Pretibial Myxedema: Photos in Ambulatory Care Teaching

 In ambulatory care clinic, we saw a patient with Grave’s disease. The patient also had pretibial myxedema, a dermatological finding typically associated with Grave's disease and constitutes a prong in the classical Triad of the Grave’s disease that includes hyperthyroidism, ophthalmopathy, and dermopathy (even though realistically this dermopathy is only seen in 5% of patients) (1). Pretibial myxedema is characterized by scaly thickening of the skin that is typically slightly pigmented and may assume an orange-peel appearance.

We have learned about pretibial myxedema on several occasions in class. We are often shown the classic image of it – a photo with slight hyperpigmentation over the shins – so this is always how I have also envisioned it. The patient we saw in clinic had this classic presentation of pretibial myxedema so it was not difficult to identify.

After seeing this patient and discussing the case, our preceptor continued to show us a few photos. He didn’t tell us what they were of. One was an image of hyperpigmentation and slight induration in the area of the medial tuberosity. Another showed erythema and slight ulceration over the shins. We didn’t realize it at first, but both were images of pretibial myxedema.

To help develop expertise, it is important that students are exposed to a variety of case and also the spectrum of presentations of the same disorder or clinical feature (2). This is of the greatest challenges of ambulatory care teaching, and perhaps medical education in general, as students often only get the opportunity to see one representation of a disorder during their brief time in any particular site or specialty. Our preceptor’s use of photos (with patient permission), to help capture and convey to his students some of that variety in clinical presentations and clinical cases, which we may otherwise not have the opportunity to see, is a practice that I greatly appreciate. It probably is not easy to develop a treasury of photos of good teaching cases, but certainly it is a technique that would be worth emulating.

(1)  Davies TF. Pretibial myxedema in autoimmune thyroid disease [Internet]. In: Ross DS, editor. UpToDate. 2012[cited 2012 Jan 22] Available from: http://www.uptodate.com.myaccess.library.utoronto.ca/contents/pretibial-myxedema-in-autoimmune-thyroid-disease?source=search_result&search=pretibial+myxedema&selectedTitle=1%7E14

(2) Schmidt HG, Rikers RMJP. How expertise develops in medicine: knowledge encapsulation and illness script formation. [Internet]. Medical education 2007 Dec;41(12):1133-9.[cited 2011 Aug 11] Available from: http://www.ncbi.nlm.nih.gov/pubmed/18004989

-Jenny (Signing off. It was a great selective! Hope you enjoyed reading our musings. :) )