Developmental lactase insufficiency
In some cases of premature birth, baby’s small intestine is not completely able to secrete lactase and hence they appear to have lactase deficiency at birth. As they mature however, they acquire the ability to secrete lactase. This is termed as a developmental lactase deficiency.
Knowing about the underlying cause of the conditions is essential to establish diagnosis, treatment plan to prevent further complications. More insight of molecular working of lactose intolerance is still required for which more researches are still to be conducted.