Infected calyceal diverticulum in pregnancy: A rare case.

A calyceal diverticulum is a transitional epithelium-lined outpouching of a renal calyx which communicates with the main collecting system through a narrow infundibulum. There are two types of calyceal diverticula: type I, the most common, communicates with the minor calyx, and type II communicates with the major calyx or renal pelvis. Calyceal diverticula are rare and mostly found incidentally; however, they can cause urinary tract infection symptoms (e.g., hematuria, pain, and fever). Diagnosing an infected calyceal diverticulum during pregnancy is particularly challenging due to overlapping symptoms and the limitations of imaging modalities that avoid ionizing radiation. Prompt diagnosis and treatment are necessary to avoid irreversible renal dysfunction and/or urological surgery. Currently, there are no established treatment guidelines for diagnosing and managing infected calyceal diverticula in pregnant patients. The rarity of this condition and the complexities introduced by pregnancy create challenges in standardizing care and determining the optimal treatment strategy, timing of interventions, and the impact on maternal and fetal outcomes. A 29-year-old primigravid woman presented emergently to the hospital at 15 weeks and 4 days gestation with concerns of severe right-sided flank pain and hematuria. Initial renal ultrasound revealed a complex, hypovascular lesion in the interpolar region of the right kidney measuring 6.9 × 6.8 × 3.7 cm, suspicious for mass versus pyelonephritis with associated phlegmon. Further characterization of the lesion by MRI revealed communication between the lesion and the mid-pole collecting system. Differential diagnoses included infected calyceal diverticulum, hydronephrosis of a duplicated system, renal abscess, and infected urinoma. Through a multidisciplinary approach, including ultrasound-guided placement of a drainage catheter at 16 weeks gestation, and tailored intravenous antibiotic therapy, the patient delivered a 3379 g male at 40 weeks and 0 days gestation. This case highlights the potential for conservative management in the absence of clear guidelines and underscores the importance of collaboration among obstetrics, urology, infectious disease, and interventional radiology teams. The implications of this case extend to increasing awareness of calyceal diverticula as a differential diagnosis in pregnant patients presenting with atypical urinary symptoms. It emphasizes the necessity of a multidisciplinary approach to ensure both maternal and fetal safety and offers valuable insights that could inform future cases, contributing to the development of more concrete guidelines for managing infected calyceal diverticula during pregnancy. Consent was obtained from the patient and IRB approval was not required for this case.

An Interesting Image of Carcinoma Breast with Renal Calyceal Diverticulum Mimicking Renal Metastasis on [18F]FDG PET/CT Scan.

A diverticulum is an outpouching of a hollow (or fluid-filled) structure in the body. They are most commonly seen in the urinary bladder, intestine, and pharyngeal region and are rarely seen in renal calyces. They are usually benign, asymptomatic, and are coincidentally detected. Due to their nonspecific clinical and radiological picture, sometimes they mimic malignant tumors, leading to misdiagnosis and treatment. We are presenting a case of 60-year-old female with right breast carcinoma, on whole body 18-fluorodeoxyglucose positron emission tomography-computed tomography; we observed an interesting finding in the right renal region mimicking renal metastasis.

PCNL vs RIRS in management of stones in calyceal diverticulum: outcomes from a global multicentre match paired study that reflects real world practice.

INTRODUCTION: Calyceal diverticulum (CD) is the outpouching of a calyx into the renal parenchyma, connected by an infundibulum. Often associated with recurrent stones, common surgical options include percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS). We aim to present the real-world practises and outcomes comparing both approaches and the technical choices made. MATERIALS AND METHODS: Retrospective data including 313 patients from 11 countries were evaluated. One hundred and twenty-seven underwent mini-PCNL and one hundred and eighty-six underwent RIRS. Patient demographics, perioperative parameters, and outcomes were analysed using either T test or Mann-Whitney U test. Categorical data between groups were analysed using the Chi-squared test. Propensity score matching (PSM) was performed matching for baseline characteristics. Subgroup analyses for anomalous/malrotated kidneys and difficult diverticulum access were performed. RESULTS: After PSM, 123 patients in each arm were included, with similar outcomes for stone-free rate (SFR) and complications (p < 0.001). Hospitalisation was significantly longer in PCNL. Re-intervention rate for residual fragments (any fragment > 4 mm) was similar. RIRS was the preferred re-intervention for both groups. Intraoperative bleeding was significantly higher in PCNL (p < 0.032) but none required transfusion. Two patients with malrotated anatomy in RIRS group required transfusion. Lower pole presented most difficult access for both groups, and SFR was significantly higher in difficult CD accessed by RIRS (p < 0.031). Laser infundibulotomy was preferred for improving diverticular access in both. Fulguration post-intervention was not practised. CONCLUSION: The crux lies in identification of the opening and safe access. Urologists may consider a step-up personalised approach with a view of endoscopic combined approach where required.

