Renal Cysts Research Articles

P-15 DIAGNOSTIC PITFALL - A RARE CASE OF HYPERCALCEMIA

Abstract Introduction Infantile hypercalcaemia type 1 (IIH) is an autosomal recessive disorder characterized by homozygous mutations in the CYP24A1 gene that encodes the 24-hydroxylase enzyme used to inactivate 1,25-(OH)2-vitamin D. Clinical Case A 24-year-old male was referred to our department for the evaluation of hypertension and nephrolithiasis, in the context of hypercalcemia. The general physical examination and the endocrinological assessment revealed no abnormalities. The patient was initially evaluated in nephrology & urology departments, where computed tomography (CT) revealed renal nephrocalcinosis and a lower right renal cyst, with no findings at thoracic level. Laboratory results confirmed hypercalcemia (total calcium 12.6 mg/dL, Ca++ at 5.49 mg/dL), alongside low parathyroid hormone (PTH) at 3 pg/mL. Malignancy was ruled out by normal PTH-related peptide levels (<0.5 pmol/L) and normal 25-hydroxyvitamin D levels (46 ng/mL), though 1,25-dihydroxyvitamin D was slightly elevated (81.8 pg/mL; Ref: 19.9−79.3 pg/mL). Bone metabolism markers, including FGF-23, serum crosslaps, and osteocalcin, were normal, excluding metabolic bone disease. Urine/24h: low urinary calcium (0.27 g/24h) and normal urinary phosphate (0.87 g/24h). In the diagnostic algorithm, hypercalcemia can be PTH-mediated, non-PTH-mediated, medication-induced, and miscellaneous causes. The patient's low PTH and suppressed PTH-rp excluded primary hyperparathyroidism and malignancy-related hypercalcemia. Normal 25(OH) vitamin D and slightly elevated 1,25(OH) vitamin D levels raised the suspicion of extrarenal 1-alpha-hydroxylation of vitamin D, a mechanism seen in granulomatous diseases such as sarcoidosis or tuberculosis, or in lymphomas. However, granulomatous diseases were excluded based on negative chest X-ray and thoracic CT findings and normal angiotensin-converting enzyme (ACE) levels. Other possible malignancies were excluded: germ cell tumors, such as non-seminomatous germ cell tumors, testicular cancers, particularly seminomas or choriocarcinomas, Hodgkin's lymphoma and multiple myeloma. Additionally, through medical history, clinical examination, and laboratory tests, we have also excluded hyperthyroidism, acromegaly, pheochromocytoma, adrenal insufficiency, bed rest/immobilization, parenteral nutrition, and supplements. Consequently, a genetic cause of abnormal renal calcium metabolism was suspected. Genetic testing revealed a heterozygous pathogenic mutation in the CYP24A1 gene, which is linked to Infantile Hypercalcemia Type 1. The patient's diagnosis of IIH was confirmed by the detection of the CYP24A1 mutation. Management of his condition focuses on controlling calcium levels through dietary intake and diuresis to prevent kidney stones, as there is no specific treatment available. Conclusion This case report highlights the importance of determining the etiology of hypercalcemia and the significance of genetic testing in clinical management.

Varied terminology by radiologists to describe Bosniak class III and IV cystic renal masses.

