From the Research
The prevalence of Ashkenazi Jewish females presenting with new-onset pre-tibial plaques after age 40 is not precisely established in medical literature, but this presentation may suggest pretibial myxedema associated with thyroid disorders, particularly Graves' disease. Thyroid disorders occur at higher rates in the Ashkenazi Jewish population, with some studies indicating prevalence rates of autoimmune thyroid disease approximately 1.5-2 times higher than in the general population 1. When an Ashkenazi Jewish woman over 40 presents with pre-tibial plaques, a thorough thyroid evaluation is recommended, including TSH, free T4, and thyroid antibody testing. These lesions typically appear as waxy, flesh-colored to reddish-brown plaques on the anterior shin area. Management focuses on treating the underlying thyroid condition with appropriate medication (methimazole 5-30 mg daily or propylthiourium 50-300 mg daily for hyperthyroidism, or levothyroxine for hypothyroidism) 2. Topical high-potency corticosteroids under occlusion may help with the skin manifestations. The genetic predisposition to autoimmune disorders in the Ashkenazi Jewish population relates to specific HLA haplotypes and other genetic factors that influence immune regulation, which explains the potentially higher occurrence of these thyroid-related skin manifestations in this demographic group. Some key points to consider in the diagnosis and management of thyroid disorders include:
- The use of laboratory tests such as TSH, free T4, and thyroid antibody testing to diagnose and monitor thyroid function 3, 4, 1
- The importance of considering the clinical context when interpreting laboratory results, including the potential for assay interferences and the effects of concurrent medications 1
- The role of hematological parameters, such as mean platelet volume (MPV), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), in the diagnosis and prognosis of subacute thyroiditis patients 5