Calyceal diverticulum simulating a renal tumor.

Calyceal diverticulum (CD) is a rare anatomic anomaly with an incidence of 0.2% to 0.6% in the patients undergoing renal imaging. They are considered benign lesions and malignancy is exceedingly rare. For diagnosis it is suggested to perform a multiphasic contrast-enhanced computed tomography (CT) evidencing a diverticulum of the pelvicalyceal system with thin-walled cavities communicating with the central collecting system. However, they can be usually mistaken as kidney cancers leading to unjustified nephrectomy. Here, we present a case of a 34-year-old patient who underwent surgery in 2022 due to suspected kidney cancer and histopathological analysis surprisingly reported a CD.

Giant calyceal diverticulum with an extra-renal component: A case report.

Calyceal diverticula are urine-filled non-secretory cavities that result from outpouchings of the kidney's calyx or pelvis. These cavities lie in the renal parenchyma and are linked to the kidney's collecting system through a narrow channel. They are generally small in size and present without symptoms. Here, we report the case of a middle-aged patient who was diagnosed, following imaging exams, with a giant calyceal diverticulum presenting with an extra-renal component, a remarkably rare finding. The patient's condition was successfully treated through excision by laparoscopic surgery.

[Retrograde intrarenal surgery for kidney diseases].

INTRODUCTION: Retrograde intrarenal surgery (RIRS) is being actively implemented in the treatment of renal stones and other diseases. If necessary, RIRS can be combined with percutaneous procedures. AIM: To study the results of RIRS in patients with nephrolithiasis and various renal disorders. MATERIALS AND METHODS: A total of 106 patients who undergone RIRS were included in the study. There were 66 men (63.4%) and 40 women (36.6%). Mean age was 46.8+/-15.6 years. The indication for RIRS in 84 (79.2%) patients was renal stones. Calculus in calyceal diverticulum were diagnosed in 6 (5.7%), encrusted stents in 8 (7.7%), urinary fistulas after partial nephrectomy in 5 (4.7%), pelvis tumors in 2 (1.9%), pelvis perforation after marsupialization of parapelvic cyst in 1 (0.9%) patient, respectively. Simultaneous retro- and antegrade procedures were performed in 27 (25.5%) cases. In those with nephrolithiasis and encrusted stents, lithotripsy was done with the removal of stone fragments. Two patients underwent endoscopic resection of the pelvis tumor. In six patients, the neck of the diverticulum was incised after lithotripsy, while in five cases retrograde endoscopically controlled percutaneous treatment urinary fistulae was performed. In one case, laser fulguration of the pelvis defect with stenting was done. RESULTS: RIRS was effective in 72 (85.7%) of 84 patients with renal stones. The operation time was 70.8+/-10.2 minutes. In 12 (14.3%) cases with residual fragments, extracorporeal shock-wave lithotripsy (n=7) and repeated RIRS (n=5) were performed. The efficiency of RIRS after two sessions was 91.7%. Complications were observed in 11 (10.4%) patients. With encrusted stents, the operation time was 95.0+/-16.5 min. After laser fragmentation of encrustations in the lower part of the stent, percutaneous lithotripsy was performed with antegrade removal of its upper half. The time for RIRS in those with diverticula was 60.0+/-8.5 min, the average stone size was 8 mm (from 6 to 10 mm). In all cases lithotripsy with mucosal fulguration was successfully done. The procedures for urinary fistulae were also effective (operation time was 45.0 +/- 20.5 minutes) and there were no complications. CONCLUSION: RIRS is a safe and effective treatment for patients with nephrolithiasis and other kidney disorders. Modern flexible ureteroscopes allows to examine the collecting system and to perform lithotripsy and removal of stone fragments.

