Autoimmune polyglandular endocrinopathy and anterior hypophysitis in a 14 year-old girl presenting with delayed puberty

A rare case of pituitary infarction leading to spontaneous tumour resolution and CSF-sella syndrome in an 11-year-old girl and a review of the paediatric literature

Pituitary infarction or apoplexy with spontaneous cure of the underlying pituitary adenoma is rare. In the paediatric population, we found only a few reported cases. We report a rare case of pituitary infarction progressing to CSF-sella syndrome (or empty sella) in an 11-year-old girl. She presented with sudden onset vomiting, moderate headaches, lethargy, weight loss, and tall stature above her mid-parental height. She did not have any severe symptoms of apoplexy. Her clinical and radiological findings suggested infarction of a pituitary lesion, such as a pituitary adenoma or infarction of a cystic lesion, such as a Rathke's cleft cyst. In this report, we discuss her case of probable infarction of a growth hormone secreting adenoma with a phase of accelerated growth ending up with total anterior pituitary insufficiency. The differential diagnosis and review of the rare cases of paediatric pituitary infarction in the literature will be discussed.

Autoantibodies against pituitary proteins in patients with adrenocorticotropin-deficiency

BACKGROUND

An autoimmune cause of adrenocorticotropin (ACTH)-deficiency is presented, as it is known to be a characteristic feature of lymphocytic hypophysitis, a disease of the pituitary gland considered to be autoimmune.

MATERIALS AND METHODS

The aim of this study was twofold: (1) to evaluate the occurrence of pituitary autoantibodies and (2) to correlate it to clinical and immunological features in a large group of patients with ACTH-deficiency of possible autoimmune aetiology. Sixty-five patients with ACTH-deficiency and 57 healthy subjects participated in the study. Pituitary autoantibodies were measured by an immunoblotting assay with human pituitary cytosol as antigen.

RESULTS

Autoantibodies to a novel 36-kDa pituitary autoantigen were seen in sera from 18.5% (12/65) patients and only 3.5% (2/57) of control subjects (P = 0.0214). When taking only those subjects with strong immunoreactivity into account, the significance was lost; P = 0.3642. Immunoreactivity to a 49-kDa pituitary autoantigen was observed in 21.5% (14/65) of ACTH-deficient patients compared with 8.8% (5/57) of control subjects (P = 0.0910). This 49-kDa pituitary autoantigen has recently been identified as neurone-specific enolase and a candidate marker for neuroendocrine autoimmunity. Clinical parameters in patients with positive versus those with negative pituitary immunoreactivity did not differ. However, autoantibodies to thyroglobulin were positively correlated to immunoreactivity against the 36-kDa pituitary autoantigen (P = 0.014).

CONCLUSIONS

Our findings of pituitary autoantibodies in patients' sera support the theory that an autoimmune destruction of corticotrophs may be the underlying cause of hormonal deficit in some patients with ACTH-deficiency.

Factors affecting the susceptibility of the mouse pituitary gland to CD8 T-cell-mediated autoimmunity

We have previously shown, in a transgenic mouse model, that the pituitary gland is susceptible to CD8 T-cell-mediated autoimmunity, triggered by a cell-specific model autoantigen, resulting in pan-anterior pituitary hypophysitis and dwarfism. In the present study, we now demonstrate that antigen dose, the T-cell precursor frequency, the degree of lymphopenia and the context of target antigen expression, are important parameters determining the time course and extent of the pathological consequences of CD8 T-cell-mediated autoimmunity. Furthermore, our data indicate that the pituitary gland is susceptible to CD8 autoimmunity following an inflammatory insult such as a viral infection. As lymphocytic hypophysitis may be manifest in other autoimmune conditions, and the pituitary gland may be susceptible to T-cell-mediated pathology after immunization with a virus expressing soluble pituitary antigen, it is important to consider that strategies based on vaccination against soluble pituitary gonadotrophins could have other unexpected endocrine consequences.