Non-surgical management of multicystic dysplastic kidney

Abstract

Objectives: To better define the outcome and association of multicystic dysplastic kidney (MCDK) with hypertension, vesico-ureteric reflux (VUR), infection and cancer, as there is no consensus on the management of patients born with MCDK. The risk of cancer has dictated the surgical management of the disease in the past.

Methods: The Medline database was searched for articles published between 1965 and 2006 and written in the English language, and containing the keywords 'multicystic dysplastic kidney'.

Results: The inclusion criteria were met by 105 reports that were subsequently analysed. Of MCDK, 60% regress or involute within 3 years. About 25% of patients will have VUR into the contralateral kidney, of which 90% is grade <or=3. The risk of urinary tract infection appears to be associated with VUR or coexistent abnormalities rather than the MCDK. The risk of hypertension is no greater than that in the general population and nephrectomy is usually not curative. The overall risk of Wilms' tumour developing in a MCDK is <1 in 2000. All reported Wilms' tumours were identified before 4 years of age and 70% presented as a palpable mass.

Conclusions: Published reports support the non-surgical management of MCDK. Common practice has been to remove palpable or growing MCDKs, although these represent a very small fraction of MCDKs. In theory, ultrasonographic surveillance until 4 years old might allow the earlier detection of a Wilms' tumour, and decrease the intensity of chemotherapy and improve prognosis. Previous reports do not prove or disprove this concept, and the appropriate frequency of surveillance is not evident.