Poster Presentation The International Congress of Neuroendocrinology 2014

Two cases of non-neoplastic pituitary mass lesions: Primary hypothyroidism and IgG4-related hypophysitis (#332)

Kazuhiro Takahashi 1 2
  1. Department of Endocrinology and Applied Medical Science, Tohoku University Graduate School of Medicine, Sendai, Japan
  2. Department of Medicine, Yamaga Clinic, Takeda General Hospital, Aizu-Wakamatasu, Japan

Pituitary enlargement is caused, not only by tumors, but also by inflammatory diseases and others.
Case 1: A 30-year-old female patient visited a gynecological clinic because of irregular menstruation and general malaise. Humoral examination showed an elevated plasma level of prolactin (152.9 ng/ml). MRI showed an enlarged pituitary gland. She was referred to our endocrine clinic. She had no headache or visual field defect. In addition to the elevated plasma prolactin level, plasma level of TSH (1118 μIU/ml) was elevated with decreased plasma levels of free T3 (<1. 0 ng/dl) and free T4 (<0.4 ng/dl). Anti-thyroglobulin antibody and anti-thyroid peroxidase antibody were positive. Primary hypothyroidism with Hashimoto’s thyroiditis was diagnosed. Pituitary enlargement was improved after the treatment by thyroxine.
Case 2: A 70-year-old male patient visited the gastrointestinal outpatient department of Takeda General Hospital because of anorexia, weight loss and general malaise. Examinations by abdominal CT, gastrofibroscope, and colon fibroscope showed no remarkable findings. He was referred to our endocrine clinic because of decreased plasma level of TSH (0.021 μIU/ml) with normal plasma levels of free T3 and free T4. Plasma levels of cortisol (1.0 μg/dl), IGF-1 (42 ng/ml) and vasopression (0.3 pg/ml) were also decreased. MRI showed a mass lesion in pituitary. Serum level of IgG4 was elevated (312 mg/dl), whereas serum levels of ACE, anti-nuclear antibodies or ANCA were within normal ranges. Possible IgG4-related hypophysitis was diagnosed. Pituitary mass lesion was improved after the treatment by predonisolone (20 mg/day p.o.).
Conclusion: Careful evaluation of imaging studies, and biochemical and humoral data would be important to the diagnosis and the management of patients with enlarged pituitary.
Acknowledgment: The author is very grateful to Dr. H. Sato (Department of Neurosurgery, Takeda General Hospital) for his valuable comments and advice.