Renal cell carcinoma in an adult-onset ESRD patient with nephronophthisis harboring NPHP3 deletion: A case report

Background

Nephronophthisis (NPHP) is a rare autosomal recessive inherited tubulointerstitial nephropathy, the most prevalent genetic cause of end-stage renal disease (ESRD) in children. Convincing evidence indicated that the overall prevalence of NPHP in adult-onset ESRD is very likely to be an underestimation. Therefore, understanding the genetic background and clinicopathologic features of adult-onset NPHP is warranted.

Case presentation

we reported one intriguing case with concurrent NPHP3 c.2694-2_2694-1delAG (splicing) variant and c.1082C > G (p.S361C) variant. A 48-year-old male was admitted to our hospital, complained about renal dysfunction for 10 years, and found right renal space-occupying lesion for 1 week. One of the most interesting clinical features is adult-onset ESRD, which differs from previous cases. Another discovery of this study is that the NPHP harboring NPHP3 deletion may be associated with clear cell renal cell carcinoma.

Conclusion

In conclusion, we report two mutations in the NPHP3 gene that cause NPHP with adult-onset ESRD and renal clear cell carcinoma in a Chinese family, enriching the clinical features of NPHP.

Late-onset Cholestasis with Paucity of Portal Area Secondary to HNF1β Deficiency in Adulthood: A Case Report

Hepatocyte nuclear factor 1β (HNF1β) is essential for biliary development, while its genetic defect triggers the dysplasia of interlobular bile ducts, leading to life-threatening hepatitis and cholestasis. To date, this disorder has mainly been documented in neonates. Here, we report a case of cholestasis in an adult patient caused by a de novo HNF1β mutation. A liver biopsy revealed remarkable shrinkage of the portal area accompanied by a decrease or absence of interlobular bile ducts, veins, and arteries in the portal area. Our case showed that an HNF1β defect could induce late-onset cholestasis with paucity of the portal area in adulthood.

Clinical and molecular characteristics of two Italian kindreds with hypoparathyroidism, deafness and renal dysplasia (HDR) syndrome

PURPOSE

Hypoparathyroidism, deafness, and renal dysplasia (HDR) syndrome, also known as Barakat syndrome, is a rare autosomal dominant disease characterized by the triad of hypoparathyroidism, deafness, and renal abnormalities. The disorder is caused by the haploinsufficiency of the zinc finger transcription factor GATA3 and exhibits a great clinical variability with an age-dependent penetrance of each feature. We report two unrelated kindreds whose probands were referred to our outpatient clinic for further evaluation of hypoparathyroidism.

METHODS

The proband of family 1, a 17-year-old boy, was referred for severe hypocalcemia (5.9 mg/dL) incidentally detected at routine blood tests. Abdomen ultrasound showed bilateral renal cysts. The audiometric evaluation revealed the presence of bilateral moderate hearing loss although the patient could communicate without any problem. Conversely, the proband of family 2, a 19-year-old man, had severe symptomatic hypocalcemia complicated by epileptic seizure at the age of 14 years; his past medical history was remarkable for right nephrectomy at the age of 4 months due to multicystic renal disease and bilateral hearing loss diagnosed at the age of 18 years.

RESULTS

Based on clinical, biochemical, and radiologic data, HDR syndrome was suspected and genetic analysis of the GATA3 gene revealed the presence of two pathogenetic variants in exon 3, c.404dupC and c.431dupG, in the proband of family 1 and 2, respectively.

CONCLUSION

HDR syndrome is a rare cause of hypoparathyroidism and must be excluded in all patients with apparently idiopathic hypoparathyroidism. A correct diagnosis is of great importance for early detection of other HDR-related features and genetic counseling.

A clinical review of congenital hepatic fibrosis diagnosed in adulthood: presentation, complications, and outcomes

INTRODUCTION AND OBJECTIVES

Congenital hepatic fibrosis (CHF) is a rare condition characterized by biliary tract changes and a geographic pattern of liver fibrosis. Liver biopsy is essential to confirm its diagnosis. The absence of specific clinical indicators in adults often leads to delays in diagnosis and management, while the natural history has not been well described. We sought to define the presentation and outcomes of adults with biopsy-proven CHF.

MATERIALS AND METHODS

A retrospective chart review was conducted of patients diagnosed with CHF by liver biopsy. Continuous variables were summarized with the sample median and range. Categorical variables were summarized with number and percentage of patients.

RESULTS

We identified 24 patients evaluated over a 20-year period, with a median age of 51 years (range 22-72 years) at initial presentation; 14 were male. The most common imaging findings were renal cysts (91.3%), splenomegaly (69.6%), and a cirrhotic-appearing liver (60.9%). The most commonly treated liver-related complications were cholangitis (45.8%), varices (45.8%), and hepatic encephalopathy (25%). Two patients died with a median length of follow-up of 2.9 years (range: 0.0-20.0 years). Two patients underwent transjugular intrahepatic portosystemic shunt (TIPS) placement to manage bleeding esophageal varices. Eight patients underwent liver transplantation (LT), the most common indication being decompensated disease (50%).

CONCLUSIONS

CHF should be considered when patients present with cholangitis and/or complications of portal hypertension and have a cirrhotic appearing liver and renal cysts on imaging. Depending upon the disease severity, interventions such as TIPS or LT may be required.

Ciliary ARL13B inhibits developmental kidney cystogenesis in mouse

ARL13B is a small GTPase enriched in cilia. Deletion of Arl13b in mouse kidney results in renal cysts and an associated absence of primary cilia. Similarly, ablation of cilia leads to kidney cysts. To investigate whether ARL13B functions from within cilia to direct kidney development, we examined kidneys of mice expressing an engineered cilia-excluded ARL13B variant, ARL13BV358A. These mice retained renal cilia and developed cystic kidneys. Because ARL13B functions as a guanine nucleotide exchange factor (GEF) for ARL3, we examined kidneys of mice expressing an ARL13B variant that lacks ARL3 GEF activity, ARL13BR79Q. We found normal kidney development with no evidence of cysts in these mice. Taken together, our results show that ARL13B functions within cilia to inhibit renal cystogenesis during mouse development, and that this function does not depend on its role as a GEF for ARL3.

Reprint of: lessons from histopathologic examination of nephrectomy specimens in patients with tuberous sclerosis complex: cysts, angiomyolipomas & renal cell carcinoma

Renal manifestations in patients with tuberous sclerosis complex (TSC) include cysts, angiomyolipoma, and renal cell carcinoma. Unlike many hereditary predisposition syndromes, the spectrum of renal tumors in TSC patients (including both angiomyolipoma and renal cell carcinoma) is broad, with significant morphologic heterogeneity. An improved understanding of histopathologic findings in TSC patients and associated clinicopathologic correlates has significant implications not just in establishing a diagnosis of TSC, but also in the recognition of sporadic tumors occurring secondary to somatic alterations of TSC1/TSC2/MTOR pathway genes and accurate prognostication. In this review, we have discussed issues relevant to clinical management based on histopathologic findings in nephrectomy specimens from patients with TSC. This includes discussions related to screening for TSC, diagnosis of PKD1/TSC2 contiguous gene deletion syndrome, the morphologic spectrum of angiomyolipoma and renal epithelium-derived neoplasia, including the risk of disease progression.

