Granuloma Annulare - If you have this skin condition, get comprehensive blood sugar testing right away

I first noticed strange raised red circles on my feet and ankles years before I fell into diabetic ketoacidosis in 2018. When they first appeared, I extensively googled what they could be and when I stumbled upon pictures of what is called granuloma annulare, I knew this was what I had. I read this skin condition affects younger, otherwise healthy people, usually women under 30, for unknown reasons. It was at times traced to an autoimmune condition or thyroid disease, but none of my blood work had ever been considered abnormal. Thinking back, there may have been mention of diabetes being the cause on a couple of sites I scrolled through, but I'm certain I immediately dismissed this as ludicrous. I was in my mid 20's and lived at the gym.

I was embarrassed of my skin, and I hoped these circles would just go away like some of the sites said they might, but they stubbornly stuck around for a good year before I decided to finally go to a dermatologist. For a long time, in the optimism of youth, I had a detrimental habit of waiting around for things to just magically become better. That's not something that I do anymore. I was prescribed Clobetasol steroid cream to clear the circles up, and it worked. It was harsh and my skin intensely burned for a week after discontinuing it, but I was glad they were gone. Unfortunately, they kept coming back. I was sitting outside getting some sun on a nice Connecticut summer afternoon, and noticed that they had popped up again seemingly overnight on my feet, ankles and now the side of one of my knees. It wasn't really a lot compared to what I saw on the internet; I would lay awake terrified it would spread over my whole body. Again, I was prescribed Clobetasol, and still not a clue I was diabetic. Puzzled, I thought it might possibly be due to some internal aftermath of Lyme disease, an incredibly prevalent ailment in Connecticut that my whole family has had at some point. 

Long story short, the granuloma annulare has not returned since I have been on insulin with closely monitored blood sugar numbers. Luckily, I have no other health conditions besides the diabetes that could trigger it back -- unfortunately, Type 1 diabetics are more likely to have co-occurring autoimmune disorders.

Today, a web search for "Granuloma Annulare Diabetes" will materialize modern data strongly correlating granuloma annulare to diabetes. The 2019 study Granuloma Annulare: A Rare Dermatological Manifestation of Diabetes Mellitus determined: "Granuloma annulare is usually a self-limited, benign granulomatous disease of the dermis and subcutaneous tissue. It's generalized or disseminated form is associated with underlying diabetes mellitus and at times it precedes the sign and symptoms of diabetes mellitus."

The findings of the 2021 study Association of Granuloma Annulare with Type 2 Diabetes, Hyperlipidemia, Autoimmune Disorders, and Hematologic Malignant Neoplasms suggest that "diabetes and hyperlipidemia may be risk factors for the development of granuloma annulare and that autoimmunity may be an important factor in the pathogenesis of GA."  

The 2020 study Unusual Case of Granuloma Annulare Associated with Diabetes Mellitus stated: "The relationship between GA and diabetes mellitus is still unknown. Since skin lesions preceded the diagnosis of DM in our patient and complete remission of skin changes occurred with induction of insulin therapy, it is important to perform routine laboratory test in every patient."

The 2017 study Granuloma Annulare: Relationship to Diabetes Mellitus, Thyroid Disorders and Tuberculin Skin Test found the fasting blood sugar levels of patients with granuloma annulare were "significantly higher" than the control group. "Granuloma annulare patients are better to be assessed for diabetes mellitus," the researchers advised.

There are dozens of more studies with analogous findings now published online in a wide range of journals. Interestingly, in the mix of all the newer ones, I found one from 1985 on the American Diabetes Association website called Glucose Intolerance in Granuloma Annulare. "Granuloma annulare may be associated with glucose intolerance," the study noted, concluding: "The data taken together suggest that glucose tolerance may be reduced in GA and that insulin resistance may exist."

If you have this skin condition, please don't hesitate to get a thorough blood sugar screening, including fasting blood sugar, HbA1C, the glucose tolerance test and HOMA-IR.