Incidental Renal Cysts Found by Point-of-Care Ultrasound: A Retrospective Chart Review.

BACKGROUND: Incidental findings are unrelated to a patient's complaint, found on diagnostic imaging, such as point-of-care ultrasound (POCUS). Incidental findings represent potential harms to patients and may lead to increased patient anxiety and health care costs related to downstream testing and surveillance. STUDY OBJECTIVES: In this study, we aimed to calculate the rate of incidental renal cysts found by POCUS. Further, we hoped to describe how emergency physicians relay the findings to patients. Lastly, we hoped to examine if patients suffered harms in the 12 months following identification of an incidental renal cyst. METHODS: From our single-center, academic emergency department (ED), we reviewed renal POCUS images from 1000 consecutive adult ED patients to determine if there was a renal cyst. Next, we performed manual chart review to determine if patients were informed of the incidental renal cyst or suffered any patient harms. RESULTS: We found the prevalence of renal cysts to be 6.5% (95% confidence interval: 4.9%-8.4%). Those with cysts were more likely to be older compared to those without (63 ± 14 vs. 49 ± 15 years of age). Only 8% of patients had evidence that they were informed of their incidental renal cyst. No patients received a biopsy or were diagnosed with renal cell carcinoma or polycystic kidney disease. CONCLUSION: Incidental renal cysts are common and are more likely to be found in older adults. In our study, physicians infrequently informed patients of their incidental finding.

Contrast-Enhanced Ultrasound as a Diagnostic Procedure in Renal Diseases: A Case Report.

Standard ultrasound (US) finds wide use in renal diseases as a screening procedure, but it is not always able to characterize lesions, especially in differential diagnosis between benign and malignant lesions. In contrast, contrast-enhanced ultrasonography (CEUS) is appropriate in differentiating between solid and cystic lesions as well as between tumors and pseudotumors. We show the case of a nephropathic patient who showed a complex, large, growing renal mass, characterized through a CEUS. This seventy-five-year-old diabetic heart patient showed a 6 cm-complex and plurisected cyst on ultrasound of left kidney. Laboratory data showed the presence of stage IIIb chronic renal failure with GFR 30 ml/min, creatinine 2.33 mg/dl, azotemia 88 mg/dl. The patient performed abdominal CT without contrast medium, showing at the level of the left upper pole, a roundish formation with the dimensions of approximately 70x53x50 mm. At the semiannual checkup, the nephrology examination showed a slight rise in creatinine and, therefore, after six months, it was decided to perform a CT scan without contrast medium again. CT showed a slight increase in the size of the mass located at the left kidney (74x56x57 mm). Given the increased size of the left mass, albeit modest, a CEUS was performed to reach a diriment diagnosis. CEUS concluded for complex cystic formation with presence of intraluminal solid-corpuscular material, with thrombotic-hemorrhagic etiology, in progressive phase of organization, classifiable as Bosniak type II cyst. CEUS in the kidneys is a cost-effective and valuable imaging technique; it is accurate in the characterization of indeterminate lesions and complex cysts.

Development of crizotinib-associated renal cyst in a non-small cell lung cancer patient with ALK fusion: a case report and review of the literature.

BACKGROUND: Crizotinib, an oral first-generation tyrosine kinase inhibitor (TKI), is superior to systemic chemotherapy for the treatment of non-small cell lung cancer (NSCLC) with positive rearrangement of anaplastic lymphoma kinase (ALK). However, an increased incidence of renal and hepatic cysts has been reported in the patients on crizotinib treatment. CASE PRESENTATION: Here, we describe a case of a 71-year-old Chinese women developed multiple cystic lesions in kidney and liver during crizotinib treatment for the primary and metastatic NSCLC. The renal and hepatic cysts were noted by CT scan 3 months after crizotinib treatment, which were spontaneously and significantly regressed after stopping crizotinib. CONCLUSIONS: Based on literature review and our experience in this case report, we concluded that crizotinib-associated renal cyst (CARCs) has features of malignancy and abscess in radiographic imaging, and thus, pathological confirmation is necessary to avoid inappropriate treatment decision. In addition, to benefit the patients with progress-free survival (PFS), switching from crizotinib to alectinib is recommended for the treatment of NSCLC patients who developed CARCs.

