Primary vesicoureteral reflux: A 26-year experience in a single centre

Risk factors for renal scarring and clinical morbidity in children with high-grade and low-grade primary vesicoureteral reflux

INTRODUCTION

Primary vesicoureteral reflux (VUR) is associated with urinary tract infections (UTIs) and renal damage. However, the importance of early diagnosis of VUR has been questioned. Moreover, most studies have few patients with high-grade VUR. Hence, we retrospectively analyzed a large cohort of patients with primary high-grade and low-grade VUR and assessed risk factors for renal damage and clinical morbidity.

MATERIAL AND METHODS

We included patients (<18 years) at diagnosis with low-grade (1-3) or high-grade (4-5) primary VUR and noted their clinical history and presence of hypertension, low eGFR (<60ml/in/1.73 m²), renal scarring (focal or generalised) and reduced differential renal function (DRF; <45%). Risk factors were assessed (in patients and renal units) by logistic regression and generalised estimating equation.

RESULTS

Of 399 primary VUR patients, 255 (64%) had high-grade VUR. Indications for voiding cystourethrogram were recurrent UTI (38%), first UTI (28%) and antenatal hydronephrosis (17%). At diagnosis, 252 (65%) had renal scars (focal in 170 [44%], generalised in 82 [21%]), and 188 (47%) had reduced DRF. High-grade VUR patients were more likely than low-grade VUR patients to have renal scarring (75% vs. 49%, p < 0.01), low eGFR (23% vs. 13%, p = 0.04) and significant hypertension (26% vs. 13%, p = 0.02). High-grade VUR was associated with generalised scars (odds ratio [OR] 11, p < 0.001), focal scars (OR 3.1, p < 0.001) and reduced DRF (OR 2.3, p < 0.001) shown in the table. Male sex was a risk factor for generalised scars (OR 2.3, p = 0.005). Focal scars were associated with recurrent UTIs (OR = 1.8, p = 0.004) and reduced DRF (OR 1.4, p = 0.027). Patients with multiple focal scars were diagnosed at an older age (2 years [1,4] than those with single scars (1.5 years [1,4] or no scars (1 year [0, 3]), p = 0.04).

DISCUSSION

The prevalence of renal damage and clinical morbidity at VUR diagnosis was higher than other studies. High-grade VUR patients had a greater prevalence of renal damage, low eGFR and hypertension than low-grade VUR patients and was a risk factor for focal scars, generalised scars and reduced DRF. Focal scars were independently associated with recurrent UTI. Those with multiple scars were diagnosed later than those with single scars or no scars.

CONCLUSIONS

High-grade VUR was associated with renal damage and clinical morbidity. Our study highlights the importance of diagnosing VUR early to identify patients who may warrant long-term follow-up and intervention to minimize morbidity.

Risk factors affecting the prognosis of urinary tract infection in Chinese pediatric patients: Single-center experience

BACKGROUND

Urinary tract infection (UTI) is common in children. The purpose of this retrospective study was to determine the various risk factors that usually affect the prognosis of UTI in children diagnosed with the disease.

METHODS

In the present retrospective study, we enrolled all pediatric patients diagnosed with UTI and hospitalized between 1 January 2013 and 31 July 2016 at Nanjing Children's Hospital. We then collected all the relevant patient clinical demographics and characteristics.

RESULTS

The study involved 2,092 pediatric patients diagnosed with UTI. On logistic regression analysis, factors that could affect the prognosis of pediatric UTI were complications, hospitalization, intensive care unit (ICU) admission, type of UTI, urine culture results, blood lymphocytes, urine nitrites (NIT) and antibiotics (unstandardized coefficients, 0.06, <0.001, -0.28, 0.32, <0.001, 0.01, -0.11, 0.01, respectively, all P < 0.001).

CONCLUSION

Complications, hospitalization, type of UTI, urine culture results, blood lymphocytes, and antibiotics had a significant, positive association with UTI prognosis. Meanwhile, ICU admission and urine NIT had a negative association with prognosis.

What Did We Find From Imaging Studies in Childhood Urinary Tract Infection and Which Studies Are Mandatory?

OBJECTIVE

To evaluate the imaging results of childhood urinary tract infection (UTI) in our setting, and examine if it would be appropriate to apply the recent guideline changes regarding imaging studies as routine practice in Thailand.

METHODS

Medical records of children with UTI aged 0-15 years were reviewed, with focus on renal ultrasound (RUS), cystogram, and ^99mTc dimercaptosuccinic acid (DMSA) renal scan results to determine congenital anomalies of the kidney and urinary tract (CAKUT) and renal damage. Mild CAKUT was defined as primary vesicoureteral reflux grades I-III or isolated hydronephrosis, and all other abnormalities were defined as severe CAKUT.

RESULTS

A total of 142 boys and 129 girls had at least 1 imaging study after UTI. Their median (interquartile range) age was 1.0 (0.5-2.7) year: 0.7 and 1.4 years for boys and girls, respectively (P = .006). A total of 262 children had an RUS performed, of which 99 (37.8%) were abnormal. Cystograms were performed in 221 children, from which 83 (37.6%) CAKUTs were detected, and 108 children had a DMSA performed, of which 53 (49.1%) were abnormal. Overall, CAKUTs were detected in 148 (54.6%) children, of which 43 were severe. RUS together with cystogram provided higher sensitivity (100% vs 88.9%) and specificity (53.8% vs 42.4%) to detect severe CAKUT than RUS together with DMSA.

CONCLUSION

A CAKUT was detected in more than half of the children with first UTI, with one-third having severe CAKUT. In our setting, RUS combined with cystogram is still the most reliable way to detect potentially harmful post-UTI problems, and the new western guidelines are not appropriate.