Suspected Autosomal Recessive Polycystic Kidney Disease but Cerebellar Vermis Hypoplasia, Oligophrenia Ataxia, Coloboma, and Hepatic Fibrosis (COACH) Syndrome in Retrospect, A Delayed Diagnosis Aided by Genotyping and Reverse Phenotyping: A Case Report and A Review of the Literature

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.

Assessment of Contrast-Enhanced Ultrasound (CEUS) and Computed Tomography (CT) diagnostic accuracy in the evaluation of challenging cystic renal masses

PURPOSE

To assess the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) and computed tomography (CT) within Bosniak IIF/III categories.

METHODS

After cystic renal mass diagnosis by contrast-enhanced CT, all patients with Bosniak score ≥ II also underwent CEUS between March 2017 and March 2019. Their exams were retrospectively analyzed. One experienced uro-radiologist performed every CEUS and reviewed the exams according to the EFSUMB 2020 Position Statement, while blinded to clinical data. CT Bosniak scores were retrospectively given blindly by two uro-radiologists (CT 1 and CT 2). We compared CEUS, CT 1 and CT 2 scores to clinical findings and histological tests. Clinical performance characteristics and area under the receiver operating characteristic (ROC) curves (AUCs) were determined separately for CEUS and CT, and then compared.

RESULTS

101 cystic masses were analyzed. In Bosniak categories IIF and III, the AUCs were 0.854 for CT 1, 0.779 for CT 2, and 0.746 for CEUS.

CONCLUSION

Despite some statistical limitations, this study confirms that among cystic renal masses, those classified as Bosniak IIF and III are the most difficult to assess. The diagnostic performances of CEUS and CT are similar within this group. However, in experienced hands, CEUS could be valuable in further evaluation of ambiguous cystic masses, and in more ductile, safer, and cost-effective surveillance of those classified as Bosniak IIF and III. When challenging cystic renal masses occur, CEUS is a useful tool for clinical management and for the follow-up of non-surgical lesions.

Lessons from histopathologic examination of nephrectomy specimens in patients with tuberous sclerosis complex: cysts, angiomyolipomas, and renal cell carcinoma

Renal manifestations in patients with tuberous sclerosis complex (TSC) include cysts, angiomyolipoma, and renal cell carcinoma. Unlike many hereditary predisposition syndromes, the spectrum of renal tumors in TSC patients (including both angiomyolipoma and renal cell carcinoma) is broad, with significant morphologic heterogeneity. An improved understanding of histopathologic findings in TSC patients and associated clinicopathologic correlates has significant implications not just in establishing a diagnosis of TSC, but also in the recognition of sporadic tumors occurring secondary to somatic alterations of TSC1/TSC2/MTOR pathway genes and accurate prognostication. In this review, we have discussed issues relevant to clinical management based on histopathologic findings in nephrectomy specimens from patients with TSC. This includes discussions related to screening for TSC, diagnosis of PKD1/TSC2 contiguous gene deletion syndrome, the morphologic spectrum of angiomyolipoma and renal epithelium-derived neoplasia, including the risk of disease progression.

Prevalence of thoracoabdominal imaging findings in tuberous sclerosis complex

Background

Tuberous sclerosis complex (TSC) results in neurodevelopmental phenotypes, benign tumors, and cysts throughout the body. Recent studies show numerous rare findings in TSC. Guidelines suggest routine abdominal and chest imaging to monitor these thoracoabdominal findings, but imaging is not uniformly done across centers. Thus, the prevalence of many findings is unknown. To answer this, we categorized the clinical reads of 1398 thoracoabdominal scans from 649 patients of all ages in the Cincinnati Children’s Hospital TSC Repository Database.

Results

Typical TSC findings were present in many patients: kidney cysts (72%), kidney fat-containing angiomyolipomas (51%), kidney lipid-poor angiomyolipomas (27%), liver angiomyolipomas (19%), and lung nodules thought to represent multifocal micronodular pneumocyte hyperplasia (MMPH) (18%). While many features were more common in TSC2 patients, TSC1 patients had a higher prevalence of MMPH than TSC2 patients (24% versus 13%, p = 0.05). Many rare findings (e.g., lymphatic malformations and liver masses) are more common in TSC than in the general population. Additionally, most thoracoabdominal imaging findings increased with age except kidney cysts which decreased, with the 0–10 years age group having the highest percentage (69% 0–10 years, 49% 10–21 years, 48% 21 + years, p < 0.001). Finally, in our population, no patients had renal cell carcinoma found on abdominal imaging.

Conclusions

These results show that regular thoracoabdominal scans in TSC may show several findings that should not be ignored or, conversely, over-reacted to when found in patients with TSC. Female sex, TSC2 mutation, and age are risk factors for many thoracoabdominal findings. The data suggest novel interactions of genetic mutation with pulmonary nodules and age with renal cysts. Finally, in agreement with other works, these findings indicate that several rare thoracoabdominal imaging findings occur at higher rates in the TSC population than in the general population. This work supports obtaining detailed thoracoabdominal imaging in patients with TSC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02277-x.

Natural history of simple renal cysts: longitudinal CT-based evaluation

PURPOSE

Simple renal cysts are common benign lesions that arise from the renal parenchyma. Cyst growth can lead to confusion as well as concern from patients and referring providers about the need for imaging follow-up or additional evaluation. The purpose of this study was to evaluate the natural history of simple renal cysts and determine the best metric to characterize cyst evolution.

METHODS

222 simple renal cysts in 182 adults (age = 58.4 ± 6.0 years) were longitudinally evaluated on non-contrast CT examinations over a mean interval of 7.5 ± 2.8 years. Axial long axis, surface area, and volume were evaluated at baseline and follow-up CT examinations. Absolute and percent annualized growth rates were computed between CT studies for each parameter.

RESULTS

At baseline CT examinations, mean (± SD) axial long axis, surface area, and volume measurements were 2.5 ± 1.7 cm, 2.5 ± 4.5 cm², and 17.6 ± 52.5 ml, respectively. On follow-up examinations, measurements were 3.4 ± 2.0 cm, 4.2 ± 5.9 cm², and 34.4 ± 92.3 ml, respectively. Significant differences (p < 0.01) were found between baseline and follow-up values for each parameter. The absolute growth rate of each parameter was + 0.1 ± 0.1 cm/year, + 2.1 ± 3.4 cm²/year, and + 2.0 ± 5.6 ml/year, respectively. The percent annualized growth rate for each parameter was +6.5 ± 7.3%/year, +18 ± 24%/year, and +46 ± 100%/year, respectively. Overall, 86% (190/222) of cysts increased in size over time; most notably 78% (174/222) increased by ≥ 6% in volume per year. None of the simple cysts developed septations or solid components on follow-up examinations.