An unusual cause of syncope: Inferior vena cava compression by a massive renal cyst.

Syncope is a commonly encountered symptom that accounts for up to 3% of all emergency department visits in the United States [1]. The differential diagnosis for patients presenting with syncope is often broad and can involve multiple distinct organ systems. This case details the hospital course of an 83-year-old male with a complicated past medical history who initially presented for syncope. Following an extensive work up it was eventually elicited that this patient had an unusual etiology of syncope, a 19 cm x 24 cm renal cyst that was compressing the inferior vena cava (IVC).

MED15::TFE3 fusion renal cell carcinoma with extensive cystic change: A clinicopathologic and molecular genetic study of 2 cases, with an emphasis on differential diagnosis.

OBJECTIVES: TFE3-rearranged renal cell carcinomas (RCCs) harbor gene fusions between TFE3 and 1 of many partner genes. MED15::TFE3 fusion RCC is rare, often cystic, and easily misdiagnosed. METHODS: This study aimed to characterize 2 cases of MED15::TFE3 fusion RCC with extensive cystic change using fluorescence in situ hybridization and targeted RNA sequencing. RESULTS: Both patients were young adult women aged 29 and 35 years. Radiologically, both presented with a cystic Bosniak category II renal lesion. The cysts measured 9.3 cm and 4.8 cm in greatest dimension. Both patients underwent cyst enucleation, and neither had tumor recurrence or metastasis at 26 and 6 months of follow-up, respectively. Microscopically, both tumors were entirely cystic, with thick, fibrous cystic walls lined by small clusters of cells with clear to eosinophilic cytoplasm and uniform, round nuclei with inconspicuous nucleoli. There were also small aggregations of similar clear cells within the cystic walls. Foci of basement membrane-like material depositions were noted in 1 case; calcifications were observed in both cases. Both cases demonstrated nuclear positivity for PAX8 and TFE3 and cytoplasmic staining for Melan-A; HMB45, CAIX, and CK7 were negative. Fluorescence in situ hybridization revealed that both tumors were positive for TFE3 rearrangements. RNA sequencing identified MED15::TFE3 gene fusions in both cases. CONCLUSIONS: The main differential diagnosis of MED15::TFE3 fusion RCC includes multilocular cystic renal neoplasm of low malignant potential and atypical renal cysts. Molecular confirmation of TFE3 fusion is essential for establishing the correct diagnosis.

Activation of farnesoid X receptor retards expansion of renal collecting duct cell-derived cysts via inhibition of CFTR-mediated Cl- secretion.

The transcription factor farnesoid X receptor (FXR) regulates energy metabolism. Specifically, FXR functions to regulate cystic fibrosis transmembrane conductance regulator (CFTR)-mediated Cl- secretion in intestinal epithelial cells. Therefore, this study aimed to investigate the role of FXR in CFTR-mediated Cl- secretion in renal tubular cells and to further elucidate its effects on renal cyst formation and growth. CFTR-mediated Cl- transport was evaluated via short-circuit current (ISC) measurements in Madin-Darby canine kidney (MDCK) cell monolayers and primary rat inner medullary collecting duct cells. The role of FXR in renal cyst formation and growth was determined by the MDCK cell-derived cyst model. Incubation with synthesized (GW4064) and endogenous (CDCA) FXR ligands reduced CFTR-mediated Cl- secretion in a concentration- and time-dependent manner. The inhibitory effect of FXR ligands was not due to the result of reduced cell viability and was attenuated by cotreatment with an FXR antagonist. FXR activation significantly decreased CFTR protein but not its mRNA. In addition, FXR activation inhibited CFTR-mediated Cl- secretion in primary renal collecting duct cells. FXR activation decreased ouabain-sensitive ISC without altering Na+-K+-ATPase mRNA and protein levels. Furthermore, FXR activation significantly reduced the number of cysts and renal cyst expansion. These inhibitory effects were correlated with a decrease in the expression of protein synthesis regulators mammalian target of rapamycin/S6 kinase. This study shows that FXR activation inhibits Cl- secretion in renal cells via inhibition of CFTR expression and retards renal cyst formation and growth. The discoveries point to a physiological role of FXR in the regulation of CFTR and a potential therapeutic application in polycystic kidney disease treatment.NEW & NOTEWORTHY The present study reveals that farnesoid X receptor (FXR) activation reduces microcyst formation and enlargement. This inhibitory effect of FXR activation is involved with decreased cell proliferation and cystic fibrosis transmembrane conductance regulator-mediated Cl- secretion in renal collecting duct cells. FXR might represent a novel target for the treatment of autosomal dominant polycystic kidney disease.