The Bosniak classification is designed to standardize evaluation of cystic renal masses and to communicate the risk of malignancy. To determine whether radiologists vary in their communication of Bosniak class III and IV cystic renal masses. This retrospective study included 186 patients with CT or MRI reporting a Bosniak class III or IV mass. Radiology reports were evaluated to determine the noun representing the mass, the modifier to convey the likelihood of cancer, and recommendations for urologic referral. Electronic medical records were reviewed to determine if the patient saw a urologist. Of the patients, 112 (60%) had a class III mass and 74 (40%) had a class IV mass. Class III masses were more likely to be represented by the noun "lesion" rather than a "mass" (61/112 [54%] vs. 31/112 [28%]). Class IV masses are more likely to be represented as a "mass" (36/74 [59%] vs. 28/74 [38%]; P < 0.015). Cancer was described in 100/186 (54%) cases: 38/112 (35%) class III masses and 62/74 (72%) class IV masses (P < 0.001). The cancer terminology used included "renal cell carcinoma" (n = 57), "neoplasm" (n = 12), and "malignancy/malignant" (n = 86). Most radiology reports (n = 133, 72%) did not recommend urologic referral but 183 (98%) patients were referred and 181 (97%) ultimately saw a urologist. Radiologists vary in their communication of class III and IV masses, reflecting historical terminology usage, nuanced interpretations, and an evolving understanding of renal cell carcinoma biology. This variance had minimal impact on urologic referral rates.

Trends in pulmonary function in patients with Birt-Hogg-Dubé syndrome: a retrospective cohort study

ABSTRACT Background Birt-Hogg-Dubé syndrome (BHD), a rare genetic disease characterized by multiple pulmonary cysts, can lead to spontaneous pneumothorax, cutaneous hamartomas, renal cysts, and renal cell cancer. The overall aim of this study was to assess clinical characteristics of patients with BHD-emphasizing on trends in pulmonary function patterns. Methods By use of data from electronic patient journals, we conducted a retrospective cohort study on clinical characteristics and pulmonary function tests (PFT) from patients with BHD, who were clinically followed-up in a Danish tertiary referral center for rare and interstitial lung diseases. Results A total of 101 patients (44 men (43.6%); mean age 48.4 years (SD ± 15.9 years)) with BHD were included. Chest HRCT scans revealed pulmonary cysts in 82.2% of whom 38.6% had experienced at least one pneumothorax (median 2; IQR1–4). Baseline PFT showed FEV1/FVC ratio and RV% within normal values of predicted. In 28.7% of the patients, a slight decrease in DLco below 80% of predicted was observed (mean 86.9% ± SD 15.8%). At two years follow-up, there were no significant declines in FEV1 and FVC, nor after accounting for age, gender, and smoking. At baseline cutaneous manifestations were found in 58.4% of the patients, 47.5% had benign renal cysts, and 11.9% had renal tumours. Conclusion More than 80% of patients with BHD presented with pulmonary cysts, but consistent with other studies all had normal PFTs at two years follow-up. We conclude that routine monitoring of pulmonary function and pulmonary follow-up may not be necessary in patients with BHD.

Tuberous sclerosis complex-associated kidney disease in children.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder which can have manifestations in the kidneys, along with other organ systems. Children with TSC may develop kidney lesions at any point during childhood, and typically these are angiomyolipomata (AML) and/or kidney cysts. Children may also have hypertension associated with TSC-associated kidney disease, and rarely reduced kidney function. New guidelines for the management of TSC-associated kidney disease in children and adults were published in 2024. This educational review summarises the relevant clinical aspects of these guidelines for paediatric nephrologists through a series of four clinical cases. These cases cover management of hypertension, frequency of follow-up and frequency of kidney imaging. Difficult clinical scenarios are reviewed, such as the management of TSC2-PKD1 contiguous gene syndrome and the management of large AMLs in children with TSC.

The Diagnostic Yield of Genomic Sequencing-Based Genetic Kidney Disease Testing in Kidney Transplant Candidates: Experience at an Urban US Transplant Center.

