Pediatric Nephrology最新文献

Background: Serum and urinary uromodulin are emerging as potential cardiovascular risk factors. The aim of our study was to determine uromodulin in both serum and urine to evaluate their potential as early cardiovascular risk markers and markers of kidney function in children and young adults.

Methods: This case-control study included 72 participants - 42 children and young adults with chronic kidney disease stages 1-2 and 30 healthy controls. Serum and urinary uromodulin concentrations were determined along with anthropometric measurements, body composition, and standard laboratory measurements in cardiovascular and kidney health assessment.

Results: Urinary uromodulin-to-creatinine was significantly decreased in the group with chronic kidney disease (p < 0.001). It also correlated significantly with anthropometric measurements, systolic pressure, creatinine (but not with glomerular filtration rate), urate, and homocysteine. Serum uromodulin did not differ from healthy control subjects. Serum uromodulin correlated significantly with albuminuria, showing its minor potential in kidney health assessment in the young.

Conclusions: Urinary uromodulin is a better predictor of kidney and cardiovascular early damage than serum uromodulin in children and young adults with only mild chronic kidney disease. In at-risk individuals, lower urinary uromodulin levels might reflect a reduced functional kidney and cardiovascular reserve. Further research in the pediatric population is warranted.

Background: Severe respiratory complications following kidney transplantation have been reported, yet remain poorly understood in the pediatric population. This study aimed to document respiratory disease in this population.

Methods: At annual follow-ups, patients completed a respiratory symptoms questionnaire and underwent pulmonary function tests (PFTs). We defined respiratory disease in children when they had clinical disorders and/or PFT abnormalities.

Results: Among 236 children included, 110 (41%) exhibited respiratory involvement: 59 (53%) had only clinical disorders, 38 (35%) had only PFT abnormalities, and 13 (12%) had both. Of those with PFT abnormalities, 15 (7%) had obstructive impairment, 12 (6%) had restrictive impairment, and 30 (24%) showed decreased lung diffusion capacity for carbon monoxide (DLCO)/transfer coefficient for carbon monoxide (KCO). In the multivariate analysis, being over 3.5 years of age at the time of transplantation was associated with a reduced risk of respiratory involvement (OR 0.30, CI [0.14; 0.63], p = 0.002), such as induction with basiliximab (OR 0.39, CI [0.17; 0.90], p = 0.03). Conversely, history of immune deficiency, male gender, positive PCR for BK virus and diastolic hypertension were associated with an increased risk (OR 5.96, CI [2.15; 16.51], p = 0.0006, OR 1.97, CI [1.03; 3.77], p = 0.04, OR 3.77, CI [1.14; 12.52], p = 0.03 and OR 2.21, CI [1.13; 4.32], p = 0.02, respectively). Bronchial lesions, such as bronchiectasis, were predominantly observed on tomography.

Conclusions: Given the risk of irreversible lung damage, we recommend systematic clinical and functional respiratory monitoring in case of respiratory symptoms, recurrent lower respiratory tract infections, and risk factors in their follow-up.

The coronavirus disease 2019 (COVID-19) pandemic, instigated by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has profoundly impacted healthcare infrastructures around the globe. While children are usually asymptomatic or have mild symptoms, children with pre-existing kidney conditions require specialized attention. This pivotal report, championed by the International Pediatric Nephrology Association (IPNA), delivers precise and actionable recommendations tailored for pediatric patients with kidney ailments in this pandemic landscape. Central to our findings are rigorous infection control protocols. These are particularly stringent in high-risk zones, emphasizing telehealth's indispensable role, the significance of curtailing in-person consultations, and the imperative of following rigorous guidelines in regions with heightened COVID-19 prevalence. Additionally, the report delves into vaccination approaches for children with kidney issues, highlighting that the choice of vaccine is often governed by regional accessibility and policy frameworks, rather than a universal preference. A notable observation is the potential correlation between COVID-19 vaccines and specific kidney disorders. However, establishing a direct causal link remains elusive. In summary, our research accentuates the critical need for specialized pediatric kidney care during global health crises and reaffirms the continuous research imperative, especially regarding vaccination ramifications.

