Urological emergency in neonates with congenital hydronephrosis

Giant Bilateral Hydronephrosis in A Newborn-A Case Report

BACKGROUND

Prenatal hydronephrosis is common and may vary in size. Although mostly unproblematic, it may be a sign of urinary tract obstruction of differing severity.

CASE DIAGNOSIS/TREATMENT

We present a boy with prenatally detected bilateral giant hydronephrosis. A prenatal ultrasound showed the whole abdominal cavity of the fetus filled with urine. Kidney parenchyma could not be seen. The boy was born at 34 + 1 weeks' gestation. After delivery, he showed a severely distended abdomen. Insertion of a nasogastric tube was not possible, and he had to be intubated due to respiratory distress. A bilateral percutaneous nephrostomy was performed immediately. After a few hours, he could be stabilized and extubated. An ultrasound on the following day showed two kidney units with normal kidney parenchyma of normal size. The initially slightly elevated serum creatinine level normalized within one week. An antegrade pyelography via the nephrostomy tubes showed bilateral ureteropelvic junction obstruction.

CONCLUSION

Severe bilateral hydronephrosis may be associated with good outcome and well-preserved kidney function. Prenatal counseling should be done carefully, with discussion of different treatment possibilities and without definitive prediction of outcome.

Acute abdominal pain localized in right iliac fossa: Not always acute appendicitis. A case of giant hydronephrosis in an 8-year-old boy and literature overview

Abdominal pain is a frequent complaint in children, leading them to seek medical attention. It can have several causes, though acute appendicitis is the most feared diagnosis when pain is localized in the right iliac fossa. We report a case of an 8-year-old boy with the complaint of acute abdominal pain, initially referred by his family doctor to a radiologist for an abdominal ultrasound (US) for suspected acute appendicitis. A fortuitous diagnosis of giant hydronephrosis (GH) was made upon admission, which showed the palpation of a huge poorly delineated abdominal mass that was probably missed at the previous examination by the general physician (GP). Uroscan confirmed the diagnosis of GH secondary to obstruction at the ureteropelvic junction. A renal MAG3 (mercaptuacetyltriglycine) scan showed revealed differential renal function (15%) on the right side, normal on the left side. Robot-assisted right pyeloplasty with the transposition of right lower polar vessels via trans-peritoneal laparoscopy was performed, and JJ probe left in-situ for a month. The boy is doing well and is under active follow-up. GH is rare; its diagnosis requires both meticulous examination and a high index of suspicion. Its management is uncodified but in children, pyeloplasty is preferred to nephrectomy.

Alteration of N6-methyladenosine epitranscriptome profiles in bilateral ureteral obstruction-induced obstructive nephropathy in juvenile rats

BACKGROUND

Urinary tract obstruction is a common cause of renal failure in children and infants, and the pathophysiological mechanisms of obstructive nephropathy are largely unclear. It has been reported that m6A modulation is involved in renal injury. However, whether m6A RNA modulation is associated with obstructive nephropathy has not yet been reported. The aim of this study was to investigate the m6A epitranscriptome profiles in the kidneys of bilateral ureteral obstruction (BUO) in young rats.

METHODS

The total level of m6A in the kidneys was measured by liquid chromatography-tandem mass spectrometry. The mRNAs of related genes were detected by real-time PCR. Methylated RNA immunoprecipitation sequencing was performed to map the epitranscriptome-wide m6A profile.

RESULTS

Global m6A levels were increased after BUO, and the mRNA expression levels of m6A methyltransferases and demethylases were significantly decreased in BUO group rat kidneys; the expression levels of EGFR and Brcal were significantly upregulated, while the mRNA expression levels of Notch1 were downregulated (P < 0.05). A total of 154 genes associated with 163 m6A peaks were identified.

CONCLUSION

The m6A epitranscriptome was significantly altered in BUO rat kidneys, which is potentially implicated in the pathophysiological processes of obstructive nephropathy.

IMPACT

The m6A RNA modification was associated with the process of renal injury in ureteral obstructive nephropathy by participating in multiple dimensions. The dysregulation of m6A methyltransferases and demethylases may be related to the pathophysiological changes of BUO-induced obstructive nephropathy. The m6A RNA modulation of the genes EGFR, Brca1, and Notch1 that were related to the regulation of aquaporin2 might be the potential mechanism for the polyuresis after ureteral obstruction.