Recent studies suggest that approximately 10% of patients with chronic kidney disease (CKD) have disease-causing genetic variants, an observation relevant to evaluation of kidney transplant candidates. We retrospectively investigated the diagnostic yield of genetic testing in kidney transplant candidates evaluated at our program (January 1, 2021-December 8, 2022). Inclusion criteria were as follows: first-degree relative(s) with CKD/end-stage kidney disease (ESKD), early-onset CKD, focal segmental glomerulosclerosis, cystic kidney disease, alternative complement pathway-associated diseases, or ESKD of unknown cause. One hundred eleven patients underwent genetic kidney disease testing. The most common indication for testing was early-onset CKD (34.2%), followed by a family history of CKD (23.4%), focal segmental glomerulosclerosis (18.0%), cystic kidney disease (9.0%), alternative complement pathway diseases (3.6%), and ESKD of unknown cause (11.7%). Overall diagnostic yield was 46.9% (52/111), and yield was highest among candidates with a family history of CKD (61.5%; 16/26). Among cases with positive testing, the most common diagnostic variant was APOL1, with 2 renal risk variants identified in 57.7% (30/52), while monogenic causes of CKD were identified in 42.3% (22/52). Genetic testing led to further evaluation or to a different diagnosis than the initial clinical diagnosis in 8.1% (9/111) of the cohort. For 24 transplant candidates, their identified diagnostic variants indicated the need for genetic testing of related living donor candidates; of these, 6 living donor candidates were evaluated and underwent testing, of whom donation was excluded in 1 candidate. Pretransplant genetic testing increases understanding of CKD cause, and provides information for living donor evaluation and risk assessment of posttransplant disease recurrence.

Bosniak Classification of Cystic Renal Masses Version 2019: Proportion of Malignancy by Class and Subclass-Systematic Review and Meta-Analysis.

Background: Bosniak classification version 2019 (v2019) was a major revision to version 2005 (v2005) that defined cystic renal mass subclasses based on wall or septa features. Objective: To determine the proportion of malignancy within cystic renal masses stratified by Bosniak classification v2019 class and feature-based subclass. Evidence Acquisition: MEDLINE and EMBASE databases were searched on July 24, 2023 for studies published in 2019 or later that reported cystic renal masses that underwent renal-mass CT or MRI, were assessed using Bosniak v2019, and had a reference standard (histopathology indicating benignity or malignancy or ≥5-year imaging follow-up indicating benignity). Study authors were contacted to provide subclass-stratified data. Pooled proportions of malignancy stratified by v2019 class and subclass were determined using meta-analysis. Evidence Synthesis: The analysis included 12 studies reporting 966 patients with 975 cystic masses. No class I mass was malignant. Pooled proportions of malignancy by class were: II, 9% (95% CI: 5-17%); IIF, 26% (95% CI: 13-46%); III, 80% (95% CI: 71-87%); IV, 88% (95% CI: 83-91%). Pooled proportions of malignancy by subclass were: IIF with many smooth, thin septa, 10% (95% CI: 2-33%); IIF with minimal wall or septal thickening, 47% (95% CI: 18-77%); IIF with heterogeneous T1-weighted hyperintensity, 26% (95% CI: 8-57%); III with thick smooth wall or septa, 78% (95% CI: 60-90%); III with obtuse protrusion(s) ≤3 mm, 84% (95% CI: 77-90%); IV with acute protrusion(s) of any size, 88% (95% CI: 80-93%); IV with obtuse protrusion(s) ≥4 mm, 86% (95% CI: 77-91%). Proportion of malignancy was 41% for IIF masses with histopathology reference versus 2% for IIF masses with imaging follow-up reference. In four studies performing intraindividual comparisons of v2005 versus v2019, proportion of malignancy was: IIF, 24% versus 42% (p=.13); III, 74% versus 77% (p=.72); IV, 79% versus 84% (p=.22) Conclusion: Bosniak IIF masses had higher malignancy rates when histopathology rather than imaging follow-up was the reference standard, indicating verification bias. All Bosniak III and IV subclasses had high malignancy rates. Clinical Impact: The results improve understanding of imaging-based cystic renal mass classification and may inform development of future renal mass classification systems.

Factors Affecting the Presence of Renal Cortical Cysts in Kidney Donors.

