Primary intrarenal/perirenal neuroblastoma mimicking Wilms' tumor at presentation in a 5-year-old girl: a case report from Siriraj hospital.

Primary intrarenal/perirenal neuroblastoma (NB) is NB that primarily arises in intrarenal and/or perirenal regions. Regarding its location, this tumor can mimic Wilms' tumor a more common pediatric renal tumor at presentation. Owing to diference in clinical management andprognosis, it is crucial to distinguish primary intrarenal/perirenal NB from Wilms' tumor at the time of diagnosis. Recognition of its characteristic features, which are distinctive from its adrenal counterpart, is helpful to guide to the correct diagnosis and proper treatment. However,; due to its rarity with less than 100 cases described in English literatures, the characteristics of primary intrarenal/perirenal NB have not been widely studied The authors, therefore, report this case of primary intrarenal/perirenal NB, which occurred in right kidney of a 5-year-old Thai girl in order to illustrate the characteristic features of this tumor To the authors'knowledge, this case is the first case ofprimary intrarenal/perirenal NB that has been reported in Thailand

Sonographic renal length and volume of normal Thai children versus their Chinese and Western counterparts.

BACKGROUND: Renal size is an important indicator in the diagnosis of renal diseases and urinary tract infections in children. PURPOSE: The purpose of this study is twofold. First, it aimed to measure the renal length and calculate the renal volume of normal Thai children using 2-dimensional ultrasonography (2D-US) and study their correlations with somatic parameters. Second, it aimed to compare the age-specific renal size of normal Thai children with the published data of their Western and Chinese counterparts. METHODS: A total of 321 children (150 boys, 171 girls; age, 6-15 years) with a normal renal profile were prospectively recruited. All subjects underwent 2D-US by an experienced pediatric radiologist and the renal length, width, and depth were measured. Renal volume was calculated using the ellipsoid formula as recommended. The data were compared between the left and right kidneys, the sexes, and various somatic parameters. The age-specific renal lengths were compared using a nomogram derived from a Western cohort that is currently referred by many Thailand hospitals, while the renal volumes were compared with the published data of a Chinese cohort. RESULTS: No statistically significant difference (P<0.05) was found between sexes or the right and left kidneys. The renal sizes had strong correlations with height, weight, body surface area, and age but not with body mass index. The renal length of the Thai children was moderately correlated (r=0.59) with that of the Western cohort, while the age-specific renal volume was significantly smaller (P<0.05) than that of the Chinese children. CONCLUSION: Therefore, we concluded that the age-specific renal length and volume obtained by 2D-US would vary between children in different regions and may not be suitably used as an international standard for diagnosis, although further studies may be needed to confirm our findings.

A multivariable assessment of renal size and growth of scarred kidneys in children.

PURPOSE: We applied a recently developed multivariable renal size nomogram to sonographic measurements of kidneys with known scarring to assess systematically their sizes and growth patterns compared to normal kidneys. MATERIALS AND METHODS: We retrospectively reviewed renal sonograms of 138 kidneys (55 right and 83 left) with known scarring. The sizes of these scarred kidneys were compared to the 95% prediction limits calculated according to the multivariable renal size nomogram, adjusting for patient age, gender, race, weight and height. The growth of scarred kidneys was evaluated by fitting individual linear regression lines using serial sonographic measurements and comparing the results with normal predicted values. RESULTS: The sizes of 89.1% of the right and 81.9% of the left scarred kidneys were within the 95% normal prediction limits. Only 17 of 138 of the scarred renal units showed smaller kidney sizes compared to the normal prediction limits. Serial sonographic measurements revealed that compared to normal predicted values, 24 of 60 left and 16 of 38 right scarred kidneys grew within +/- 1.0% annually of the boundaries of normal predicted values. Additionally, 8 left and 7 right scarred kidneys indicated a growth rate of more than 1% annually higher than the normal predicted values. CONCLUSIONS: Multivariable analyses of renal sonographic measurements provided a dynamic picture of kidney well-being in children with renal scarring. We found that the majority of scarred kidneys were within the normal predicted limits, and a large proportion of these kidneys grew equally well compared to those with normal anatomy.