Fetal rhabdomyomatous nephroblastoma-a variant of Wilms' tumor.

The fetal rhabdomyomatous nephroblastoma is considered to be a predominantly monophasic mesenchymal variant of Wilms' tumor, which has not been seen in patients older than four years. It acts less aggressively than a Wilms tumor despite its much larger size. Its better prognosis appears to be related to either the absence of or the insignificant amounts of neoplastic epithelium. The bilaterality of this tumor in one-third of the cases, however, may negatively affect the overall prognosis, because complete resection may be impossible or because renal failure ensues.

The radiologic and pathologic spectrum of the prune belly syndrome. The importance of urethral obstruction in prognosis.

The definition, history, and clinical presentation of the prune belly syndrome are outlined. Review of autopsy material and survivors reveal three groups of patients, and the author describes the choices of management available for both groups. Highlighted is the role of the radiologist.

Peliosis hepatis in a child.

Peliosis hepatis, which has previously only been reported in adults, occurred in a chronically ill 11-year-old boy with cystic fibrosis. As in cases in adults, chronic illness, long-term anabolic steroid therapy, and right ventricular congestive failure may well have been the causative factors in this case. Histologically, the phlebectatic and parenchymal types, which were presumed to be separate, were found conjointly in this case. This is compatible with its origin from severe right ventricular congestive failure. The rarity of peliosis, however, indicates that one or more as yet unknown factors might be operative in its development.

Fatal desquamative interstitial pneumonia in an infant: case report with transmission and scanning electron microscopical studies.

Desquamative interstitial pneumonia in a young infant followed a rapidly fatal course and developed morphologic features of honey-combing, giant cell pneumonia, and pulmonary alveolar proteinosis. The rapid and fatal progression of the disease in spite of steroid therapy and the polymorphous histologic appearance of the lungs at autopsy raise doubt that the disease is a relatively benign and uniform entity and invalidate the classical initial histologic features as prognostic indicators.

Extraskeletal Ewing sarcoma. An ultrastructural study.

Soft tissue tumors with the characteristics of Ewing sarcoma of bone have thus far only been studied by light microscopy. A pelvic tumor of this type in a 13-year-old girl was examined by electron microscopy. Comparison of its ultrastructural features with those of reported cases of bony Ewing sarcoma reveal much similarity. It is believed that they are probably identical and that the tumor cells are of immature mesenchymal type. However, their site of origin and the direction of their potential differentiation remain obscure.

Epidermoid cysts of the liver.

To the four recorded cases of epidermoid cysts of the liver are added two cases recently seen in children. One was in a 4-yr-old girl and associated with biliary cirrhosis. The other was in a 5-mo-old boy. The former was treated by roux-en-y cystjejunostomy, the latter by enucleation. The origin of these cysts is unknown. One theory suggests derivation from accessory foregut buds. Because of their malignant potential, treatment should be by excision. Where this is impossible, roux-en-y cystjejunostomy offers satisfactory palliation.

Effects of total parenteral nutrition and semi-starvation on the liver of beagle puppies.

The effects on hepatic growth of fat-free TPN and semistarvation have been studied in newborn beagle puppies. Our data indicate that liver growth during TPN is characterized by normal deposition of protein and minerals, with increased glycogen and decreased lipid content. While the lipid pattern of TPN livers is normal, the phospholipid fraction contains an abnormal fatty acid pattern, consistent with the development of essential fatty acid deficiency. The exact physiologic significance of this is unknown, but it is tempting to speculate that changes in integrity of the hepatic cell membrane as a result of this abnormal fatty acid pattern might account for some of the clinical abnormalities of hepatic function during TPN.

Calcific thrombi of the inferior vena cava in infants and children.

Calcified caval thrombus should be considered in any infant or child where calcifications are noted in the high right retroperitoneal area on plain x-rays of the abdomen. Although typically bullet-shaped in configuration, the calcium distribution in the neonate may be atypical or incompletely developed, suggesting neuroblastoma. Definitive diagnosis can be made by inferior vena cavagram. As no deaths or complications have been attributed to the lesion in the cases thus far reported, no specific treatment is recommended.

Fetal mesenchymal hamartoma of kidney. A tumor of secondary mesenchyme.

The ultrastructure of a fetal mesenchymal hamartoma of the kidney shows undifferentiated mesenchymal cells, whose morphological characteristics conform to those of secondary mesenchyme. In contrast to primary mesenchyme or mesoblast, which may form epithelial structures, secondary mesenchyme is incapable of doing so. While Wilms' tumor may be considered a tumor of mesoblast, the fetal mesenchymal hamartoma is believed to originate from secondary mesenchyme or some of its more mature derivatives.

Asplenia syndrome in conjoined twins: a case report.

Incomplete fission of the primordial cell mass is generally believed to be the cause of conjoined twinning. It may also explain the tendency towards increased symmetry in these twins. We report a case of the rostral duplication type of conjoined twins with an absence of symmetry; one twin had the asplenia syndrome, whereas the other twin was normal. Local environmental factors acting upon the organ anlage may explain the asymmetric development in these conjoined twins.

Distribution and development of angiotensin converting enzyme in the fetal and newborn rabbit. An immunofluorescence study.

The distribution and development of angiotensin converting enzyme (EC 3.4.15.1) were studied in fetal and newborn rabbits, using fixed tissues embedded in paraffin and stained with a fluorescein-conjugated antibody specific for the enzyme. The enzyme was found at the luminal plasma membrane of endothelial cells from the second third of gestation to the neonatal period. In addition, two types of epithelial cells also contained the enzyme, renal tubular and intestinal. The vascular enzyme may play a role in the regulation of its vasoactive peptide substrates, angiotensin and bradykinin, at term.

Fibrous histiocytoma simulating congenital fibromatosis: a light-, electron microscopic and tissue culture study.

The unusual occurrence of a fibrous histiocytoma of subcutaneous soft tissues, bones, and viscera is described in a newborn infant. The clinical and radiologic picture simulated a congenital fibromatosis, but histologic, electronmicroscopic and tissue culture studies indicated a malignant tumor with a bimodal cell population resembling immature fibroblasts and histiocytes. Although less mature and more uniform, it essentially parallels the findings in the adult malignant fibrous histiocytomas.

Protein-losing enteropathy in prolonged post-ischemic ileitis.

A 10-year-old boy developed internal herniation of the small intestine associated with significant ischemia, which was reduced without resection. Severe diarrhea, hypoalbuminemia, and lymphopenia ensued while he was receiving total parenteral nutrition. Resolution of symptoms occurred only after resection of an area of ileum, which revealed persistent inflammation and atrophy. Postischemic epithelial cell regeneration of the intestine is discussed in light of this patient's protein-losing enteropathy.