Connective tissue disorders
The connective tissue disorders associated with diabetes draw relatively little attention. However, they occur frequently and cause considerable suffering to patients.
In the pathogenesis of diabetes complications various processes play a part. One of these is the formation of Advanced Glycation Endproducts (AGEs) in blood and tissues by irreversible binding of glucose degradation products to proteins such as albumin, myelin and collagen. This results in pathophysiological processes such as endothelial dysfunction, tissue inflammation, microangiopathy and in changes in the composition and quality of the extracellular matrix. Ultimately, these processes clinically manifest itself as neuropathy, nefropathy, retinopathy or macrovascular disease. However, matrix changes occur in all tissues. It should therefore not come as a surprise that connective tissue disorders affecting skin, tendons, joints, bone and interstitial tissue all occur more frequently in diabetes patients than in the general population. For instance, it has been well documented that loss of elasticity of the interstitial tissue results in restrictive pulmonary changes in diabetes patients. And even a rare connective tissue disorder such as Peyronie's disease seems associated with diabetes. The major clinical manifestations of connective tissue damage are
- Limited Joint Mobility (LJM)
- Dupuytren´s disease
- Flexor tenosynovitis (Trigger finger)
- Carpal Tunnel Syndrome
- Shoulder capsulitis (Frozen shoulder)
- Stiff hand syndrome
- Scleredema diabeticorum (also known as Scleroderma diabeticorum)
- Necrobiosis lipoidica (diabeticorum)
However, the effects of connective tissue damage become most clearly visible in the diabetic foot, where the interaction between vascular damage, neuropathy and limited joint mobility has dramatic consequences. This complex entity is discussed elsewhere in Diapedia.