Renal Ultrasound Research Articles

Relationship between red blood cell membrane disorders and Doppler ultrasound indices of renal blood flow in patients with chronic kidney disease

the study aimed to investigate the relationship between red blood cell membrane disorders and Doppler ultrasound indices of renal blood flow in patients with chronic kidney disease (CKD) stages1-2.
 Methods. The complex clinical, laboratory and instrumental (color duplex Doppler scanning of renal parenchyma vessels) examination was conducted in 131 CKD stage 1-2 patients. Among them, there were 47 patients with pyelonephritis, 48 patients with diabetic nephropathy, and 36 patients with primary glomerulonephritis. Each patients’ group was divided into 2 subgroups: with and without arterial hypertension. Twenty healthy volunteers were also included for the study control.
 Results. A significant correlation between indices of the erythrocytes morphology and basic Doppler ultrasonography parameters of the kidney vessels circulation, namely a.interlobaris was demonstrated in CKD patients with arterial hypertension. The most significant changes were observed in diabetic patients.
 Conclusion. The results of our study indicated a high informative value of renal Doppler ultrasonography as a non-invasive technique to diagnose the CKD progression in patients with comorbid hypertension

The Role of Specific Diet on the Treatment of Pediatric Asymptomatic Microscopic Hematuria; a Before and After Study:

Background and Aim: Asymptomatic microscopic hematuria (AMH) in children has been known as a troublesome clinical condition which demands a patient to visit a physician. This study aimed to investigate the role of a specific diet on the amelioration of AMH in children. Methods: The current analysis was carried out in children ranging from 6 months to 14 years. This before and after research study was performed to evaluate the effects of certain diet on the treatment of pediatric AMH. Renal function tests, kidney ultrasonography and urinary assessments were performed and patients with AMH were enrolled in this query. Study group was ordered to consume a specific hypoallergenic diet. The number of urinary red blood cells was compared before and after diet. Data were analyzed using SPSS. A value of P < 0.05 was considered significant. Results: Our special diet was effective in the treatment of stable microscopic hematuria in 72% of study group. Statistically, after a special diet, there was a significant decrease in the number of red blood cells in urine test (P <0.001). Conclusion: Specific hypoallergenic diet was effective in treatment of AMH in children. Reducing urinary red blood cell counts has been linked to the effectiveness of diet in the management of stable microscopic hematuria.

The different elements of the Urinary Tract Dilation (UTD) Classification System and their capacity to predict findings on mercaptoacetyltriglycine (MAG3) diuretic renography

The UTD Classification System risk stratifies postnatal UTD into three groups: low risk (UTD P1), intermediate risk (UTD P2), and high risk (UTD P3). In the original consensus document, a functional scan is not recommended for UTD P1 and is left to the discretion of the clinician for UTD P2 and P3. This study aims to understand which patients with postnatal urinary tract dilation would benefit from a functional study. We investigated how different elements of the UTD classification system predict differential renal function (DRF) and diuretic half-life (T½) on MAG3 scan in infants undergoing evaluation for prenatally detected UTD. This is a multicenter retrospective chart review of infants 6 months of age or younger evaluated for prenatal UTD, correlating their first MAG3 scan and first postnatal renal ultrasound (RUS). Multivariable logistic regression was used to find UTD elements predictive of DRF<40% and/or T½>20min. A total of 517 patients met study criteria. Median age at time of RUS and MAG3 renal scan was 48 days (IGR 31-81) and 63 days (IQR 45-98), respectively. DRF<40% was found in 6% of kidneys with UTD P2 and 35% of kidneys with UTD P3. T½>20min was found in 31% of kidneys with UTD P2 and 79% of kidneys with UTD P3. An abnormal ureter (OR 2.7, 95% CI 1.2-6.0) and parenchymal thinning (OR 16, 95% CI 5.8-41.4) were significant at predicting DRF<40%. Parenchymal thinning (OR 3.0, 95% CI 1.5-6.1) also predicted T½>20min, as did each cm increase in the anterior-posterior renal pelvic diameter (APRPD) (OR 4.8, 95% CI 3.0-7.7). The UTD system discriminates well and correlates with the likelihood of finding adverse features on diuretic renography. Patients in the UTD P3 high-risk category had a significantly higher incidence of decreased differential renal function and delayed drainage than those in UTD P1 and P2. Of the individual components of the UTD Classification system, the presence of parenchymal thinning was the most important factor in predicting both decreased differential renal function and delayed drainage. Given the high incidence of poor function and delayed drainage seen in the UTD P3 group, we believe a functional study should be recommended in the evaluation of these patients. Our findings support leaving the performance of a functional study at the discretion of the physician for UTD P2.

