Successful immunomodulatory treatment for recurrent xanthogranulomatous hypophysitis in an adolescent: illustrative case

Secondary xanthogranulomatous hypophysitis mimicking a pituitary macroadenoma: a case report

Hypophysitis is an extremely rare inflammatory disease that can mimic the clinical and radiological features of a pituitary adenoma. In this case report, we describe a 45-year-old woman with secondary xanthogranulomatous hypophysitis (XGH) who presented with signs of a pituitary macroadenoma. The patient complained of headaches, visual impairment, and amenorrhea-galactorrhea syndrome. Her physical examination was normal. Laboratory investigation revealed corticotropin, thyrotropin, and gonadotropin deficiencies. She also had low visual acuity in her right eye and an altered visual field. Pituitary magnetic resonance imaging revealed an intra and suprasellar mass measuring 13 × 11 × 16 mm, with hemorrhagic necrosis, that was having a discrete mass effect on the patient's optic chiasm and pituitary stalk. The patient was treated with hydrocortisone and levothyroxine, and then transferred to the Neurosurgery department for total transsphenoidal resection of the mass. Histological examination of the tumor permitted a diagnosis of XGH of a remodeled Rathke's pouch cyst to be made. Systemic conditions such as tuberculosis, sarcoidosis, and other granulomatous diseases were excluded. The etiopathogenesis of XGH remains poorly characterized, but it may be a progressive form of lymphocytic hypophysitis or a remodeled Rathke's pouch cyst. Screening for autoimmune pathology and systemic diseases is essential to guide appropriate management.

A novel approach to hypophysitis: outcomes using non-glucocorticoid immunosuppressive therapy

OBJECTIVE

To determine pituitary function before and after nonglucocorticoid immunosuppressive therapy (NGIT) in subjects with hypophysitis and evaluate their clinical and radiologic outcomes.

DESIGN

Retrospective, longitudinal study.

METHODS

We reviewed a large database, selected subjects with hypophysitis treated with NGIT, and collected information on the duration of therapy, and clinical, hormonal, and radiologic outcomes.

RESULTS

Twelve subjects met the inclusion criteria. Five subjects had primary hypophysitis (PH), while seven had secondary hypophysitis (SH) due to an underlying systemic inflammatory disease. Mean age ± SD was 48.0 ± 15.7 years and 40.9 ± 13.0 years, for PH and SH, respectively. The majority were female (PH 60% and SH 86%). BMI ± SD at presentation was 25.2 ± 2.5 kg/m2 and 26.8 ± 6.7 kg/m2 for PH and SH, respectively. The most common symptom at presentation was fatigue (75%). All PH subjects (100%) and 2 (28.6%) SH subjects had polyuria/polydipsia. There was a significant decrease in mean pituitary stalk thickness after NGIT (P = .0051) (mean duration 16.5 ± 4.8 months). New hormone loss or recovery occurred rarely. Mycophenolate mofetil was the most used NGIT: adverse effects prompted discontinuation in 2 out of 7 subjects.

CONCLUSIONS

Subjects with hypophysitis receiving NGIT had stable or improved brain/pituitary magnetic resonance imaging findings with a significant decrease in pituitary stalk thickness. NGITs did not improve anterior pituitary function. Our findings suggest that NGIT may be considered as an alternative therapy for patients with hypophysitis who require immunosuppression.

Unveiling the Etiopathogenic Spectrum of Hypophysitis: A Narrative Review

Hypophysitis, a rare inflammatory disorder of the pituitary gland, has seen an uptick in reported cases in recent years. Our objective is to summarize the most recent research on the etiopathogenesis, molecular mechanisms, and genetics of both primary and secondary hypophysitis. Primary autoimmune hypophysitis (PAH): During the acute phase of the disease, the pituitary gland in enlarged due to the infiltration of T and B lymphocytes. The chronic phase is characterized by progressive and irreversible pituitary atrophy. APA may play a role in the management, diagnosis, and prognosis of PAH. Specific autoantibodies such as anti-GH, anti-PIT-1, and anti-T-PIT have been found in patients with hypophysitis and hypopituitarism. A recent study suggested that a mechanism of escaping clonal deletion and mounting an immune response against self antigens can explain the unusual nature of the immune response observed in PAH patients. A cytokine array shows the presence of gamma-interferon and interleukin-17. Patients carrying mutations in the PIT1 or PROP1 genes may present PAH. Individuals carrying the HLA DQ8 haplotype are four times more likely to develop PAH. Immune checkpoint inhibitors induce hypophysitis (IIHs): IIHs is an increasingly frequent toxicity of in patients on treatment with inhibitors targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death-1 (PD-1). ICIs inhibit the CTLA-4 pathway, leading to overactivation of T lymphocytes. The binding of PD-1/PD-L1 suppresses the activity of T cells, promotes the conversion of T-helpers into T-regulatory cells, and activates pro-survival signaling pathways in cancer cells. Cytokines play a crucial role in IIHs. B-cell infiltration has been observed in IIHs, suggesting that antibody-mediated pituitary injury may contribute. Genetic polymorphisms of CTLA-4 and PD-1 genes can increase the risk of IIHs. HLA alleles may also be involved in the onset of IIHs; this HLA association presents a possible alternative mechanistic hypothesis. IIHs may also be linked to a paraneoplastic syndrome triggered by ectopic expression of pituitary specific antigens. SARS-CoV-2-related hypophysitis: Recently, the literature has reported occurrences of hypophysitis associated with the SARS-CoV-2 virus; long COVID-19 may also present as infundibulo-neuro-hypophysitis. The virus enters the central nervous system because of its distinct interaction with angiotensin-converting enzyme receptors via spike proteins binding the capillary endothelium, and it directly damages the pituitary cells. The effect of SARS-CoV-2 can occur indirectly through inflammation and the release of cytokines. The exact mechanism remains ambiguous. The available data on endocrine complications associated with the SARS-CoV-2 vaccine are scant. Nonetheless, isolated cases of hypophysitis have been documented. Treatment of hypophysitis: Glucocorticoids are the cornerstone in managing primary hypophysitis, given their targeted action on inflammation. A better understanding of the etiopathogenesis and molecular mechanism of hypophysitis can lead to more effective and personalized treatment strategies.

Hypophysitis: Defining Histopathologic Variants and a Review of Emerging Clinical Causative Entities

Inflammatory disease of the pituitary gland is known as hypophysitis. There are multiple histological subtypes, the most common being lymphocytic, and the pathogenesis is variable and diverse. Hypophysitis can be primary and idiopathic or autoimmune related, or secondary to local lesions, systemic disease, medications, and more. Although hypophysitis was previously accepted as an exceedingly rare diagnosis, a greater understanding of the disease process and new insights into possible etiologic sources have contributed to an increased frequency of recognition. This review provides an overview of hypophysitis, its causes, and detection strategies and management.