Prolonged postoperative urine leakage due to a calyceal diverticulum mimicking a renal cyst: A case report and literature review.

Background: The calyceal diverticulum is a rare cystic cavity that communicates with the collecting system via a narrow neck or infundibulum. In clinical practice, part of the calyceal diverticula is difficult to differentiate from simple renal cysts even after contrast-enhanced CT. To date, there have been few kinds of literature works on the diagnosis and treatment of calyceal diverticulum combined with renal pelvis dilatation, especially concerning the treatment of prolonged postoperative urine leakage. Case description: A 53-year-old woman with calyceal diverticulum and renal pelvis dilatation mimicking a simple renal cyst suffered urine leakage after receiving laparoscopic unroofing of the renal cyst. A persistent urine leakage was observed immediately after surgery, with about 200 ml of drainage fluid per day. We first attempted to place a double-J ureteral stent and indwell a catheter. After failing that, conservative treatment was performed. The core idea of the conservative treatment is retaining the drainage tube for more than 1 month, then clamping the drainage tube for 1 week, and finally removing the drainage tube. By 3 weeks of follow-up, the urine leakage disappeared, and the CT scan showed hydronephrosis of the right kidney without perirenal exudation and the lower pole cyst of the right kidney shrank significantly. Conclusion: This case, we reported here, is to attract the attention of clinicians. Renal cysts should exclude the possibility of the calyceal diverticulum. If urine leakage is inevitable after surgical treatment, our conservative treatment strategy is also an alternative method.

The Clinical Efficacy of Percutaneous Nephrolithotomy and Flexible Ureteroscopic Lithotripsy in the Treatment of Calyceal Diverticulum Stones: A Meta-Analysis.

BACKGROUND: The clinical efficacy of percutaneous nephrolithotomy (PCNL) and flexible ureteroscopic lithotripsy (FURL) in the treatment of calyceal diverticulum stones (CDs) remains controversial. We performed a meta-analysis to assess the clinical efficacy of PCNL and FURL in the treatment of CDs. METHODS: We searched a number of relevant electronic databases including China National Knowledge Infrastructure (CNKI), MEDLINE, PubMed, Web of Science, EMBASE, and Cochrane Library until January 31, 2022. STATA 15.1 software was used to analyze all data for this article. The quality of these studies was assessed by the Newcastle-Ottawa Scale (ranged from 0 to 9 stars). RESULTS: Finally, we selected 11 high-quality studies in our meta-analysis,which containing 486 patients. Meta-analysis showed that PCNL had higher stone-free rate [OR=3.55, 95% CI: 2.07 -6.10, P = 0.000], symptom-free rate [OR=3.56, 95% CI: 1.51 -8.38, p= 0.004], while it was slightly inferior to the FURL in bleeding volume [SMD = 1.27, 95% CI: (0.67,1.87), P = 0.000], hospital stay [SMD =2.86, 95% CI: 1.75-3.97, P = 0.000] and complication rate [OR =1.92, 95% CI: 1.10-3.33, P = 0.021], and there was no significant difference in operative time [SMD = -0.011, 95% CI: (-0.41,0.39), P = 0.957]. CONCLUSION: PCNL is safe and effective in the treatment of CDs, which can be considered as the first choice for the clinical treatment of CDs.

Type 2 calyceal diverticulum with an unusual appearance in the lower pole of the kidney.