Relationship of Renal Cortical Echogenicity in Renal Ultrasonography with Course of Disease in Children with Idiopathic Nephrotic Syndrome

Background It is important to find a predictor for the course of Idiopathic Nephrotic Syndrome for better planning of treatment. Renal cortical echogenicity in ultrasonography has been postulated as a marker for the course of renal disease. The present study aimed at evaluating the relationship between renal cortical echogenicity and the course of Idiopathic Nephrotic Syndrome in children. Materials and Methods: In this cross-sectional study, the samples were consisted of 42 patients under 17 years old with Idiopathic Nephrotic Syndrome, who was admitted to Imam Reza Hospital, Kermanshah city, Iran, during 2015–2016. The echogenicity of renal cortex and liver was compared using the sonography scanning, and divided into three grades; grade (0): echogenicity of the renal cortex less than that of the liver, grade (1): echogenicity of the renal cortex is equal to that of the liver, and grade (2): The renal cortical echogenicity is greater than that of the liver. Results: Twenty-five patients (59.5%) were male and 17 patients (40.5%) were female. Twenty-seven patients (64.2%) were steroid-responsive, 10 patients (23.8%) were steroid-dependent and five patients (11.9%) were steroid-resistant. There was no statistically significant relationship between genders and the steroid response (p=0.81), but there was astatistically significant relationship between the course of the disease and the renal cortical echogenicity (p=0.01). Conclusion The results showed a relationship between steroid response and the course of the disease with renal cortex echogenicity, which means that higher renal cortical echogenicity may be a predictor of a more complicated course in Idiopathic Nephrotic Syndrome. Moreover, the small sample size, especially in the steroid-resistant group, was a limitation in the present study.

37-Year-Old Woman With Bilateral Lower Extremity Edema, Proteinuria, and Microscopic Hematuria

37-Year-Old Woman With Bilateral Lower Extremity Edema, Proteinuria, and Microscopic Hematuria

Management of Bladder Bowel Dysfunction in Children by Pelvic Floor Interferential Electrical Stimulation and Muscle Exercises: A Randomized Clinical Trial

ObjectiveTo assess efficacy of combined pelvic floor interferential (IF) electrical stimulation and muscle exercises on bladder bowel dysfunction (BBD) in children. Materials and methodsA total of 34 children with BBD (6 boys, 28 girls; mean age 7.4 ± 2.2) were included in this study. Children were evaluated with kidney and bladder ultrasounds, uroflowmetry + electromyography (EMG), and a complete voiding and bowel habit diary before treatment. Exclusion criteria were neuropathic disease, anatomical defects, and mental retardation. Participants were randomly allocated into 2 treatment groups including group A (n = 17) who underwent IF electrical stimulation in addition to pelvic floor muscle (PFM) exercises and group B (n = 17) who received PFM exercises alone. All children were re-evaluated by kidney and bladder ultrasounds, uroflowmetry + EMG and a voiding and bowel habit diary at the end of treatment sessions and 6 months later. ResultsConstipation improved in 14 of 17(82%) and 8 of 17(47%) children in group A and B respectively at the end of treatment sessions (P = .03). Daytime incontinence improved in all children in group A and 2 of 8(25%) children in group B after the treatment (P = .007). Urinary tract infection improved in 8 of 10(80%) and 5 of 13(38.4%) children in group A and B respectively, 6 months after the treatment (P = .02). No significant difference was observed in uroflowmetry measures between 2 groups after the treatment. ConclusionCombination of IF electrical stimulation and PFM exercises is an effective and safe modality for treatment of BBD in children.

