Intestinal injury and endotoxemia in children undergoing surgery for congenital heart disease.

RATIONALE: Children with congenital heart disease are at risk of gut barrier dysfunction and translocation of gut bacterial antigens into the bloodstream. This may contribute to inflammatory activation and organ dysfunction postoperatively. OBJECTIVES: To investigate the role of intestinal injury and endotoxemia in the pathogenesis of organ dysfunction after surgery for congenital heart disease. METHODS: We analyzed blood levels of intestinal fatty acid binding protein and endotoxin (endotoxin activity assay) alongside global transcriptomic profiling and assays of monocyte endotoxin receptor expression in children undergoing surgery for congenital heart disease. MEASUREMENTS AND MAIN RESULTS: Levels of intestinal fatty acid binding protein and endotoxin were greater in children with duct-dependent cardiac lesions. Endotoxemia was associated with severity of vital organ dysfunction and intensive care stay. We identified activation of pathogen-sensing, antigen-processing, and immune-suppressing pathways at the genomic level postoperatively and down-regulation of pathogen-sensing receptors on circulating immune cells. CONCLUSIONS: Children undergoing surgery for congenital heart disease are at increased risk of intestinal mucosal injury and endotoxemia. Endotoxin activity correlates with a number of outcome variables in this population, and may be used to guide the use of gut-protective strategies.

Acute combined central and peripheral nervous system demyelination in children.

Reports of acute combined central and peripheral nervous system acquired inflammatory demyelination are rare in children. This study aimed to (1) define the clinical features and prognoses of patients with this entity; and (2) compare these patients with children presenting isolated acute central or peripheral nervous system demyelination. A retrospective chart review of 523 children with central or peripheral nervous system demyelination hospitalized between 1993-2006 was undertaken. Among these, 93 fulfilled criteria (clinical features and positive magnetic resonance imaging or electromyography/nerve conduction studies) for either acute central (n = 37; 39.8%) or peripheral (n = 43; 46%) nervous system demyelination, or a combination of the two (n = 13; 14%). Significant differences between groups were evident for age (median, 10 versus 7 versus 11 years, respectively; P = 0.047), admission to pediatric intensive care unit (8% versus 30% versus 58%, respectively; P = 0.001), length of hospital stay (median, 8 versus 9 versus 29 days, respectively; P < 0.001), treatment with steroids (52% versus 7% versus 75%, respectively; P < 0.001) and immunoglobulins (11% versus 81% versus 75%, respectively; P < 0.001), and poor evolution (3% versus 12% versus 54%, respectively; P = 0.002). This entity in children is not rare, and has a poorer outcome than isolated central or peripheral nervous system demyelination. Assessment is needed for a better understanding of risk factors, etiologies, management, and prognosis.

Critical illness polyneuromyopathy in a child with severe demyelinating myelitis.

We report a child presenting with severe demyelinating myelitis complicated with critical illness polyneuropathy. This previously healthy 8-month-old boy presented with acute superior limb weakness, absent tendon reflexes, and respiratory failure. Spinal magnetic resonance imaging showed an extensive cervical demyelinating lesion. Spinal cord trauma was suspected and high doses of dexamethasone were administered. Electromyography and nerve conduction studies showed absence of compound muscle action potentials and sural nerve sensory action potential, which was suggestive of a severe Guillain-Barré syndrome. However, intravenous immunoglobulins did not induce any improvement. Afterward, sural nerve biopsy showed a mild neuropathy, but muscle biopsy revealed abnormalities compatible with severe critical illness myopathy. After 5 months of evolution without improvement, the patient died following withdrawal of life support therapy. This case highlights the possible occurrence of critical illness polyneuromyopathy when treatment with corticosteroids are used in patients with acute demyelinating myelitis.