Diagnosis and Surgical Treatment of a Renal Cyst Causing Unilateral Lameness in a Golden Eagle (Aquila chrysaetos).

This report describes the diagnosis and treatment of a benign renal cyst in an adult, female golden eagle (Aquila chrysaetos) presented for unilateral leg lameness. A cyst at the cranial division of the left kidney was diagnosed by computed tomography and was suspected of compressing the lumbosacral nerve plexus, resulting in limb lameness. The renal cyst was incompletely excised because the cyst wall was closely adhered to the kidney parenchyma and local blood supply. Fluid analysis and surgical biopsy of the cyst and left kidney confirmed the diagnosis of a benign renal cyst. No evidence of an infectious, inflammatory, or neoplastic etiology was noted. Postoperatively, the eagle's lameness resolved and the bird was ultimately released following recovery. During treatment for the renal cyst, the eagle was concurrently found to have increased serum titers on elementary body agglutination for Chlamydia psittaci and a positive titer for Aspergillus species antibody testing. The bird was administered doxycycline, azithromycin, and voriconazole for treatment of these potential pathogens prior to release. Unfortunately, the eagle was found dead 86 days postrelease due to an unknown cause. To the authors' knowledge, this is the first report of a golden eagle with a benign solitary renal cyst causing unilateral lameness secondary to nerve compression that was resolved with surgical excision.

Ultrasound-guided paravertebral nerve block anesthesia for percutaneous endoscopic laser unroofing treatment of symptomatic simple renal cysts-An innovative ambulatory surgery mode.

Objective: This study was designed to evaluate the feasibility, efficacy, and safety of percutaneous ureteroscopy laser unroofing as an ambulatory surgery for symptomatic simple renal cysts under multilevel paravertebral nerve block anesthesia. Methods: From December 2015 to September 2017, 33 simple renal cyst patients who had surgical indications were enrolled. Under ultrasound guidance, the T10/T11, T11/T12, and T12/L1 paravertebral spaces were identified, and 7-10 mL 0.5% ropivacaine was injected at each segment. Then a puncture needle was placed inside the cyst cavity under ultrasonic monitoring. A guidewire was introduced followed by sequential dilation up to 28/30 Fr. The extra parenchymal portion of the cyst wall was dissociated and incised using a thulium laser, and a pathological examination was performed. Results: Sensory loss to pinprick from T8 to L1 and sensory loss to ice from T6 to L2 were observed in all patients. None of the patients complained of pain during surgery. No serious complications occurred perioperatively. After the surgery, all patients recovered their lower limb muscle strength quickly, got out of bed, resumed oral feeding, and left the hospital within 24 h of admission. The pathologic diagnosis of all cyst walls was a simple renal cyst. The mean follow-up was 35.8 months. At the end of follow-up, the cyst units were reduced in size by more than 50% compared to the preoperative size, and no patient experienced a recurrence. Conclusion: Multi-level paravertebral nerve block for percutaneous ureteroscopy laser unroofing as an ambulatory surgery mode is feasible, safe, and effective for the treatment of simple renal cysts in selected patients.

