Nephron最新文献

We describe the unique case of a patient in whom two ciliopathies with autosomal recessive transmission were clinically and molecularly diagnosed: nephronophthisis type 1 (NPHP1) and Alström syndrome (AS). NPHP1 is one of the main genetic causes of terminal kidney failure in childhood. AS is an ultra-rare multi-systemic disease, characterized by progressive kidney disease, hepatic failure, dystrophy of the rods and cones to blindness, slowly progressive neuro-sensory deafness, dilated cardiomyopathy, obesity, insulin resistance/type 2 diabetes mellitus. The coexistence in the same patient of two rare syndromes with overlapping clinical manifestations but genetically different is an eventuality to be considered. This case report would describe the onset and progression of the multi-organ manifestations of both syndromes to highlight that ciliopathies present a strong phenotype overlap but also specific peculiarities. Therefore, to make a correct diagnosis that is essential to achieve the best clinical management could be challenging.

Introduction: Autosomal recessive polycystic kidney disease (ARPKD) is associated with pathogenic variants in the PKHD1 gene. Autosomal dominant polycystic kidney disease (ADPKD) is mainly associated with pathogenic variants in PKD1 or PKD2. The present study aimed to identify the clinical and genetic features of Turkish pediatric ARPKD and ADPKD patients.

Methods: This multicenter, retrospective cohort study included 21 genetically confirmed ARPKD and 48 genetically confirmed ADPKD patients from 7 pediatric nephrology centers. Demographic features, clinical, and laboratory findings at presentation and during 12-month intervals were recorded.

Results: The median age of the ARPKD patients at diagnosis was lower than the median age of ADPKD patients (10.5 months [range: 0-15 years] vs. 5.2 years [range: 0.1-16 years], respectively, [p = 0.014]). At the time of diagnosis, the median eGFR in the ARPKD patients was lower compared to that of ADPKD patients (81.6 [IQR: 28.7-110.5] mL/min/1.73 m2 and 118 [IQR: 91.2-139.8] mL/min/1.73 m2, respectively, [p = 0.0001]). In total, 11 (52.4%) ARPKD patients had malnutrition; 7 (33.3%) patients had growth retardation at presentation; and 4 (19%) patients had both malnutrition and growth retardation. At diagnosis, 8 (16.7%) of the ADPKD patients had malnutrition, and 5 (10.4%) patients had growth retardation. The malnutrition, growth retardation, and hypertension rates at diagnosis were higher in the ARPKD patients than the ADPKD patients (p = 0.002, p = 0.02, and p = 0.0001, respectively). ARPKD patients with malnutrition and growth retardation had worse renal survival compared to the patients without (p = 0.03 and p = 0.01). Similarly, ADPKD patients with malnutrition had worse renal survival compared to the patients without (p = 0.002). ARPKD patients with truncating variants had poorer 3- and 6-year renal outcome than those carrying non-truncating variants (p = 0.017).

Conclusion: Based on renal survival analysis, type of genetic variant, growth retardation, and/or malnutrition at presentation were observed to be factors associated with progression to chronic kidney disease (CKD). Differentiation of ARPKD and ADPKD, and identification of the predictors of the development of CKD are vital for optimal management of patients with ARPKD or ADPKD.

Introduction: Presence of subclinical intestinal inflammation has repeatedly been shown in IgA nephropathy (IgAN) and the degree of histological inflammation has correlated with abnormal urinary findings. There is lack of noninvasive biomarkers evaluating the presence of subclinical intestinal damage in IgAN. We conducted this study hypothesizing that selected biomarkers regarded as indirect markers of intestinal damage could be elevated in IgAN.

Methods: Eighty-five primary IgAN patients (median age 55 years, 54% men) participated in this single-center study in Tampere, Finland. None had end-stage kidney disease or previously diagnosed enteropathies. Celiac disease was excluded with serum transglutaminase 2 antibody (TG2Ab) and endomysial antibody tests and inflammatory bowel disease with fecal calprotectin. Intestinal damage was evaluated from sera with analyses of intestinal fatty-acid binding protein (I-FABP), soluble cluster of differentiation molecule 14 (sCD14), and lipopolysaccharide binding protein. Fourteen people suffering from dyspepsia and 15 healthy people served as controls.

