[1] King Saud Univ, King Khalid Univ Hosp, Dept Med, Div Pulm & Crit Care Med, Riyadh, Saudi Arabia
[2] King Saud Univ, King Khalid Univ Hosp, Dept Med, Med Intens Care Unit, Riyadh 11472, Saudi Arabia
[3] King Saud Univ, King Khalid Univ Hosp, Dept Family & Community Med, Riyadh 11472, Saudi Arabia
[4] King Saud Univ, King Khalid Univ Hosp, Dept Pathol, Riyadh 11472, Saudi Arabia