Background: Podocyte depletion is a critical factor in glomerulosclerosis development. While podocyte numbers per glomerulus typically decline with age in adults, they are hypothesized to increase during childhood. However, studies on podocyte number progression in childhood have been limited.

Methods: This retrospective analysis examined forensic autopsy cases of Japanese children without kidney disease, aged under 192 months, between April 2010 and March 2023. Podocytes were identified using immunostaining with an anti-transducin-like enhancer of split 4 antibody and p57. Podometric parameters were estimated using the correction factor method, allowing estimation from a single histologic section.

Results: This study included 68 cases with a median age of 9 months (interquartile range [IQR], 4-78). All podometric parameters correlated with age. Children younger than 36 months displayed significantly fewer podocyte numbers per glomerulus (median, 517; IQR, 483-546) compared to those aged 36 months and older (median, 616; IQR, 595-649; p < 0.001). Regression analysis revealed a significant age-related increase in podocyte numbers per glomerulus in children under 36 months (slope, 3.76; p < 0.001; 95% confidence interval [CI], 2.34-5.19), but not in those aged 36 months and older (slope, 0.25; p = 0.16; 95% CI, - 0.10-0.61). Additionally, the change in the slope at 36 months was significant (p < 0.001; 95% CI, 1.02-2.49); however, this increase did not appear linked to podocyte division.

Conclusions: Podocyte numbers per glomerulus increased from birth until 36 months and then stabilized. These findings could facilitate the development of novel treatments for chronic kidney disease caused by glomerulosclerosis and contribute to pediatric kidney health research.

Background: The gut-kidney axis is implicated in chronic kidney disease (CKD) morbidity. We describe how a panel of gut microbiome-derived toxins relates to kidney function and neurocognitive outcomes in children with CKD, consisting of indoleacetate, 3-indoxylsulfate, p-cresol glucuronide, p-cresol sulfate, and phenylacetylglutamine.

Methods: The Chronic Kidney Disease in Children (CKiD) cohort is a North American multicenter prospective cohort that enrolled children aged 6 months to 16 years with estimated glomerular filtration rate (eGFR) 30-89 ml/min/1.73 m². Data from the 2-year study visit were used for this analysis. Toxin quantification (Metabolon Inc., Durham, NC) was performed with ultra-high performance liquid chromatography/tandem mass spectrometry. Executive function and echocardiograms were assessed. Regression analysis examined the association of toxin levels with eGFR, CKD etiology, and neurocognitive and cardiac assessments (adjusted for age, sex, and urine protein:creatinine [UPCR]).

Results: There were 150 CKiD participants included in this study. All toxins levels were significantly inversely correlated with eGFR (Spearman's rho - 0.45 to - 0.69). Children with non-glomerular CKD had significantly higher levels of 3-indoxylsulfate, phenylacetylglutamine, and p-cresol glucuronide. The toxin levels did not associate with neurocognitive outcomes. P-cresol glucuronide and phenylacetylglutamine negatively associated with left ventricular mass index z score, but did not associate with left ventricular hypertrophy.

Conclusions: Children with CKD have high levels of circulating gut microbiome-derived toxins. The levels of these toxins are strongly correlated with eGFR. There appear to be differences in toxin level based on glomerular versus non-glomerular etiology, even when accounting for the differences in eGFR between these two subgroups. In this sample, we did not detect any associations between these toxin levels and neurocognitive or cardiac outcomes.

