Jeng-Daw Tsai

Screening Young Children with a First Febrile Urinary Tract Infection for High-grade Vesicoureteral Reflux with Renal Ultrasound Scanning and Technetium-99m-labeled Dimercaptosuccinic Acid Scanning

OBJECTIVE To evaluate the predictive value of renal ultrasound scanning and 99m-Technetium-dimercaptosuccinic acid (DMSA) scintigraphy for high-grade vesicoureteral reflux (VUR) in young children with a first urinary tract infection (UTI). STUDY DESIGN The medical records of children who had been examined with renal ultrasound scanning, DMSA scanning, and voiding cystourethrography (VCUG) were reviewed. The findings of renal ultrasound scanning, DMSA scanning, and their predictive values were evaluated. RESULTS Of 699 children, high-grade VUR (grades III-V) was diagnosed in 119 (17.0%). Signs of renal hypodysplasia (OR, 16.15), cyclic dilatation of pelvicaliceal system (OR, 11.73), hydroureter (OR, 4.00) with renal ultrasound scanning, and renal hypodysplasia (OR, 8.78), acute pyelonephritis (OR, 2.76) with DMSA scanning were associated with high-grade VUR. The sensitivities for high-grade VUR of ultrasound scanning alone (67.2%) or DMSA scanning alone (65.5%) were not as good as that of a both-test strategy, which had a sensitivity rate of 83.2%. The negative predictive value of the both-test strategy was 91.5%. CONCLUSION Renal ultrasound scanning and DMSA scanning both should be routinely performed in children with a first febrile UTI. VCUG is only indicated when abnormalities are apparent on either ultrasound scanning or DMSA scanning or both.

Intermittent hydronephrosis secondary to ureteropelvic junction obstruction: clinical and imaging features.

OBJECTIVE. We sought to assess the clinical and imaging findings in intermittent hydronephrosis secondary to ureteropelvic junction obstruction, with particular emphasis on the characteristic ultrasonographic findings. METHODS. This prospective, longitudinal, observational study included all children who had intermittent ureteropelvic junction obstruction and presented with abdominal pain over 6 years. Renal ultrasound was used as an initial screening tool to detect intermittent hydronephrosis. Renal ultrasonography was repeated every 1 to 2 days to record serial changes from the symptomatic to the asymptomatic stage. Their clinical manifestations and imaging findings were studied. RESULTS. Eighteen patients (14 boys, 4 girls) were studied. Most had sharp pain that began acutely and typically lasted for <2 days. Most of the children (16 of 18) had nausea and vomiting that accompanied the pain. The acute episode generally resolved spontaneously and was followed by a pain-free interval that ranged from days to months. Factors that predisposed to an attack included increased water intake, vigorous exercise, or bladder distention. All patients had clearly demonstrable obstruction of the renal pelvis during an acute attack, a finding that diminished or resolved during the symptom-free intervals. During convalescence, all patients had renal pelvic wall thickening on ultrasonography. This finding appeared on the second or third day after a painful episode subsided, persisted for 6 to 9 days, and then disappeared in the symptom-free stage. Pyeloplasty was performed in 17 patients, none of whom had recurrent pain on follow-up. Extrinsic obstructions were found in 9 patients. CONCLUSIONS. The keys to diagnosis are awareness of the syndrome, a detailed history, and immediate and serial imaging studies during painful crises. A thickened renal pelvic wall during convalescence is an important ultrasonic sign of intermittent hydronephrosis.

Analysis of genes encoding laminin β2 and related proteins in patients with Galloway–Mowat syndrome

Galloway–Mowat syndrome (GMS) is a rare autosomal recessive disorder characterized by early onset nephrotic syndrome and microcephaly with various anomalies of the central nervous system. GMS likely represents a heterogeneous group of disorders with hitherto unknown genetic etiology. The clinical phenotype to some extent overlaps that of Pierson syndrome (PS), which comprises congenital nephrotic syndrome and distinct ocular abnormalities but which may also include neurodevelopmental deficits and microcephaly. PS is caused by mutations of LAMB2, the gene encoding laminin β2. We hypothesized that GMS might be allelic to PS or be caused by defects in proteins that interact with laminin β2. In a cohort of 18 patients with GMS or a GMS-like phenotype we therefore analyzed the genes encoding laminin β2 (LAMB2), laminin α5 (LAMA5), α3-integrin (ITGA3), β1-integrin (ITGB1) and α-actinin-4 (ACTN4), but we failed to find causative mutations in these genes. We inferred that LAMA5, ITGA3, ITGB1, and ACTN4 are not directly involved in the pathogenesis of GMS. We excluded LAMB2 as a candidate gene for GMS. Further studies are required, including linkage analysis in families with GMS to identify genes underlying this disease.

