Nephron最新文献

Introduction: C-reactive protein-to-albumin ratio (CAR) is a prognostic marker in various diseases that represents patients' inflammation and nutritional status. Here, we aimed to investigate the prognostic value of CAR in critically ill patients with severe acute kidney injury requiring continuous renal replacement therapy (CRRT).

Methods: We retrospectively collected data from eight tertiary hospitals in Korea from 2006-2021. The patients were divided into quartiles according to CAR levels at the time of CRRT initiation. Cox regression analyses were performed to investigate the effect of CAR on in-hospital mortality. The mortality prediction performance of CAR was evaluated using the area under the curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Results: In total, 3,995 patients who underwent CRRT were included, and the in-hospital mortality rate was 67.3% during the follow-up period. The 7-day, 30-day, and in-hospital mortality rates increased toward higher CAR quartiles (all p < 0.001). After adjusting for confounding variables, the higher quartile groups had an increased risk of in-hospital mortality (quartile 3: adjusted hazard ratio [aHR], 1.26, 95% confidence interval [CI], 1.10-1.43, p < 0.001; quartile 4: aHR, 1.22, 95% CI, 1.07-1.40, p = 0.003). CAR combined with Acute Physiology and Chronic Health Evaluation II or Sequential Organ Failure Assessment scores significantly increased the predictive power compared to each severity score alone for AUC, NRI, and IDI (all p < 0.05).

Conclusions: A high CAR is associated with increased in-hospital mortality in critically ill patients requiring CRRT. The combined use of CAR and severity scores provides better predictive performance for mortality than the severity score alone.

Introduction: The regional variation in the use of percutaneous kidney biopsy in Japan remains unknown. There are several large datasets of kidney biopsies in Japan, but an exhaustive survey of kidney biopsies is lacking.

Methods: We analyzed insurance claims for percutaneous kidney biopsies registered in the National Database of Health Insurance Claims and Specific Health Checkups of Japan, which is the closest to a complete dataset of kidney biopsies performed in Japan. In combination with other nationwide survey results, the number of inpatient percutaneous kidney biopsies per population in each prefecture was calculated. Factors associated with the frequency of percutaneous kidney biopsies were also explored.

Results: The database contained 22,419 health insurance claims for percutaneous kidney biopsy in the fiscal year 2020. The frequency of inpatient percutaneous kidney biopsies could be up to 4.8 times as frequent in one prefecture than in another, even after adjusting for age and sex. The frequency of inpatient percutaneous kidney biopsies showed a positive correlation with the number of annual kidney transplants and patients on peritoneal dialysis per population and a weak negative correlation with the prevalence of reduced kidney function in the population aged 40-74 years.

Conclusion: We found a large regional variation in the frequency of inpatient percutaneous kidney biopsies. Kidney transplants and peritoneal dialysis might be offered more frequently in regions with a higher frequency of kidney biopsy. This is the first dataset that shows more than 20,000 kidney biopsies were performed per year in Japan, as of 2020.

Background: Chronic kidney disease (CKD) is an increasingly prevalent disease that affects approximately 10-12% of the global population. Therefore, it is considered a public health priority. Persistent and systemic low-grade chronic inflammation (CI) is an important part of the poor prognosis in CKD, especially for patients with advanced disease. For example, CI worsens anemia and promotes atherosclerosis. Therefore, CI deserves our attention.

Summary: The formation of CI in CKD involves many aspects. Among them, the decline in the glomerular filtration rate leads to the influence of substances or inflammatory cytokines that should be cleared in time. In addition, oxidative stress, the gut, and the gut microbiota are also influencing factors.

Key messages: In this review, we highlight the mechanisms involved in the development of CI in CKD.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited disease of the kidney. It occurs in adulthood but is also rarely diagnosed in early childhood. The majority of the disease-causing variants observed in ADPKD patients are in two genes: PKD1 and PKD2.

Methods: 237 patients from 198 families with a clinical diagnosis of ADPKD were screened for PKD1 and PKD2 genetic variants using Sanger sequencing and multiple ligation-dependent probe amplification analysis.

Results: Disease-causing (diagnostic) variants were identified in 173 families (211 patients), 156 on PKD1 and 17 on PKD2. Variants of unknown significance were detected in 6 additional families, while no mutations were found in the remaining 19 families. Among the diagnostic variants detected, 51 were novel. In ten families, seven large rearrangements were found and the molecular breakpoints of 3 rearrangements were identified. Renal survival was significantly worse for PKD1-mutated patients, particularly those carrying truncating mutations. In patients with PKD1 truncating (PKD1-T) mutations, disease onset was significantly earlier than in patients with PKD1 non-truncating variants or PKD2-mutated patients.

Conclusions: Comprehensive genetic testing confirms its utility in diagnosing patients with ADPKD and contributes to explaining the clinical heterogeneity observed in this disease. Moreover, the genotype-phenotype correlation can allow for a more accurate disease prognosis.

Introduction: The aims of this study were to evaluate the frequency and causes of hospitalizations in the posttransplant period of children, investigate the risk factors, and evaluate the relationship between hospitalizations and renal prognosis in the long term.

