Severe pertussis and hyperleukocytosis: is it time to change for exchange?

Background: Pertussis is an important cause of infant death worldwide and continues to be a public health concern even in countries with high vaccination coverage. Severe (critical) pertussis with hyperleukocytosis is a severe form of the disease with up to 80% mortality rate. Attempts have been reported to reduce the white blood cell burden by exchange transfusion (ET) with conflicting conclusions.