Are There Any Differences in the Neural and Extracellular Matrix Proteins Density Between Children and Adults with Intrinsic Ureteropelvic Junction Obstruction?

Abstract

Objective: To compare changes in connective, neural and muscle tissues, and extracellular matrix in child and adult patients so that we can create a more objective view on the timing of surgery. Materials and Methods: Twenty-six patients, who were operated for ureteropelvic junction (UPJ) obstruction in our clinic between September 2014 and May 2016, were included in the study. For the evaluation of connective tissue, Masson's trichrome staining was used. Muscle, extracellular matrix elements and neural tissue were evaluated with immunohistochemistry using alpha-smooth muscle actin (α-SMA), Tenascin C and S100, respectively. Microscopically, the tissues were scored according to their staining density (0: No staining; 1: Minor; 2: Moderate, 3: Dense). Results: There were 12 children and 14 adults in the study groups. The initial evaluation showed no statistically significant difference between studied tissue types with respect to staining density for all parameters (Masson: p=0.414, α-SMA: p=0.204, Tenascin-C: p=0.264, S100: p=0.534). There was no statistically significant correlation between staining density and renal function percentage of the affected kidney (Masson: r=0.454, p=0.051 -α-SMA: r=-0.323, p=0.177 -Tenascin-C: r=0.290, p=0.229 -S100: r=-0.080, p=0.744). Conclusion: Our preliminary study showed some structural changes between adult and child patients but there is no statistically significant difference between the groups with respect to staining density scores. These results state that although UPJ obstruction is an ongoing process, there is no correlation between the histological deterioration degree of the UPJ segment and the loss on renal function for both children and adults. Keywords: Extracellular matrix, immunohistochemistry, muscle tissue, connective tissue, neural tissue, ureteropelvic junction Amaç: Cerrahi zamanlaması üzerine daha objektif bir görüş oluşturabilmek için çocuk ve erişkin hastaların bağ, sinir, kas dokuları ve ekstraselüler matriks proteinlerindeki değişiklikleri karşılaştırmaktır. There are lots of studies on the histology of the obstructed segment of UPO patients. Although there are some conflicting results, most of the studies performed to date state that while muscle and neural tissue decrease in UPO, connective tissue and extracellular matrix proteins increase. All these studies have been conducted whether on children or adults. This is the first study that compared the specimens from adult and child population. Our study will help us better understand the progression of ureteropelvic junction obstruction throughout life and create a better understanding on the timing and need of surgery.

Ureteropelvic Junction Obstruction (UPJO)

“…This condition is two times more common in boys than in girls, and the left side of the kidney is more often affected than the right side. 1,2…”

“…Ureteropelvic junction obstruction is characterized by urinary flow impairment from the renal pelvis to the ureter and is one of the most common causes of antenatal hydronephrosis. 1 It occurs in 1/1000 to 1/2000 of newborns and may have increased due to the widespread use of maternal ultrasound. [1][2][3] Frequently, UPJO is seen more in boys than in girls, and the left side of the kidney is more often affected than the right side.…”

“…1 It occurs in 1/1000 to 1/2000 of newborns and may have increased due to the widespread use of maternal ultrasound. [1][2][3] Frequently, UPJO is seen more in boys than in girls, and the left side of the kidney is more often affected than the right side. Most cases of UPJO are congenital; however, some remain asymptomatic into adulthood.…”