A case of aspartate aminotransferase macroenzyme.

Aspartate aminotransferase (AST) macroenzyme can result in elevated AST activity in patients with no disease. This case report describes a six-year-old boy who presented to his family doctor with a history of chronic constipation and lower back pain. Routine blood tests showed normal creatine kinase activity (CK), normal alanine aminotransferase activity (ALT) but raised AST. The patient was referred to a hospital paediatrician for further investigation of the abnormal AST and back pain. The raised AST was confirmed as the only biochemical abnormality. Further investigation with polyethylene glycol, followed by measurement of AST in the supernatant, showed undetectable enzyme activity. The sample was sent to a specialist laboratory where it was analysed by Sephacryl S300 gel filtration. This procedure confirmed the presence of a high molecular mass form of AST. AST macroenzyme should be considered as a cause of isolated AST increase, which may avoid further costly investigations.

Congenital disseminated neurofibromatosis type 1: a clinical and molecular case report.

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition with a birth incidence of 1/3,500. Around 50% of cases are due to new mutations. The NF1 gene maps to 17q11.2 and encodes neurofibromin. NF1 is a "classical" tumor suppressor gene. Congenital disseminated NF1 is rare with just two cases previously reported. We present a deceased baby with congenital disseminated NF1 in whom we performed molecular studies. A germline mutation (R461X) in exon 10a of the NF1 gene was found. A 2 bp deletion (3508delCA) in codon 1170 of exon 21 was identified in DNA derived from some tumor tissue. Loss of heterozygosity in NF1 and TP53 was observed in other tumor samples. No microsatellite instability was observed in the tumor samples. This is the first report of molecular analysis of the NF1 locus in a patient with disseminated congenital neurofibromatosis. This case had a de novo germline mutation in NF1 and three documented somatic mutations in the NF1 and TP53 genes in tumor specimens.

Risk adjusted mortality of critical illness in a defined geographical region.

AIMS: To evaluate the performance of the Paediatric Risk of Mortality (PRISM) score in a population of UK children and to use this score to examine severity of illness adjusted mortality of critically ill children <16 years old in a defined geographical region. METHODS: Observational study of a defined population of critically ill children (<16 years old) admitted to hospitals in the South West Region between 1 December 1996 and 30 November 1998. RESULTS: Data were collected from 1148 eligible admissions. PRISM was found to perform acceptably in this population. There was no significant difference between the overall number of observed deaths and those predicted by PRISM. Admissions with mortality risk 30% or greater had significantly greater odds ratio for death in general intensive care units compared with the tertiary paediatric intensive care unit. CONCLUSIONS: Children with a high initial risk of mortality based on PRISM score were significantly more likely to survive in a tertiary paediatric intensive care unit than in general intensive care units in this region. However, there was no evidence from this study that admissions with lower mortality risk than 30% had significantly worse mortality in non-tertiary general units than in tertiary paediatric intensive care units.

Positive end expiratory pressure via a portable system in thoracic dystrophy.

The provision of positive end expiratory pressure, via a unique portable system, in the long term management of a child with thoracic dystrophy is reported. The system uses low gas flow enabling a reduction in equipment and simplification of the circuit as compared with a standard continuous positive airways pressure system.

A randomised single blind trial of a combined mumps measles rubella vaccine to evaluate serological response and reactions in the UK population.

Four hundred and twenty children were randomly assigned to receive either mumps measles rubella (MMR) vaccine (207) or measles vaccine (213) in a single blind study, to investigate the reactogenicity and serology of the MMR vaccine. There was no significant difference between the number of children developing symptoms after MMR vaccination to those developing symptoms after measles vaccination. Both vaccines are associated with a rash, temperature and restlessness five to thirteen days after vaccination. The serological response to measles vaccine was similar in both groups with 92-6% seroconverting with MMR, and 96-8% with measles. Seroconvertion against mumps and rubella with the MMR vaccine was 88% and 96% respectively. This study confirms the safety and efficacy of the MMR vaccine in a UK population.