Results: I-FABP levels among IgAN patients were higher than in the healthy controls (median 830 pg/mL vs. 289 pg/mL, p < 0.001). Also, sCD14 was increased in IgAN patients compared to dyspepsia controls. Although TG2Ab levels were within the normal range among IgAN patients, they were higher than in the healthy controls (median 1.3 U/mL vs. 0.6 U/mL, p < 0.001).

Conclusions: Elevated serum levels of I-FABP were present in primary IgAN patients without known enteropathies. Serum I-FABP may indicate the presence of subclinical intestinal damage. These findings encourage further investigation into the role of the intestine in the pathophysiology of IgAN.

Introduction: Psychological disorders are strong predictors of life expectancy and have an impact on quality of life. Autosomal dominant polycystic kidney disease (ADPKD) is frequently diagnosed before the onset of subjective symptoms. Similar to other disorders of genetic origin, ADPKD may be a source of remarkable psychological discomfort. One way of coping with emotional distress is its suppression, and this could be measured. Our study aimed to provide data on the acceptance of illness, the emotional suppression of anger, and both anxiety and depression as well as satisfaction with life in young patient population of early-stage ADPKD in comparison to healthy demographically matched individuals.

Methods: Fifty patients in the asymptomatic stage of ADPKD with an eGFR >60 mL/min (4p MDRD) and 50 healthy demographically matched individuals were included in this study. Participants filled out a set of psychological questionnaires: Acceptance of Illness Scale (AIS), Courtauld Emotional Control Scale (CECS), and Satisfaction with Life Scale (SWLS).

Results: Asymptomatic patients with ADPKD had 80% scores indicative of disease acceptance in AIS. As compared to healthy individuals, they presented with significantly stronger suppression of both anxiety and depression but not anger. The ADPKD group had significantly lower satisfaction with life in comparison to the healthy group.

Conclusion: Asymptomatic ADPKD patients had a high level of disease acceptance. Anger suppression in this group was comparable to healthy individuals, but anxiety and depression were controlled more intensively. Despite the asymptomatic course of the disease, ADPKD patients revealed lower satisfaction with life in comparison to healthy persons.

Heart disease is one of the leading causes of death in autosomal dominant polycystic kidney disease (ADPKD) patients. Left ventricular hypertrophy (LVH) is an early and severe complication in ADPKD patients. Two decades ago, the prevalence of LVH on echocardiography in hypertensive ADPKD patients was shown to be as high as 46%. Recent studies using cardiac magnetic resonance imaging have shown that the prevalence of LVH in ADPKD patients may be lower. The true prevalence of LVH in ADPKD patients is controversial. There is evidence that factors other than hypertension contribute to LVH in ADPKD patients. Studies have shown that young normotensive ADPKD adults and children have a higher left ventricular mass index compared to controls and that the prevalence of LVH is high in patients with ADPKD whose blood pressure is well controlled. Polycystin-1 (PC-1) and polycystin-2 (PC-2) control intracellular signaling pathways that can influence cardiac function. Perturbations of PC-1 or PC-2 in the heart can lead to profound changes in cardiac structure and function independently of kidney function or blood pressure. PC-1 can influence mammalian target of rapamycin and mitophagy and PC-2 can influence autophagy, processes that play a role in LVH. Polymorphisms in the angiotensin-converting enzyme gene may play a role in LVH in ADPKD. This review will detail the pathophysiology of LVH, beyond hypertension, in ADPKD.

Introduction: Acute kidney injury (AKI) is a common clinical disease, especially in the intensive care unit. Identification of reliable biomarker is of great clinical significance and benefit the therapy and prevention of AKI. The clinical significance and function of miR-874-3p in AKI development were evaluated in this study aiming to explore a novel biomarker for AKI.

Methods: There were 83 AKI patients and 56 healthy individuals included, and the serum samples were collected. The AKI animal models were established via ischemic/reperfusion (I/R) and LPS on C57BL/6 mice. The expression of miR-874-3p was evaluated using PCR, while the potential downstream targets were also validated in AKI mice. The regulatory mechanism of miR-874-3p was investigated in AKI cell model established with HK-2 cell by I/R.