Segmental multicystic dysplastic kidney in children: clinical presentation, imaging finding, management, and outcome

PURPOSE The aim of the study was to assess the presentation, imaging findings, management, and outcome of segmental multicystic dysplastic kidney (MCDK) in children. MATERIALS AND METHODS Six patients with segmental MCDK were diagnosed and observed at our hospital. We reviewed the medical records to collect data on initial symptoms, results of imaging studies, associated urinary tract anomalies, operation, and outcome. RESULTS Three patients had abnormal prenatal ultrasound and were diagnosed by further postnatal imaging; they were asymptomatic after birth. The other 3 children presented with a renal mass, recurrent urinary tract infection, or urinary incontinence. Five patients had associated ipsilateral or contralateral urinary tract abnormalities, including vesicoureteral reflux, ureterocele, duplex collecting system, ureteropelvic junction stenosis, and ectopic ureter. Lower tract reconstruction was performed in 3, and open biopsy was done in 1 child. None underwent partial or total nephrectomy, and all had involution of the cysts for a mean of 40 months. CONCLUSIONS Most of the cases occur in the upper pole of a duplex kidney and often involute spontaneously without significant complication. The clinical presentation and imaging findings depend on the associated anomalies and complications. Although the latter may require surgery to resolve, segmental MCDK itself rarely requires resection.

Paecilomyces Lilacinus Peritonitis Complicating Peritoneal Dialysis Cured by Oral Voriconazole and Terbinafine Combination Therapy

Fungal peritonitis (FP) is a serious complication in patients on continuous ambulatory peritoneal dialysis (CAPD). We report a case of CAPD-related FP caused by Paecilomyces lilacinus in a 15-year-old uraemic boy. The infection was successfully treated by combination therapy consisting of oral voriconazole and terbinafine, which has not been previously reported in the treatment of FP.

The Role of Percutaneous Renal Biopsy in the Diagnosis and Management of Renal Diseases in Children

We undertook a retrospective study to determine the proportion of patients in whom diagnostic and therapeutic changes were made as a result of renal biopsy. From April 1992 to March 1997, 111 renal biopsies were performed on 109 children aged 11 months to 18 years at our hospital. Adequate renal tissue was obtained in 106 cases (95.3%). Gross hematuria was observed in 12 cases (10.8%). Perirenal hematoma was found in 8 cases (7.2%) by ultrasound. A scoring system was designed to assess if diagnosis and therapy are affected as a result of renal biopsy. For diagnosis, the score was 0 when no additional information was obtained; 1 when the diagnosis was confirmed or ruled out; and 2 when the diagnosis was changed after biopsy or the pathologic findings provided a definite prognosis. For therapy, the score was 0 when the management was not changed after biopsy; 1 when the clinical diagnosis was confirmed and yielded a change in management; and 2 when the diagnosis and management were changed after biopsy. We found the benefit score for diagnosis was 0 in 2 (1.9%) of the 106 biopsied cases; 1 in 78 (73.6%), and 2 in 26 (24.5%). The benefit score for therapy was 0 in 62 (58.5%); 1 in 24 (22.6%); and 2 in 20 (18.9%). Therapeutic change always occurred in the biopsied patients with steroid resistant nephrotic syndrome and systemic diseases with renal involvement, and occasionally occurred in frequent relapsing nephrotic syndrome, steroid dependent nephrotic syndrome and asymptomatic proteinuria plus hematuria. It never occurred in patients with acute or chronic renal failure and hematuria. We conclude that renal biopsy is a safe and efficient procedure in pediatric patients. It can markedly change diagnosis and therapy, and can increase the likelihood for a more rational management of children with renal disease.