Methods: We retrospectively reviewed the files of pediatric renal transplant patients, followed at least 6 months after kidney transplantation, in our center. Clinical information including age at transplantation, gender, primary disease, donor type, immuno-suppressive medication, hospitalization dates, and indications (infections and non-infectious) during follow-up period and graft outcomes was recorded.

Results: A total of 74 children (46 males) were followed up for a median of 54 months. Among them, 69 patients (93.2%) were hospitalized 446 times. The most common cause of hospitalizations was infections (314 times, 70%). Urinary tract infections were the most important cause followed by upper respiratory tract infections. Forty (54%) patients were hospitalized 132 times (29.5%) for non-infectious reasons. The most common non-infectious reason was nonspecific graft dysfunction (19 patients, 30 times), followed by rejection (17 patients, 27 times). Younger age, use of induction therapy, and having congenital anomalies of kidney and urinary tract (CAKUT) were found to be risk factors for increased hospitalization rates (p < 0.05). The number of hospitalizations was found to be negatively affecting the final glomerular filtration rate of transplant recipients (p: 0.04, r: -0.023).

Conclusion: Patients with CAKUT, who received induction therapy, and small children were hospitalized more frequently after transplantation. Strategies to prevent hospitalizations will achieve a better graft prognosis.

Introduction: MicroRNAs (miRNAs), short noncoding RNAs, are involved in the modulation of gene expression, mainly by inhibiting the translation of mRNAs. Under physiological conditions, miRNAs are involved in viral infections and immune responses, among others; aberrant miRNA expression has been associated with kidney transplant pathologies, but a comprehensive comparison of later, particularly in tissue sections, is still pending.

Methods: We used the genome-wide screening of miRNAs to identify those potentially involved in the disease processes after kidney transplantation. RNA was isolated from formalin-fixed paraffin-embedded kidney biopsy samples. Study included 8 patients with acute tubular necrosis (ATN), 8 patients with antibody-mediated rejection (ABMR), 10 patients with T-cell-mediated rejection (TCMR), 10 patients with BK polyomavirus-associated nephropathy (BKPyVAN), and 12 surveillance biopsies from patients with stable allograft function and no major abnormalities (normal allografts, CTRL).

Results: We found 136 miRNAs differentially expressed in diseased kidney transplant tissue compared with normal allografts; of these, 74 miRNAs were differentially expressed in ABMR, 65 in ATN, 62 in BKPyVAN, 69 in TCMR, and 16 miRNAs were not associated with a specific disease phenotype. In addition, 29 miRNAs were differently expressed between ABMR and ATN, 39 between BKPyVAN and TCMR, and 20 between BKPyVAN and ABMR, and 38 between ABMR and TCMR.

Conclusion: Our findings show that miRNA derived from kidney allograft biopsy samples represent an additional diagnostic tool to distinguish different disease phenotypes. This finding has the potential to assist clinicians in therapeutic decision-making and to translate to noninvasive monitoring of patients, e.g., blood samples.

The clinical features of cerebellar vermis hypoplasia, oligophrenia, ataxia, coloboma, and hepatic fibrosis (COACH) characterize the rare autosomal recessive multisystem disorder called COACH syndrome. COACH syndrome belongs to the spectrum of Joubert syndrome and related disorders (JSRDs) and liver involvement distinguishes COACH syndrome from the rest of the JSRD spectrum. Developmental delay and oculomotor apraxia occur early but with time, these can improve and may not be readily apparent or no longer need active medical management. Congenital hepatic fibrosis and renal disease, on the other hand, may develop late, and the temporal incongruity in organ system involvement may delay the recognition of COACH syndrome. We present a case of a young adult presenting late to a Renal Genetics Clinic for evaluation of renal cystic disease with congenital hepatic fibrosis, clinically suspected to have autosomal recessive polycystic kidney disease. Following genetic testing, a reevaluation of his medical records from infancy, together with reverse phenotyping and genetic phasing, led to a diagnosis of COACH syndrome.

Introduction: Inflammation is associated with development of chronic kidney disease (CKD). However, the association of the high-sensitivity C-reactive protein (hs-CRP)/albumin ratio (CAR) on the risk of CKD in the general population is unknown. This study explored the relationship between the CAR and CKD and the ability of this ratio to predict CKD in the general population.

Methods: A total of 47,472 participants in the Kailuan study who met the inclusion criteria in 2010 were selected and grouped using the quartile method. A Cox proportional hazard regression model was used to evaluate the association of the CAR on the risk of CKD. The C-index, net reclassification index (NRI), and overall identification index (IDI) were calculated to evaluate the ability of the CAR to predict CKD.

Results: During a follow-up of 378,383 person-years, CKD events occurred in 6,249 study participants (13.16%). The Cox proportional hazard regression model showed that the hazard ratio (95% confidence interval) for CKD events was 1.18 (1.10-1.28) in the Q3 group and 1.42 (1.32-1.53) in the Q4 group when compared with the Q1 group. Compared with the single index, the C-index, NRI, and IDI values were significantly improved when the CAR was added for prediction of risk of CKD.

Conclusions: A higher CAR was an independent risk factor for CKD. The ability of the CAR to predict CKD was better than that of hs-CRP or albumin. The CAR provides an important reference index for predicting the risk of CKD.