Results: miR-874-3p was downregulated in both AKI patients and established AKI mice models. The downregulation of miR-874-3p could discriminate against AKI patients and predict poor prognosis of patients. miR-874-3p was negatively correlated with the levels of serum creatine, blood urea nitrogen, CRP, NEU, and PCT and positively correlated with the eGFR of AKI patients. In I/R- and LPS-induced AKI mice, overexpressing miR-874-3p could alleviate renal dysfunction, oxidative stress, and inflammation induced by AKI. Additionally, miR-874-3p could negatively regulate the expression of MSRB3, which was speculated as the potential mechanism underlying the function of miR-874-3p in AKI. Overexpression of miR-874-3p could alleviate the I/R-induced HK-2 cell apoptosis and decreased proliferation, which was reversed by the upregulation of MSRB3.

Conclusion: miR-874-3p served as a diagnostic and prognostic biomarker of AKI and mediate the severity and development of AKI via targeting MSRB3.

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.

As nephrology practice is evolving toward precision medicine, and genetic tests are becoming widely available, basic genetic literacy is increasingly required for clinical nephrologists. Yet, decisions based on results of genetic tests are seldom straightforward. We report a 37-year-old woman with autosomal dominant polycystic kidney disease (ADPKD) who was referred for medically assisted reproduction with monogenic preimplantation genetic testing (PGT-M). The PKD1 and PKD2 genes were screened for pathogenic variants. Sequencing analysis revealed the presence of three novel missense single nucleotide variants, two in the PKD1 gene - c.349T>G, p.(Leu117Val) and c.1736C>T, p.(Pro579Leu); and the third in the PKD2 gene - c.1124A>G, p.(Asn375Ser). Bioinformatic predictions of the functional effects of those three missense variants were inconsistent across different software tools. The family segregation analysis, which was mandatory to identify the relevant variant(s) for PGT-M, strongly supported that the disease-causing variant was PKD1 c.349T>G p.(Leu117Val), while the other two were nonpathogenic or, at most, phenotypic modulators. Proving the pathogenicity of novel variants is often complex but is critical to guide genetic counseling and screening, particularly when discussing reproductive alternatives for primary prevention in the progeny of at-risk couples. The family reported herein illustrates those challenges in the setting of ADPKD, and the invaluable importance of a detailed family history and segregation analysis for proper clinical annotation of novel variants. Basic genetic knowledge and proper clinical annotation of novel allelic variants in genes associated with hereditary kidney disorders are increasingly necessary for the contemporary practice of clinical nephrology.

Background: Chronic kidney disease (CKD) affects 11-13% of the world population. The main risk factors for CKD include diabetes, hypertension, and obesity. Metabolic syndrome (MS) is associated with the onset of CKD in the nondiabetic population. Obesity and MS are also risk factors for a worse progression of established CKD. Therapeutic exercise is an effective option to treat and manage obesity, MS, and diabetes in the general population. However, the evidence on the effect of exercise on patients with CKD, obesity, and MS is scarce.

Summary: We evaluated available evidence on the effect of therapeutic exercise in patients with CKD, excluding dialysis, particularly in improving the metabolic risk factors and main renal outcomes: renal function loss and albuminuria/proteinuria. This review includes prospective studies and clinical trials. A total of 44 studies were analysed in 1,700 subjects with renal disease (2-5), including patients with renal transplantation. Most studies did not prove a major effect of exercise on albuminuria/proteinuria, glomerular filtration rate (GFR), obesity, or MS. These results are intriguing and deserve attention. The exploratory nature of most studies, including a low number of cases and short follow-up, might explain the lack of efficacy of exercise in our analysis. Specific aspects like the type of exercise, frequency, intensity, duration, accommodation during follow-up, individualization, safety, and adherence are crucial to the success of therapeutic exercise. The beneficial role of exercise in patients with CKD remains to be determined.

Key messages: Key messages of this review are as follows. (1) The effect of therapeutic exercise on renal and metabolic outcomes in patients with CKD remains to be determined. (2) According to the evidence selected, therapeutic exercise seems to be safe to treat patients with CKD. (3) Most studies are exploratory by nature, with results that need further investigation. (4) Therapeutic exercise is a complex procedure that must be specifically designed to treat patients with CKD.