A simple, refined approach to diagnosing renovascular hypertension in children: A 10-year study.

Despite advances in non-invasive vascular imaging, detection of renal artery stenosis via catheter angiography is the criterion standard for the diagnosis of renovascular hypertension (RVH). However, because of lack of evidence, the utility of various blood tests and imaging modalities remains unclear. We retrospectively analyzed the utility of blood tests (plasma renin activity [PRA], aldosterone, and renal vein renin[RVR] values) and imaging studies (computed tomography angiography [CTA], kidney ultrasonography[US]) by comparing them with catheter angiography. Ten pediatric patients with RVH at two institutions from January 2008 to December 2017 were recruited. The sensitivities for diagnosing RVH via imaging and blood tests (kidney [US], PRA, and aldosterone) were derived by examining patient records. Furthermore, the sensitivity and specificity of CT angiography were calculated by considering both the affected and non-affected renal arteries of the patients. A high sensitivity for diagnosing RVH via kidney US(89%) and PRA (80%) was observed. The sensitivity and specificity of CTA were 100%, each. RVR sampling did not aid in the diagnosis of RVH; only two of six patients with unilateral RVH showed significant laterality of RVR boundary ratios. Renal scintigraphy facilitated detection of a non-functional kidney (split renal function <5%). RVH in children could be diagnosed utilizing non-invasive blood and imaging tests, without catheter angiography. We recommend kidney length measurement along with measurement of PRA level, as a simple and highly useful screening test, followed by CTA as a diagnostic test.

Value of Renal Vascular Doppler Sonography in Cardiorenal Syndrome Type 1.

Worsening of renal function in a patient with acute decompensated heart failure is called cardiorenal syndrome (CRS) type 1. Recent studies have shown an association of persistent systemic venous congestion with renal dysfunction. This trial was set up to investigate the changes of renal Doppler parameters with diuretic therapy in patients with CRS type 1. Cases of CRS type 1 were identified among patients hospitalized for decompensated heart failure. Serial measurements of the renal venous impedance index (VII) and arterial resistive index (ARI) were calculated by pulsed wave Doppler sonography. A total of 30 patients who had creatinine improvement with diuresis (group 1) and 34 patients without any improvement (group 2) were analyzed. Patients in group 1 had higher median VII and ARI (VII, 0.86 versus 0.66; P < .001; ARI, 0.78 versus 0.65; P < .001) on admission. A high ARI on admission (odds ratio, 6.25; 95% confidence interval, 1.84-14.3; P = .003) predicted the improvement of serum creatinine levels with diuretic therapy independent of confounding factors in patients with CRS type 1. Renal vascular Doppler parameters might offer guidance on the diagnostic and therapeutic strategies in prescribing decongestive therapy for decompensated heart failure.

Renal arteriography with endovascular ultrasound for the management of renal infarction patients

BackgroundRenal infarction (RI) is a rare disease with poor prognosis. Appropriate secondary prevention treatment is essential and requires an exhaustive etiological assessment. We aimed to determine whether invasive endovascular explorations may improve the diagnostic process and change the secondary prevention treatment strategy in RI patients.MethodsWe report a retrospective observational study of 25 RI patients referred to Tours University Hospital between 2011 and 2018 for etiological investigation including renal arteriography and intravascular ultrasonography (IVUS). We sought for antithrombotic treatment regimen, vital status, bleeding and ischemic outcomes during the median follow-up of 59 months.ResultsInvasive explorations showed local arterial disease in 14 patients (56%). This led to a diagnosis or change in diagnosis in 9 patients (36%) and to a change in antithrombotic strategy in 56% of cases, with an increased prescription of antiplatelet therapy. No patient died, only two patients (8%) had persistent mild renal insufficiency. One IVUS complication was reported and treated without any significant long-term consequences.ConclusionInvasive endovascular investigations of RI may modify the secondary prevention treatment through a better assessment of the aetiology of RI. Multicentric randomized studies are necessary to advocate the hypothesis that invasive exploration of renal artery can improve long-term prognosis.

