Localized granulomatosis with polyangiitis (loc-GPA) is a milder disease state of GPA restricted to the respiratory tract. Transition from localized form to systemic/generalized disease is predicted to occur in approximately 10% of the patients. We report an unusual case of loc-GPA involving multiple cranial nerves, which in 3 years progressed into systemic disease involving pituitary gland. Initially antineutrophil cytoplasmic antibody (ANCA) was negative, but as symptoms of diabetes insipidus started, ANCA became positive. Clinical course of ANCA negative loc-GPA should be carefully monitored for development of systemic disease. ANCA may be a useful marker for detecting transition from localized to systemic disease.
Antibodies, Antineutrophil Cytoplasmic ; Cranial Nerves ; Diabetes Insipidus ; Granulomatosis with Polyangiitis* ; Humans ; Pituitary Gland ; Respiratory System