Simple renal cysts (SRCs) represent the most frequently occurring type of renal cysts, frequently observed in the elderly population. While generally considered benign, SRCs may sometimes be connected to comorbid conditions such as hypertension, aortic diseases, and renal dysfunction. This research aims to investigate the factors influencing the development of SRCs in kidney donors and the associated risks. This retrospective cohort study included 1012 living kidney donors, aged 18-87 years, who underwent renal transplant donor nephrectomy between 2008 and 2023. Data on demographic information, cyst characteristics, comorbidities, and associated risk factors were collected and analyzed using statistical methods, including Binary Logistic Regression Analysis. Renal cysts were identified and classified using computed tomography (CT) and magnetic resonance imaging (MRI) methods. Renal cortical cysts were more frequently observed in males (52.76%) compared to females (47.24%), with a significant difference (P=.031). Donors with renal cortical cysts were significantly older (mean age 54.43 ± 12.17 years) compared to those without cysts (46.26 ± 12.35 years, P < .001). Substantial differences were likewise noted in fasting blood glucose, uric acid, creatinine, HbA1c, and glomerular filtration rate (GFR). The prevalence of aortic atherosclerosis was notably elevated in donors with cysts (47.74%) compared to those without (23.57%, P < .001). Binary logistic regression analysis indicated that older age and being male were significant factors influencing the presence of cortical cysts. The study confirms that SRCs are the most common renal cyst type and are more frequently observed in the elderly population. While generally benign, SRCs may be associated with increased uric acid levels and other comorbidities, suggesting potential impacts on kidney health. Additional studies are required to investigate these associations. The presence of SRCs in kidney donors is significantly associated with male gender, age, uric acid levels, and creatinine levels. These findings should be considered during the evaluation of potential kidney donors, particularly regarding the associated risks and management of SRCs.

The ift140 -Deficient Zebrafish: A Model for Renal Cystogenesis and an F0-Based Screen to Identify Genetic Modifiers of Kidney Cysts.

Genetic modifiers are believed to play an important role in the onset and severity of polycystic kidney disease (PKD), but identifying these modifiers has been challenging due to the lack of effective methodologies. In this study, we investigated zebrafish mutants of IFT140 , a newly identified ADPKD gene, and observed phenotypes similar to those seen in mammalian models, including kidney cysts and bone defects. Using efficient microhomology-mediated end joining (MMEJ)-based genome editing technology, we demonstrated that ift140 CRISPRants recapitulate mutant phenotypes while bypassing the early lethality of the mutants to allow for renal cyst analysis in adult fish. In addition to cilia defects, non-cilia phenotypes, such as disrupted cell polarity and aberrant microtubule stabilization in kidney epithelial cells, may also contribute to ift140 -associated cystogenesis. Importantly, the ability to detect ift140 -associated renal cysts with ease allowed us to develop an F0-based genetic screen to identify potential protective modifiers. A pilot screen of sixteen genes previously linked to dysregulated signaling pathways in ADPKD revealed both known and novel modifiers, including mtor and ulk1a . Inhibition of mtor and ulk1a reversed both cilia-related and non-cilia-related abnormalities. In summary, our study underscores the potential of using zebrafish as a model for the efficient discovery of genetic modifiers of kidney cysts.

A Novel Heterozygous and Pathogenic Variant of the HNF1B Gene Associated with Autosomal Dominant Tubulointerstitial Kidney Disease with a Broad Spectrum of Extrarenal Phenotypes: A Case Report.

We encountered a family with hereditary renal failure, renal medullary cysts, pancreatic hypoplasia, hypomagnesemia, liver enzyme abnormalities, and diabetes mellitus (DM). We identified a novel heterozygous variant of HNF1B (NM_000458.4:c.791dup, p.L264Ffs*30) using whole-exome sequencing of genomic DNA samples from this family. This variant is located in the DNA-binding domain of the HNF1B protein and produces a truncated protein with a de novo sequence, suggesting that this variant changes HNF1B binding to genomic DNA or causes nonsense-mediated mRNA decay. Based on the phenotypes and identified gene variants, this family suffers from autosomal dominant tubulointerstitial kidney disease caused by this HNF1B variant.

