Central diabetes insipidus (CDI), now renamed arginine vasopressin deficiency (AVP-D), is a rare condition characterized by reduced production or secretion of AVP. AVP-D can occur in isolation or in conjunction with anterior pituitary hormone deficiencies.
We present a rare case of Langerhans cells histiocytosis (LCH) diagnosed in adulthood associated with isolated AVP-D. He initially presented with skin manifestations attributed to hidradenitis suppurativa. Due to persistent pain associated with his skin lesions, he underwent a skin biopsy approximately 12 months after initial symptom onset. Histopathology was consistent with LCH. He was commenced on cytarabine. One year later, he developed polyuria and polydipsia. He underwent a water deprivation test which was consistent with AVP-D. He was commenced on desmopressin which adequately addresses his symptoms. Anterior pituitary hormone levels have been routinely monitored and remain unremarkable during 2 years of follow-up. He was transitioned from cytarabine to hydroxyurea and prednisolone for treatment of LCH.
We performed a literature review to assess the risk of developing other anterior hormone deficiencies in patients with isolated AVP-D. Currently, there is limited clinical guidance on how frequently to monitor for the occurrence of these deficiencies. Individuals with a known systemic cause for AVP-D, including LCH, appear to have higher rates of multiple deficiencies compared to those with idiopathic disease. There is a paucity of data regarding potential risk factors that may predict their development particularly in the adult population. Given this, the development of other hormonal deficiencies or panhypopituitarism should be closely monitored for in individuals such as the patient we have presented.