Endocrine Abstracts

Introduction: Xanthogranulomatous hypophysitis (XGH) is a very rare form of pituitary hypophysitis that may present both clinically and radiologically as a tumour. Our case series compares paediatric and adult presentations of XGH.

Case series: Patient 1: A 15-year-old female presented with refractory headache, lethargy, short stature, delayed growth (weight (−3.36) SDS, height (−1.73) SDS, BMI 14 kg/m²), and pubertal arrest over 18 months. Formal visual fields demonstrated bitemporal quadrantanopia.

Patient 2: A 21-year-old female presented with lethargy, frontal headaches and secondary amenorrhoea, 3 years after delivery. Postpartum she had normal lactation and menstrual irregularity followed by secondary amenorrhoea. Visual examination was normal.

Patient 3: A 67-year-old man was diagnosed with hypopituitarism following an episode of collapse and intermittent temporal headaches. He had a long standing history of rheumatoid arthritis and rheumatoid nodules within the prostate. Eye examination was normal.

Endocrine investigations demonstrated panhypopituitarism in all three patients. Patient 2 had hyperprolactinaemia requiring Cabergoline.

Pituitary MRI revealed a suprasellar mass compressing the optic chiasm suggestive of craniopharyngioma or rathke’s cleft cyst in patient 1; suspected non-functioning pituitary macroadenoma in patients 2 and 3. MRI demonstrated mixed signal intensities on T1- and T2-weighted sequences.

Following endoscopic trans-sphenoidal surgery, histology revealed areas with cholesterol cleft formation associated with multinucleate giant cells and numerous macrophages in patients 1, 2 and necrobiotic granulomatous chronic inflammatory infiltrate with neutrophils in patient 3. Immunohistochemical staining for IgG4 performed in patient 3 showed IgG4 positive plasma cells (>5%) raising possibility of a systemic IgG4 related process more commonly associated with ocular necrobiotic xanthogranuloma.

Conclusion: This case series describes the spectrum of XGH disease which is yet to be defined. Mixed signal intensities on T1- and T2-weighted MRI sequences may indicate XGH and diagnosis is confirmed by histology. Histological variation may indicate an underlying systemic process.