Differentiation between complex renal cyst and renal cell carcinoma by MRI, diffusion weighted imaging and apparent diffusion coefficient in comparison with histopathology

Background. The most frequent renal masses that are accidentally discovered during abdominal radiological imaging for various clinical causes are renal cysts. MRI used to visualize the kidneys and staging tumors in local setting. DWI and ADC maps become more familiar and has gained a definitive roles in the evaluation of renal masses. The study aimed to evaluate the radiological findings of complex renal cysts and renal cell carcinoma and to differentiate between these lesions by MRI, DW-MRI and ADC in comparison with histopathology. Methods. A comparison combine prospective-retrospective study of 18 individuals with renal lesions were enrolled in this study using MRI, DWI and ADC during a period from 26th July 2023 to 29th May 2024. Participants data included age, sex, MRI mass size, DWI, ADC maps diagnosis by MRI and histopathology diagnosis. MRI was done at 1.5 Tesla (MR Systems Achieva 1.5T TX, Philips, Netherlands). MRI findings were analyzed by two professional specialist radiologist have more than 15 years' experience. DWI diffusion in enhancing lesions was recorded and ADC maps were obtained. All lesions were proven histopathologically. Results. The most of masses were malignant (13, 72.2%) while benign masses were 5 (27.8%). The overall mean ADC of masses was 1.45± 1.28 × 10-3 mm2/s (median = 1.08 × 10-3 mm2/s). Abscesses were recorded in 3 (16.7%) patients. RCC found in 8 (44.4%) of patients, which proven by histopathology. The mean ADC was greater in benign masses than malignant masses (2.58±2.16 vs. 1.02±0.15 × 10-3 mm2/s) with strong significant difference (p=0.014). The mean ADC for the 5 benign masses were: (0.97 × 10-3 mm2/s ±0.31) for abscesses and (2.99 × 10-3 mm2/s ±0.68) for complex cyst. The mean ADC for the 13 malignant masses were as followed: RCC (1.07 × 10-3 mm2/s ±0.08), Oncocytoma (1.07 × 10-3 mm2/s ±0.007), Lymphoma (0.635 × 10-3 mm2/s) and Nephroplastoma (0.80 × 10-3 mm2/s). The ADC cut off value was (1.07 × 10-3 mm2/s), with a sensitivity of 84.62% and specificity of 80.00%. Accuracy rate was 83.33%, which was statistically significant (95%CI (0.152-0.972), P&lt;0.001), and the AUC was (0.562). Conclusions. Most of renal masses detected by MRI are malignant than benign. The most common malignant lesion is RCC and the most common benign lesion is abscesses. The differentiation between malignant and benign renal masses by MRI-DWI and ADC is equally in effectiveness of histopathology diagnosis. Significantly, the mean ADC was greater in benign masses than malignant masses (2.58±2.16 vs. 1.02±0.15 × 10-3 mm2/s). The complex cyst has greatest mean ADC value (2.99 × 10-3 mm2/s ±0.68). The mean ADC in RCC is higher than Oncocytoma, Lymphoma and Nephroplastoma. All malignant lesions have high DW and all are restricted.

A CASE OF CYSTIC SISTERS

Autosomal Dominant Polycystic Kidney Disease or ADPKD is a common cause of renal cysts, which many a times can compromise renal function thus leading to chronic renal failure. It can occur in adjunct with cysts in other organs like liver, which have a sexual predilection for females. Positive family history is a key in making diagnosis of such inherited cystic disorders, especially in low economy settings in a country like India.

Variant Spectrum of Renal Ciliopathies in Turkish Cohort and Genotype-Phenotype Association Specifically in Autosomal Dominant Polycystic Kidney Disease.

