Beverly B. Dahms

Paravertebral malignant rhabdoid tumor in infancy. In vitro studies of a familial tumor.

Two female siblings died within three months after presenting with paravertebral tumors in the first year of life. The pathology of the two tumors was identical and characteristic of a malignant rhabdoid tumor. There were no identifiable tumor patterns within the kindred which have been associated with any hereditary cancer or precancer syndromes. Fibroblasts were cultured from skin biopsies obtained from the second patient and both parents. Assays of growth kinetics associated with cellular transformation revealed that fibroblasts from the affected sibling can be distinguished from those of the parents and age‐matched controls by increased in vitro occurrence of tetraploidy. Such evidence suggests that increased in vitro tetraploidy occurring spontaneously in cultured fibroblasts is an expression of a cancer‐prone gene. Increased in vitro tetraploidy has previously been demonstrated in some kindreds with heritable colon cancer syndromes, and may extend our understanding of the genetic etiology of some childhood cancers. Cancer 52:290‐296, 1983.

Malassezia pulmonary vasculitis in an infant on long-term intralipid therapy.

MALASSEZIA FURFUR (formerly Pityrosporum orbiculare) is a fungus of low pathogenicity known to cause diseases of the skin. Members of the genus malassezia lack the ability to synthesize medium-chai...

Malignant rhabdoid tumor of the heart in an infant

A 6‐month‐old infant presenting with pericardial effusion was found to have a malignant rhabdoid tumor of the heart. As visualized by two‐dimensional echocardiography and subsequently by contrast‐enhanced computerized axial tomographic scanning, the tumor arose from the left ventricular free wall and grew into the pericardial space. Despite two courses of single‐agent chemotherapy with doxorubicin, the child died 3 months later. This is the first reported case of malignant rhabdoid tumor of the heart, and the fifth case of a primary cardiac malignancy in an infant.

Renal histological changes secondary to ureteropelvic junction obstruction.

The treatment of children with apparent ureteropelvic junction obstruction is controversial. In an asymptomatic infant or child the decision to recommend pyeloplasty usually is based on interpretation of the renal scan. We retrospectively analyzed the renal biopsy obtained during pyeloplasty in 55 children. Histological changes were compared to the differential renal function revealed on the preoperative renal scan. Histological changes were graded on a scale of I to V; I--normal, II--mild dilatation of the collecting tubules or Bowmans space and III to V--progressively severe changes of obstructive uropathy, including reduced glomerular number, glomerular hyalinization, cortical cysts and interstitial inflammation. Patient age ranged from 4 days to 19 years (mean 4.8 years). Mean differential function according to histological grade was I--49%, II--43%, III--42%, IV--30% and V--25%. Of 33 patients with a differential function of 40% or greater 26 (79%) had a grade I or II biopsy, while 21% had a more significant alteration in renal histology. In contrast when the differential function was less than 40% 6 of 18 patients (33%) had grade I or II disease on biopsy. In conclusion, in approximately 25% of children with ureteropelvic junction obstruction there is a disparity between preoperative differential renal function computed during diuretic renography and renal biopsy.

Reflux esophagitis: sequelae and differential diagnosis in infants and children including eosinophilic esophagitis.

Gastroesophageal reflux disease (GERD) is a common condition in infants and children and has many clinical mimics. Most pediatric pathology departments process many mucosal biopsies from the proximal gastrointestinal tract to evaluate the presence or absence of reflux esophagitis. Since this subject was last reviewed in the 1997 edition of Perspectives in Pediatric Pathology devoted to gastrointestinal diseases in children (Dahms BB. Reflux esophagitis and sequelae in infants and children. In: Dahms BB, Qualman SJ, eds. Gastrointestinal Disease. Perspectives in Pediatric Pathology, vol. 20. Basel: Karger, 1997;14–34), progress in the field has allowed recognition of additional presenting symptoms and treatments of GERD. Histologic criteria for diagnosing reflux esophagitis have not changed. However, the entity of eosinophilic esophagitis has emerged since 1997 and has been defined well enough to allow it to be distinguished from reflux esophagitis, with which it was probably previously confused. Refinements (though not simplification!) in the definition of Barrett esophagus are still in evolution. This review will summarize these newer concepts and briefly review the standards of diagnosis of reflux esophagitis.