CONCLUSION

The majority of simple renal cysts increase in size over time, which was not associated with the development of complex features. Surface area and volume are the parameters most indicative of cyst growth or regression over time. In patients with enlarging asymptomatic simple renal cysts, no follow-up imaging is indicated.

Burden of Renal Cysts Imaging: A Survey of Patients among the Greater Plains Collaborative

PURPOSE

Renal cysts are a frequent incidental finding on cross-sectional radiographic imaging. While most cysts are indolent, individuals with such cysts are frequently monitored for interval growth and potential malignant transformation, which is ultimately rare. In this study, we aimed to assess patients' values and preferences (believes and attitudes) about renal cysts.

METHODS

We deployed a cross-sectional survey to a random sample of patients with a diagnosis of renal cysts who were identified by billing code and self-identification. We collected data about demographics, insurance status, family history and overall health, and characteristics of patients with renal cysts. We performed a binary regression analysis (adjusted for age, gender, family history of cancer and kidney disease, and treatment plan for renal cysts) to determine anxiety predictors in patients with renal cysts.

RESULTS

We included 301 respondents in whom billing code and self-identification corresponded; of these, 138 had renal cysts and 163 did not. In an adjusted regression analysis, there was a suggestion that a clear management plan (OR = 0.49, 95% CI [0.22-1.11]) (p value 0.08) may be associated with less anxiety and a family history of renal disease may be associated with more anxiety (OR = 1.94 [0.76-4.94]) (p value 0.17). Family history of cancer also did not significantly predict anxiety (OR = 0.54 [0.24-1.19]) (p value 0.13). All these results were not statistically significant and had wide confidence intervals of the effect estimates make the results imprecise.

CONCLUSION

Findings of this pilot study suggest a clear management plan for the renal cyst(s) management may be associated with a lower level of anxiety, thereby by emphasizing the importance of good communication, patient engagement and evidence-based guidance. More definitive, adequately powered studies are needed to evaluate this finding further. In addition, further studies exploring differences in imaging practices, patient symptomatology and patient engagement by different provider types would be insightful. Ultimately, tools to improve shared decision-making are needed to provide more patient-centered care.

Loss of PKD1 and PKD2 share common effects on intracellular Ca2+ signaling

In polycystic kidney disease (PKD) multiple bilateral renal cysts gradually enlarge causing a decline in renal function. Transepithelial chloride secretion through cystic fibrosis transmembrane conductance regulator (CFTR) and TMEM16A (anoctamin 1) drive cyst enlargement. We demonstrated recently that a loss of PKD1 increases expression and function of TMEM16A in murine kidneys and in mouse M1 collecting duct cells. The data demonstrated that TMEM16A contributes essentially to cyst growth by upregulating intracellular Ca2+ signaling. Enhanced expression of TMEM16A and Ca2+ signaling increased both cell proliferation and fluid secretion, which suggested inhibition of TMEM16A as a novel therapy in ADPKD. About 15 % of all ADPKD cases are caused by mutations in PKD2. To analyze the effects of loss of function of PKD2 on Ca2+ signaling, we knocked-down Pkd2 in mouse primary renal epithelial cells in the present study, using viral transfection of shRNA. Unlike in Pkd1-/- cells, knockdown of PKD2 lowered basal Ca2+ and augmented store-operated Ca2+ entry, which was both independent of TMEM16A. However, disease causing purinergic Ca2+ store release was enhanced, similar to that observed in Pkd1-/- renal epithelial cells. The present data suggest pharmacological inhibition of TMEM16A as a treatment in ADPKD caused by mutations in both PKD1 and PKD2.

Complex renal cysts combined with hemorrhage during crizotinib treatment for ALK-rearranged lung adenocarcinoma

The oral small-molecule tyrosine kinase inhibitor (TKI), crizotinib has been approved as a first-generation anaplastic lymphoma kinase (ALK) inhibitor in treatment of advanced ALK-positive non-small cell lung cancer (NSCLC). Recently, development of complex renal cysts has been reported with crizotinib usage, highlighting the importance of accurate differentiation between complex renal cysts and new metastasis in NSCLC. Here we describe a case study with confirmed EGFR wild-type and ALK-rearranged lung adenocarcinoma who developed complex renal cysts combined with hemorrhage during crizotinib treatment, with no abnormal clinical symptoms or kidney functions observed. Interestingly, without crizotinib treatment termination or reduction, the complex hemorrhagic renal cysts regressed with self-limiting and healing. The combined usage of ultrasound, CT and MRI techniques in the presented case allowed proper monitoring of the internal changes within complex renal cysts. The patient provided written informed consent authorizing publication of clinical case. Thus, better understanding of the imaging features of crizotinib-related renal cysts combined with hemorrhage would avoid misdiagnoses as a new metastatic renal mass or the aggravation of the primary disease, therefore avoiding further invasive investigation.

Comparison of aspiration with sclerotherapy and laparoscopic deroofing for the treatment of symptomatic simple renal cysts: a systematic review and meta-analysis

There are currently several strategies for the treatment of symptomatic simple renal cysts, such as aspiration with sclerosants and laparoscopic deroofing. However, no clear indication exists for choosing between them. Here, we carried out a systematic review and a meta-analysis of studies, which compared symptomatic and radiological success between aspiration with sclerotherapy and laparoscopic deroofing. Results were reported as relative risk (RR) and 95% confidence interval (95% CI) using laparoscopic deroofing as control group. The symptomatic and radiological successes were evaluated by 6 and 3 studies, respectively. Notably, aspiration with sclerotherapy was associated with higher risk of failure than laparoscopic deroofing (RR = 2.82; 95% CI = 1.84–4.31 for symptomatic failure; RR = 8.31; 95% CI = 4.22–16.38 for radiological failure). On the other hand, however, aspiration with sclerotherapy was associated with less frequent complications, shorter treatment duration and post-treatment hospital stay, and lower costs. Thus, our work underlines benefits and drawbacks of each intervention, raising the need for further studies to design guidelines for the management of simple renal cysts.

Approach to Renal Cystic Masses and the Role of Radiology

Most renal masses are benign cysts; a subset are malignant. Most renal masses are incidental findings. Evaluation of renal cysts has evolved with updates to the Bosniak classification system and other guidelines. The Bosniak classification provides detailed definitions and extends the system from computed tomography to MR imaging. This article provides a simple approach to the evaluation of cystic or potentially cystic renal masses. The radiologist is central to this process. Key elements include confirming that a renal lesion is cystic and not solid, determining the need for further characterization by imaging, and judicious application of the Bosniak classification system.

Aspiration-sclerotherapy versus laparoscopic de-roofing in the treatment of renal cysts: which is better?

BACKGROUND

To compare the clinical efficiency between aspiration-sclerotherapy (AS) and laparoscopic de-roofing (LD) in the management of renal cysts through meta-analysis of comparative studies.

METHOD

A comprehensive literature search was performed by PubMed, MEDLINE, Ovid and Web of Science for relevant studies published up to January 2020. The statistical analyses were conducted with Review Manager 5.3.0 and Stata 15.1. The sensitivity analysis was also carried out to confirm the reliability of this Meta-analysis.