Prognostic imaging biomarkers for diabetic kidney disease (iBEAt): study protocol

BackgroundDiabetic kidney disease (DKD) remains one of the leading causes of premature death in diabetes. DKD is classified on albuminuria and reduced kidney function (estimated glomerular filtration rate (eGFR)) but these have modest value for predicting future renal status. There is an unmet need for biomarkers that can be used in clinical settings which also improve prediction of renal decline on top of routinely available data, particularly in the early stages. The iBEAt study of the BEAt-DKD project aims to determine whether renal imaging biomarkers (magnetic resonance imaging (MRI) and ultrasound (US)) provide insight into the pathogenesis and heterogeneity of DKD (primary aim) and whether they have potential as prognostic biomarkers in DKD (secondary aim).MethodsiBEAt is a prospective multi-centre observational cohort study recruiting 500 patients with type 2 diabetes (T2D) and eGFR ≥30 ml/min/1.73m2. At baseline, blood and urine will be collected, clinical examinations will be performed, and medical history will be obtained. These assessments will be repeated annually for 3 years. At baseline each participant will also undergo quantitative renal MRI and US with central processing of MRI images. Biological samples will be stored in a central laboratory for biomarker and validation studies, and data in a central data depository. Data analysis will explore the potential associations between imaging biomarkers and renal function, and whether the imaging biomarkers improve the prediction of DKD progression. Ancillary substudies will: (1) validate imaging biomarkers against renal histopathology; (2) validate MRI based renal blood flow measurements against H2O15 positron-emission tomography (PET); (3) validate methods for (semi-)automated processing of renal MRI; (4) examine longitudinal changes in imaging biomarkers; (5) examine whether glycocalyx and microvascular measures are associated with imaging biomarkers and eGFR decline; (6) explore whether the findings in T2D can be extrapolated to type 1 diabetes.DiscussioniBEAt is the largest DKD imaging study to date and will provide valuable insights into the progression and heterogeneity of DKD. The results may contribute to a more personalised approach to DKD management in patients with T2D.Trial registrationClinicaltrials.gov (NCT03716401).

Resolution of Hydronephrosis in Children with Dysfunctional Voiding After Biofeedback Therapy: A Randomized Clinical Trial.

We assessed efficacy of biofeedback therapy and home pelvic floor muscle exercises in children with dysfunctional voiding (DV) associated with mild to moderate hydronephrosis. This prospective study comprised fifty seven children (21 boys, 36 girls; mean age 8.9 ± 2.6) with DV and mild to moderate hydronephrosis. Children were randomly allocated into two treatment groups including control group who underwent standard urotherapy and case group who received biofeedback therapy in addition to standard urotherapy. A 99mTc diethylenetriamine pentaacetic acid (99mDTPA) scan, voiding cystoureterography, kidney and bladder ultrasounds, voiding diary and uroflowmetry with electromyography (EMG) were performed in all study participants at the baseline. Children with evidence of complete obstruction in DTPA scan and vesicoureteral reflux were excluded from enrollment. A complete voiding diary, kidney and bladder ultrasounds and uroflowmetry/EMG were also performed 6months and 1year after completion of the treatment. We noted a more significant decline in anteroposterior pelvic diameter in case group compared to control group (P < 0.05). The mean maximal urine flow rate prior to treatment was 16.5 ± 2.6 and 16.1 ± 3ml/s in case and control groups, respectively. This finding increased significantly 1year after the treatment in case group compared to controls (25 ± 7.2ml/s vs. 18.4 ± 5.9ml/s, respectively; P < 0.001). Improvement of various parameters in voiding diary was also more significant in the case group. Biofeedback therapy can effectively resolve non-refluxing and non-obstructive hydronephrosis in children with DV.