Systemic Malassezia furfur infections in patients receiving intralipid therapy

Systemic infection with Malassezia furfur was first reported in 1981 as a specific complication of Intralipid therapy in a neonate. Six additional patients, including three older than 16 years of age, were identified subsequently. All had received prolonged Intralipid infusion through central venous catheters. Pulmonary infection was documented in tissue in three cases, the clinical presentation was characterized by pulmonary infiltrates, fever, and, in the infants, thrombocytopenia. Two subgroups of patients appear to be at the greatest risk for Malassezia infection: neonates with cardiopulmonary disease and adults with severe gastrointestinal disease and immunosuppression. The documentation of pulmonary arterial lipid deposits in vessels that had been infiltrated by Malassezia organisms and the observation of organisms in small pulmonary thromboemboli suggest that these lipophilic and lipid-dependent organisms are introduced into the bloodstream from venous catheters and require high lipid concentrations to proliferate in tissue.

Pulmonary arterial lipid deposit in newborn infants receiving intravenous lipid infusion

Three newborn infants are described with a distinctive pulmonary arterial lipid lesion, characterized by a wide foamy layer of intima partially occluding the lumen of small muscular pulmonary arteries. Lipid stains indicated lipid infiltration of the walls of these arteries, involving not only the intimal layer, but media and adventitia as well. All three infants had received intravenous lipid infusions. All three infants also had histologic evidence of pulmonary hypertension, one on the basis of chronic lung disease (BPD) and two on the basis of congenital heart disease. A retrospective autopsy study of long-term neonatal ICU dwellers receiving such infusions revealed two additional patients with lipid deposits in pulmonary arterial walls. It is speculated that the pulmonary arterial lipid deposits were derived from the lipid infusions and were dependent on antecedent or concurrent vascular damage from pulmonary hypertension.

Severe perinatal liver disease associated with fetal thrombotic vasculopathy.

Three neonates with fetal thrombotic vasculopathy in the placenta and severe neonatal liver disease are described. Symptoms included a bleeding disorder on the first day of life, followed by direct hyperbilirubinemia and elevated liver transaminases. All patients also had evidence of thrombosis outside the placenta, including cerebral infarct in two infants and thrombosis of the inferior vena cava in one infant. Liver disease was demonstrated to be thrombotic in one infant who died with Budd-Chiari syndrome. Two infants survived and had liver biopsy with cholestasis, bile duct proliferation, and portal fibrosis demonstrated at 4 weeks and 11 weeks of age, respectively. The etiology of thrombosis is unknown, though in one patient an excessively long and coiled umbilical cord may be implicated. The prenatal onset of thrombosis suggests an inherited or acquired thrombophilic state. In cases of enigmatic neonatal liver disease, an association with thrombosis should be considered and thrombi sought in placenta, umbilical cord, major blood vessels, and other organs. Evaluation for a hypercoagulable state is also suggested.

Nesidioblastosis and other islet cell abnormalities in hyperinsulinemic hypoglycemia of childhood

The histologic findings are described in 16 subtotal pancreatectomies performed in patients with hyperinsulinemic hypoglycemia over a 17 year period. All patients had nesidioblastosis, defined as the presence of small packets of two to 25 islet cells scattered throughout acinar tissue and separate from islets of Langerhans. The proliferating islet cells were a mixture of beta, alpha, and delta cells. Two histologic subgroups were apparent: Group I patients had diffuse hyperplasia of the islets of Langerhans as well as nesidioblastosis, and group II patients had more subtle nesidioblastosis alone. The patients in groups I and II were remarkably age segregated. All but one of the group I patients were eight months old or younger. Group II patients ranged in age from three to 15 years. The incidence of nesidioblastosis in the patients undergoing pancreatectomy was higher than the incidence in a group of age matched autopsy controls.

Pulmonary air cysts in cystic fibrosis: Relation of pathologic features to radiologic findings and history of pneumothorax**

One lung obtained from each of 21 consecutive autopsies in adolescents and young adults with cystic fibrosis was studied prospectively by macroscopic morphometry and light microscopy to determine the prevalence, morphology, and radiographic appearance of subpleural air cysts, which potentially contribute to spontaneous pneumothorax. In 15 lungs, 41 cysts of three anatomic types were identified: bronchiectatic cysts (23), interstitial cysts (13), and emphysematous bullae (5). All cysts were significantly more numerous in the upper lobe. Bronchiectatic cysts had the largest mean diameter, occupied from less than 1 per cent to 47.7 per cent of upper lobe volume in nine patients, and produced large multiloculated hyperlucencies on chest radiographs in five cases. All six lungs with prior pneumothorax contained at least one cyst, but no significant difference was found in the type or proportion of lung volume occupied by cysts between lungs with and without pneumothorax. Patients with large cysts had significantly lower chest radiograph scores, but there was no correlation between the proportion of lung volume occupied by cysts and patient age or duration of either symptomatic lung disease or colonization by bacteria. On chest radiographs only bronchiectatic cysts with conglomerate diameters of greater than 3 cm were visible. Smaller lesions could not be separated from ring shadows produced by bronchiectasis.