RESULTS

Our searches of literature generated 6 studies (1547 patients incorporated) comparing AS with LD in the impacts of renal cyst therapy. Of these, 6 studies contained 1106 and 441 patients who were treated with AS and LD, respectively. The outcome of this meta-analysis indicated that LD group was superior in symptomatic successful rate [Odds Ratio (OR): 0.28; 95%Confidence Interval (CI): 0.09 to 0.86; P = 0.03), radiological successful rate (OR: 0.06; 95%CI: 0.02 to 0.15; P < 0.01) and recurrence rate (OR: 6.08; 95%CI: 2.81 to 13.15; p < 0.01). Nevertheless, AS group had shorter treatment time [Mean Difference (MD):-51.10; 95% CI:-73.01 to - 29.20; p < 0.01]. No statistically significant difference was showed in the rate of complications (OR: 3.19; 95% CI: 0.39 to 25.88; P = 0.28).

CONCLUSIONS

In our meta-analysis, LD had higher symptomatic successful rate, radiological successful rate as well as lower recurrence rate than AS, while the treatment time was longer.

TMEM16A drives renal cyst growth by augmenting Ca2+ signaling in M1 cells

Abstract

Polycystic kidney disease (PKD) leads to continuous decline of renal function by growth of renal cysts. Enhanced proliferation and transepithelial chloride secretion through cystic fibrosis transmembrane conductance regulator (CFTR) and Ca²⁺-activated TMEM16A Cl⁻ channels is thought to cause an increase in cyst volume. Recent work shows the pro-proliferative role of the Ca²⁺ activated Cl⁻ channel TMEM16A (anoctamin 1), and demonstrates the essential contribution of TMEM16A to CFTR-dependent Cl⁻ secretion. The present data demonstrate an increase in intracellular Ca²⁺ ([Ca²⁺]i) signals and Cl⁻ secretion by TMEM16A, in renal collecting duct principle cells from dog (MDCK) and mouse (M1) as well as primary tubular epithelial cells from PKD1−/− knockout mice. M1 organoids proliferated, increased expression of TMEM16A, and secreted Cl⁻ upon knockdown of endogenous polycystin 1 or 2 (PKD1,2), by retroviral transfection with shPKD1 and shPKD2, respectively. Knockdown of PKD1 or PKD2 increased basal intracellular Ca²⁺ levels and enhanced purinergic Ca²⁺ release from endoplasmic reticulum. In contrast, ryanodine receptors were found not to be expressed in mouse renal epithelial cells and caffeine had no effects on [Ca²⁺]i. Ca²⁺ signals, proliferation, and Cl⁻ secretion were largely reduced by knockdown or blockade of TMEM16A. TMEM16A may be therefore important for enhanced Ca²⁺ release from IP₃-sensitive Ca²⁺ stores in polycystic kidney disease.

Key messages

• ADPKD leads to continuous decline of renal function by growth of renal cysts.

• Knockdown of PKD1 or PKD2 increases TMEM16A expression.

• TMEM16A enhanced intracellular Ca²⁺ signals, Cl⁻ secretion, and proliferation.

• TMEM16A contributes to cyst growth in ADPKD.

Electronic supplementary material

The online version of this article (10.1007/s00109-020-01894-y) contains supplementary material, which is available to authorized users.

Small (< 4 cm) Bosniak renal cysts: association of initial fluid percentage and enhancing solid volume thresholds with future lesion behavior

PURPOSE

Evaluate the fluid percentage (FP) and enhancing solid volume (SV) of small (< 4 cm) Bosniak 2F, 3 and 4 renal lesions and the association with Bosniak category at baseline and follow-up.

METHODS

Hospital database was searched from 1/1/2010 to 8/3/2018 for small (< 4 cm) Bosniak 2F, 3 and 4 lesions studied with initial and follow-up C+CT/MRI. Two radiologists blindly assigned Bosniak categories to first and last available studies. One radiologist performed volumetric analysis of each lesion, calculating the FP and SV. Association with Bosniak category was explored.

RESULTS

121 patients (84:37 M:F) were identified with 136 renal lesions (84, 37 and 15 Bosniak category 2F, 3 and 4) and followed for 1-12.3 years (mean 3.5 years). 87% (73/84) of 2F lesions were downgraded or remained stable. 48% (25/52) of 3/4 lesions were downgraded. Higher FP was associated with a lower Bosniak category (p value = 0.0042). Increase in FP was associated with the probability of being downgraded on follow-up (OR 1.03, p value = 0.0036), while increase in fluid volume of lesion was directly associated with change in overall lesion size among lesions that were downgraded (b-estimate = 0.03, p value = 0.0003). All Bosniak 3/4 lesions with initial SV less than 0.05 cc were downgraded.

CONCLUSION

FP and SV are useful quantitative surrogates for Bosniak category and future behavior, respectively. Growth of small renal lesions by an increase in fluid volume and FP leads to a downgrade in Bosniak category. Initial SV less than 0.05 cc in Bosniak 3/4 lesions suggests possible future downgrade.

Renal cyst evolution in childhood: a contemporary observational study

INTRODUCTION

Children with renal cysts often undergo ultrasound (US) monitoring to identify malignant transformation or polycystic kidney disease (PKD). However, the utility of ongoing surveillance is uncertain.

OBJECTIVE

The objective of this study was to assess the natural history of simple or minimally complex cysts and the proportion of progression to autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD), or malignancy.

STUDY DESIGN

The institutional review board approved retrospective chart review at one institution between 2004 and 2014. Eligible patients had ≤3 simple or minimally complex cyst(s) discovered on US without an initial diagnosis of multicystic dysplastic kidney, genitourinary malignancy, ADPKD, or ARPKD. Patient demographics and cyst details were recorded at identification and follow-up visits. Logistic regression was used to examine univariate association between diagnosis of ADPKD/ARPKD and each recorded variable.

RESULTS

Eighty-seven eligible patients were identified. Twenty-two patients were identified antenatally or in the first year of life; the remaining 65 were identified at >1 year of age, median 7.6 years (interquartile range [IQR]: 4.2, 10.6). Most (60/87, 69%) had a solitary cyst at initial US. The median length of follow-up was 4.1 years (IQR: 1.9, 6.8) with median 3 follow-up US (IQR: 2, 5). Eleven patients (12.6%) were diagnosed with ADPKD. One patient (1.2%) was diagnosed with ARPKD. A median 2 follow-up US (IQR: 1, 4) procedures were performed over a median of 2.2 years (IQR: 1.0, 3.9) to obtain diagnoses of ADPKD or ARPKD. No patients developed malignancy.

DISCUSSION

This study's results reveal that children identified to have a small number of simple or minimally complex renal cysts on initial US are unlikely to require additional treatment for these cysts as transformation to PKD or malignant condition is rare. Supporting this are results from literature that although simple cysts in childhood may evolve over time, most do not require any surgical or invasive treatment in the long term. Limitations include retrospective design and single institution.

CONCLUSIONS

Autosomal dominant polycystic kidney disease/autosomal recessive polycystic kidney disease diagnosis occurs early in follow-up evaluation in children with simple or minimally complex cysts. Malignant transformation did not occur in any patients in this study.

