Renal scintigraphy as an early and efficient method for detecting loss of renal function in a cat

Case summary A 6-year-old mixed-breed male cat was evaluated for a routine annual health assessment. No alterations on physical examination were observed other than mild pain on palpation of the right kidney. Complete blood count, serum biochemistry (including symmetric dimethylarginine), urinalysis and urine protein:creatinine ratio were within the reference intervals for the species. Abdominal ultrasonography showed the presence of asymmetric kidneys, decreased corticomedullary definition, presence of a cyst on the left kidney and moderate renal pelvis dilatation on the right kidney. Dynamic renal scintigraphy (technetium [99mTc]-diethylenetriamine pentaacetic acid) revealed a single functioning kidney on the left. Static renal scintigraphy (99mTc-dimercaptosuccinic acid) exhibited renal activity practically restricted to the left kidney (relative uptake was 99% for the left kidney and 1% for the right kidney). Results of renal scintigraphy showed that the left kidney was compensating for the lack of function of the right one. GFR was 2.17 ml/min/kg, which is considered subclinical renal insufficiency and is in accordance with the case, as the cat was asymptomatic and did not present alterations in laboratory parameters. Relevance and novel information Renal scintigraphy was an important tool to determine the loss of renal function in one of the kidneys and mild reduction of global GFR. In this case report, renal scintigraphy proved to be more sensitive in the assessment of renal function than other tests routinely performed.

MR-Proadrenomedullin as biomarker of renal damage in urinary tract infection in children

Background Midregional-proadrenomedullin (MR-proADM) is a useful prognostic peptide in severe infectious pathologies in the adult population. However, there are no studies that analyze its utility in febrile urinary tract infection (fUTI) in children. An accurate biomarker would provide an early detection of patients with kidney damage, avoiding other invasive tests like renal scintigraphy scans. Our objective is to study the usefulness of MR-proADM as a biomarker of acute and chronic renal parenchymal damage in fUTI within the pediatric population. Methods A prospective cohort study was conducted in pediatric patients with fUTI between January 2015 and December 2018. Plasma and urine MR-proADM levels were measured at admission in addition to other laboratory parameters. After confirmation of fUTI, renal scintigraphy scans were performed during the acute and follow-up stages. A descriptive study has been carried out and sensitivity, specificity and ROC curves for MR-proADM, C-reactive protein, and procalcitonin were calculated. Results 62 pediatric patients (34 female) were enrolled. Scintigraphy showed acute pyelonephritis in 35 patients (56.5%). Of those patients, the median of plasmatic MR-proADM (P-MR-proADM) showed no differences compared to patients without pyelonephritis. 7 patients (11.3%) developed renal scars (RS). Their median P-MR-proADM levels were 1.07 nmol/L (IQR 0.66–1.59), while in patients without RS were 0.48 nmol/L (0.43–0.63) (p < 0.01). The AUC in this case was 0.92 (95% CI 0.77–0.99). We established an optimal cut-off point at 0.66 nmol/L with sensitivity 83.3% and specificity 81.8%. Conclusion MR-ProADM has demonstrated a poor ability to diagnose pyelonephritis in pediatric patients with fUTI. However, P-MR-proADM proved to be a very reliable biomarker for RS prediction.

Feasibility study of relative renal function assessment by contrast-enhanced abdominal CT in comparison to 99mTc-MAG3 renal scintigraphy

Objective: To determine the feasibility of using contrast-enhanced abdominal CT to assess relative renal function. Materials and Methods: This retrospective study reviewed data from 32 patients who had had investigations by contrast-enhanced abdominal CT and 99mTc-MAG3 renal scintigraphy, within a period of not more than 30 days. Post-processing CT images of kidneys were by manual segmentation and calculated to interpret the relative renal function. Results: There was strong correlation between CT derived relative renal function and 99mTc-MAG3 renal scintigraphy (r = 0.971, p < 0.001) and no statistically significant difference in renal function between the two techniques (p = 0.572). Conclusion: Contrast-enhanced abdominal CT can determine relative renal function as accurately as renal scintigraphy. It is an appropriate alternative method, especially in hospitals where renal scintigraphy is not available.

