Acute diabetic neuropathy following improved glycaemic control: a case series and review

Abstract

Summary We present three cases of acute diabetic neuropathy and highlight a potentially underappreciated link between tightening of glycaemic control and acute neuropathies in patients with diabetes. Case 1: A 56-year-old male with poorly controlled type 2 diabetes (T2DM) was commenced on basal-bolus insulin. He presented 6 weeks later with a diffuse painful sensory neuropathy and postural hypotension. He was diagnosed with treatment-induced neuropathy (TIN, insulin neuritis) and obtained symptomatic relief from pregabalin. Case 2: A 67-year-old male with T2DM and chronic hyperglycaemia presented with left lower limb pain, weakness and weight loss shortly after achieving target glycaemia with oral anti-hyperglycaemics. Neurological examination and neuro-electrophysiological studies suggested diabetic lumbosacral radiculo-plexus neuropathy (DLPRN, diabetic amyotrophy). Pain and weakness resolved over time. Case 3: A 58-year-old male was admitted with blurred vision diplopia and complete ptosis of the right eye, with intact pupillary reflexes, shortly after intensification of glucose-lowering treatment with an SGLT2 inhibitor as adjunct to metformin. He was diagnosed with a pupil-sparing third nerve palsy secondary to diabetic mononeuritis which improved over time. While all three acute neuropathies have been previously well described, all are rare and require a high index of clinical suspicion as they are essentially a diagnosis of exclusion. Interestingly, all three of our cases are linked by the development of acute neuropathy following a significant improvement in glycaemic control. This phenomenon is well described in TIN, but not previously highlighted in other acute neuropathies. Learning points: A link between acute tightening of glycaemic control and acute neuropathies has not been well described in literature. Clinicians caring for patients with diabetes who develop otherwise unexplained neurologic symptoms following a tightening of glycaemic control should consider the possibility of an acute diabetic neuropathy. Early recognition of these neuropathies can obviate the need for detailed and expensive investigations and allow for early institution of appropriate pain-relieving medications.

The Association Between the Decline of eGFR and a Reduction of Hemoglobin A1c in Type 2 Diabetic Patients

“…There may be concerns about whether a decrease in eGFR indicates the decline of renal function, since the link between acute intensive glycemic control and acute neuropathies or DR progression is described in the literature (25)(26)(27)(28). The neuropathies experienced by patients were acute, severe but reversible, and did not occur as a consequence of chronic hyperglycemia.…”

Treatment-induced neuropathy of diabetes related to abrupt glycemic control

“…Several other studies, including one that described the syndrome in women with eating disorders, corroborated an increased risk of treatment-induced neuropathy of diabetes after rapid correction of HbA 1c . 1,[3][4][5][6] The mechanisms leading to treatment-induced neuropathy of diabetes are thought to be related to apoptosis induced by sudden glucose deprivation, the formation of arteriovenous shunts causing endoneural ischemia and regeneration of nerve fibres causing pain. 4,7 It occurs more frequently in patients with type 1 than in those with type 2 diabetes: 1 study reported that 76 out of 104 patients with treatment-induced neuropathy of diabetes had type 1.…”

“…1,9 Therefore, some experts suggest a period of permissive hyperglycemia as a "salvage treatment," whereas others have questioned this approach. 6,10 A small longitudinal cohort study followed 26 patients with treatment-induced neuropathy of diabetes for 8 years. 1 All 19 patients who maintained stable, adequate glycemic control (HbA 1c between 6% and 8.5%) after the development of symptoms of treatment-induced neuropathy of diabetes had gradual improvement in their neuropathic symptoms over several years, with near-complete functional recovery, which suggests that the syndrome is reversible to some degree.…”

Neuropathie induite par le traitement du diabète associée à une correction soudaine du contrôle glycémique

“…Certaines études de cas et de cohorte ont montré que la neuropathie douloureuse pourrait s'améliorer de façon substantielle après avoir allégé le contrôle glycémique; 1 étude a aussi souligné une amélioration de la rétinopathie diabétique précoce 1,9 . De ce fait, certains experts suggèrent une période de tolérance d'hyperglycémie comme « traitement de rattrapage », alors que d'autres ont mis en doute cette approche 6,10 . Une petite étude de cohorte longitudinale a suivi 26 patients présentant une neuropathie induite par le traitement du diabète pendant 8 ans 1 .…”