To assess ( 1 ) plasma levels of antidiuretic hormone ( ADH ) and brain natriuretic peptide ( BNP ) and urinary levels of electrolytes in children with sleep disordered breathing ( SDB ) , with or without nocturnal enuresis ( NE ) , and ( 2 ) the effect of adenotonsillectomy ( T&A ) on urinary electrolytes and the secretion of ADH and BNP in children with NE and SDB .