Cyclic neutropenia

Cyclic neutropenia (CyN) is a rare hematologic disorder and form of congenital neutropenia that tends to occur approximately every three weeks and lasting for few days at a time due to changing rates of neutrophil production by the bone marrow. It causes a temporary condition with a low absolute neutrophil count and because the neutrophils make up the majority of circulating white blood cells it makes the body in severe risk to inflammation and infection. [Source: Wikipedia ]

OrphaNet reference
Cyclic neutropenia 
May Cause
Early loss of teeth