Hypothalamic-Pituitary Autoimmunity and Related Impairment of Hormone Secretions in Chronic Fatigue Syndrome.

CONTEXT: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severe chronic illness that reduces the quality of life. A potential role of neuroendocrine autoimmune dysfunction has been hypothesized. OBJECTIVE: This work aims to investigate the occurrence of antipituitary (APA) and antihypothalamic (AHA) antibodies and possible related hypothalamic/pituitary dysfunctions in ME/CSF patients. METHODS: This is a case-control study conducted in a university hospital setting (Stanford, California, USA; and Naples, Italy). Thirty women with ME/CSF (group 1) diagnosed according to Fukuda, Canadian, and Institute of Medicine criteria, at Stanford University, were enrolled and compared with 25 age-matched healthy controls. APA and AHA were detected by immunofluorescence; moreover, we investigated hormonal secretions of anterior pituitary and respective target glands. APA and AHA titers both were assessed and the prevalence of pituitary hormone deficiencies was also investigated. RESULTS: Patients in group 1 showed a high prevalence of AHA (33%) and APA (56%) and significantly lower levels of adrenocorticotropin (ACTH)/cortisol, and growth hormone (GH) peak/insulin-like growth factor-1 (IGF-1) vs controls (all AHA/APA negative). Patients in group 1A (13 patients positive at high titers, ≥ 1:32) showed ACTH/cortisol and GH peak/IGF-1 levels significantly lower and more severe forms of ME/CFS with respect to patients in group 1B (7 positive at middle/low titers, 1:16-1:8) and 1C (10 antibody-negative patients). CONCLUSION: Both AHA and/or APA at high titers were associated with hypothalamic/pituitary dysfunction, suggesting that hypothalamic/pituitary autoimmunity may play an important role in the manifestations of ME/CFS, especially in its more severe forms.

Remission of Pituitary Autoimmunity Induced by Gluten-Free Diet in Patients With Celiac Disease.

CONTEXT: An improvement of some autoimmune diseases associated with celiac disease (CD) has been observed after a gluten-free diet (GFD). OBJECTIVE: The aim of this longitudinal study was to evaluate the effect of a GFD on autoimmune pituitary impairment in patients with CD and potential/subclinical lymphocytic hypophysitis (LYH). DESIGN: Five-year longitudinal observational study. SETTING: Tertiary referral center for immunoendocrinology at the University of Campania "Luigi Vanvitelli". PATIENTS: Ninety-three newly diagnosed LYH patients (high titer of antipituitary antibodies [APA] and normal or subclinically impaired pituitary function) were enrolled from 2000 to 2013 and grouped as follows: group 1, consisting of 43 patients with LYH + CD, and group 2, consisting of 50 patients with isolated LYH only. INTERVENTION: A GFD was started in patients in group 1 after the diagnosis of CD. MAIN OUTCOME MEASURES: APA titers and pituitary function were evaluated at the beginning of the study and then yearly for 5 years in both groups. Patients progressing to a clinically overt LYH were excluded from the follow-up. RESULTS: Complete remission of LYH (disappearance of APA and recovery of pituitary function in patients with previous subclinical hypopituitarism) occurred in 15 patients in group 1 after a GFD (34%) and spontaneously in only 1 patient in group 2 (2%) (P < .001). Two patients in group 1 and 25 in group 2 progressed to a clinically overt hypopituitarism and dropped out from the study to receive an appropriate replacement therapy. The presence of CD was the only independent predictor of pituitary function recovery (hazard ratio [HR] 0.059, 95% confidence interval [CI] 0.01-0.54, P = .012). CONCLUSION: In patients with LYH and CD, a GFD may be able to induce remission of subclinical LYH, or prevent the progression to clinical stage of this disease.

The role of autoimmunity in pituitary dysfunction due to traumatic brain injury.

PURPOSE: Traumatic brain injury (TBI) is one of the most common causes of mortality and long-term disability and it is associated with an increased prevalence of neuroendocrine dysfunctions. Post-traumatic hypopituitarism (PTHP) results in major physical, psychological and social consequences leading to impaired quality of life. PTHP can occur at any time after traumatic event, evolving through various ways and degrees of deficit, requiring appropriate screening for early detection and treatment. Although the PTHP pathophysiology remains to be elucitated, on the basis of proposed hypotheses it seems to be the result of combined pathological processes, with a possible role played by hypothalamic-pituitary autoimmunity (HPA). This review is aimed at focusing on this possible role in the development of PTHP and its potential clinical consequences, on the basis of the data so far appeared in the literature and of some results of personal studies on this issue. METHODS: Scrutinizing the data so far appeared in literature on this topic, we have found only few studies evaluating the autoimmune pattern in affected patients, searching in particular for antipituitary and antihypothalamus autoantibodies (APA and AHA, respectively) by simple indirect immunofluorescence. RESULTS: The presence of APA and/or AHA at high titers was associated with an increased risk of onset/persistence of PTHP. CONCLUSIONS: HPA seems to contribute to TBI-induced pituitary damage and related PTHP. However, further prospective studies in a larger cohort of patients are needed to define etiopathogenic and diagnostic role of APA/AHA in development of post-traumatic hypothalamic/pituitary dysfunctions after a TBI.