Delayed umbilical cord detachment leukocytosis is seen in?

Ans is 'a' i.e. Leukocyte adhesion deficiency * Delayed separation of the umbilical cord is pathognomonic for leukocyte adhesion deficiency (autosomal recessive). It's due to absence of CD 18 antigen that's necessary for formation of integrins, the substances that are responsible for the second step of leukocyte migration: adhesion. Because the leukocytes cannot efficiently reach the site of insult, they cannot engulf the offending substance, and no pus will be evident. Also, as a compensatory mechanism, there may be excessive leukocytosis.