nnUNet for Automatic Kidney and Cyst Segmentation in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a genetic disorder that causes uncontrolled kidney cyst growth, leading to kidney volume enlargement and renal function loss over time. Total kidney volume (TKV) and cyst burdens have been used as prognostic imaging biomarkers for ADPKD. OBJECTIVE: This study aimed to evaluate nnUNet for automatic kidney and cyst segmentation in T2-weighted (T2W) MRI images of ADPKD patients. METHODS: 756 kidney images were retrieved from 95 patients in the Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) cohort (95 patients × 2 kidneys × 4 follow-up scans). The nnUNet model was trained, validated, and tested on 604, 76, and 76 images, respectively. In contrast, all images of each patient were exclusively assigned to either the training, validation, or test sets to minimize evaluation bias. The kidney and cyst regions defined using a semi-automatic method were employed as ground truth. The model performance was assessed using the Dice Similarity Coefficient (DSC), the intersection over union (IoU) score, and the Hausdorff distance (HD). RESULTS: The test DSC values were 0.96±0.01 (mean±SD) and 0.90±0.05 for kidney and cysts, respectively. Similarly, the IoU scores were 0.91± 0.09 and 0.81±0.06, and the HD values were 12.49±8.71 mm and 12.04±10.41 mm, respectively, for kidney and cyst segmentation. CONCLUSION: The nnUNet model is a reliable tool to automatically determine kidney and cyst volumes in T2W MRI images for ADPKD prognosis and therapy monitoring.

Multiple and large simple renal cysts are associated with glomerular filtration rate decline: a cross-sectional study of Chinese population.

BACKGROUND: Although simple renal cyst (SRC) is a kind of structural alterations of kidney with age, the relationship between SRC and renal function is still obscure. We investigated the relationship between SRC and renal function in Chinese population. METHODS: The medical records of 41,842 individuals who underwent physical examinations at the Health Check-up Center at our institution in 2018 were reviewed. According to whether with SRC, they were divided into no-SRC and SRC groups. SRCs were classified into subgroups based on number (< 2 vs. ≥ 2) and size (< 2 cm vs. ≥ 2 cm). Logistic regression was used to examine the relationship between SRC and estimated glomerular filtration rate (eGFR). RESULTS: Multinomial logistic regression analysis showed that the adjusted odds ratio (OR) for eGFR slight decline in subjects with SRC was 1.26(95% confidence interval (95% CI):1.17-1.35, p < 0.001), and the OR for eGFR severe decline was 1.35(95% CI: 1.16-1.56, p < 0.001) compared with no-SRC. The adjusted OR of SRC number ≥ 2 and ≥ 2 cm on the risk of eGFR severe decline was the highest (OR:1.68, 95% CI:1.25-2.23, p < 0.01) of four SRC subgroups. CONCLUSIONS: SRC is related to eGFR decline, especially when the person with one more SRCs and the size of SRC is more than 2 cm. SRC could be a warning sign for clinicians to judge the decline of renal function.

Three Dimensional (3D) Laparoscopic Nephron-sparing Treatment of a Huge Cystic Nephroma: A Case Report and Literature Review.

Background/Aim: Cystic nephroma (CN) is a very rare, benign, renal cystic lesion, which is characterized by a usually unilateral, multicystic kidney mass. In adults it is seen more frequently in females (1:8 male-to-female ratio). The peak incidence of CN is between 50 and 60 years of age. Median age at diagnosis is 55 years for females and 44 years for men and it is a rare entity in adults under 30 years of age. Case Report: We report the case of a 52-year-old female patient with chronic right-flank pain, who was treated at our hospital. A multiloculated 10×8.6 cm Bosniak IV renal cyst tumor was depicted on retroperitoneal computed tomography. After a three-dimensional laparoscopic partial nephrectomy, the histopathological specimen examination revealed: a multilocular cystic nephroma. Conclusion: CNs are rare benign tumors that should be included in the differential diagnosis when treating large multiloculated complex renal cysts.

Decline in measured glomerular filtration rate is associated with simple renal cyst in Chinese patients with type 2 diabetes.