A 45-year-old woman presented to our clinic with intermittent left flank pain. The family physician referred her for renal cystic mass with a calcified appearance. The non-contrast spiral abdominal computed tomographic (CT) scan demonstrated the mass-like cystic lesion with a densely calcified lesion in the lower pole of the kidney. A detailed history revealed that she underwent shock wave lithotripsy (SWL) for the lower pole renal stone one year ago. After SWL, the stone fragments migrated to the dependent diverticulum region and produced the misleading appearance of a Bosniak type III lesion. Contrast-enhanced computed tomography (CT) scan was done for further evaluation, and finally, the diagnosis of the calyceal diverticulum was confirmed in the lower pole of the kidney. Calyceal diverticula are the outpouching of the pyelocalyceal system lined by non-secretory transitional epithelium. It is a rare condition that occurs in less than 0.5% of the population. Most patients are asymptomatic and have been discovered incidentally in routine imaging modalities. As most of the patients are asymptomatic, many do not need intervention. However, in some instances, patients present with flank pain, hematuria, urinary tract infection, and stone formation in the diverticulum. They are in the differential diagnosis of renal cystic lesions such as simple renal cyst, renal cortical abscess, and parapelvic cyst. In renal cystic lesion besides of simple renal cyst or renal cystic mass, we should keep the differential diagnosis of the calyceal diverticulum type 2, especially in patients that underwent SWL for renal stones; the fragmented residual stone may have migrated to this dilated region and produce the deceptive appearance of a Bosniak type III lesion.

The Clinical Efficacy of Percutaneous Nephrolithotomy and Flexible Ureteroscopic Lithotripsy in the Treatment of Calyceal Diverticulum Stones: A Meta-Analysis

Background: The clinical efficacy of percutaneous nephrolithotomy (PCNL) and flexible ureteroscopic lithotripsy (FURL) in the treatment of calyceal diverticulum stones (CDs) remains controversial. We performed a meta-analysis to assess the clinical efficacy of PCNL and FURL in the treatment of CDs. Methods: We searched a number of relevant electronic databases including China National Knowledge Infrastructure (CNKI), MEDLINE, PubMed, Web of Science, EMBASE, and Cochrane Library until January 31, 2022. STATA 15.1 software was used to analyze all data for this article. The quality of these studies was assessed by the Newcastle-Ottawa Scale (ranged from 0 to 9 stars). Results: Finally, we selected 11 high-quality studies in our meta-analysis,which containing 486 patients. Meta-analysis showed that PCNL had higher stone-free rate [OR=3.55, 95% CI: 2.07 -6.10, P = 0.000], symptom-free rate [OR=3.56, 95% CI: 1.51 -8.38, p= 0.004], while it was slightly inferior to the FURL in bleeding volume [SMD = 1.27, 95% CI: (0.67,1.87), P = 0.000], hospital stay [SMD =2.86, 95% CI: 1.75-3.97, P = 0.000] and complication rate [OR =1.92, 95% CI: 1.10-3.33, P = 0.021], and there was no significant difference in operative time [SMD = -0.011, 95% CI: (-0.41,0.39), P = 0.957]. Conclusion: PCNL is safe and effective in the treatment of CDs, which can be considered as the first choice for the clinical treatment of CDs (AU)

A case report of renal calyceal diverticulum with hypertension in children and review of literature.

BACKGROUND: Renal calyx diverticulum refers to a cystic lesion covered with the transitional epithelium in the renal parenchyma. Although there is no clear evidence that calyx diverticulum can cause hypertension, there exists a close association between the two, and there are few related reports. Herein, we reported the case of a child with renal calyx diverticulum complicated with hypertension and summarized the diagnosis and treatment. CASE PRESENTATION: Physical examination of the patient, an 11-year-old child, revealed a left renal cyst with hypertension (155/116 mmHg). There were no related symptoms. Routine urine and blood biochemical examinations showed no abnormalities. Imaging revealed left renal cyst compression causing the hypertension. She underwent renal cyst fluid aspiration and injection of a sclerosing agent into the capsule, but her blood pressure increased again 3 days postoperatively. Color Doppler ultrasonography showed that the size of the left renal cyst was the same as that preoperatively. To further confirm the diagnosis, cystoscopic retrograde ureteropyelography was performed to confirm the diagnosis of renal calyx diverticulum. Subsequently, renal calyceal diverticulum resection and calyx neck enlargement were performed. The operation went smoothly and the blood pressure returned to normal postoperatively. No abnormalities were noted at the 7-month postoperative follow-up. CONCLUSION: There exists an association between renal calyx diverticulum and hypertension. Therefore, hypertension can be considered a surgical indication for renal calyx diverticulum. Moreover, renal calyceal diverticulum in children can be easily misdiagnosed as a renal cyst. Therefore, it is important to be vigilant to prevent a series of complications, such as postoperative urine leakage, in such cases.