Point-of-Care Ultrasound for Native Kidney Biopsies.

Percutaneous kidney biopsy is a key procedure in the diagnosis and management of kidney disease but is being performed by nephrologists with decreasing frequency (1). Although it is a required component of subspecialty training in nephrology, exposure of trainees is often minimal. This results in fewer faculty with this skill, thereby accelerating this decline. The underlying reasons are manifold but stem in part from unfamiliarity with ultrasonography and availability of equipment. Consequently, biopsies are increasingly being performed in radiology departments, often under computed tomography guidance that results in unnecessary radiation exposure and cost because ultrasound guidance is sufficient in most patients (2,3). When performed by nephrologists, the biopsy is usually guided by a sonographer or radiologist, which complicates scheduling and is an inefficient use of manpower. With point-of-care sonography now widely available and increasingly being taught during medical school and residency, guidance of biopsies should no longer be an obstacle for nephrologists. Comprehensive training in sonography has been a component of the nephrology program at this institution for the past 25 years and has included guidance of percutaneous kidney biopsies. Over two decades ago, we reported a small series showing favorable success and complication rates for biopsies guided and performed entirely by nephrology faculty and trainees (4). We now report our experience with a much larger series of biopsies performed over a 22-year period. ### Patients This was a retrospective study in which a database of all kidney ultrasounds performed by the nephrology service at Emory University Hospital was searched for native kidney biopsies from July 1996 to September 2018. In addition to sonographic data, this database also contains information on the success rates. Additional information, including complications, was obtained on all biopsies since 2008 through review of the medical records. The study was approved by the Institutional Review Board …

Point-of-care ultrasound is an accurate, time-saving, and cost-effective modality for post-operative imaging after pyeloplasty

Dismembered pyeloplasty is considered the gold standard treatment for ureteropelvic junction obstruction (UPJO). Although the frequency and timing of follow up imaging after pyeloplasty is variable, renal ultrasound (RUS) is commonly utilized. With minimal training, point-of-care ultrasound (POCUS) can be easily performed by a urologist during a post-operative visit. Our hypothesis is that POCUS is an accurate, time-saving, and cost-effective alternative to a complete retroperitoneal ultrasound (CRUS) performed by the Radiology Department after pyeloplasty. The clinical records of all children who underwent pyeloplasty (by any method) over a 12 month period at our institution were retrospectively reviewed. The exact timing and method (POCUS vs. CRUS) of follow up imaging was surgeon-dependent. Statistical analysis was performed to compare the time and cost of POCUS vs. CRUS. The clinical course of each patient who had each type of imaging was assessed. A total 45 patients were included in this analysis. Over a mean follow up period of 29 months, a total of 73 CRUS and 67 POCUS were performed. Each CRUS on average added 2h to each patient's healthcare encounter. Had the 73 CRUS been performed as POCUS instead, this would have corresponded to $83,751 less charges to payers. There was no difference in the rate of the detection of worsening, stable, or improved hydronephrosis (HN) between either modality (p>0.05). The recommended follow up time for observed HN was no different between CRUS and POCUS (p>0.05). Children with worsening HN on POCUS underwent functional studies without confirmatory CRUS. Interestingly, two patients had metachronous, contralateral UPJO discovered during post-operative imaging. These were both discovered by POCUS. Nineteen (42%) patients who had attended at least one post-operative visit were eventually loss to follow-up. This occurred exclusively in those who did not have worsening ultrasound (p<0.01). There was no difference in the loss to follow-up after POCUS (8) or CRUS (12) (p>0.05). POCUS performed by a urologist is an accurate assessment of HN after pyeloplasty with time and cost savings to compared to a CRUS performed by a radiologist. POCUS is not associated with any difference in rate of detection of worsening HN or rate of loss to follow up.