PATIENT SUMMARY

This study examines the natural history of renal cysts in childhood. Following up simple renal cysts routinely beyond 2-3 years after initial detection may not be optimal due to the use of limited medical resources.

Not only Alagille syndrome. Syndromic paucity of interlobular bile ducts secondary to HNF1β deficiency: a case report and literature review

Background

paucity of interlobular bile ducts is an important observation at liver biopsy in the diagnostic work-up of neonatal cholestasis. To date, other than in the Alagille syndrome, syndromic paucity of interlobular bile ducts has been documented in four cholestatic neonates with HFN1β mutations. A syndromic phenotype, known as renal cysts and diabetes syndrome (RCAD), has been identified. This is usually characterized by a wide clinical spectrum, including renal cysts, maturity-onset diabetes of the young, exocrine pancreatic insufficiency, urogenital abnormalities and a not well established liver involvement. Herein we report a novel case of paucity of interlobular bile ducts due to an HFN1β defect.

Case presentation

A 5-week-old boy was admitted to our department for cholestatic jaundice with increased gamma-glutamyl transpeptidase and an unremarkable clinical examination. He had been delivered by Caesarian section at 38 weeks’ gestation from unrelated parents, with a birth weight of 2600 g (3rd percentile). Screening for cholestatic diseases, including Alagille syndrome, was negative except for a minor pulmonary artery stenosis at echocardiography and a doubt of a thoracic butterfly hemivertebra. The finding of hyperechogenic kidneys with multiple bilateral cortical cysts at ultrasound examination, associated with moderately impaired renal function with proteinuria, polyuria and metabolic acidosis, was suggestive of ciliopathy. A liver biopsy was performed revealing paucity of interlobular bile ducts, thus the diagnosis of Alagille syndrome was reconsidered. Although genetic tests for liver cholestatic diseases were performed with negative results for Alagille syndrome (JAG1 and NOTCH2), a de-novo missense mutation of HNF1β gene was detected. At 18 months of age our patient has persistent cholestasis and his itching is not under satisfactory control.

Conclusions

Alagille syndrome may not be the only syndrome determining paucity of interlobular bile ducts in neonates presenting with cholestasis and renal impairment, especially in small for gestational age newborns. We suggest that HNF1β deficiency should also be ruled out, taking into consideration HNF1β mutations, together with Alagille syndrome, in next generation sequencing strategies in neonates with cholestasis, renal impairment and/or paucity of interlobular bile ducts at liver biopsy.

Polycystosis of the renal sinus or polycystic kidney disease Controversies, challenges and history of a shared discovery

OBJECTIVE

To recall the history of the discovery of non-nephron cystic disease, detected simultaneously in 2 hospitals in Madrid, and the vicissitudes that the authors endured during the process of recognising this disease, while being ignored by the international scientific literature.

MATERIAL AND METHOD

We analysed the authors' first publications and presentations, their correspondence relaying the difficulties in reporting the confusion with adult polycystic kidney disease (APKD) and the subsequent nosological identification of the process. We consulted with individuals who worked with the 2 authors to increase the accuracy and objectivity of the history report.

RESULTS

We confirmed the authors' remarkable efforts in getting the process definitively recognised despite the notable difficulties.

CONCLUSIONS

Rigorous clinical observation recognises processes ignored by the medical literature, and the correct application of the scientific method helps identify and reveal new nosological entities, confirming with this story's example that, in medicine, there are no exhausted issues.

Prevalence of renal cysts and association with risk factors in a general population: an MRI-based study

PURPOSE

To assess the prevalence and size of renal cysts and to analyze associated risk factors in a general population using magnetic resonance imaging (MRI).

METHODS

Data of 2063 participants (1052 women) of the Study of Health in Pomerania who underwent whole-body MRI were included. Renal cyst prevalence was calculated separately for men and women and for 10-year age groups. The association between risk factors and occurrence of renal cysts was estimated.

RESULTS

The prevalence of renal cysts was 27% and higher in men (34%) than in women (21%; p < 0.001). Renal cyst prevalence increased from 14% in the youngest age group (20-29 years) to 55% in the oldest age group (≥ 70 years) for men and from 7% to 43% for women (both p < 0.001). In the subset of participants with renal cysts, the total mean number was higher in men (1.9) compared to women (1.6, p = 0.012) and was significantly associated with age. Mean renal cyst size was higher in men (1.50 cm) compared to women (1.18 cm, p < 0.001). Male sex (OR 1.83, 95% CI 1.47; 2.26), older age (OR 1.05, 95% CI 1.04; 1.06, per 1-year increment), and hypertension (OR 1.27, 95% CI 1.00; 1.61) were associated with higher renal cyst prevalence. In additional analyses, current smoking and ex-smoking showed a significantly higher risk for renal cysts (OR 1.47, 95% CI 1.05; 2.05 and OR 1.38, 95% CI 1.04; 1.82, respectively).

CONCLUSIONS

The prevalence, number, and mean size of renal cysts are higher in men compared to women and are associated with age. In addition, renal cyst prevalence is higher in hypertensive and smoking subjects.

COL4A5 and LAMA5 variants co-inherited in familial hematuria: digenic inheritance or genetic modifier effect?

BACKGROUND

About 40-50% of patients with familial microscopic hematuria (FMH) caused by thin basement membrane nephropathy (TBMN) inherit heterozygous mutations in collagen IV genes (COL4A3, COL4A4). On long follow-up, the full phenotypic spectrum of these patients varies a lot, ranging from isolated MH or MH plus low-grade proteinuria to chronic renal failure of variable degree, including end-stage renal disease (ESRD).

METHODS

Here, we performed Whole Exome Sequencing (WES) in patients of six families, presenting with autosomal dominant FMH, with or without progression to proteinuria and loss of renal function, all previously found negative for severe collagen IV mutations. Hierarchical filtering of the WES data was performed, followed by mutation prediction analysis, Sanger sequencing and genetic segregation analysis.

RESULTS

In one family with four patients, we found evidence for the contribution of two co-inherited variants in two crucial genes expressed in the glomerular basement membrane (GBM); LAMA5-p.Pro1243Leu and COL4A5-p.Asp654Tyr. Mutations in COL4A5 cause classical X-linked Alport Syndrome, while rare mutations in the LAMA5 have been reported in patients with focal segmental glomerulosclerosis. The phenotypic spectrum of the patients includes hematuria, proteinuria, focal segmental glomerulosclerosis, loss of kidney function and renal cortical cysts.

CONCLUSIONS

A modifier role of LAMA5 on the background of a hypomorphic Alport syndrome causing mutation is a possible explanation of our findings. Digenic inheritance is another scenario, following the concept that mutations at both loci more accurately explain the spectrum of symptoms, but further investigation is needed under this concept. This is the third report linking a LAMA5 variant with human renal disease and expanding the spectrum of genes involved in glomerular pathologies accompanied by familial hematurias. The cystic phenotype overlaps with that of a mouse model, which carried a Lama5 hypomorphic mutation that caused severely reduced Lama5 protein levels and produced kidney cysts.

