A Case of Atypical Myxedema in Hypothyroidism

In 2019, a case study was conducted on a 33-year-old African American female who presented with a non-resolving papulonodular rash in various parts of her body. The biopsy and laboratory studies revealed that she had myxedema, a skin condition associated with thyroid disease, and severe hypothyroidism. Her thyroid stimulating hormone (TSH) was >100 mcIU/L (reference range, 0.34 - 5.60), free thyroxine (FT4) of 0.34 ng/dL (reference range, 0.58 - 1.64), free triodothyronine (FT3) of 1.2 pg/mL (reference range, 2.0 - 4.4), and thyroid peroxidase antibody level of 274 IU/mL (reference range, 0 - 34). She was started on levothyroxine 250 mcg daily. After two months, her TSH was 0.99 mcIU/L and FT4 was 1.38 ng/dL, and her symptoms of constipation and fatigue had improved, as well as the rash. This case was unusual as myxedema is typically associated with Graves' disease and is usually located pretibially, but in this case, it was present in a patient with severe hypothyroidism and in atypical locations.