Severe ureteropelvic junction obstruction with massive hydronephrosis causing compression of the inferior vena cava

A 7-week-old girl presented with tachypnea and abdominal distension. Abdominal ultrasonography demonstrated a 16 cm cystic mass in the right abdomen. Contrast-enhanced T2-weighted magnetic resonance imaging revealed severe hydronephrosis of the right kidney with thinning of the renal parenchyma consistent with a massive ureteropelvic junction (UPJ) obstruction. A percutaneous nephrostomy tube was placed for decompression of her right kidney and 1270 ml of fluid was drained. The patient underwent an open pyeloplasty. Her follow-up renal ultrasonography demonstrated resolution of her severe hydronephrosis.

Laparoscopic totally intracorporeal ileal ureter replacement: a multi-institutional study

Objective To prove the feasibility, as well as the reproducibility of laparoscopic totally intracorporeal ileal ureter replacement (LIUR), by presenting a multicenter patient cohort with a long follow-up. Material and methods Records of patients undergoing different types of ureteral replacements have been collected. Follow-up included a chemical profile and urine cultures. Imaging consisted of renal ultrasonography and excretory urography, as well as a cystography or an isotopic renography when indicated. Results Forty patients were included in the study. Twelve underwent a right, 20 a left, and eight a bilateral laparoscopic ureteral replacement. The mean procedure time was 335 (150–680) minutes and the mean estimated blood loss was 221 (50–400) mL. Only three patients presented intraoperative complications, which were managed immediately, and three patients presented a Clavien III postoperative complication. Abdominal drains and nephrostomy tubes were removed after 24–36 h and 7–10 days, respectively. The mean hospital stay was 13.5 (10–35) days. Follow-up was at least six months. Conclusions LIUR constitutes a feasible and reproducible method for the restoration of long ureteral defects.

Technical considerations in retroperitoneoscopic pyeloplasty in children: an early experience

Retroperitoneoscopic pyeloplasty is considered as one of the acceptable approaches for pelviureteric junction obstruction (PUJO) in children. Some consider it better than the open and laparoscopic approaches; but it has its own technical challenges. To analyse technical aspects in the initial learning curve of retroperitoneoscopic pyeloplasty for pelviureteric junction obstruction (PUJO) in children and to discuss certain tips and tricks. We retrospectively evaluated the data of consecutive 10 pelviureteric junction obstruction cases undergone retroperitoneal pyeloplasty in 2 years duration (January 2016 to December 2017). All patients had undergone ultrasound kidney ureter bladder (KUB), intravenous pyelography (IVP) and Ethylene dicysteine (EC) scan. A single surgeon operated on all the patients and placed a DJ stent intraoperatively. Postoperatively, the patients underwent an EC scan and IVP at 6 months. The patient records and operative videos were assessed. The average patient age was 8.4 ± 2.31 years (5–11 years). Intraoperatively, two patients had crossing vessels and the rest 8 had intraluminal narrowing. The mean operating time was 207.5 ± 36.15 min (150–285 min) and mean hospital stay was 3 ± 1.49 days (2–7 days). The postoperative course was uneventful in almost all except one who developed perinephric collection and had to undergo pigtail drainage. On follow up, all patients showed improved drainage at the PUJ except one. Retroperitoneoscopic pyeloplasty for pelviureteric junction obstruction can be optimally practiced by understanding the technical difficulties associated with it and the corresponding tips to ease the procedure. The advantages of going retroperitoneoscopically can be achieved and utilised in full for the benefit of the patient.

Accuracy of ultrasound in the diagnosis of classic metaphyseal lesions using radiographs as the gold standard.

