Bilateral Phrenic Nerve Palsy in a Diabetic Causing Respiratory Failure

Increased Frequency of Giant Miniature End-Plate Potentials at the Neuromuscular Junction in Diabetic Rats

There is a need for research addressing the functional characteristics of the motor end-plate in diabetes to identify mechanisms contributing to neuromuscular dysfunction. Here, we investigated the effect of diabetes on spontaneous acetylcholine release in the rat neuromuscular junction. We studied two randomized groups of male Wistar rats (n = 7 per group, 350 ± 50 g, 12-16 weeks of age): one with streptozotocin-induced experimental diabetes, and a healthy control group without diabetes. After 8 weeks of monitoring after diabetes induction, rats in both groups were anesthetized with pentobarbital. Then, the diaphragm muscle was dissected for electrophysiological recordings of miniature end-plate potentials (MEPPs) using a single electrode located at the region of the muscle end-plate. All experiments were conducted at environmental temperature (20-22 °C) in rat Ringer solution with constant bubbling carbogen (95% O2, 5% CO2). Compared to healthy controls, in the diaphragm neuromuscular end-plate derived from diabetic rats, the MEPPs were higher in amplitude and frequency, and the proportion of giant MEPPs was elevated (7.09% vs. 1.4% in controls). Our results showed that diabetes affected the acetylcholine MEPP pattern and increased the number of giant potentials compared to healthy controls.

Rare diabetic neuropathies: It is not only distal symmetrical polyneuropathy

The prevalence of diabetes mellitus is increasing at an epidemic level, leading to a consequent increase of its chronic complications, including neuropathy. Diabetic neuropathy constitutes a heterogeneous group of disorders with distinct clinical presentations and pathophysiological mechanisms. These distinct forms may be categorised according to their clinical presentation as symmetrical (distal symmetrical polyneuropathy, autonomic and acute sensory neuropathy) and focal or multifocal (radiculoplexus neuropathies, entrapment syndromes, cranial palsies and other mononeuropathies). Additionally, people with diabetes may have neuropathies due to causes other than diabetes. The commonest forms of diabetic neuropathy are distal symmetrical polyneuropathy and autonomic neuropathy. However, clinicians should be aware that people with diabetes may suffer from less common forms of neuropathy and should be able to recognise their symptoms and signs. The recognition of the rare diabetic neuropathies is crucial, as they often lead to different clinical outcomes and require different management. The aim of the present narrative, non-systematic review is to outline the rare types of diabetic neuropathies.