UROLOGICAL SURVEY   ( Download pdf )

 

PEDIATRIC UROLOGY

Natural History of Patients With Multicystic Dysplastic Kidney-What Followup Is Needed?
Onal B, Kogan BA
Division of Urology, Albany Medical College, Albany, New York, USA
J Urol. 2006; 176: 1607-11

  • Purpose: Most clinicians recommend followup with annual ultrasound for patients with multicystic dysplastic kidney. The aim of this study was to determine whether followup ultrasound provides any clinical benefit.
  • Materials and Methods: We retrospectively reviewed the charts of 73 patients who were diagnosed with multicystic dysplastic kidney between October 1991 and August 2005. Data were analyzed with respect to patient characteristics and followup information.
  • Results: We identified 61 patients (43 boys and 18 girls) with adequate followup. A total of 49 patients (80%) were diagnosed prenatally and 12 (20%) postnatally. Associated urological anomalies were noted in 16 patients (26%). Median followup was 2.6 years (range 6 months to 37.5 years). Ultrasound examinations showed complete involution in 25 patients (41%) and partial regression in 18 (30%). The size of the multicystic dysplastic kidney increased in 1 patient (1.6%) and was unchanged in 17 (28%) without any pathological manifestations. Median age at complete involution was 2.1 years (range 36 days to 13.7 years). Patients with contralateral compensatory hypertrophy had more rapid complete involution. Urinary tract infection developed in 6 patients, of whom 1 was ultimately found to have reflux and 1 had ureteropelvic junction obstruction.
  • Conclusions: In our patients with unilateral multicystic dysplastic kidney ultrasound provided little clinically important information. Our data and a review of the literature suggest that once the diagnosis is made, no urological followup is needed. The primary care provider should monitor patients with multicystic dysplastic kidney for hypertension, abdominal mass and urinary tract infection.

  • Editorial Comment
    This is an interesting review of 73 patients between 1991 and 2005 diagnosed with multicystic kidney disease. Of these 61 patients, 43 boys and 18 girls, had follow up with ultrasound postnatally and VCUG or renal scan. Median age at diagnosis was 1.5 years and median follow up was 2.6 years with the median number of ultrasounds per patient was 4. Associated urologic anomalies were found in 16 patients. Most were vesicoureteral reflux. Four had ureteroceles and 1 had a contralateral ureteropelvic junction obstruction. The authors evaluated their patients thoroughly for hypertension and development of kidney tumors and none of their patients developed either. Only one of their patients had an increase in size in the multicystic kidney. They conclude that multicystic dysplastic kidney patients should have a postnatal ultrasound and VCUG and only patients with associated urologic anomalies should have continual follow up.
    This data seems to mirror that which is seen in the medical literature and there is very little evidence that multicystic dysplastic kidney patients will develop hypertension at any increased rate or develop a kidney tumor. Many have recommended that the ultrasounds be done at least until age 8 or even puberty. In this study, the actual follow up is relatively short but their lack of findings seems to validate their conclusions that routine imaging is unnecessary.

Dr. Brent W. Snow
University of Utah Health Sci Ctr
Division of Urology
Salt Lake City, Utah, USA