[1] Univ Oklahoma, Hlth Sci Ctr, Dept Pediat, Oklahoma City, OK 73190 USA
[2] Case Western Reserve Univ, Sch Med, Div Infect Dis, Dept Med, Cleveland, OH 44106 USA
[3] Overton Brooks VA Med Ctr, Dept Med, Shreveport, LA USA
[4] Case Western Reserve Univ, Sch Med, Dept Pediat, UH Rainbow Babies & Childrens Hosp, Cleveland, OH 44106 USA