title: [Multicystic dysplastic kidney: natural history of the affected and the contralateral kidney compared to the normal and solitary kidney].
abstract: BACKGROUND
  Complications of multicystic dysplastic kidney are rare, but hypertension and malignant transformation represent real danger.
  
  
  METHODS
  In a 10-year period, 94 infants (60 boys, 34 girls) with multicystic dysplastic kidney were diagnosed. The data obtained from these patients were compared to 70 children with solitary kidney of which 36 were newborns. In 80 cases (85%) the diagnosis of multicystic dysplastic kidney was already suspected by prenatal sonography.
  
  
  RESULTS
  Abnormalities of the contralateral kidney were found in 15 of the 94 patients (16%). Complete involution of the multicystic dysplastic kidney was observed in 19, and a decrease in size in 42%. In 37 children (39%) the dysplastic kidney has been removed at the age of about 1 year because of no involution. The length of the contralateral kidney, compared to the normal standard was already significantly larger at birth. In newborn babies with unilateral renal agenesia the solitary kidney was also significantly longer.
  
  
  CONCLUSIONS
  Compensatory hypertrophy of single functioning kidneys occurs in utero both in patients with multicystic dysplastic kidney and in those with unilateral renal agenesia. Based on the results of these and previous studies, early nephrectomy cannot be recommended in the newborn period. Surgery remains an option for patients who have no involution at the time of about 1 year of age.
authors.affiliation: Altalános Orvostudományi Kar, I. Gyermekklinika, Semmelweis Egyetem, Budapest.
authors.forename: Eva
authors.initials: E
authors.lastname: Kis
authors.forename: Tibor
authors.initials: T
authors.lastname: Verebély
authors.forename: Ildikó
authors.initials: I
authors.lastname: Várkonyi
authors.forename: István
authors.initials: I
authors.lastname: Máttyus
mesh_terms: D005260:Female; D006801:Humans; D007223:Infant; D007668:Kidney / Q000473:pathology*; D008297:Male; D021782:Multicystic Dysplastic Kidney / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal