THE DIABETIC NEUROPATHIES: TYPES, DIAGNOSIS AND MANAGEMENT

Although over the years the considerable breakthroughs made in our understanding of diabetic neuropathy has come from both neurologists and diabetologists, in recent times (in the UK) it is diabetologists that have assumed the main clinical role in diagnosing and managing the most common neuropathy in the western world. It may therefore be that referral of patients with diabetic neuropathy from the diabetic clinic only occurs if there is a neurologist with a particular interest or if help is required regarding a specific issue such as an atypical clinical picture or pain control. This creates a risk that those training in neurology end up with a somewhat skewed view of the spectrum of diabetic neuropathies. The other situation where neurologists come across diabetic neuropathy is when the patient is found to have diabetes in the course of investigating a peripheral neuropathy. Diagnosis of diabetes mellitus (DM) is made on a combination of typical symptoms—weight loss, thirst, weakness and fatigue—with a persistently raised blood glucose (table 1). Glycosuria and raised HbA1 values alone are not used to make the diagnosis of diabetes mellitus. View this table: Table 1 Biochemical diagnosis of diabetes mellitus Based on a modification of the classification proposed by PK Thomas, a number of distinct syndromes are identifiable (table 2). View this table: Table 2 Classification of the diabetic neuropathies ### Hyperglycaemic neuropathy Tingling paraesthesia, pain or hyperaesthesia in the feet have long been described in patients with newly diagnosed DM or those with very poor glycaemic control, this being the phenomenon of hyperglycaemic neuropathy. The symptoms, and slowing of nerve conduction, are rapidly reversed by improving glucose control. ### Diabetic symmetric distal polyneuropathy with autonomic neuropathy This is the most common diabetic neuropathy and it is characterised by a length related distal distribution of sensory and motor symptoms and signs. As autonomic involvement occurs in many patients with diabetic symmetric distal polyneuropathy (DSDP), and forms an important part …