Renal ciliopathies are a genetically and phenotypically heterogeneous group of diseases characterized by cystic and dysplastic kidneys. The aim of this study was to investigate the correlation between genetic changes that cause renal ciliopathies and phenotypic outcomes. The study group consisted of 137 patients diagnosed with renal ciliopathy disease. One hundred nineteen patients had ADPKD phenotype, 7 patients had ARPKD phenotype, 4 patients had nephronophthisis, 1 patient had Senior-Loken syndrome, 4 patients had Bardet-Biedl syndrome, 1 patient had Joubert syndrome and 1 patient had Meckel Gruber syndrome phenotype. Among patients with autosomal dominant polycystic kidney disease, patients with the PKD1 gene mutation had higher creatinine levels (p value: 0.020) and no arachnoid cysts were revealed in the PKD2 group (p value: 0.014). When the domains were compared, the finding of arachnoid cyst in patients with mutations in the transmembrane domain was statistically significant (p value: 0.021). Homozygous likely pathogenic variant in the TCTN1 gene was reported in a fetus who had findings of Meckel-Gruber syndrome; microphthalmia and cardiac hypoplasia were reported as novel findings. As a conclusion, we identified variant spectrum of renal ciliopathies in Turkish cohort and revealed the association between the transmembrane domain and arachnoid cyst.

Clinical Spectrum and Prognosis of Atypical Autosomal Dominant Polycystic Kidney Disease Caused by Monoallelic Pathogenic Variants of IFT140.

Monoallelic predicted Loss-of-Function (pLoF) variants in IFT140 have recently been associated with an autosomal dominant polycystic kidney disease (ADPKD)-like phenotype. This study sought to enhance the characterization of this phenotype. Case series. Seventy-five among 2797 European individuals with ADPKD-like phenotypes who underwent genetic testing that revealed pLoF IFT140-variants. The 75 individuals (median age 56 years, 53.3% females) were from 61 families and were found to have 41 different monoallelic pLoF IFT140-variants. The majority of individuals presented with large, exophytic kidney cysts (median [range] total kidney volume 688 ml [201-4139]), and 90.2% were classified using the Mayo Imaging Classification as Mayo Class 2A. Arterial hypertension was present in 50.7% of the individuals (median [range] age at diagnosis 59 years [29-73]). Only one patient developed kidney failure (at age 69 years). A significant difference in age-adjusted eGFR between male and female patients was observed (P<0.001). 56.3% of the individuals over the age of 60 years had an eGFR less than 60ml/min/1.73m2. The estimated genetic prevalence of monoallelic pLoF IFT140 variants was 19.76 (95%CI=18.8-20.7) and 27.89 (95%CI=23.8-31.9) per 10,000 in the Genome Aggregation Database and the 100,000 Genomes Project (100kG), respectively. CyKD (ICD-10 Q61) was associated with pLoF IFT140 variants (P=2.9x10-9, OR=5.6 (3.3-9.2)) only in 100kG. Retrospective study; younger patients and patients with milder forms of IFT140-related CyKD may not be diagnosed. Individuals with monoallelic IFT140 pLoF variants are likely to develop kidney cysts atypical of classical ADPKD and generally have a favorable kidney prognosis.

A Rare Complication After Renal Cyst Aspiration: Distal Catheter Fragment Remaining Within the Cyst Wall and Laparoscopic Treatment

A Rare Complication After Renal Cyst Aspiration: Distal Catheter Fragment Remaining Within the Cyst Wall and Laparoscopic Treatment

Эпидермоидная киста почки: клиническое наблюдение

Abstract. Epidermal cyst is a benign neoplasm, that mostly occurs on the skin.Renal epidermoid cyst has a rare clinical presentation, which in turn complicates preoperative diagnostics and presents difficulties in distinguishing it with malignant renal neoplasms. There are less than twenty cases of renal epidermal cysts and in the most cases either radical or partial nephrectomy was performed. We report a case of a 52 year old man with a histologically confirmed renal epidermoid cyst, that was treated with partial nephrectomy. The patient was asymptomatic and the lesion was accidental finding on the CT scan.