Every nephron deserves a second chance before nephrectomy in obstructed uropathy due to urolithiasis

Objective: In this case report, we aimed to present our clinical experience in a patient with hydronephrotic and atrophic kidney due to impacted lower ureteral stone. Case description: A 56-year-old male was admitted to our emergency department with flank pain and nausea. A computed tomography scan revealed a 3 cm stone at the distal ureter, causing severe hydroureteronephrosis. Right kidney parenchyma was extremely thin at the medial zone, and some parenchyma was apparent at the upper and lower poles. We planned renal scintigraphy, but it was impossible to perform quickly due to the active appointment list. The patient’s kidney was assumed to be atrophic/non-functioning; however, given the long waiting list for renal scintigraphy and the patient’s intractable pain, we decided to relieve the patient’s pain with urinary drainage. Nephrostomy insertion was denied because of the extra thin parenchyma. About 40 days later, the patient underwent semi-rigid ureterorenoscopy under spinal anesthesia. It was impossible to place a double J stent to the ureter because of the kinked and extremely dilated ureter. So, we decided to place an open-end 6Fr ureter catheter. DMSA renal scintigraphy showed 33% right kidney and 67% left kidney function. Conclusion: Intractable flank pain might be a predictor of functioning renal parenchyma in hydronephrotic/atrophic kidneys. Renal split function lower than 10% on DMSA scintigraphy might not be an absolute indication of nephrectomy, especially in the obstructed renal unit. Evaluation of renal function after eliminating obstruction might be more reliable.

Clinical Presentations and Usefulness of 99mTchnetium-Ethylene-Dicysteine (99mTc-EC) Renal Scintigraphy in Estimation of Thoracic Kidney Function in Children

: Thoracic kidney is a rare congenital abnormality with the lowest frequency of all renal ectopias. Most cases are discovered incidentally via routine imaging and have a benign clinical course. Here, we report three pediatric cases of thoracic kidney among 156 children with renal ectopy (1.9%). Thoracic kidney was asymptomatic in two children; in one child, it was associated with a recurrent diaphragmatic hernia. All diagnoses were made by chest ultrasonography (USG) and/or radiography in children and confirmed by computed tomography (CT) scan. Moreover, 99mtechnetium-ethylene-dicysteine (99mTc-EC) renal scintigraphy was carried out to visualize and assess the function of ectopic kidneys. All thoracic kidneys were left-sided, and their functions were comparable to their normally located counterparts. During an observation period of 5 - 10 years, two children with thoracic kidneys presented with unstable proteinuria/microalbuminuria and hypertension, respectively. The 99mTc-EC renal scintigraphy is an uncomplicated and safe method for imaging the thoracic kidneys and can be used for detecting the thoracic kidney function in children. Thoracic ectopic kidneys are associated with complications, such as hypertension and proteinuria. Children with thoracic kidneys need long-term follow-ups.

Laparoscopic transposition for crossing vessels (vascular hitch) in pure extrinsic pelvic-ureteric junction obstruction: a successful case report of a 2-year-old infant with horseshoe kidney

Background Pediatric hydronephrosis induced by pelvic-ureteric junction obstruction (PUJO) is treated by dismembered pyeloplasty (DP) via open and laparoscopic surgery. The etiology of PUJO involves both intrinsic stenosis and extrinsic compression of crossing vessels (CVs). PUJO owing to CVs is also treated by DP, as there is no consensus concerning this vascular condition. We encountered a 2-year-old infant with pure extrinsic PUJO combined with horseshoe kidney who successfully underwent laparoscopic transposition for CVs (vascular hitch). Case presentation A 2-year-old boy was prenatally diagnosed with left multicystic dysplastic kidney (MDCK) and right hydronephrosis and received a definitive diagnosis after birth. At 6 months old, renal scintigraphy revealed a non-functioning pattern in the left kidney and an obstructive pattern in the right, showing no response to furosemide loading. The patient also had recurrent urinary tract infection, and his right hydronephrosis gradually worsened. We decided to perform surgery for the right PUJO. Preoperative enhanced computed tomography detected three right renal vessels independently branching from the abdominal aorta. The middle renal vessels were located at the ventral side of the pelvis and coincident with the site of PUJO. These vessels were suspected of being CVs. The patient underwent laparoscopic surgery electively. A 5-mm trocar was inserted at the umbilicus for a 5-mm, 30° rigid scope. Two additional ports were then inserted under laparoscope inspection. The dilated right pelvis and CVs were detected after ascending colon mobilization. To confirm the pathogenesis of PUJO, the CVs were dissected and taped. After taping the CVs, an intraoperative diuretic test was performed using furosemide loading. Peristalsis of the right ureter was recognized, and the extrinsic PUJO owing to the CVs was definitively confirmed. We therefore performed transposition for the CVs (vascular hitch procedure). The CVs were mobilized in the cranial direction and those were wrapped by dilated pelvis. The post-operative course was uneventful. The renal scintigraphy findings improved and showed a favorable response of furosemide loading. Conclusions The laparoscopic vascular hitch procedure is minimally invasive and effective for extrinsic PUJO due to CVs. Anastomotic stricture after Anderson and Hynes DP can be prevented by appropriate patient selection.