Endocrine Abstracts

Case history: This 28 year old lady with a new diagnosis of T1DM (April 22) and uveitis complained of severe pain over the trunk described as a burning sensation but not associated with any neurological deficit. There is no history of head trauma, neck trauma or radiation to head and neck area and no skin changes or spinal deformity. She has developed this pain after starting insulin in April 22.

Investigations: May 22: Hb 119, MCV: 85.0; U&Es:normal; LFTs:normal; HbA1c;107; TSH 1.9, freeT4 15.4, B12:520, folate 6.7, ferritin 17, Vitamin D 37, TTG 1.1; September 22: HbA1c: 41 Borrelia Burgdoferi antibodies: negative; syphilis serology: negative MRI brain and spinal cord: no areas concerning of demyelination.

Results and treatment: Diagnosis was made as insulin neuritis or Treatment-induced neuropathy in diabetes (TIND). TIND is a condition characterized by severe distal distal limb pain, damage in the peripheral nerve fibre and autonomic dysfunction, preceded by a period of rapid glycaemic control. It has been reported in both type 1 and type 2 diabetics treated with insulin or oral hypoglycaemic agents who typically have a history of poor glycaemic control. Pathogenesis of TIND is unknown, with proposed mechanisms including endoneurial ischaemia, hypoglycaemic microvascular neuronal damage and regenerating nerve firing. Pain can affect other areas including the trunk and abdomen, or be more generalised (1). Initially, she was started on Gabapentin, but no improvement. Therefore, amitriptyline and pregabalin were started and her symptoms have improved.

Conclusions and points for discussion: Patients with TIND are at a high risk of associated microvascular disease. Most patients had rapid progression of retinopathy that developed in conjunction with the onset of neuropathic pain (2). In our case, her HbA1c dropped from 107 to 41 in less than 6 months. There is a significant increase in incidence of TIND when the decrease in HbA1c is > 2% over 3 months. Patients with a higher baseline HbA1c, a history of diabetic anorexia or weight loss may be at high risk for TIND and particular care is warranted with intensive glycaemic management of these patients. (3)

References: 1. Insulin neuritis and diabetic cachectic neuropathy: a review; Michael Knopp, Maithili Srikantha, Yusuf A Rajabally;Curr Diabetes Rev. May 2013.2. Gibbons CH, Freeman R. Treatment-induced diabetic neuropathy: a reversible painful autonomic neuropathy. Ann Neurol 2010;.3. Treatment-induced neuropathy of diabetes: an acute, iatrogenic complication of diabetes;Christopher H. Gibbons and Roy Freeman;BRAIN 2015