AIMS/INTRODUCTION: Simple renal cysts (SRC) are associated with age, hypertension and hyperuricemia, which are risk factors of renal impairment. This study aimed to investigate the prevalence of SRC and its association with measured glomerular filtration rate (mGFR) in patients with type 2 diabetes mellitus in China. METHODS: A total of 3,552 patients with type 2 diabetes mellitus admitted to Shanghai Sixth People's Hospital from January 2012 to December 2016 were investigated. All participants were diagnosed as SRC by color Doppler, and all participants were measured for GFR by using dynamic renal scintigraphy with technetium-99m-diethylene triamine peta-acetic acid. RESULTS: The prevalence of SRC was 17.4% (619 cases). Participants with SRC had significantly lower mGFR values than those without SRC (86.16 ± 26.20 vs 94.88 ± 23.98 mL/min/1.73 m2 , P < 0.001). In 478 participants with unilateral renal cyst, the mGFR of the kidney affected by SRC was significantly lower than that of the unaffected kidney (43.32 ± 13.74 vs 44.18 ± 13.34 mL/min/1.73 m2 , P = 0.014). The participants were divided into four groups according to the quartiles of mGFR level (≥109.50, 93.80-109.49, 76.90-93.79 and <76.90 mL/min/1.73 m2 ). The prevalence of SRC gradually increased with decreasing mGFR level (12.9, 13.9, 16.6 and 27.8%, respectively; P trend <0.01). After adjusting for age, sex, duration of diabetes, hypertension and other potential confounders, the logistic regression showed that SRC was an independent risk factor for impaired GFR (<60 mL/min/1.73 m2 ; odds ratio 1.656; 95% confidence interval 1.451-1.890, P < 0.001). CONCLUSION: SRC is an independent risk factor for the decrease of mGFR in Chinese diabetes patients, and could affect the renal GFR measured by dynamic renal scintigraphy on the SRC side.

The prevalence and associated risk factors of detectable renal morphological abnormalities in acromegaly.

PURPOSE: The aim of this study was to investigate the prevalence of simple renal cysts (SRCs) and kidney stone disease (KSD) together with laboratory data in patients with acromegaly through comparisons with healthy subjects, and to examine the possible risk factors associated with these abnormalities in acromegaly. METHODS: This retrospective, single-center study included 125 acromegaly patients (46.4 ± 11.6 years, 68 females/57 males) and 114 age-sex matched healthy individuals (45.3 ± 12.4 years, 59 females/55 males). Demographic data, clinical history, biochemical and abdominal/urinary system ultrasonographic data of the patients were reviewed. RESULTS: The SRC prevalence (28.8% vs. 8.8%, p < 0.001) and the longitudinal and transverse lengths of kidneys (p < 0.05) were significantly higher in patients with acromegaly compared to the control group. The presence of acromegaly was determined to increase the risk of SRC formation 12.8-fold. The prevalence of KSD was similar in both the patient and control groups (15.2% vs. 7.9%, p = 0.08). Patients with acromegaly with renal cysts (n = 36) compared to the group without cysts (n = 89) were older, had a higher male gender frequency, a longer pre-diagnosis symptom duration, and a higher incidence of hypertension and diabetes mellitus at the time of diagnosis. The multivariate logistic regression analysis showed that only advanced age and male gender were associated risk factors for SRCs in acromegaly patients. CONCLUSION: The results of this study showed that acromegaly disease significantly increased the prevalence of SRCs and kidney length compared to the age-sex matched healthy population, while the prevalence of KSD was similar. Advanced age and male gender were seen to be independent risk factors for SRC formation in patients with acromegaly.

Advantages of retrograde intrarenal incision versus laparoscopic surgery in management of pararenal cysts: a single-center experience.

PURPOSE: Renal cysts are typically a benign condition, and parapelvic cysts are a type of renal cyst that occur adjacent to the renal pelvis or renal sinus. Parapelvic cysts can increase the risk for injury to adjacent organs or urine leakage during laparoscopic surgery. Flexible ureteroscopes with laser assistance were used to make internal incisions in cysts. Perioperative outcomes of this method were compared with those of laparoscopic surgery. METHODS: Eight-three patients, who underwent surgical treatment for renal cysts at the authors' medical center between January 2019 and June 2022, were evaluated. Two patients were excluded because they originally opted for RIRS but subsequently converted to laparoscopic surgery. Patients were divided into 2 groups based on surgery type: laparoscopic; and RIRS for internal incision. Outcomes in both groups were analyzed. RESULTS: Of the 81 patients analyzed, 60 [74% (group 1)] underwent laparoscopic surgery and 21 [26% (group 2)] underwent RIRS for internal incision. The median operative durations for groups 1 and 2 were 87 and 56 min, respectively (p < 0.001). Relative to RIRS, laparoscopic surgery resulted in greater postoperative painkiller use (laparoscopic surgery versus [vs.] RIRS, 43% vs. 19%; p = 0.047). The median length of hospital stay was 2 and 1 days, respectively (p < 0.001). CONCLUSIONS: RIRS demonstrated several advantages over laparoscopic surgery for the internal incision of parapelvic cysts, including shorter operative duration, shorter hospital stay, and less postoperative pain control. These findings may guide the selection of appropriate surgical approaches for patients with renal cysts.

