[1] UNIV LAUSANNE,DEPT CLIN CHEM,CH-1011 LAUSANNE,SWITZERLAND
[2] REG HOSP SION,DEPT PAEDIAT,SION,SWITZERLAND
[3] CHILDRENS HOSP PHILADELPHIA,PHILADELPHIA,PA
[4] UNIV BERN,DEPT CLIN CHEM,CH-3000 BERN,SWITZERLAND
[5] UNIV BERN,DEPT PAEDIAT,CH-3000 BERN,SWITZERLAND
[6] HOSP VALAIS,INST PATHOL,VALAIS,SWITZERLAND
[7] HOSP SION,INST PATHOL,SION,SWITZERLAND