Diagnosis of classic metaphyseal lesions (CMLs) in children suspected for child abuse can be challenging. Ultrasound (US) can potentially help diagnose CMLs. However, its accuracy is unknown. To evaluate the accuracy of US in the diagnosis of CMLs using skeletal survey reports as the gold standard. US of the metaphysis was performed in three patient groups age <1year. Informed consent was obtained for patients scheduled for renal US (Group 1) and for patients scheduled for skeletal surveys for possible child abuse (Group 2). Targeted US was also performed in selected patients to evaluate for possible CML suspected on radiographs (Group 3). In Groups 1 and 2, US was performed of both distal femurs, and of either the right or left proximal and distal tibia. Two radiologists (Rad1 and Rad2) independently reviewed the US studies, blinded to history and other imaging. US sensitivity and specificity were calculated using the following gold standards: CML definitely seen on skeletal survey (positive), CML definitely not seen on skeletal survey or part of renal US group (negative). Cases where the skeletal survey was indeterminate for CML were excluded. Kappa statistics were used to evaluate interobserver variability. Two hundred forty-one metaphyseal sites were evaluated by US in 63 children (mean age: 5months; 33 males); 34 had skeletal surveys and 29 had renal US. Kappa for the presence of CML was 0.70 with 95.7% agreement. US sensitivity was 55.0% and 63.2% and the specificity was 97.7% and 96.7% for Rad1 and Rad2, respectively. US has low sensitivity and high specificity in CML diagnosis. Thus, negative US does not exclude CML, but when the radiographs are equivocal, positive US can help substantiate the diagnosis.

Clinical characteristics of familial hypocalciuric hypercalcaemia type 1: A multicentre study of 77 adult patients.

Familial hypocalciuric hypercalcaemia type 1 (FHH1), related to heterozygous loss-of-function mutations of the calcium-sensing receptor gene, is the main differential diagnosis for primary hyperparathyroidism. The aim of our study was to describe clinical characteristics of adult patients living in France with a genetically confirmed FHH1. This observational, retrospective, multicentre study included 77 adults, followed up in 32 clinical departments in France, with a genetic FHH1 diagnosis between 2001 and 2012. Hypercalcaemia was diagnosed at a median age of 53years [IQR: 38-61]. The diagnosis was made after clinical manifestations, routine analysis or familial screening in 56, 34 and 10% of cases, respectively, (n=58; data not available for 19 patients). Chondrocalcinosis was present in 11/51 patients (22%), bone fractures in 8/56 (14%) and renal colic in 6/55 (11%). The median serum calcium was 2.74mmol/L [IQR: 2.63-2.86mmol/L], the median plasma parathyroid hormone level was 4.9pmol/L [3.1-7.1], and the median 24-hour urinary calcium excretion was 2.8mmol/24hours [IQR: 1.9-4.0]. Osteoporosis (dual X-ray absorptiometry) or kidney stones (renal ultrasonography) were found in 6/38 patients (16%) and 9/32 patients (28%), respectively. Fourteen patients (18%) underwent parathyroid surgery; parathyroid adenoma was found in three patients (21%) and parathyroid hyperplasia in nine patients (64%). No correlation between genotype and phenotype was established. This large cohort study demonstrates that FHH1 clinical characteristics can be atypical in 33 patients (43%). Clinicians should be aware of this rare differential diagnosis in order to adopt an appropriate treatment strategy.

Botulinum Toxin Type A Therapy: Intravesical Injection or Electromotive Drug Administration