Deep learning-based automated kidney and cyst segmentation of autosomal dominant polycystic kidney disease using single vs. multi-institutional data.

PURPOSE: This study aimed to investigate if a deep learning model trained with a single institution's data has comparable accuracy to that trained with multi-institutional data for segmenting kidney and cyst regions in magnetic resonance (MR) images of patients affected by autosomal dominant polycystic kidney disease (ADPKD). METHODS: We used TensorFlow with a Keras custom UNet on 2D slices of 756 MRI images of kidneys with ADPKD obtained from four institutions in the Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) study. The ground truth was determined via a manual plus global thresholding method. Five models were trained with 80 % of all institutional data (n = 604) and each institutional data (n = 232, 172, 148, or 52), respectively, and validated with 10 % and tested on an unseen 10 % of the data. The model's performance was evaluated using the Dice Similarity Coefficient (DSC). RESULTS: The DSCs by the model trained with all institutional data ranged from 0.92 to 0.95 for kidney image segmentation, only 1-2 % higher than those by the models trained with single institutional data (0.90-0.93).In cyst segmentation, however, the DSCs by the model trained with all institutional data ranged from 0.83 to 0.89, which were 2-20 % higher than those by the models trained with single institutional data (0.66-0.86). CONCLUSION: The UNet performance, when trained with a single institutional dataset, exhibited similar accuracy to the model trained on a multi-institutional dataset. Segmentation accuracy increases with models trained on larger sample sizes, especially in more complex cyst segmentation.

Pathological report and prognostic meaning of Bosniak IV cysts: results from a contemporary cohort.

Introduction: Surgery is the recommended treatment for Bosniak IV renal cysts. We performed a retrospective analysis of Bosniak IV lesions surgically removed to increase evidence on their prognostic meaning. Material and methods: Patients with a Bosniak IV cyst were considered. A contrast-enhanced computed tomography (CT) scan or magnetic resonance imaging (MRI) detected a solid component with contrast enhancement. In no case a percutaneous biopsy was performed. A radical (9, 21.4%) or partial (33, 78.6%) nephrectomy was performed with laparoscopic (14, 33.3%) or robot-assisted (28, 66.7%) approach. Analysis of the final pathology was performed, and recurrence rate was assessed. Results: 42 patients were included. Median lesion size was 54.7 mm (IQR 20.0-81.2). A solid tumour was detected in 40 patients (95.2%), whereas in 2 cases (4.8%) a benign cyst without neoplastic component was diagnosed. Final pathology revealed a low-grade clear cell renal cell carcinoma (ccRCC) in 16 cases (38.0%), a multilocular cystic renal neoplasm of low malignant potential in 6 cases (14.3%), a low-grade papillary RCC (pRCC) type I in 4 cases (9.5%), a clear cell papillary RCC (ccpRCC) in 10 cases (23.8%) and an oncocytoma in 2 cases (4.8%). A high-grade ccRCC was detected in 2 cases (4.8%), whereas no patients had a pRCC type II. In all cases surgical margins were negative. Median follow-up was 24 months and no recurrence occurred. Conclusions: Our results increase evidence on the favourable pathology and good prognosis of Bosniak IV renal cysts, supporting the role of surgery as a definitive treatment and suggesting the need for a low-intensity follow-up.

A Unique Presentation of an Infected Renal Cyst: A Case Report and Literature Review.

