Xeroderma pigmentosa: three new cases with an in depth review of the genetic and clinical characteristics of the disease.

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by hypersensitivity of the skin and eyes to UV-radiation as a result of a defect in one of eight genes. Seven genes (XPA-XPG) have a defect in Nucletoide Excision Repair (NER), while the eighth gene XPV has a defect in polymerase η, which is responsible for replication of UV-damaged DNA to produce corrected daughter strands. We present the varied clinical courses of three African-American female patients with XP.

Pathogenic Yersinia DNA in intestinal specimens of pediatric patients with Crohn's disease.

Studies indicate a close relationship between Yersinia and Crohn's disease in adults. Our study tested 77 colonic specimens from children with Crohn's disease for the presence of Yersinia DNA using a validated polymerase chain reaction (PCR) assay. Control cases included specimens from 45 ulcerative colitis patients and 10 appendicitis patients.

Hepatic pulmonary fusion: two cases with diaphragmatic hernia and one case with Pentalogy of Cantrell.

Hepatic pulmonary fusion (HPF) is characterized by a fibrous connection between the liver and lung tissue. We present two cases of hepatic pulmonary fusion diagnosed with right diaphragmatic hernia and a third case with Pentalogy of Cantrell exhibiting complete agenesis of the diaphragm and finger-like projections of liver adhered to the right lung. It has been proposed that this anomaly is secondary to developmental failure of the mesoderm between days 14-18 after conception and is attributed to diaphragmatic maldevelopment.

Pneumatosis intestinalis in pediatric hematopoietic stem cell transplantation patients: an uncommon complication.

Hematopoietic stem cell transplantation (HSCT) causes many complications including the development of graft-versus-host disease (GVHD). Pneumatosis intestinalis (PI), a rare side affect in patients with post-HSCT GVHD, is uncommonly seen in non-neonatal patients. In neonates, surgical intervention is common, yet in non-neonatal patients, medical management is advisable.

Nephrogenic rest within a lipomyelomeningocele in a patient with unilateral renal agenesis.

Nephrogenic rests (NR) are foci of embryonal renal tissue that persist beyond the normal period of renal morphogenesis. They are commonly found in kidneys bearing Wilms tumor but may also rarely occur in different locations. Nephrogenic rests have been reported in the lumbosacral area in a total of nine cases, including our case.

Fibrocartilaginous mesenchymoma, a unique osseous lesion: case report with review of the literature.

Fibrocartilaginous mesenchymoma is a rare osseous tumor that primarily arises in the long bones of children and adolescents. This lesion can grow quickly and reach a considerable size, despite its benign nature. It has proved challenging to diagnose and can be mistaken for a spectrum of benign and malignant bone tumors.