The conventional methods for assessing kidney function, such as glomerular filtration rate and microalbuminuria, provide only partial insight into kidney function. Multi-parametric and multi-nuclear functional resonance magnetic imaging (MRI) techniques are innovative approaches to unraveling kidney physiology. Multi-parametric MRI includes various sequences to evaluate kidney perfusion, tissue oxygenation, and microstructure characterization, including fibrosis-a key pathological event in acute and chronic kidney disease and in transplant patients-without the need for invasive kidney biopsy. Multi-nuclear MRI detects nuclei other than protons. ²³Na MRI enables visualization of the corticomedullary gradient and assessment of tissue sodium storage, which can be particularly relevant for personalized medicine in salt-wasting tubular disorders. Meanwhile, ³¹P-MRS measures intracellular phosphate and ATP variations, providing insights into oxidative metabolism in the muscle during exercise and recovery. This technique can be useful for detecting subclinical ischemia in chronic kidney disease and in tubulopathies with kidney phosphate wasting. These techniques are non-invasive and do not involve radiation exposure, making them especially suitable for longitudinal and serial assessments. They enable in vivo evaluation of kidney function on a whole-organ basis within a short acquisition time and with the ability to distinguish between medullary and cortical compartments. Therefore, they offer considerable potential for pediatric patients. In this review, we provide a brief overview of the main imaging techniques, summarize available literature data on both adult and pediatric populations, and examine the perspectives and challenges associated with multi-parametric and multi-nuclear MRI.

Chyloperitoneum is an uncommon diagnosis in peritoneal dialysis (PD) patients. While admitted for emesis and feeding intolerance, a 16-month-old male on PD developed milky-colored dialysate with increased triglycerides, indicating chyloperitoneum. In adult PD patients, chyloperitoneum can indicate potentially life-threatening pathologies including malignancies and liver or heart disease. By contrast, pediatric patients on PD with chyloperitoneum had recently undergone PD catheter or gastrostomy tube placement with presumed disruption of abdominal lymphatics. Slowing lymph flow through dietary manipulation and rarely, temporary withholding of PD, resolved chyloperitoneum. We report a toddler on PD with chyloperitoneum in whom abdominal investigation showed multifocal hepatoblastoma. Chemotherapy and a medium chain triglycerides (MCTs)-based diet led to prompt resolution of chyloperitoneum. Intrabdominal malignancy in this patient illustrates the importance of a prompt, thorough evaluation of chyloperitoneum to allow definitive therapy if required.

Background: This study aimed to evaluate the incidence, contributing factors, and clinical outcomes of acquired cystic kidney disease (ACKD) in children undergoing kidney replacement therapy (KRT).

Methods: We conducted a cross-sectional, territory-wide study at the designated pediatric nephrology center in Hong Kong. ACKD was defined as the presence of ≥ 3 cysts in the native kidneys, excluding congenital or hereditary cystic diseases. Between June to December 2023, all paediatric patients receiving KRT in Hong Kong underwent ultrasonography, non-contrast magnetic resonance imaging (MRI), or both. Contrast-enhanced computed tomography was performed for patients with complex cysts.

Results: Forty-three children (56% female; median age 14.7 years; IQR, 11.7-18.7) were included in the analysis. ACKD was detected in 18 children (42%). Nine subjects had complex cysts (grade 2, n = 5; grade 2F, n = 2; grade 3, n = 2). Most patients with ACKD (89%) were asymptomatic. One patient (5.5%) developed back pain and gross haematuria 72 months after initiation of KRT. Another patient (5.5%) developed infected cyst with back pain and clinical sepsis 60 months following KRT initiation. A dialysis duration of ≥ 28 months was the only significant factor associated with ACKD development (77.8% vs. 40%; p = 0.028; OR_adj 6.09, 95% CI 1.43-25.82, p = 0.014). The diagnostic yield of paired ultrasound and MRI was superior to ultrasound alone.

Conclusions: ACKD is prevalent among children and adolescents with kidney failure, with most cases being asymptomatic, however serious complications may arise. Longer duration of dialysis is significantly associated with ACKD development. Therefore, early transplantation and active ACKD surveillance are crucial for children receiving KRT.