Am J Med Genet Suppl 1987;3:395-410

Pathology of renal and hepatic anomalies in Meckel syndrome

Blankenberg TA, Ruebner BH, Ellis WG, Bernstein J, Dimmick JE
Department of Pathology, University of California, Davis Medical Center,
Sacramento 95817

Abstract
We describe 9 cases of Meckel syndrome (dysencephalia splanchnocystica), ranging
in gestational age from 17 to 39 weeks. Five were liveborn, and the longest
survival was 30 hours. Six of the 9 had all 3 elements of the classically
defined triad, namely occipital encephalocele, renal cystic dysplasia, and
postaxial polydactyly. The remaining 3 cases had only 2 elements of the triad.
The renal abnormalities in the 9 cases resembled one another closely, varying
only slightly in severity. They consisted of renal cystic dysplasia with
different degrees of nephronic differentiation. The 8 available livers all
contained intrahepatic bile duct anomalies. Seven of them had the classic
"ductal plate malformation," as defined by Jorgensen [1977]; the remaining case
had a less severe form of this malformation. The livers of the Meckel syndrome
fetuses were compared to those of age-matched control fetuses, and it was
concluded that the hepatic abnormality represents an arrested development of the
intrahepatic biliary system at the stage of biliary cylinders with varying
degrees of reactive bile duct proliferation, bile duct dilatation, portal
fibrosis, and portal fibrous vascular obliteration superimposed on the arrested
pattern. The case showing the least severe hepatic lesion also had the least
severe renal lesion. The anomalies that were present are listed. The
relationship of the different lesions to each other is briefly discussed. It was
concluded that the hepatic lesion appears to be a consistent manifestation in
Meckel syndrome and is of diagnostic value as the renal lesion has previously
been shown to be