Contemporary assessment of the correlation between Bosniak classification and histological characteristics of surgically removed atypical renal cysts (UroCCR-12 study)

PURPOSE

To evaluate and compare pathological characteristics of renal cysts Bosniak IIF, III and IV in light of recent histological classification.

PATIENTS AND METHODS

The French research network for kidney cancer UroCCR conducted a multicentre study on patients treated surgically for a renal cyst between 2007 and 2016. Independent radiological and centralized pathological reviews were performed for every patient. Pathological characteristics were compared to the Bosniak classification.

RESULTS

Of a total 216 patients included, 175 (81.0%) tumours (90.9% of Bosniak IV, 69.8% of Bosniak III) were malignant or had a low malignant potential, with 60% of clear cell renal cell carcinoma (CCRCC), 24% of papillary RCC (PRCC) and 6.9% of multilocular cystic renal tumour of low malignant potential (MCRTLMP). Malignancies were mostly of low pT stage (86.4% of pT1-2), and low ISUP grade (68.0% of 1-2). Bosniak III cysts had a lower rate of CCRCC (46.7 vs. 67.3%), higher rate of PRCC (30 vs. 20.9%) and MCRTLMP (18.3 vs. 0.9%) compared to Bosniak IV (p < 0.001). Low-malignant potential lesions were less likely Bosniak IV and pT3-4 stage was more frequent in Bosniak IV vs. III (15.7 vs. 3.5%; p = 0.04). There were two recurrences (1.1%) and no cancer-related death occurred during follow-up.

CONCLUSION

These results confirmed that cystic renal malignancies have excellent prognosis. Bosniak III cysts had a low malignant potential, which suggests surveillance could be an option for these lesions.

Minimally Complex Renal Cysts: Outcomes and Ultrasound Evaluation Compared with Contrast-Enhanced Cross-Sectional Imaging Bosniak Classification

We correlated contrast-enhanced cross-sectional imaging and outcomes to assess the reproducibility of ultrasonographic criteria for renal minimally complex (MC) cysts. From 2003 to 2015, 143 cysts were described as complex or MC by ultrasound (US). After exclusions, 98 US studies were retrospectively evaluated and compared with computed tomography (CT)/magnetic resonance imaging (MRI). At sonography, 51 were MC cysts and 47 were complexes according to two independent observers. Inter-observer agreement for US was 0.704 and 0.745 for CT/MRI. Of 51 cysts classified as MC by US, 38 were Bosniak I/II and 6 were Bosniak IIF by CT/MRI. In 7, there were no cross-sectional images; however, they were stable for at least 2 y. Of 47 complex cysts, 9 were Bosniak II, 22 Bosniak IIF, 8 Bosniak III and 8 Bosniak IV. No Bosniak III/IV cysts by CT/MRI were classified as MC by US. Our results indicate that US offers reproducible criteria for MC cysts and may be used alone for these lesions.

Tesevatinib ameliorates progression of polycystic kidney disease in rodent models of autosomal recessive polycystic kidney disease

AIM

To investigate the therapeutic potential of tesevatinib (TSV), a unique multi-kinase inhibitor currently in Phase II clinical trials for autosomal dominant polycystic kidney disease (ADPKD), in well-defined rodent models of autosomal recessive polycystic kidney disease (ARPKD).

METHODS

We administered TSV in daily doses of 7.5 and 15 mg/kg per day by I.P. to the well characterized bpk model of polycystic kidney disease starting at postnatal day (PN) 4 through PN21 to assess efficacy and toxicity in neonatal mice during postnatal development and still undergoing renal maturation. We administered TSV by oral gavage in the same doses to the orthologous PCK model (from PN30 to PN90) to assess efficacy and toxicity in animals where developmental processes are complete. The following parameters were assessed: Body weight, total kidney weight; kidney weight to body weight ratios; and morphometric determination of a cystic index and a measure of hepatic disease. Renal function was assessed by: Serum BUN; creatinine; and a 12 h urinary concentrating ability. Validation of reported targets including the level of angiogenesis and inhibition of angiogenesis (active VEGFR2/KDR) was assessed by Western analysis.

RESULTS

This study demonstrates that: (1) in vivo pharmacological inhibition of multiple kinase cascades with TSV reduced phosphorylation of key mediators of cystogenesis: EGFR, ErbB2, c-Src and KDR; and (2) this reduction of kinase activity resulted in significant reduction of renal and biliary disease in both bpk and PCK models of ARPKD. The amelioration of disease by TSV was not associated with any apparent toxicity.

CONCLUSION

The data supports the hypothesis that this multi-kinase inhibitor TSV may provide an effective clinical therapy for human ARPKD.

The Role of PET Scanning in the Evaluation of Patients With Kidney Disease

Patients with underlying kidney disease are often required to undergo imaging for a variety of purposes including diagnosis and prognosis. A test that is being increasingly used with for this group of patients is the positron emission test (PET) scan. In addition, combining the nuclear medicine technique (PET) with computed tomography scan allows additional imaging advantages over either alone. These imaging modalities are commonly used for a number of extrarenal indications (ie, cancer, coronary artery disease, central nervous system disease, infectious diseases, and others). They have also been used for diagnosis of acute tubulointerstitial nephritis, evaluation and management of retroperitoneal fibrosis, identifying infection within kidney and liver cysts, and distinguishing complex kidney cysts from kidney cancer in patients with underlying CKD. We will review PET scan utility in patients with kidney disease.

A familial case of severe infantile nephronophthisis explained by oligogenic inheritance

Renal cysts are common malformation during the prenatal and postnatal period and frequent cause of chronic kidney or ESRD. More than 70 genes have been shown to play role in their pathology. Part of them are responsible for the structure and function of the cilia, which assigns a large proportion of the renal cystic diseases in the ciliopathies. Another group of genes responsible for cystic kidneys encodes transcription factors with crucial role during organogenesis. We describe here a systematic approach for identifying the genetic cause(s) of an unusually severe form of renal cystic disease in a family with multiple affected siblings. High throughput mutations screening of the parents and one of the children was applied for identifying the genetic causes of the disease. The affected child was found to have inherited 3 deleterious mutations in two nephronophthisis genes, NPHP3 and NPHP4. The possibility for epistatic interaction of the NPHP mutations as well as the modifying effect of other inherited genetic variants is discussed.

Impact of contrast-enhanced ultrasound in patients with renal function impairment

AIM

To investigate the role of contrast enhanced ultrasound (CEUS) in evaluating patients with renal function impairment (RFI) showing: (1) acute renal failure (ARF) of suspicious vascular origin; or (2) suspicious renal lesions.

METHODS

We retrospectively evaluated patients addressed to CEUS over an eight years period to rule-out vascular causes of ARF (first group of 50 subjects) or assess previously found suspicious renal lesions (second group of 41 subjects with acute or chronic RFI). After preliminary grey-scale and color Doppler investigation, each kidney was investigated individually with CEUS, using 1.2-2.4 mL of a sulfur hexafluoride-filled microbubble contrast agent. Image analysis was performed in consensus by two readers who reviewed digital clips of CEUS. We calculated the detection rate of vascular abnormalities in the first group and performed descriptive statistics of imaging findings for the second group.

RESULTS

In the first group, CEUS detected renal infarction or cortical ischemia in 18/50 patients (36%; 95%CI: 23.3-50.9) and 1/50 patients (2%; 95%CI: 0.1-12), respectively. The detection rate of infarction was significantly higher (P = 0.0002; McNemar test) compared to color Doppler ultrasonography (10%). No vascular causes of ARF were identified in the remaining 31/50 patients (62%). In the second group, CEUS detected 41 lesions on 39 patients, allowing differentiation between solid lesions (21/41; 51.2%) vs complex cysts (20/41; 48.8%), and properly addressing 15/39 patients to intervention when feasible based on clinical conditions (surgery and cryoablation in 13 and 2 cases, respectively). Cysts were categorized Bosniak II, IIF, III and IV in 8, 5, 4 and 3 cases, respectively. In the remaining two patients, CEUS found 1 pseudolesion and 1 subcapsular hematoma.

CONCLUSION

CEUS showed high detection rate of renal perfusion abnormalities in patients with ARF, influencing the management of patients with acute or chronic RFI and renal masses throughout their proper characterization.

Malignancy rates and diagnostic performance of the Bosniak classification for the diagnosis of cystic renal lesions in computed tomography - a systematic review and meta-analysis

Objective

To systematically review the literature on the Bosniak classification system in CT to determine its diagnostic performance to diagnose malignant cystic lesions and the prevalence of malignancy in Bosniak categories.

Methods

A predefined database search was performed from 1 January 1986 to 18 January 2016. Two independent reviewers extracted data on malignancy rates in Bosniak categories and several covariates using predefined criteria. Study quality was assessed using QUADAS-2. Meta-analysis included data pooling, subgroup analyses, meta-regression and investigation of publication bias.

Results

A total of 35 studies, which included 2,578 lesions, were investigated. Data on observer experience, inter-observer variation and technical CT standards were insufficiently reported. The pooled rate of malignancy increased from Bosniak I (3.2 %, 95 % CI 0–6.8, I² = 5 %) to Bosniak II (6 %, 95 % CI 2.7–9.3, I² = 32 %), IIF (6.7 %, 95 % CI 5–8.4, I² = 0 %), III (55.1 %, 95 % CI 45.7–64.5, I² = 89 %) and IV (91 %, 95 % CI 87.7–94.2, I² = 36). Several study design-related influences on malignancy rates and subsequent diagnostic performance indices were identified.

Conclusion

The Bosniak classification is an accurate tool with which to stratify the risk of malignancy in renal cystic lesions.

Key points

• The Bosniak classification can accurately rule out malignancy.

• Specificity remains moderate at 74 % (95 % CI 64–82).

• Follow-up examinations should be considered in Bosniak IIF and Bosniak II cysts.

• Data on the influence of reader experience and inter-reader variability are insufficient.

• Technical CT standards and publication year did not influence diagnostic performance.

Electronic supplementary material

The online version of this article (doi:10.1007/s00330-016-4631-9) contains supplementary material, which is available to authorized users.

MRI evaluation of complex renal cysts using the Bosniak classification: a comparison to CT

PURPOSE

The purpose of this study was to compare the ability of magnetic resonance imaging (MRI) and computed tomography (CT) to discriminate between benign and malignant cystic renal lesions utilizing the Bosniak classification.

MATERIALS AND METHODS

We retrospectively searched our Radiological Information System using renal/kidney cysts as entries. The search retrieved 2929 patients and 525 complex renal cysts. After exclusions, 42 complex cysts, from 37 patients, with CT and MRI, up to six months apart, were included. Surgery and pathology report and follow-up of at least 24 months were used as a standard of reference.

RESULTS

The mean age of patients was 51.4 years, ranging from 11 to 82 years old. Twenty-nine lesions were classified as Bosniak I, II or II-F by CT and/or MRI and 13 as Bosniak III or IV, by one of the methods. The interobserver agreement for Bosniak classification for CT was 0.87 and 0.93 for MRI. Fifteen lesions had higher Bosniak categories on MRI, included six with change in management. Only two lesions had a higher category on CT, one with change in management. The frequency of malignancy for Bosniak III was 50 % (2/4) for CT and 20% for MRI (1/5), as Bosniak upgrades by MRI resulted in surgery for benign lesions. Both methods had 100 % frequency of malignancy for category 4.

CONCLUSION

MRI led to category migration and management change of complex renal cysts in a significant proportion of cases, likely due to its superior soft tissue and contrast resolution. The impact of MRI on detection and outcomes of malignant complex renal cysts still requires further investigation.

Imaging features of renal complications after crizotinib treatment for non-small-cell lung cancer: a case report

Crizotinib has been approved for the treatment of advanced ALK-positive non–small cell lung cancer. Its use is associated with the development of complex renal cysts. However, there is limited literature regarding imaging features of renal cystic disease during crizotinib therapy and its complications or progression. Here, we describe a case of a patient with ALK-positive advanced non–small cell lung cancer who developed complex renal cyst during crizotinib treatment. The renal cyst is complicated by infection and abscess formation. Subsequent renal biopsy, antibiotics treatment, and open drainage of loculated renal abscess showed no malignant cells and contributed to the diagnosis. The imaging features should be recognized as renal cystic disease of crizotinib treatment and not to be mistaken as new metastasis and disease progression.

Clinical and genetic characteristics of Japanese nephronophthisis patients. Clin Exp Nephrol. 2016;20:637-649. [PMID: 26499951 DOI: 10.1007/s10157-015-1180-5]

BACKGROUND

Nephronophthisis (NPH) accounts for 4-5 % of end-stage renal disease occurring in childhood.

METHOD

We investigated the clinical context and characteristics of renal and extrarenal symptoms, as well as the NPHP genes, in 35 Japanese patients with clinical and histologic features suggesting NPH.

RESULTS

NPH occurred fairly uniformly throughout Japan irrespective of region or gender. In three families, NPH affected siblings. The median age of patients was 12.5 years. Renal abnormalities attributable to NPH discovered through mass screening, such as urine tests in school. However, NPH accounted for less than 50 % of children with abnormal findings, including incidentally discovered renal dysfunction during evaluation of extrarenal symptoms or during routine check-ups. Typical extrarenal manifestations leaded to discovery including anemia and delayed physical development. The urine often showed low gravity specific density and low molecular weight proteinuria. Frequent renal histologic findings included cystic dilation of tubules, mainly in the medulla, and irregularity of tubular basement membranes. Genetically abnormalities of NPHP1 were not common, with large deletions frequently noted. Compound heterozygotes showing single abnormalities in each of NPHP1, NPHP3, and NPHP4 were observed.

CONCLUSIONS

Our findings resemble those reported in Western populations.

