific FSGS. CONCLUSION: Determining the cause of chronic kidney disease can help in delaying the need for kidney replacement therapy. In 2 out of 10 patients in our study, interventions were performed, and initiation of kidney replacement therapy was delayed. Prospective studies are needed to determine the usefulness of kidney biopsy in patients with congenital heart disease.