Diabetic truncal mononeuropathy--a new clinical syndrome.

Although diabetic mononeuropathy affecting the cranial and peripheral nerves is well recognized, there is little known or documented about diabetic mononeuropathy affecting the thoracic nerves, i.e., the truncal nerves. This series of 40 cases attests to its frequency; equal sex distribution; significance in differential diagnosis including coronary artery disease, intra-abdominal surgical diseases such as gallbladder pathology and appendicitis, pleurisy, and neoplasms. Truncal mononeuropathy has characteristics that differ from those of other diabetic mononeuropathies in that it is primarily sensory and typically not a first manifestation of clinical diabetes, whereas the other forms of diabetic mononeuropathy are primarily motor in effect and not infrequently may be the initial clinical presenting manifestation of diabetes. Finally, diabetic truncal mononeuropathy has a good prognosis.