Levothyroxine anaphylaxis is a rare yet severe adverse reaction to exogenous levothyroxine. While levothyroxine desensitization is commonly employed, its direct application in patients with severe shock poses considerable risks. Omalizumab may offer a potential adjunctive approach to induce tolerance to levothyroxine. We reported a case of a 30-year-old female with a history of thyroid papillary carcinoma who developed anaphylactic shock following oral administration of 50 μg levothyroxine daily after surgery. High serum level of immunoglobulin E (IgE 99.2 kU/L) and positive intradermal tests to all brands of levothyroxine available in China confirm a type Ⅰ hypersensitivity reaction. Several reports have proven the role of omalizumab in desensitization protocol in IgE-mediated diseases; therefore, she was pretreated with three courses of omalizumab (150 mg intradermal injection every four weeks). She then successfully completed oral levothyroxine desensitization and tolerated treatment dose of levothyroxine without experiencing allergic symptoms along with normalization of thyroid function. Further research is warranted to assess its potential as a standard treatment in difficult-to-treat levothyroxine hypersensitivity.

A 22-year-old female has complained of hirsutism, acanthosis nigricans, enlarged clitoris, and menstrual disorders since puberty. Laboratory examinations revealed hyperandrogenemia. Severe insulin resistance and diabetes were found during hospitalization in our hospital. She was diagnosed with type A insulin resistance syndrome finally. After treatment with metformin, the acanthosis nigricans was significantly relieved, blood glucose was controlled satisfactorily, and the menstrual cycle was restored.