Rapid Glycaemic Control Leading to Painful Neuropathy: A Case of Treatment-Induced Neuropathy of Diabetes in a Young Patient.

INTRODUCTION: Intensive glycaemic control is essential for managing Type 1 Diabetes Mellitus (T1DM), yet rapid metabolic optimization can trigger Treatment-Induced Neuropathy of Diabetes (TIND). This iatrogenic condition, characterized by acute neuropathic pain and autonomic dysfunction, is increasingly relevant with the use of advanced automated insulin delivery (AID) systems. CASE PRESENTATION: A 19-year-old male with a 10-year history of poorly controlled T1DM (baseline HbA1c 13.7%) was transitioned to an automated hybrid closed-loop system (Medtronic MiniMed 780G). Following a rapid HbA1c reduction of 6.3% over six weeks, the patient developed severe, "electric shock-like" neuropathic pain in the lower limbs and upper back without associated autonomic nervous system involvement. Nerve conduction studies confirmed a length-dependent sensorimotor axonal polyneuropathy. The patient's pain was refractory to duloxetine but showed significant improvement with gabapentin alongside clinical recovery observed over 4 weeks. To stabilize glucose levels, the AID system was discontinued in favor of a less intensive multiple daily injection (MDI) regimen. CONCLUSION: Rapid glycemic correction in patients with high baseline HbA1c carries a significant risk of TIND. Clinicians should consider close monitoring and individualized adjustment of blood glucose descent in high-risk individuals, even when utilizing advanced AID systems, to prevent debilitating neurological complications.