Renal cysts are prevalent conditions and are often diagnosed incidentally. The infection of renal cysts is an uncommon presentation. It is even more rare in solitary simple cysts than in autosomal dominant polycystic kidney disease (ADPKD). Patients with infected renal cysts can have variable presenting symptoms; however, almost universally, they have flank pain. Here, we report a case of a solitary renal cyst infection in the absence of flank pain, a relatively rare condition. A 60-year-old male patient presented to our emergency department (ED) for ongoing periumbilical/lower abdominal pain, chills, and high-grade fever. He was initially seen in urgent care and thought to have a urinary tract infection (UTI). He was discharged on trimethoprim-sulfamethoxazole (TMP-SMX). He was hemodynamically stable in the ED and did not have flank pain. Urine culture showed Escherichia coli. Computed tomography (CT) showed changes concerning for possible early pyelonephritis of the right kidney area and an enlarged right upper pole renal cyst compared to previous imaging. The urology team was consulted, and the enlarging cyst was considered secondary to hemorrhage. The patient continued to have high-grade fevers and worsening abdominal pain during his stay despite being on culture-directed intravenous antibiotics. Consequently, the cyst was aspirated, and cultures grew E. coli with a similar antimicrobial susceptibility pattern as the one found in the urine. After the procedure, the fever and abdominal pain significantly improved. This case report describes a patient with an infected solitary renal cyst with a unique presentation. Imaging modalities can be misleading and delay the diagnosis. Appropriate source control via cyst aspiration and/or drain insertion is crucial for successful treatment.

Ouabain enhances renal cyst growth in a slowly progressive mouse model of autosomal dominant polycystic kidney disease.

Renal cyst progression in autosomal dominant polycystic kidney disease (ADPKD) is highly dependent on agents circulating in blood. We have previously shown, using different in vitro models, that one of these agents is the hormone ouabain. By binding to Na+-K+-ATPase (NKA), ouabain triggers a cascade of signal transduction events that enhance ADPKD cyst progression by stimulating cell proliferation, fluid secretion, and dedifferentiation of the renal tubular epithelial cells. Here, we determined the effects of ouabain in vivo. We show that daily administration of ouabain to Pkd1RC/RC ADPKD mice for 1-5 mo, at physiological levels, augmented kidney cyst area and number compared with saline-injected controls. Also, ouabain favored renal fibrosis; however, renal function was not significantly altered as determined by blood urea nitrogen levels. Ouabain did not have a sex preferential effect, with male and female mice being affected equally. By contrast, ouabain had no significant effect on wild-type mice. In addition, the actions of ouabain on Pkd1RC/RC mice were exacerbated when another mutation that increased the affinity of NKA for ouabain was introduced to the mice (Pkd1RC/RCNKAα1OS/OS mice). Altogether, this work highlights the role of ouabain as a procystogenic factor in the development of ADPKD in vivo, that the ouabain affinity site on NKA is critical for this effect, and that circulating ouabain is an epigenetic factor that worsens the ADPKD phenotype.NEW & NOTEWORTHY This work shows that the hormone ouabain enhances the progression of autosomal dominant polycystic kidney disease (ADPKD) in vivo. Ouabain augments the size and number of renal cysts, the kidney weight to body weight ratio, and kidney fibrosis in an ADPKD mouse model. The Na+-K+-ATPase affinity for ouabain plays a critical role in these effects. In addition, these outcomes are independent of the sex of the mice.

[Effect of a simple kidney cyst on renal function].

