[Rare differential diagnosis of hyperthyroidism].
METHODS
A 54-year-old female patient is admitted for evaluation of her thyroid function after two cycles of ipilimumab therapy. The decision for the anti-cytotoxic-T-lymphocyte-antigen-4-therapy (anti-CTLA-4) was made two months earlier because of malignant melanoma with pulmonary metastases. The patient was euthyroid before initiation of treatment and without known thyroid disease.


METHODS
The laboratory reveals thyrotoxicosis with elevated anti-thyroid peroxidase and anti-thyroglobulin antibody levels. The anti-thyroid stimulating hormone receptor antibody levels are within the normal range. Thyroid ultrasound shows a normal-sized, inhomogenous, hypoechogenic thyroid gland, consistent with autoimmune thyroiditis.


METHODS
Diagnosis of hyperthyroidism due to ipilimumab-induced autoimmune thyroiditis is made. The patient does not receive any thyroid-specific medication, with regular control of the thyroid hormone levels. When the patient becomes euthyroid, the ipilimumab therapy is continued. Three weeks later, the patient develops hypothyroidism and a supplementation with L-thyroxine is initiated.


CONCLUSIONS
An anti-CTLA-4 therapy may cause thyroid dysfunction. Therefore, before initiation and in the course of the treatment, regular controls of the thyroid hormone levels are required.
Britta
B
Besemer
Karsten
K
Müssig
D000911:Antibodies, Monoclonal / Q000009:adverse effects* / Q000627:therapeutic use*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000139:chemically induced* / Q000175:diagnosis*; D000074324:Ipilimumab; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000556:secondary*; D008545:Melanoma / Q000188:drug therapy* / Q000556:secondary*; D026901:Membrane Transport Proteins / Q000187:drug effects*; D008875:Middle Aged; D012878:Skin Neoplasms / Q000188:drug therapy*; D013960:Thyroid Function Tests; D013967:Thyroiditis, Autoimmune / Q000139:chemically induced* / Q000175:diagnosis*
D000911:Antibodies, Monoclonal; D000074324:Ipilimumab; D026901:Membrane Transport Proteins; C583905:SLC44A4 protein, human