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50 Years Ago in THE JOURNAL OF PEDIATRICS

The Route of Insulin Administration in the Management of Diabetes MellitusNora JJ, Smith DW, Cameron JR. J Pediatr 1964;64:547-51

Nora et al administered 131I-labeled lente insulin to 10 children with diabetes and determined a faster clearancetime for insulin administered in the upper arm compared with the thigh and no difference in the rate of insulin

clearance between intramuscular and subcutaneous injections. This study was conducted a little over 30 years from thediscovery of insulin and about a decade after protamine-free, lente insulin became available. In the early 1960s, the firstsynthetic insulin was produced, but it became commercially available only in 1982. In the decade that followed, theadvent of insulin analogs, with various absorption profiles, provided more freedom in dosing and helped with a betterdiabetes control.

What has changed in the past 50 years about diabetes management? We now have a detailed understanding of thepathologic processes that lead to type 1 or type 2 diabetes. We know that tight control of blood glucose levels decreasesthe long-term complications of diabetes, and we have a multitude of insulin formulations to ensure maximumfreedom in management. Technological advances in insulin pens and insulin pumps allow ease of use and better qual-ity of life for children and adults living with diabetes. However, the route of delivery has remained the same, and thefindings by Nora et al have stood the test of time and are accepted as undebatable truths. Subcutaneously administeredinsulin is the mainstay of therapy in diabetes for a simple reason—it is a very effective treatment with minimal adverseeffects. Current efforts aimed at curing diabetes, through transdifferentiation of stem cell into insulin-producing betacell or islet and pancreas transplants, are still far from being viable treatment options and have to raise to the effec-tiveness of insulin therapy.

Diana E. Stanescu, MDDivision of Endocrinology and DiabetesThe Children’s Hospital of Philadelphia

Philadelphia, Pennsylvaniahttp://dx.doi.org/10.1016/j.jpeds.2013.10.078

True Estimate of Glomerular Filtration Rate? 1031