INTRODUCTION: Renal cysts are a common disease that occurs at a rate of 7-10%. Currently there are no clinical recommendations for the treatment of patients with simple renal cysts. In the current literature there is some evidence that a simple renal cyst has negative effects on renal function. Decreased renal function occurs due to partial atrophy and loss of the renal parenchyma (in the "crater" area at the base of the cyst) caused by compression. Therefore, the efforts to analyze the effect of simple kidney cysts on kidney function and identify the characteristics of the cyst that affect renal function to determine the indications for surgical treatment remains a substantial task. The aim of the study was to analyze the effect of simple renal cysts on renal function, to investigate the relationship between cyst size, atrophied parenchyma volume, and renal function, and to determine indications for surgical treatment of simple renal cysts. MATERIALS AND METHODS: We conducted a prospective cohort study. The study included 109 patients with simple renal cysts. Patients with a solitary cyst of the right or left renal kidney, grade I-II according to Bosniak classification, were included in the study. The estimated glomerular filtration rate (eGFR) of the patients was calculated using various formulas. A contrast CT scan of the urinary tract was also performed to determine the maximum size of the cyst, calculate the volume of the renal parenchyma, and the volume of the lost (atrophied) parenchyma. Patients underwent renal scintigraphy with calculation of total GFR and split renal function. We analyzed the symmetry of the function of both kidneys by comparing the GFR of the affected and healthy kidneys, analyzed the relationship between the presence of a kidney cyst and a decrease in GFR, between the maximum size of a renal cyst and a decrease in its function compared with that of a healthy kidney. We also analyzed the correspondence of total GFR values obtained in renal scintigraphy and GFR values calculated according to the formulas. RESULTS: Data from 109 patients were available for analysis; the mean blood creatinine was 87.4 mol/L. The median maximum cyst size was 80 mm. The median baseline volume of the affected kidney parenchyma was 174 ml, the median volume of the lost parenchyma was 49 ml, and the median proportion of the lost parenchyma was 28%. The median total GFR was 77.07 ml/min. The median GFR of the healthy kidney was 45.49 mL/min, and the median GFR of the kidney affected by the cyst was 34.46 mL/min. The median difference in GFR of the healthy and affected kidney units was 11 mL/min and was statistically significant. Comparison of the eGFR values obtained by the formulas with the reference values of GFR obtained by scintigraphy showed that the Cockcroft-Gault formula with standardization on the body surface area calculated closest eGFR values to the reference ones. Correlation analysis revealed a statistically significant association between the proportion of lost parenchyma volume and the maximum cyst size: =0.37 with 95% CI [0.20; 0.52] (p-value = 0). A multivariate logistic regression model revealed that a statistically significant factor influencing the probability of a significant decrease in GFR was the percent of lost renal parenchyma volume (OR=1,13; =0). CONCLUSIONS: Our study showed that growth of renal cysts associated with renal parenchyma atrophy and decrease of GFR of the affected kidney. An increase in the volume of atrophied parenchyma leads to the decrease in GFR of the affected kidney. The obtained data suggest that performing dynamic renal scintigraphy to assess the decrease in affected renal function and determine the indications for surgical treatment of renal cysts is a reasonable recommendation. According to the results of the study, the loss of 20% of the renal parenchyma can be considered an indication for renal scintigraphy. The Cockcroft-Gault formula with standardization on the body surface area allows to calculate closest GFR values to those obtained by scintigraphy and, therefore, can be recommended as the optimal formula for calculating eGFR in daily clinical practice.

Ultrasound-guided percutaneous intracystic deroofing is effective in the treatment of simple renal cysts.

OBJECTIVE: To investigate the efficacy and safety of ultrasound-guided percutaneous intracystic deroofing for the treatment of simple renal cysts. METHODS: A retrospective study was conducted to analyze the clinical data of 46 patients with dorsal exophytic simple renal cysts treated at the First Affiliated Hospital of Nanchang University between February 2017 and June 2022. The patients were divided into two groups according to the surgical method, with 20 cases undergoing ultrasound-guided percutaneous intracystic deroofing being assigned to the observation group and 26 cases treated by retroperitoneal laparoscopic renal cyst removal included in the control group. The operation time, blood loss, postoperative catheterization time, postoperative drainage tube indwelling time, postoperative hospital stay, and complications were compared. RESULTS: None of the 46 patients converted to open surgery. The observation group showed significantly less blood loss, shorter operation time, drainage tube drainage time, postoperative hospital stay, and indwelling catheter time than the control group (all P<0.05). The two procedures had a success rate of 100%. There were no statistical significances in K+, Na+, or serum creatinine between the two groups (all P>0.05). All patients were followed up (3 to 6 months) after surgery, and no cyst recurrence was found by imaging examination. CONCLUSIONS: Ultrasound-guided percutaneous intracystic deroofing of renal cysts is worthy of clinical application in the treatment of simple renal cysts due to its significant advantages such as short operation time, less trauma, quick recovery, safety, effectiveness, and low cost.