Why is hypercalciuria absent at diagnosis in some children with ATP6V1B1 mutation

We try to explain why hypercalciuria is absent at diagnosis in some children with an ATP6V1B1 mutation. A 5-month-old girl presented with distal renal tubular acidosis (dRTA) and sensorineural hearing loss. Direct sequencing of the ATP6V1B1 genes disclosed a new homozygous mutation (452 delT) in exon 13. In particular, an absence of hypercalciuria and a normal level of parathyroid hormones were noted. After alkaline therapy, the signs of nephrocalcinosis improved on ultrasound during follow-up. After a review of the literature regarding patients with ATP6V1B1 gene mutations, a young age seemed to be an important factor for normocalciuria. The probable mechanism of normocalciuria and a dynamic mode of calcium excretion in patients with dRTA is proposed. The determinant factors include the degree of systemic acidosis, urine pH, genetic polymorphisms, age, dietary factors, and volume status. Low sodium intake may be a major determinant of normocalciuria in these patients. It is suggested that hypercalciuria is usually absent at diagnosis of dRTA in young infants. Blood pH, plasma bicarbonate concentration, urinary citrate levels, and growth catch-up may be better indicators of adequate alkali therapy in normocalciuric children. Volume contraction, low salt content in infant formula, and alkaline urine in young infants are likely to account for the increased calcium reabsorption.

Reappraisal of the effectiveness of 99mTc-dimercaptosuccinic acid scans for selective voiding cystourethrography in children with a first febrile urinary tract infection

Recent studies have yielded conflicting results regarding the ability of technetium‐99m dimercaptosuccinic acid (99mTc‐DMSA) renal scans for identifying high‐grade vesicoureteral reflux (VUR) in children with a first febrile urinary tract infection (UTI). This study aimed to reevaluate the effectiveness of 99mTc‐DMSA renal scans for selective voiding cystourethrography (VCUG) in children with a first febrile UTI. The medical records of children aged ≤ 5 years who were admitted with a first febrile UTI were retrospectively reviewed. Ultrasonography (US) and DMSA renal scans were performed within 3–5 days after admission, and VCUG was performed 7–10 days after antibiotics treatment. A total of 653 children were enrolled for analysis, including 579 patients aged < 2 years (Group A) and 74 patients aged 2–5 years (Group B). In Group A, DMSA scans were abnormal for 346 patients (59.8%), and normal for 233 patients (40.2%). High‐grade VUR was present in 99 of 346 patients (28.9%) with abnormal DMSA scans, but present in only 16 of 233 patients (6.9%) with normal DMSA scans (p < 0.001). Regarding the prediction of high‐grade VUR, the sensitivity and negative predictive value (NPV) for the DMSA scans were 86.1% and 93.1%, respectively. In Group B, DMSA scans were abnormal for 36 patients (48.6%), and normal for 38 patients (51.4%). High‐grade VUR was present in 12 of 36 patients (33.3%) with abnormal DMSA scans, whereas none of the 38 patients with normal DMSA scans had high‐grade VUR (p < 0.001). The sensitivity and NPV of the DMSA scans were both 100%. Using the selective VCUG strategy, approximately 40% of Group A patients and 50% of Group B patients could be spared an unnecessary VCUG, respectively. Our study results suggest that 99mTc‐DMSA renal scans are effective in identifying children with a first febrile UTI for selective VCUG.

Functional independence of Taiwanese children with VACTERL association

VACTERL association is a non‐random association of birth defects, which may include anomalies of the vertebral column, limbs, kidneys, and heart; anal atresia; tracheoesophageal fistula; and esophageal atresia. The presence of two or more of the defects establishes the diagnosis. The aim of our study is to describe the functional independence of children with VACTERL association and compare the results to unaffected children. These results will enable clinicians to provide more realistic prognostic information to parents and families. We used the WeeFIM questionnaire to assess the functional skills of 23 patients who had been diagnosed with VACTERL association at Mackay Memorial Hospital, Taipei, Taiwan, from June 1994 to June 2009. The total WeeFIM scores and sub‐scores for three domains (self‐care, mobility, and cognition) correlated significantly with age (P < 0.01). The scores were generally within the same range as those of unaffected Chinese children, although our subjects had slightly inferior scores on six items, including bowel, chair transfer, stairs, expression, social interaction, and problem solving. In conclusion, the daily functional skills of Taiwanese children with VACTERL association were similar to those of unaffected children.

Hemolytic Uremic Syndrome Caused by Enteroviral Infection

A 4-year-old boy presented with enteroviral infection complicated with atypical hemolytic uremic syndrome (aHUS). Enterovirus RNA was detected by reverse transcription polymerase chain reaction (RT-PCR) of both blood and kidney biopsy specimens. A survey of the complement system did not reveal a specific complement defect. Supportive therapy with blood components transfusion, plasma therapy, and immunosuppressants was administered, however, renal function did not recover. The results of this report demonstrate that the enterovirus is the cause of aHUS.