Acquired thyroid-stimulating hormone, luteinizing hormone, and follicle-stimulating hormone deficiencies with circulating anti-glycoprotein hormones alpha chain-positive cell antibodies.

Background: A patient with systemic lupus erythematosus (SLE) suffered from acquired thyroid-stimulating hormone (TSH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) deficiencies. MRI findings revealed a slight atrophy of the pituitary gland. Further, the serum concentration of the covalent alpha subunit (glycoprotein hormones alpha chain [CGA]) in TSH-, LH-, and FSH-positive cells was below the detectable range. Because SLE is an autoimmune disorder, autoimmunity against the pituitary gland was suspected as the cause of pituitary deficiency.

Methods and results: Immunofluorescence analysis showed that the patient's immunoglobulin G recognized CGA-positive cells in the pituitary gland; therefore, autoimmunity against CGA-positive cells may have caused TSH, LH, and FSH deficiencies in this patient. Moreover, cell-specific autoimmunity impairs pituitary hormone levels. Further research is required to clarify whether acquired TSH, LH, and FSH deficiencies are common in patients with SLE or other autoimmune diseases.

Conclusion: Our findings highlight a unique case of acquired TSH, LH, and FSH deficiencies caused by circulating anti-CGA-positive cell antibodies, introducing a novel clinical concept of acquired hypopituitarism.