Percutaneous Nephrostomy in the Neonatal Period: Indications, Complications, and Outcome-A Single Centre Experience

PURPOSE

The purpose of this study was to evaluate the indications, technique for percutaneous nephrostomy (PCN) insertion, the complications related to PCN, duration of PCN, and outcome following PCN removal regarding the kidney function.

MATERIAL AND METHODS

Medical charts of 31 neonates (22 boys and 9 girls, mean age 13.9 days) treated with 43 PCN were reviewed. Collected data included indications for PCN, PCN complications, duration of PCN, and outcome of these patients by analysing the kidney function.

RESULTS

The indications for PCN insertion were obstructive urinary tract dilation in 24 neonates (four with associated infection), and non-obstructive urinary tract dilation with urosepsis or pyonephrosis in seven cases. Primary technical success of PCN placement using Seldinger technique was 97.7%. The following complications were reported: self-limited post-procedural bleeding into the pelvicalyceal system in two, chronic microscopic haematuria in five, and clinically manifested urinary tract infection in five children. Four PCN were dislocated. Cellulitis was present at the skin entry of 5 PCN, urinary leak in 5 PCN, and mechanical damage of 5 PCN. Eight PCN had to be replaced. Mean duration of PCN was 5 months. Kidney insufficiency was detected in 5/29 children with the mean follow-up of 3.9 years.

CONCLUSIONS

PCN is a safe, effective transient solution in neonates with pyonephrosis or when surgery of obstructed urinary system has to be postponed. The rate of minor complications increased with PCN duration. If kidney insufficiency is present after PCN removal, it is related to the complexity of kidney anomalies.

Aquaporin1-3 expression in normal and hydronephrotic kidneys in the human fetus

BACKGROUND

Decreased expression of the renal aquaporin (AQP) protein family is associated with hydronephrosis in adult humans and animals. However, the expression of AQPs, especially subtypes AQP1-3, which play a core role in the urinary concentration function, in hydronephrotic human fetuses is not clear. The aim of this study is to investigate the expression of the AQP1-3 in normal and hydronephrotic human fetal kidneys.

METHODS

Twenty-one normal and six hydronephrotic kidney (HK) samples were harvested from abortive fetuses. Meanwhile, seven normal adult human kidney samples were collected as positive controls. Quantitative real-time PCR, western blotting, and immunohistochemistry were used to analyze the expression of AQP1-3.

RESULTS

Both the protein and messenger mRNA expression levels of AQP1-3 increased with gestational age in the normal fetuses, but the levels were significantly lower than those in the adult tissues and significantly higher than those in the hydronephrotic fetuses at the same gestational age.

CONCLUSIONS

The increased expression of AQP1-3 with gestational age in the fetal kidney may indicate maturation of the urinary concentrating ability. The lower expression of AQP1-3 in HKs may reflect a maturation obstacle with regard to urinary concentration in human hydronephrotic fetuses.

Late recurrence of symptomatic hydronephrosis in patients with prenatally detected hydronephrosis and spontaneous improvement

PURPOSE

Most prenatal hydronephrosis improves or resolves spontaneously with conservative treatment. However, late recurrence of prenatal hydronephrosis sometimes develops after improvement. To define the need for continuous observation after improvement of hydronephrosis, long-term followup was carried out in children with prenatally diagnosed hydronephrosis.

MATERIALS AND METHODS

We retrospectively evaluated 344 cases initially presenting between July 1991 and June 2004 with prenatally detected hydronephrosis that persisted postnatally. Subjects underwent periodic assessment of hydronephrosis using ultrasonography and diuretic renography. Indications for surgery were associated symptoms, enlarged renal pelvis, worsening hydronephrosis on sequential ultrasonography and decrease in differential renal function greater than 5%. Mean duration of followup was 10.1 years.

RESULTS

Of the 394 kidneys followed nonoperatively 4 (1%) displayed worsened hydronephrosis after spontaneous improvement. Initial grade of hydronephrosis was grade I in 1 patient, grade II in 1, grade III in 1 and grade IV in 1. On serial ultrasonographic followup hydronephrosis worsened to grade IV in 3 kidneys and to grade III in 1 kidney. Mean patient age at worsening of hydronephrosis was 40 months (range 22 to 60). All 4 patients presented with clinical symptoms. All patients who underwent pyeloplasty displayed no symptoms, and had improved hydronephrosis after pyeloplasty.

CONCLUSIONS

Prenatally detected hydronephrosis can worsen after spontaneous postnatal improvement. Long-term followup is not required after improvement of prenatal hydronephrosis. However, pediatric urologists need to tell the parents that the child should undergo ultrasonography if clinical symptoms develop.