Somatic mutation in autosomal dominant polycystic kidney disease revealed by deep sequencing human kidney cysts

Autosomal Dominant Polycystic Kidney Disease (ADPKD) results in progressive cysts that lead to kidney failure, and is caused by heterozygous germline variants in PKD1 or PKD2. Cyst pathogenesis is not definitively understood. Somatic second-hit mutations have been implicated in cyst pathogenesis, though technical sequencing challenges have limited investigation. We used unique molecular identifiers, high-depth massively parallel sequencing and custom analysis techniques to identify somatic second-hit mutations in 24 whole cysts from disparate regions of six human ADPKD kidneys, utilising replicate samples and orthogonal confirmation. Average depth of coverage of 1166 error-corrected reads for PKD1 and 539 reads for PKD2 was obtained. 58% (14/24) of cysts had a detectable PKD1 somatic variant, with 5/6 participants having at least one cyst with a somatic variant. We demonstrate that low-frequency somatic mutations are detectable in a proportion of cysts from end-stage ADPKD human kidneys. Further studies are required to understand the drivers of this somatic mutation.

Clinical value of contrast-enhanced ultrasound combined with quantitative analysis in Bosniak ≥ II cystic renal masses.

The 2019 Bosniak classification has improved the precise and detailed quantitative evaluation criteria, making the diagnosis of cystic renal masses (CRMs) more accurate and objective. This study addresses the clinical value of quantitative analysis and aims to investigate the feasibility of combining contrast-enhanced ultrasound (CEUS) with quantitative analysis for diagnosing Bosniak ≥ II CRMs. We retrospectively obtained 58 CRMs with confirmed pathology, which underwent CEUS and Contrast-enhanced computer tomography (CECT) evaluations according to Bosniak classification between January 2013 and August 2024. These lesions were divided into benign and malignant groups, followed by a quantitative analysis of the morphological details detected by CEUS. All morphological parameters were compared, and the diagnostic efficiencies were evaluated using receiver operating characteristics (ROC) curves, logistic regression (LR) analysis, and diagnostic curve analysis (DCA). Additionally, a cohort of 72 lesions was monitored for a period of ≥ 3years, and changes in Bosniak classification were analyzed by categorizing them into stable, upgraded, and downgraded categories. The analysis revealed no statistically significant difference between CEUS and CECT in our cohort's malignancy predictive rates across different Bosniak grades (p = 0.640). All morphological quantitative parameters showed statistically significant differences between the two groups (p < 0.001). ROC curve analysis revealed that the sum of enhanced wall thickness and enhanced septum thickness among quantitative parameters had the highest AUC value (AUC: 0.9226). Both LR models demonstrated superior clinical diagnostic performance with similar level of accuracy between qualitative and quantitative analysis, as evidenced by ROC (AUC: 0.9470, 0.9619, respectively) and DCA analyses. None of the lesions in the follow-up cohort were upgraded, suggesting that CRMs are relatively stable tumors with a low malignant potential. This retrospective study demonstrated that CEUS combined with Bosniak classification and quantitative analysis could enhance diagnostic confidence in differentiating Bosniak ≥ II CRMs and could serve as a viable alternative to CECT in specific cases.