Calyceal Diverticula Disease: Diagnosis and Management Options in the Era of Non-Contrast CT Scan.

INTRODUCTION: Calyceal diverticula (CD) are traditionally diagnosed by contrast studies. However, non-contrast CT is the standard imaging modality for kidney stones. Therefore, we aimed to determine if the lack of contrast imaging affected outcomes of the management of symptomatic CD with stone. MATERIALS AND METHODS: This is a retrospective study of patients diagnosed with CD with intracalyceal stone from 2000 to 2017 analyzing demographics, clinical data, and success of different treatment options. The timing of CD diagnosis is correlated to the success of the first treatment. RESULTS: Forty-eight patients were found. CD was diagnosed prior to intervention in 20 (42%) cases and intraoperatively during flexible ureteroscopy in 17 (35%) and 11 (23%) cases were diagnosed after failed intervention, mainly ESWL. We found that the success rate of treatment was highly affected by the timing and modality of diagnosis. Preoperative diagnosis of CD was associated with 69% success rate of the first intervention. In contrast, there was a 0% success rate of first treatment if CD was not diagnosed with contrast imaging. Furthermore, univariate analysis showed no significant association between sociodemographics and clinical variables and success treatment (p > 0.05). CONCLUSIONS: The delay in diagnosing CD with stone contributes significantly to the success rate and the number of treatments.

Retrograde intrarenal surgery with holmium laser lithotripsy for the management of calyceal diverticular calculi / 中华泌尿外科杂志

Objective:To investigate the efficacy and safety of retrograde intrarenal surgery(RIRS) with holmium laser lithotripsy in the management of calyceal diverticular calculi.Methods:A retrospective analysis was performed on 56 patients with calyceal diverticular calculi admitted to Huashan Hospital of Fudan University from January 2017 to May 2020. The 56 cases included 25 males and 31 females. The average age was 37.4 (ranging 22-67) years. Calyceal diverticular stones were located in the upper pole of the kidney in 32 cases, middle pole in 16 case and lower pole in 8 cases, with 32 cases on the left side and 24 cases on the right side. Multiple stones occurred in 46 cases, and single stone in 10 cases. The mean diameter of stones was 11.5 (ranging 3.0-17.5)mm. All 56 patients had different degrees of lumbar pain and/or hematuria preoperatively. Among them, 17 patients received extracorporeal shock wave lithotripsy (ESWL) with failure. Moreover, 9 cases suffered with urinary infection. All 56 patients with calyceal diverticular calculi underwent retrograde flexible ureterorenoscopic Ho: YAG laser lithotripsy under general anesthesia. The flexible ureterorenoscope was advanced into the kidney through the ureteral access sheath, looking for the cervical orifice of calyceal diverticulum. After finding renal diverticulum, holmium laser was used to incise and expand the neck or weak part of the diverticulum. The diverticular calculi were fragmented into particles less than 3 mm. Larger fragments were removed through a nitinol stone basket one by one. A F6 D-J stent was indwelled. The intraoperative conditions, postoperative complication rate and stone free rate were statistically analyzed.Results:The calyceal diverticular calculi in all 56 patients were discovered, and the diverticulum orifice were identified in 48 patients(85.7%). 53 of them underwent calyceal diverticular calculi fragmentation successfully. Lithotripsy failed in 3 cases, as the calculi were incarcerated in the lower pole calyceal diverticulum with a long narrow neck and the limitation of flexure at the end of the flexible ureteroscope. Two of them underwent percutaneous nephrolithotomy instead due to the calculi located in the posterior calyx. In another one case, ESWL was performed as the calculi located in the anterior calyx. Of the 17 cases received unsuccessful ESWL, RIRS was successful in 16 cases (94.1%). The mean operative time was 68.1(ranging 37-105)min, and mean hospitalization was 1.8 (ranging 1-3)d. The complication rate was 15.1%(8/53). All of these complications were mild (Clavien Ⅰ-Ⅱ). No serious complications such as perforation of the renal pelvis and ureter or major bleeding were occurred. After mean postoperative follow-up of 6.3(ranging 3-12) months, the stone-free rate was 83.0% (44/53) after the first procedure. 7 cases with residual stones ≥4mm received a second procedure. Among them, 6 cases received flexible ureterorenoscopy and the other one received ESWL and external physical vibration lithecbole therapy. The stone-free rate and symptom remission rate was 92.5% (49/53) and 96.2% (51/53) respectively after the second procedure, and no recurrence of calyceal diverticular calculi was observed during the stage of fllow-up.Conclusions:RIRS with holmium laser lithotripsy in the treatment of calyceal diverticular calculi, using the body's natural cavities, is a minimally invasive, safe and efficient strategy with slight complications. RIRS with holmium laser lithotripsy is an optional treatment for calyceal diverticular calculi.

