Dena M. Selby

Bladder distention and pyelectasis in the male fetus: causes, comparisons, and contrasts.

The objective of this paper was to determine if prenatal sonographic findings can accurately differentiate between the causes of bladder distention and pyelectasis in the male fetus. Twenty‐one cases were evaluated for the presence of oligohydramnios, posterior urethral dilation, bladder wall thickening, urachal patency, cortical thinning, cortical cysts, and increased renal echogenicity. Postnatal diagnosis included posterior urethral valves (10 cases), prune belly syndrome (four cases), vesicoureteral reflux (four cases), left ureterovesical junction obstruction (one case), and nonrefluxing, nonobstructive megacystis‐megaureter (two cases). Oligohydramnios was present in eight of 10 cases of posterior urethral valves and in one of four cases of prune belly syndrome. A dilated posterior urethra was noted in seven of 10 cases of posterior urethral valves and transiently in two of four cases of prune belly syndrome. Bladder wall thickening developed in all cases of posterior urethral valves and was noted in two of four patients with prune belly syndrome. A patent urachus likewise was identified in two of four cases of prune belly syndrome. The presence of oligohydramnios, progressive bladder wall thickening, and dilated posterior urethra was most suggestive of posterior urethral valves, whereas the presence of a patent urachus was most suggestive of prune belly syndrome. The presence of pyelectasis and megacystis without additional amniotic fluid, bladder, urethral, or renal abnormalities was most suggestive of vesicoureteral reflux, ureterovesical junction obstruction, or nonrefluxing, nonobstructive megacystis‐megaureter. Owing to the overlap and evolution of these findings, close follow‐up evaluation is recommended.

Atypical hemolytic uremic syndrome in human immunodeficiency virus-1-infected children

Abstract. We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters, both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains unknown and the role of HIV infection in its pathogenesis, although possible, is unclear.

AMEBIC OSTEOMYELITIS IN a CHILD WITH ACQUIRED IMMUNODEFICIENCY SYNDROME: A Case Report

Disseminated Acanthamoeba infection has been described in immunocompromised or debilitated patients. The usual sites of involvement are skin, sinus, and brain. Sporadic reports of Acanthamoeba infection in patients infected with the human immunodeficiency virus are present in recent literature, predominantly in adults, and one case involving an 8-year-old child. We describe a case of amebic osteomyelitis, seen in a 6-year-old child with vertically acquired human immunodeficiency virus and a 6-month history of cutaneous Acanthamoeba infection.

Cystic sonographic appearance of extralobar pulmonary sequestration

A cystic fetal chest mass showing spontaneous improvement in utero is described. This mass was shown to be an extralobar pulmonary sequestration with associated cystic adenomatoid malformation type 2.

Different vascular patterns of medulloblastoma and supratentorial primitive neuroectodermal tumors.

Astrocytoma vasculature patterns differ according to histological grade of malignancy with glioblastoma multiforme (WHO grade IV) showing most extensive endothelial proliferation. Here, we determined whether the vascular patterns of medulloblastoma and supratentorial primitive neuroectodermal tumors (PNETs), which can be hardly distinguished histopathologically, differ. We evaluated the spatial organization of vessels in medulloblastomas and PNETs using antibodies to von Willebrand factor (vWF) and CD34. Medulloblastoma capillaries showed slight endothelial cell hyperplasia. Microvessels sprouted from the capillaries and formed glomeruloid clusters. There were areas with chains of unopposed endothelial cells (3–10 cells). Supratentorial PNETs had highly branched capillaries with extensive endothelial cell hyperplasia. Glomeruloid arrays of microvessels extended from the capillaries. Small fragments of endothelial tubes were scattered throughout the tumor. Therefore, medulloblastomas and supratentorial PNETs showed different spatial organization of tumor vessels which can be used for differentiation of each tumor entity. These vascular patterns may reflect different tumor derived angiogenic stimuli.

Colonic diverticulitis causing partial bowel obstruction in a child with cystic fibrosis

Abstract Children and adolescents with cystic fibrosis (CF) may manifest bowel pathology with resulting bowel obstruction. Recognized causes of bowel obstruction in CF patients include meconium ileus, intussusception, distal intestinal obstruction syndrome and postoperative adhesions. Additionally, the development of colonic strictures in children with CF has recently been described. We report an unusual cause of partial obstruction of the ascending colon in a child with CF due to pathologically proven diverticulitis.

Plexiform neurofibroma of the penis in a child.

We report a case of a child with the stigmata of von Recklinghausens disease and a plexiform neurofibroma arising from the penile shaft.

Expression of renal and vascular angiotensin II receptor subtypes in children.

Abstract Angiotensin II (Ang II) AT1 receptors modulate most of the known physiological functions of Ang II in the kidney and cardiovascular structures. In contrast, the physiological role of AT2 receptors, which are abundantly expressed in fetal tissues, is not clearly defined. The changes that occur in the expression and distribution of AT2 receptors in the kidney and arteries during the first 2 years of life have not been studied. We have localized and characterized the expression of Ang II receptor subtypes, AT1 and AT2, in the kidney, interlobular arteries, thoracic aorta, and middle cerebral artery, in children during their first 2 years of life, using quantitative autoradiography. Renal glomeruli and middle cerebral arteries expressed exclusively AT1 receptors. In contrast, more than 80% of the Ang II receptors expressed in thoracic aorta and interlobular arteries belonged to the AT2 subtype. These findings demonstrate that the expression of Ang II receptor subtypes in different vascular structures in young children varies according to the tissue.