KidneyNet: A Novel CNN-Based Technique for the Automated Diagnosis of Chronic Kidney Diseases from CT Scans

This study presents KidneyNet, an innovative computer-aided diagnosis (CAD) system designed to identify chronic kidney diseases (CKDs), such as kidney stones, cysts, and tumors, in CT scans. KidneyNet utilizes a convolutional neural network (CNN) structure consisting of eight convolutional layers, three pooling layers, a flattening layer, and two fully connected layers. Small filters enhance computational efficiency by reducing the number of parameters and minimizing the risk of overfitting compared to larger filters. The model captures more complex and abstract features as data move through the layers. The initial layers identify basic patterns, while the deeper layers focus on more intricate representations. KidneyNet aims to enhance the efficiency and accuracy of kidney disease diagnosis. Additionally, the model incorporates the gradient-weighted class activation mapping (Grad-CAM) algorithm, which helps to pinpoint affected areas in the scans. This feature improves interpretability, allowing clinicians to identify which regions the model deemed significant for detecting abnormalities such as tumors, cysts, or stones. Through extensive testing on a CT kidney dataset, KidneyNet demonstrated impressive performance metrics, with 99.88% accuracy, 99.92% specificity, 99.76% sensitivity, 99.58% precision, and an F1 score of 99.67%, outperforming existing models. This approach alleviates the diagnostic burden on radiologists and promotes early detection, potentially saving lives. This study highlights the critical role of advanced imaging analysis in addressing kidney conditions and emphasizes KidneyNet’s capability to deliver precise and cost-effective diagnoses.

Challenging the narrative of alport syndrome spectrum: no link with cystic phenotype.

Alport Syndromes (AS) are the second leading genetic cause of Kidney Failure (KF). Whether multiple kidney cysts (MKC) phenotype belongs to the AS spectrum remains debated. This multicenter retrospective study focused on patients genotyped with pathogenic COL4A3, COL4A4, or COL4A5 variants (classified as ACMG-AMP 4 or 5) between January 2011 and January 2023 across four French university hospitals. The study aimed to compare characteristics between two groups based on the presence or absence of MKC, defined by three or more cysts per kidney. The MKC group was compared to a control group with negative exome sequencing results for undetermined kidney disease (ES-UKD) to assess the association between MKC and AS. Among the 257 AS patients included, 38 (14.8%) presented MKC without variation from hereditary cystic kidney panel. MKC showed a significant association with male gender (p=0.004), cardiovascular risk factors, and loss of function variants (p=0.012). KF onset appeared significantly later, by 6 years, in MKC patients (p=0.035). Comparison with ES-UKD (n=990) control group showed no significant association between AS and MKC by univariate and multivariate analysis. Multivariate analysis identified patient age and male gender (p<0.001) as factors linked to MKC. A 14.8% prevalence of MKC was found in our cohort of 257 patients with AS. MKC-AS patients exhibited clinical and histological characteristic akin to nephroangiosclerosis. Our comprehensive analysis, incorporating a sizable ES-UKD cohort, revealed no significant association between MKC and AS, thus questioning the inclusion of MKC within the spectrum of AS.

Hyperosmolality activates polycystin-2 and TRPM4 in renal primary cilium.

Autosomal dominant polycystic kidney disease (ADPKD) is a debilitating disease characterized by renal cysts. It arises from mutations in proteins expressed in part in the primary cilia of renal epithelial cells. One of these, polycystin-2 (PC2), is an ion-conducting channel. To date, ion channels in the cilium have only been characterized in standard normosmolar external solutions, but the osmolality of the renal filtrate bathing the cilia varies widely. Here I report that urine, which better represents the filtrate, activates a large cation-conducting current in the cilia. With defined external solutions, hyperosmolality through addition of urea, NaCl, or D-mannitol activates a similar current. Most but not all of this current is conducted through TRPM4 channels. It is greatly reduced by internal MgATP or 9-phenanthrol, which inhibit TRPM4, or by shRNA knockdown of TRPM4. However, part of the current activated by urea conducts Ca2+ through channels that remain to be identified. External hyperosmolality also greatly increases the activity of ciliary PC2 channels; this is the first physiological stimulus identified for these channels. Possibilities are discussed for the mechanisms of channel activation and the roles for these activities in regulatory volume increase and cystogenesis.