Abstract
Objective: The study was performed to evaluate the clinical course and renal outcome of patients with multicystic dysplastic kidney (MCDK). Methods: We retrospectively reviewed the medical records of 44 infants born at and followed up at King Abdul-Aziz Medical City, Riyadh, KSA, between January 2010 and December 2015. Available clinical and radiological records were reviewed. Outcomes of simple and complex, right-and left-sided MCDK were compared using paired sample t-test and Chi-Square tests as appropriate. Results: MCDK was found in the left side 22 infants (50%). There were other associated renal abnormalities in 63.6%; however; only 6.8% of the infants had other associated extrarenal abnormalities. Vesicoureteric reflux (VUR) was diagnosed in 7 infants (16%) of the study population. The median duration of follow-up was 36 range (12-84) months. At follow-up, urinary tract infections were diagnosed in 7 (16%) and 3 (6.8%) patients had hypertension requiring medical treatment. Follow-up renal ultrasound scans confirmed compensatory hypertrophy of the contralateral kidney in 31 (71%) of patients. Complete involution of the dysplastic kidney was seen in 10 (27.7%) of patients whereas partial involution of the dysplastic kidney was seen in 20 (45.5%) patients at follow-up. In 14 patients (31.8%), there were no changes in the size of the dysplastic kidney at follow-up. There were 28 infants with complex MSDK (associated with other renal abnormalities). Compared to infants with simple MSDK, there were born at an earlier gestation (36.5 vs. 38.8 weeks, P = 0.018). At follow-up, infants with simple MCDK, suffered more episodes of UTI (31% vs. 7%, P = 0.039). Maximum urea (7.2 vs. 4.8, P = 0.041) and creatinine (110 vs. 69, P = 0.045) were significantly higher in infants with complex MCDK. Conclusion: Children with unilateral MCDK suffer long-term morbidities regardless of the associated other renal abnormalities. In addition, given the low incidence of clinically significant VUR and the risks associated with Voiding cystourethrogram (VCUG) screening, routine VCUG is not advocated in patients with MCDK.