Loss of living donor renal allograft survival advantage in children with focal segmental glomerulosclerosis.

BACKGROUND: Because of concerns of increased risk of graft loss with recurrent disease, living donor (LD) transplantation in children with focal segmental glomerulosclerosis (FSGS) has been controversial. METHODS: The North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) database from January 1987 to January 2000 was examined to determine differences in demographics, treatment, and outcomes in children with FSGS compared with other renal diseases. RESULTS: Data on 6484 children, 752 (11.6%) with FSGS, demonstrated that FSGS patients were more likely to be older and black, and were less likely to receive either pre-emptive or LD transplant (P < 0.001). No differences existed in human lymphocyte antigen (HLA) matching or immunosuppression regimens. Acute tubular necrosis occurred in more FSGS patients following LD (11.8 vs. 4.6%) or cadaveric (CD; 27.9 vs. 16.3%) transplants (P < 0.001). Graft survival was worse for LD FSGS patients (5 years 69%) compared with no FSGS (82%, P < 0.001) and was not significantly different than CD graft survival in the FSGS (60%) and No FSGS groups (67%). The LD to CD ratios of relative risk of graft failure were higher in FSGS patients (test for interaction, P = 0.01). Recurrence of original disease was the only cause of graft failure that differed between groups (P < 0.001). A greater percentage of LD FSGS graft failures was attributed to recurrence (P = 0.06). CONCLUSIONS: The impact of FSGS on graft survival in children is greatest in LD transplants, resulting in loss of expected LD graft survival advantage. The rationale for LD grafts in children with FSGS should be based on factors other than better outcomes typically associated with LD transplantation.

Homonucleotide expansion and contraction mutations of PAX2 and inclusion of Chiari 1 malformation as part of renal-coloboma syndrome.

Renal-Coloboma syndrome, an autosomal dominant disorder characterized by colobomatous eye defects, vesicoureteral reflux, and abnormal kidneys, results from mutations in PAX2. The purpose of this study was to identify mutations in PAX2 and understand the associated patient phenotypes. We report a severely affected girl and a mildly affected mother and daughter, all of whom have PAX2 homoguanine tract (7 G) missense mutations. The mother and daughter have optic nerve colobomas and the daughter has vesicoureteral reflux. The severely affected girl developed renal failure and has bilateral colobomatous eye defects. Additionally, this girl developed hydrocephalus associated with platybasia and a Chiari 1 malformation. We examined genomic DNA from these individuals by SSCP and sequencing. The mother and daughter had a novel mutation: a contraction in a string of 7 G's to 6 G's in one allele of PAX2, leading to a premature stop codon two amino acids downstream. The severely affected girl had an expansion to 8 G's, leading to a premature stop codon 27 amino acids downstream. The 8 G expansion has been found in other patients without brain anomalies and has occurred spontaneously in a mouse model, PAX2(1Neu). We expand the known phenotype associated with mutations in PAX2 to include brain malformations. The homoguanine tract in PAX2 is a hot spot for spontaneous expansion or contraction mutations and demonstrates the importance of homonucleotide tract mutations in human malformation syndromes.

Aortic dissection in young patients with chronic hypertension.

We describe four patients aged 14 to 21 years who developed acute aortic dissection. In three of the four patients, the course was fatal, despite aggressive medical and surgical intervention. All four patients had sustained systemic hypertension related to chronic renal insufficiency. The patients had no other identifiable risk factors for aortic dissection, including congenital cardiovascular disease, advanced atherosclerosis, vasculitis, trauma, pregnancy, or family history of aortic dissection. Although aortic dissection is rare in individuals younger than 40 years of age, young patients with sustained systemic hypertension are at increased risk for this serious and often fatal condition. Physicians must be aware of this rare complication of hypertension and consider aortic dissection in the differential diagnosis of unusual chest, abdominal, and back pain in hypertensive children, adolescents, and young adults.

Charcoal hemoperfusion in a child with vancomycin overdose and chronic renal failure.

A 14-month-old girl with chronic renal insufficiency received a massive overdose of vancomycin, resulting in worsened renal failure and ototoxicity. We report the use of combined charcoal hemoperfusion and dialysis to accelerate vancomycin removal in this patient.

Autoimmune hemolytic anemia after Kawasaki disease in a child.

A 2-year-old male presented with upper respiratory tract infection symptoms, continuous high fever, extensive truncal rash with desquamation, lymphadenopathy, subconjunctival hemorrhage, and oral stomatitis. He was diagnosed with Kawasaki disease and did well on aspirin. Approximately 8 weeks after initial presentation he had evidence of severe immune hemolysis. At that time a direct antiglobulin test was microscopically positive; it became strongly positive (3 + IgG, w + C3) 2 weeks later. The serology was unusual in that a warm IgG autoantibody and a low titer high thermal range cold antibody of unusual specificity (anti-Ena or anti-Pr) were present. We were uncertain as to which antibody caused the hemolysis, or whether they worked synergistically. The hemolysis resolved following treatment with high dose prednisone.

New onset childhood seizures. Emergency department experience.

Fifty-six cases of new onset seizures evaluated in a pediatric emergency department (ED) during a one-year period were assessed retrospectively for efficiency of diagnosis and workup. The majority of patients (69%) were less than two years of age. Based on etiology, the most common seizure type was febrile (71%) followed by idiopathic (21%) and symptomatic (7%). Significant laboratory abnormalities were found in four (7%) patients; two had hyponatremia, one carbamazepine overdose and one bacterial meningitis. Screening laboratory tests including brain CT scans were generally not helpful. A thorough history including specific details regarding the seizure and a complete physical examination should eliminate the need for major laboratory and radiologic workup in the emergency department.