Corneal Confocal Microscopy Detects Early Nerve Regeneration After Pancreas Transplantation in Patients With Type 1 Diabetes

• Published in: Diabetes care Vol. 30; no. 10; pp. 2608 - 2612
• Main Authors: Mehra, Sanjay, Tavakoli, Mitra, Kallinikos, Panagiotis A, Efron, Nathan, Boulton, Andrew J.M, Augustine, Titus, Malik, Rayaz A
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 01.10.2007
• Subjects: analysis; Biological and medical sciences; clinical examination; Clinical trials; Confocal microscopy; cornea; Cornea - cytology; Cornea - innervation; Cornea - pathology; cytology; Diabetes; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 1 - surgery; Diabetes. Impaired glucose tolerance; Diabetic neuropathy; Diabetic Retinopathy; Diabetic Retinopathy - physiopathology; Diabetics; Economic impact; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Evaluation; Fibers; Glycated Hemoglobin; Glycated Hemoglobin A - analysis; Humans; innervation; insulin-dependent diabetes mellitus; kidney transplant; Medical examination; Medical sciences; Metabolic diseases; Microscopy; Microscopy, Confocal; Miscellaneous; Nerve Fibers; Nerve Fibers - pathology; Nerve Regeneration; nerve tissue; Nervous system; Pancreas; Pancreas Transplantation; Pancreas Transplantation - physiology; pathology; Patients; physiology; physiopathology; Public health. Hygiene; Public health. Hygiene-occupational medicine; Reference Values; Regeneration; Research methodology; Studies; surgery; Transplantation; Transplants & implants; United Kingdom; Endocrinopathy; Human; Immunopathology; Nutrition; Patient; Autoimmune disease; Confocal microscopy; Metabolic diseases; Transplantation; Corneal nerve; Regeneration; Treatment; Type 1 diabetes; Surgery; Graft; Early; Pancreas; Endocrinology
• ISSN: 0149-5992; 1935-5548; 1935-5548
• DOI: 10.2337/dc07-0870

OBJECTIVE:--Corneal confocal microscopy (CCM) is a rapid, noninvasive, clinical examination technique that quantifies small nerve fiber pathology. We have used it to assess the neurological benefits of pancreas transplantation in type 1 diabetic patients. RESEARCH DESIGN AND METHODS--In 20 patients with type 1 diabetes undergoing simultaneous pancreas and kidney transplantation (SPK) and 15 control subjects, corneal sensitivity was evaluated using noncontact corneal esthesiometry, and small nerve fiber morphology was assessed using CCM. RESULTS:--Corneal sensitivity (1.54 ± 0.28 vs. 0.77 ± 0.02, P < 0.0001), nerve fiber density (NFD) (13.8 ± 2.1 vs. 42 ± 3.2, P < 0.0001), nerve branch density (NBD) (4.04 ± 1.5 vs. 26.7 ± 2.5, P < 0.0001), and nerve fiber length (NFL) (2.23 ± 0.2 vs. 9.69 ± 0.7, P < 0.0001) were significantly reduced, and nerve fiber tortuosity (NFT) (15.7 ± 1.02 vs. 19.56 ± 1.34, P = 0.04) was increased in diabetic patients before pancreas transplantation. Six months after SPK, 15 patients underwent a second assessment and showed a significant improvement in NFD (18.04 ± 10.48 vs. 9.25 ± 1.87, P = 0.001) and NFL (3.60 ± 0.33 vs. 1.84 ± 0.33, P = 0.002) with no change in NBD (1.38 ± 0.74 vs. 1.38 ± 1.00, P = 1.0), NFT (15.58 ± 1.20 vs. 16.30 ± 1.19, P = 0.67), or corneal sensitivity (1.23 ± 0.39 vs. 1.54 ± 00.42, P = 0.59). CONCLUSIONS:--Despite marked nerve fiber damage in type 1 diabetic patients undergoing pancreas transplantation, small fiber repair can be detected within 6 months of pancreas transplantation using CCM. CCM is a novel noninvasive clinical technique to assess the benefits of therapeutic intervention in human diabetic neuropathy.