Giant Calyceal Diverticulum in a Child with Solitary Kidney: A Rare Experience.

Calyceal diverticuli are rare entities which are difficult to diagnose radiologically as they mimic various other pathology. Close follow up is essential even in asymptomatic individuals to prevent complications. The authors present a giant calyceal diverticulum in a solitary kidney in a child that was managed by open surgery.

A Case Report of Calyceal Diverticulum: Differential Diagnosis for Organ-Preserving Operations.

Calyceal diverticula and epidermal cysts are extremely rare kidney lesions with unknown etiology and pathogenesis. They have non-specific clinical and radiological picture. Despite the benign nature, sometimes these disorders mimic malignant tumors leading to unjustified nephrectomy. We present a clinical and morphological observation of a multicystic lesion in a 76-year-old patient's right kidney filled with keratinized masses and imitating a malignant solid tumor. The detailed gross, histological and immunohistochemical (desmin, cytokeratin 7, uroplakin and p63) analyses of the kidney tissue excluded the malignant nature of the lesion. The final differential diagnosis was between an epidermal cyst and calyceal diverticulum with pronounced squamous cell metaplasia of urothelium. The upper pole localization of the lesion, its connection with the pelvicalyceal system through the unobstructed isthmus, the presence of urothelial lining and smooth muscle cells in its wall let us diagnose a calyceal diverticulum type I. Knowledge of the key clinical and morphological features of epidermal cysts and diverticula of the pelvicalyceal system will help the practicing physicians suspect the benign nature of such lesions and perform organ-preserving operations.

Treatment of a high output nephrocutaneous urine leak following treatment of a giant calyceal diverticulum in a child.

Calyceal diverticula are non-secretory transitional-epithelium lined cavities that are connected to the collecting system through a small ostium. They are rarely seen in young children. Although most remain asymptomatic, the presence of stagnant urine can result in infection, stone formation and pain. Treatment may consist of percutaneous ablation or open surgical excision. Failure of the ostium to completely seal can result in a persistent leak. We present a case of a massive calyceal diverticulum in a child who developed a postsurgical nephrocutaneous fistula recalcitrant to conservative management that was successfully managed with injection of fibrin glue.

The left ureterocele and stone of calyceal diverticulum in the patient with bilateral incomplete duplex kidneys managed by flexible ureteroscopy: a case report and literature review.

BACKGROUND: Duplex kidneys are one of the most common renal congenital abnormalities, mostly asymptomatic and of no clinical significance. There are little reports about the left ureterocele and stone of calyceal diverticulum in patients with bilateral incomplete duplex kidneys managed by flexible ureteroscopy. CASE PRESENTATION: A 69-year-old Chinese woman was presented with left waist pain for 1 month. A preoperative computed tomography (CT) scan and intravenous pyelogram revealed the left ureterocele which located in the left ureterovesical junction, and stone of calyceal diverticulum which located in the upper kidney of left incomplete duplex kidneys. The ureterocele was confirmed in view of ureteroscopy and the holmium laser was used for the resection of ureterocele. It took us a lot of efforts to find out the stone because of diverticular neck stenosis. Fortunately, when diverticular neck stenosis was incised internally by holmium laser, the stone was discovered clearly and removed using the holmium laser and nitinol stone basket through flexible ureteroscopy. A double-J ureteral stent was inserted and remained in place for 1 month. The symptom disappeared postoperatively and no complications were developed during the placement of the stent. There were no stone residents observed on CT scan before removing the ureteral stent 1 month later. CONCLUSIONS: Flexible ureteroscopy with holmium laser is feasible to manage the ureterocele and calyceal diverticulum stones in patients with bilateral incomplete duplex kidneys in one operation.

