Multinodular Hyperplastic Pannephric Nephroblastomatosis with Tubular Differentiation: A New Morphologic Variant

Abstract

We report a case of bilateral nephromegaly detected prenatally with oligohydramnios. Delivered at 35 weeks, this black male infant rapidly developed renal failure, requiring dialysis. He lived 3 1/2 months. The kidneys were three times normal size and diffusely multinodular, with hypoplastic calyces, no corticomedullary demarcation, and no pyramids. Histologically, they revealed hyperplastic embryonal rests composed of tubules and ducts with prominent branching. The nodular rests were intermixed with areas of mature parenchyma, which showed prominent oxalosis. By flow cytometry, rests were diploid, with an S-phase fraction of 25.9%. The proliferation of embryonal collecting system analogs is attributed to excessively rapid and prolonged branching of the ureteric bud, dating from the fourth gestational month or earlier. This unique case may represent a new morphologic variant of universal nephroblastomatosis.

Bilateral Renal Dysplasia, Nephroblastomatosis, and Bronchial Stenosis. A New Syndrome?

“…The case published in 1994 contained a more classical renal blastemal comprising confluent perilobar nephrogenic rests with an associated renal dysplasia. On the other hand, the 1996 case had tubular differentiation resembling the epithelial component of some Wilms tumors [10,11]. Lastly, a more recent report on two siblings with bilateral nephromegaly and autopsy proven universal NB, suggested an autosomal recessive mode of inheritance [12].…”

“…The autopsy revealed generalized visceromegaly, islet cell hyperplasia and hypertrophy, and nephroblastomatosis. Several small series and single case reports of NB detected at autopsy have followed over the course of the next three decades [8][9][10][11]. A series by De Chadarevian et al described four children with nephromegaly detected on physical examination and confirmed by imaging.…”

Bilateral Panlobar Nephroblasyomatosis and Bladder Neck Polyp in a Newborn

“…Universal (panlobar) type indicates total replacement of the renal lobe by nephrogenic tissue 1 . Massive renal involvement and pulmonary hypoplasia due to compression of enlarged kidneys make this extremely uncommon disease usually incompatible with life 4 .…”