To compare the outcomes of intravesical injection of botulinum toxin A (BoNTA) with intravesical electromotive drug administration (EMDA) of BoNTA on urinary incontinence secondary to neuropathic detrusor overactivity (NDO) in children with myelomeningocele (MMC). A total of 26 children with MMC (11 boys, 15 girls) who had urinary incontinence secondary to NDO were retrospectively enrolled in the study. Patients in EMDA group (n = 14), using an electrode-catheter, 10 IU/kg of BoNTA were inserted into the bladder for EMDA without anesthesia and on an outpatient basis. The EMDA equipment was connected to the electrode of indwelling catheter and 2 dispersive electrodes, a pulsed current generator delivered 10-20 mA for 20 minutes. Patients in injection group (n = 12) were received interavesical injection of 10 IU/kg of BoNTA via rigid cystoscope on an inpatient basis. All patients had been evaluated by a voiding diary, urodynamic study, renal, and bladder ultrasounds before, 6 months and 1 year after the treatment. Six months after the treatment, 12 of 14 (85.7 %) and 8 of 12 (66.6%) patients in EMDA and injection groups respectively became completely dry between 2 consecutive clean intermittent catheterizations, which maintained in 11 of 14 (78.5%) of patients in EMDA group compared to 6 of 12 (50%) of patients in injection group, 1 year after the treatment. Patients in both groups improved after the treatment; however improvement in EMDA group was more prominent with better sustained effects. BoNTA/EMDA is a feasible, reproducible, cost benefit, and pain free method as an outpatient basis and no need for anesthesia.

SUN-LB13 Idiopathic Infantile Hypercalcemia Secondary to CYP24A1 Mutation: A Rare Case Without Exogenous Vitamin D Supplementation

Background: Mutations in CYP24A1, which encodes 24-hydroxylase, the key enzyme for Vitamin D breakdown, cause symptomatic hypercalcemia and nephrocalcinosis in infants on Vitamin D supplementation. New, symptomatic diagnoses of idiopathic infantile hypercalcemia without exogenous supplementation are rare. Previous case reports describe a seasonal effect with worsening hypercalcemia and hypercalciuria during summertime, attributed to increased sun exposure and endogenous Vitamin D production. Clinical Case: A 10-month-old female presented to endocrine care with hypercalcemia and nephrocalcinosis, detected on renal ultrasound (US) due to history of UTI. Her first renal US and serum calcium (Ca) at 3mo of age were normal. Subsequent renal US at 6mo and 9mo of age demonstrated nephrocalcinosis, prompting nephrology and endocrine evaluation. History was significant for failure to thrive. She was born in the fall, with worsening hypercalcemia and nephrocalcinosis during the summer. Diet consisted of standard infant formula and age appropriate solid foods with no added Vitamin D supplementation (~300 IU/day in her formula). She had no family history of nephrocalcinosis, nephrolithiasis, bone disease, or disorders of Ca regulation. Initial labs were notable for Ca corrected for albumin 11.5 (7.8-11.1 mg/dL), PTH <4 (8.7-77.1 pg/mL), 25-OH-Vitamin D 81 (30-96 ng/mL), 1,25-OH-Vitamin D 23.1 (26.1-95 pg/mL), Urine Ca/creatinine ratio of 0.9 mg/mg (<0.81), normal chromosomal microarray, and normal thyroid function tests. She was started on reduced mineral formula PM 60/40. One week later, repeat Ca level increased to Ca corrected 14.2 (7.8-11.1 mg/dL). She was admitted for IV fluids and pamidronate, and was transitioned to a low Ca and Vitamin D formula (Calcilo), with improvement in Ca levels. Testing revealed an increased ratio of 25-OH-Vitamin D to 24,25-OH-Vitamin D of 192 (normal <25), and genetic testing showed 2 pathogenic missense mutations in CYP24A1 genes: c.1226T>C p.(Leu409Ser) and c.1186C>T p.(Arg396Trp). The Leu409Ser mutation has shown a small amount of 24-hydroxylase activity in previous in vitro analysis. She has continued a low Ca diet with stable Ca corrected of 10.7-10.8 (8.7-9.8 mg/dL) and significantly improved weight gain. Conclusion: This is one of the few documented cases of symptomatic idiopathic infantile hypercalcemia secondary to CYP24A1 mutation in an infant without exogeneous Vitamin D supplementation. Her nephrocalcinosis and hypercalcemia worsened over the summer, suggesting increased sun exposure may have been a contributing factor. This case demonstrates that 1,25-OH-Vitamin D levels may be normal or low in this condition, particularly for individuals with the Leu409Ser mutation who may retain partial 24-hydroxylase function.