Low grade pelviureteric junction obstruction with normal diuretic renography

We report five patients with normal diuretic renograms who underwent Whitaker pressure perfusion testing. They were found to have normal pressure at low flow rates (2-4 ml/min) and an abnormally elevated pressure at high flow rates (8-10 ml/min). Because of persistent symptoms, two patients underwent surgery, while the other three have been followed up. Our findings indicate that a negative diuretic renogram in a well hydrated patient with good renal function may not rule out low grade obstruction. Renal pelvic perfusion at low flow rates as well as high flow rates is recommended to determine better the function of the pelviureteric junction.     

Interleukin-1 (IL-1) production in a mouse tissue chamber model of inflammation. II. Identification of (tissue) macrophages as the IL-1 producing cells and the effect of anti-inflammatory drugs

We have used our newly described mouse tissue chamber model [1], to investigate the process of IL-1 production in more detail. The inflammatory reaction in the tissue surrounding the implanted chambers was investigated histologically and by using the polymerase chain reaction (PCR). The inflammatory response included influx of leucocytes into the granuloma surrounding the tissue chamber, expression of IL-1 on macrophages present in the inflamed tissue and an increase in the mRNA coding for IL-1 and IL-6 proteins in the granuloma. The effects of three anti-inflammatory or immunosuppressive drugs, prednisolone, indomethacin and cyclosporin A, on IL-1 and PGE₂ production in zymosan andBordetella-pertussis-vaccine (BPV)-challenged tissue chambers were also examined. Oral treatment with prednisolone and cyclosporin A of zymosan-challenged animals showed a dose-dependent reduction of IL-1 concentrations, but no effect of indomethacin. Both prednisolone and indomethacin dose-dependently reduced PGE₂ concentrations to control levels, while cyclosporin A was effective only at the highest dose tested (100 mg/kg/day p.o.). In drug-treated BPV-challenged animals, prednisolone and cyclosporin A also showed a dose-dependent reduction of IL-1, while indomethacin was again ineffective. Prednisolone and indomethacin also dose-dependently reduced the PGE₂ concentrations to control levels, whereas cyclosporin A was effective only at the highest dose tested (100 mg/kg/day p.o.).This model will be useful for investigating the mechanisms controlling the production of IL-1 from the mRNA level to the secretion of mature biologically active protein [1], and in the search for new drugs which could selectively interfere with this process.     

Postmortem molecular analysis of SCN5A defects in sudden infant death syndrome.

CONTEXT: Fatal arrhythmias from occult long QT syndrome may be responsible for some cases of sudden infant death syndrome (SIDS). Because patients who have long QT syndrome with sodium channel gene (SCN5A) defects have an increased frequency of cardiac events during sleep, and a recent case is reported of a sporadic SCN5A mutation in an infant with near SIDS, SCN5A has emerged as the leading candidate ion channel gene for SIDS. OBJECTIVE: To determine the prevalence and functional properties of SCN5A mutations in SIDS. DESIGN, SETTING, AND SUBJECTS: Postmortem molecular analysis of 93 cases of SIDS or undetermined infant death identified by the Medical Examiner's Office of the Arkansas State Crime Laboratory between September 1997 and August 1999. Genomic DNA was extracted from frozen myocardium and subjected to SCN5A mutational analyses. Missense mutations were incorporated into the human heart sodium channel alpha subunit by mutagenesis, transiently transfected into human embryonic kidney cells, and characterized electrophysiologically. MAIN OUTCOME MEASURES: Molecular and functional characterization of SCN5A defects. RESULTS: Two of the 93 cases of SIDS possessed SCN5A mutations: a 6-week-old white male with an A997S missense mutation in exon 17 and a 1-month old white male with an R1826H mutation in exon 28. These 2 distinct mutations occurred in highly conserved regions of the sodium channel and were absent in 400 control patients (800 alleles). Functionally, the A997S and R1826H mutant channels expressed a sodium current characterized by slower decay and a 2- to 3-fold increase in late sodium current. CONCLUSION: Approximately 2% of this prospective, population-based cohort of SIDS cases had an identifiable SCN5A channel defect, suggesting that mutations in cardiac ion channels may provide a lethal arrhythmogenic substrate in some infants at risk for SIDS.     

Polymerase chain reaction and its uses as a diagnostic tool for cardiovascular disease

The polymerase chain reaction (PCR), initially developed approximately a decade ago by Kary Mullis, has revolutionized the basic science and clinical research study of human disease. The beauty and utility of this method derive from its simplicity and automation. PCR amplifies a single copy of DNA sequence into millions of identical copies in a matter of hours, allowing rapid detection of subtle differences in sequence, gene cloning, and mutation analysis, among other uses. In this review, the basic technique of PCR and its applications as a diagnostic tool for cardiovascular disease are discussed.     

Percutaneous gastrostomy tube placement in patients with ventriculoperitoneal shunts

Objective. The purpose of this study is to determine the risk of CNS and/or peritoneal infection in children with ventriculoperitoneal shunts in whom a percutaneous gastrostomy tube is placed. Materials and methods. We placed 205 gastrostomy or gastrojejunostomy tubes from January of 1991 to December 1996. Twenty-three patients (10 boys, 13 girls) had ventriculoperitoneal shunts at the time of placement. All shunts were placed at least 1 month prior to placement of the gastrostomy tube. The patients ranged in age from 8 months to 16 years with a mean age of 6 years, 9 months. Patient weight ranged from 2 kg to 60 kg. All 23 children required long-term nutritional support due to severe neurologic impairment. No prophylactic antibiotics were given prior to the procedure. Of the patients, 21/23 had a 14-F Sacks-Vine gastrostomy tube with a fixed terminal retention device inserted, using percutaneous fluoroscopic antegrade technique. Two of the 23 patients had a Ross 14-F Flexi-flo gastrostomy tube which required a retrograde technique due to a small caliber esophagus in these children. Results. All 23 children had technically successful placements of percutaneous gastrostomy (7) or gastrojejunostomy (16) tubes. Of the children, 21/23 (91 %) had no complications from the procedure. Two of 23 (9 %) patients demonstrated signs of peritonitis after placement of their gastrostomy tubes and subsequently had shunt infections. In both, children CSF culture grew gram-positive cocci. The antegrade technique was used in both children who developed peritonitis. Conclusion. Our study indicates children with ventriculoperitoneal shunts who undergo percutaneous gastrostomy are at greater risk for infection and subsequent shunt malfunction. Therefore, we recommend prophylactic antibiotic therapy to cover for skin and oral flora. Received: 5 August 1997 Accepted: 26 December 1997     

State-of-the art review: Noncompaction cardiomyopathy in pediatric patients

Heart Failure Reviews - Noncompaction cardiomyopathy (NCCM) is a disease characterized by hypertrabeculation, commonly hypothesized due to an arrest in compaction during fetal development. In 2006,...