Differentiation of simple renal parenchymal cyst and calyceal diverticulum.

BACKGROUND: Calyceal diverticulum is the cystic eventration of the upper urinary tract within the renal parenchyma, which gives the first impression of a simple renal cyst and therefore can easily be misdiagnosed. We conducted a study to assess the role of static-fluid magnetic resonance (MR) urography in the differentiation of renal parenchymal cysts and calyceal diverticulum in comparison with focused renal ultrasonography (US). METHODS: Focused renal US, static-fluid, and excretory MR urography studies of 45 children who were admitted to our pediatric nephrology department with a diagnosis of renal cyst were reviewed retrospectively. Excretory MR urography was accepted as gold standard for the diagnosis of calyceal diverticulum. Sensitivity and specificity of focused renal US and static fluid MR urography in the diagnosis of renal calyceal diverticulum were assessed. Interobserver agreement between three radiologists in the diagnosis of calyceal diverticulum on MRI was also evaluated. RESULTS: The study included 29 patients (13 boys and 16 girls) aged between 6-18 years (mean 11.5 ± 4.1). Five calyceal diverticula and 24 solitary renal parenchymal cysts were diagnosed. The sensitivity and the specificity of focused renal US were 40% and 100% in the diagnosis of calyceal diverticulum. The sensitivity and the specificity of static-fluid MR urography were 100% and 91.6%, respectively. The degree of interobserver agreement was excellent for the diagnosis of diverticulum for static-fluid MR urography (κ = 0.86, 95% CI: 0.71-1.00). CONCLUSIONS: Static-fluid MR urography can be successfully used in children for the differentiation of renal parenchymal cyst and calyceal diverticulum due to its high sensitivity and specificity, without exposing children to ionizing radiation or intravenous contrast agents.

[Giant stone complicating calyceal diverticulum]. / Calcul géant compliquant un diverticule caliciel.

Calyceal diverticulum is acystic cavity in the renal parenchyma, communicating with the collecting system via an infundibulum. In more than 40% of cases it is associated with a stone and in most cases appears as milk of calcium forming a fluid level or multiple small stones. We here report the case of an 82-year old patient with no previous history, presenting with mild and intermittent right flank pain lasting for 8 years. Clinical examination was normal. The patient first underwent X-ray of urinary tree without preparation showing a density of calcium projecting into the upper pole of the right kidney (A). The patient then underwent uroscanner showing giant stone measuring 28mm within a caliciel diverticulum of the upper pole directly communicating with the renal pelvis (B). No associated urinary tract infection or haematuria were detected. Given patient's age and that he was paucisymptomatic and uninfected, therapeutic abstention and monitoring were indicated. In accordance with the recommendations of the experts, only symptomatic intradiverticular stones must be treated. First, extracorporeal shockwave lithotripsy (ESWL) allows improvement to the symptoms in 1 patient out of 2 and no stone fragmentation in 1 patient out of 4. In second intention, flexible uretero-renoscopy should be performed. Percutaneous nephrolithotomy can be performed if the stone is located in the lower pole (rare). Finally, in case of failure, laparoscopic treatment or open surgery may be proposed.

Retrograde intrarenal surgery in atretic calyceal diverticular stone, a case report.

Renal calyceal diverticulum is congenital outpouchings of the renal calyx and communicate with the main collecting system via a narrow channel. Stones have reportedly been found in up to 50% of diverticulum. Surgical intervention is indicated for symptomatic stone. Stenotic infundibulum had been reported but seldom literature reported of calyceal diverticular atresia. Here we presented a case of atretic calyceal diverticular stone which successful managed by retrograde intrarenal surgery safely.