[Renal cysts - A novel complication of crizotinib treatment for lung cancer]

We report the case of a woman with an ALK positive lung adenocarcinoma, who developed bilateral complex renal cysts 17 months after the introduction of treatment with crizotinib. Clinical investigation led to the conclusion that the cysts were due to anticancer drug. Regression of the renal cysts was observed one month after cessation of the crizotinib. This case illustrates that specific and little known toxicities can occur with these novel molecules which have entered use for the management of lung cancer.

Intensity modulated radiotherapy (IMRT) for patients of the Brazilian unified health system (SUS): an analysis of 508 treatments two years after the technique implementation

The Bosniak classification for renal cysts was developed in the late 1980s in an attempt to standardize the description and management of complex cystic renal lesions. Alterations were made to such a classification in the 1990s and, the last one, in 2005. Currently, five categories of cystic renal lesions are defined - namely, I, II, II-F, III and IV –, according to their degree of complexity and likelihood of malignancy. Despite being initially described for computed tomography, this classification has been also utilized with some advantages also for magnetic resonance imaging. The present article reviews the different phases of this classification, its diagnostic efficacy and the most controversial features of its use.

Bosniak classification for complex renal cysts: history and critical analysis

The Bosniak classification for renal cysts was developed in the late 1980s in an attempt to standardize the description and management of complex cystic renal lesions. Alterations were made to such a classification in the 1990s and, the last one, in 2005. Currently, five categories of cystic renal lesions are defined - namely, I, II, II-F, III and IV –, according to their degree of complexity and likelihood of malignancy. Despite being initially described for computed tomography, this classification has been also utilized with some advantages also for magnetic resonance imaging. The present article reviews the different phases of this classification, its diagnostic efficacy and the most controversial features of its use.

A rare case of a 39 year old male with a parasite called Dioctophyma renale mimicking renal cancer at the computed tomography of the right kidney. A case report

We present a very rare case of a 39 year old patient with Dioctophyma renale depicted as a Bosniak cyst IV of the right kidney who was finally subjected to a robotic assisted radical nephrectomy.

Renal cysts and urinomas

Renal cysts are a common imaging finding. Although most cysts never have symptoms, some cause pain, collecting system compression, hematuria, hypertension, and secondary infection. The mere presence of a cyst is not an indication for intervention, but treatment may be indicated in symptomatic patients or those with secondary obstruction. Urinomas generally are a contained collection of urine outside of the normal pathways where urine travels. As such, urinomas can arise anywhere from the upper abdomen down into the low pelvis and have a variety of etiologies. Ureteral obstruction with forniceal rupture and trauma (blunt, penetrating, or iatrogenic) are the most common causes of urinomas. When urinomas arise spontaneously, the likely cause varies with the patient's age. Blunt or penetrating trauma can cause perinephric urinomas by two mechanisms-direct disruption of the pelvis or collecting system or by degeneration of nonviable tissue. These urinomas are often perinephric, but can also occur in a subcapsular location. This review will discuss diagnosis, classification, and treatment of renal cysts and urinomas.

Acceleration of the meckel syndrome by near-infrared light therapy

Background/Aims

Phototherapy using a narrow-band, near-infrared (NIR) light (using a light-emitting diode, LED) is being used to treat certain medical conditions. This narrow-band red light has been shown to stimulate cytochrome c oxidase (CCO) in mitochondria that would stimulate ATP production and has the ability to stimulate wound healing. LED treatment also decreases chemical-induced oxidative stress in tested systems. As renal cystic diseases are known to have evidence of oxidative stress with reduced antioxidant protection, we hypothesized that NIR light therapy might ameliorate the renal pathology in renal cystic disease.

Methods

Wistar-Wpk/Wpk rats with Meckel syndrome (MKS) were treated with light therapy on days 10–18 at which time disease severity was evaluated. Wpk rats were either treated daily for 80 s with narrow-band red light (640–690 nm wavelength) or sham treated. At termination, renal and cerebral pathology was evaluated, and renal expression and activity of enzymes were assessed to evaluate oxidative stress. Blood was collected for blood urea nitrogen (BUN) determination, the left kidney frozen for biochemical evaluation, and the right kidney and head fixed for morphological evaluation.

Results

There were no significant effects of LED treatment on body weight (BW) or total kidney weight in non-cystic rats. Total kidney weight was increased and anephric BW was decreased in cystic versus non-cystic controls. LED reduced BW and total kidney weight in cystic rats compared to non-light-treated cystic (control) rats. BUN was already increased almost 6-fold in cystic rats compared to control rats. BUN was further increased almost 2-fold with NIR treatment in both non-cystic and cystic rats compared to cystic and control rats. The hydrocephalus associated with Wpk/Wpk (ventricular volume expressed as total volume and as percent of anephric BW) was also more severe in NIR-treated cystic rats compared to the normal control rats. Renal glutathione peroxidase and catalase (CAT) were reduced in the cystic kidney while superoxide dismutase and CCO were increased. NIR increased CAT and CCO, marginally decreased glutathione S-transferase and slightly decreased glutathione reductase in cystic rats compared to the normal control rats. The detrimental effects of NIR may be related to reduced renal blood flow associated with progression of cystic pathology. Compression by cysts may not allow sufficient oxygen or nutrient supply necessary to support the increased oxidative phosphorylation-associated cellular activity, and the increased demand induced by NIR-increased CCO may have created further oxidative stress.

Conclusion

LED phototherapy initiated after the onset of symptoms was detrimental to MKS-induced pathology. NIR stimulates CCO thereby increasing the kidney's need for oxygen. We hypothesize that cystic compression of the vasculature impairs oxygen availability and the enhanced CCO activity produces more radicals, which are not sufficiently detoxified by the increased CAT activity.

Simple renal cysts and circadian blood pressure: are they related to each other in patients with hypertension?

Previous studies have shown that the presence of simple renal cysts was related to hypertension. However, the relationship between simple renal cysts and circadian blood pressure was not studied before. Our study population comprised of newly diagnosed patients with essential hypertension. Medical history, physical examination and office blood pressure measurements, laboratory analysis, ambulatory blood pressure measurements, renal ultrasonography, and 24-h urine specimens were collected. In total, the study included 190 patients (male/female ratio 77/113; mean age 50.3 ± 11.3). Overall, 127 (66.8%) patients were dippers and 92 (48.4%) had at least one simple renal cyst. Thirty-five patients had solitary cysts and 57 patients had multiple cysts. Cysts were bilateral in 47 of patients. Most of ambulatory blood pressure recordings were higher in patients with at least one simple cyst when compared to patients without cysts. In multivariate logistic regression analysis, serum uric acid (P: 0.047, OR: 1.287, CI: 1.011-1.658), lower creatinine clearance (P: 0.001, OR: 1.030, CI: 1.012-1.049), presence of diabetes (P: 0.029, OR: 2.451, CI: 1.094-5.491), and presence of at least one cyst in each kidney (P: 0.002, OR: 3.087, CI: 1.533-6.212) were found to be independently related to nocturnal non-dipping. In conclusion, the presence of simple renal cysts is related to higher ambulatory BP and is associated with non-dipping phenomenon in patients with essential hypertension.