Deterioration of pituitary function without relapse after steroid therapy for IgG4-related hypophysitis

Glucocorticoid impact therapy for recurrent IgG4-related disease with diabetes insipidus as the main manifestation: A case report and literature review

RATIONALE

There is a relative wealth of experience in the initial treatment of IgG4-related disease (IgG4-RD), but little is known about therapeutic measures for recurrent cases combined with multiple organ and tissue involvement.

PATIENT CONCERNS

A 43-year-old man with a previous diagnosis of IgG4-RD due to recurrent right lacrimal gland enlargement with eyelid erythema presented with diabetes insipidus.

DIAGNOSES

We performed a pituitary Magnetic Resonance Imaging which revealed posterior pituitary rim changes with inhomogeneous enhancement and nodular-like thickening of the pituitary stalk, and performed a water-deprivation-vasopressin test confirmed central diabetes insipidus, and in combination with the patient's elevated IgG4 levels and past medical conditions, we diagnosed central diabetes insipidus, IgG4-related hypophysitis, and IgG4-RD.

INTERVENTIONS

After the patient was admitted to the hospital we gave methylprednisolone 500 mg intravenously once daily for 4 days and again for 4 consecutive days after a 10-day interval. During this period combined with mycophenolate mofetil 250 mg twice daily and desmopressin acetate 0.1 mg 3 times daily.

OUTCOMES

The patient was followed up for a sustained period of 6 months and no side effects of glucocorticoid therapy were noted, there were no signs of recurrence, and the daily urine output stabilized in the normal range.

LESSONS

We recognized that IgG4 levels do not reflect relapse or long-term control, and that glucocorticoid shock therapy is an optional and reliable treatment strategy for relapsed patients.

A case of IgG4-related hypophysitis maintained remission of diabetes insipidus for over 3 months after completion of steroid treatment

Summary

IgG4-related disease is a multiorgan disorder in which nodules and hypertrophic lesions are observed simultaneously, or separately, in areas including the pancreas, liver, lungs, salivary glands, thyroid glands, and pituitary glands. IgG4-related hypophysis is one of several IgG4-related diseases and is characterized by pituitary gland and pituitary stalk thickening, various degrees of hypopituitarism, and increased serum IgG4 levels. Steroid therapy is effective for patients with IgG4-related hypophysis, but the reported effectiveness of steroid therapy for restoring pituitary function differs between studies. Following an episode of autoimmune pancreatitis 10 years prior, enlargement of the pituitary gland and stalk along with panhypopituitarism and polyuria developed in a 73-year-old male. A high serum IgG4 level and biopsy of the submandibular gland showing infiltration of IgG4-positive plasma cells led to a clinical diagnosis of IgG4-related hypophysitis. Prednisolone treatment reduced the swelling of the pituitary gland and stalk and improved anterior pituitary function. Although arginine vasopressin secretion remained insufficient, polyuria was relieved and kept in remission even after prednisolone treatment was completed. This is the first reported case in which prednisolone was able to maintain both normal anterior pituitary function and remission of polyuria caused by IgG4-related hypophysitis. IgG4-related hypophysitis has previously been associated with a relapse of symptoms during treatment. However, the patient reported in this case study remained in remission for over 3 months after completion of steroid treatment and should be monitored closely for changes in pituitary function.

Learning points

Steroid therapy is the first-line therapy for pituitary dysfunction and pituitary stalk swelling in IgG4-related hypophysitis. In this case, although posterior pituitary function remained insufficient, polyuria was relieved and kept in remission for over 3 months even after prednisolone treatment was completed. IgG4-related hypophysitis has been associated with the relapse of symptoms during steroid tapering, and changes in pituitary function and symptoms should be monitored closely. When we encounter cases of adrenal insufficiency and polyuria during observation of autoimmune pancreatitis or other IgG4-related disease, we should consider the possibility of IgG4-related hypophysitis in mind.