Patients with ANCA-associated vasculitis (AAV) with central diabetes insipidus (CDI) have more manifestations involving the ear, nose, and throat (ENT) and lower incidences of kidney disease, according to a study published in Frontiers in Endocrinology.
CDI and AAV both are rare conditions, although there seems to be an association between the two. Epidemiological studies suggest that around 1.3% to 3.9% of patients with AAV also have CDI. The likely explanation of this association is the involvement of vasculitis affecting the pituitary vasculature; should AAV-associated CDI be diagnosed, physicians should avoid unnecessary biopsies of the pituitary gland, which can lead to its partial loss of function.
Despite the known association between the two conditions, there has been no prolonged follow-up studies involving patients with AAV-associated CDI. The authors of the study sought to assess the disease burden, treatment, and prognosis of these patients by analyzing the genetic and clinical characteristics of affected individuals.
The authors enrolled patients with both disorders seen at the Peking Union Medical College Hospital, with a follow-up period between January 2012 and April 2022. Patients with a possible alternate cause for CDI were excluded. Selected participants were case-control matched with individuals with AAV but without CDI in a 1:5 ratio.
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This retrospective study involved the collection of extensive clinical data, including laboratory findings and magnetic resonance imaging data. The research team assessed kidney damage using the estimated glomerular filtration rate (eGFR). The follow-ups were conducted every 3 to 6 months, during which new symptoms were assessed, particularly those involving the pituitary gland.
The research team included 1203 patients in this study; 16 had AAV-associated CDI. An overwhelming percentage of patients—81.3%—had symptoms related to ENT issues. However, patients with AAV-associated CPI appeared to have lower incidences of renal disease (eGFR was 121.8 compared with to 73.7 mL/min/1.73 m2 in non-CDI patients with AAV).
Due to the rarity of this condition and the challenges of conducting long-term follow-ups, future studies involving larger cohorts are needed to further validate the results of this study.
Chen X, Zhang S, Peng X, et al. Clinical characteristics and primary outcomes of patients with ANCA-associated vasculitis and central diabetes insipidus. Front Endocrinol (Lausanne). Published online May 12, 2023. doi:10.3389/fendo.2023.1173903