This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Rabson-Mendenhall syndrome (RMS) is a mild form of INSR-related severe syndromic insulin resistance, an inherited disorder associated with the inability to regulate blood sugar. Insulin is a hormone produced by the pancreas that normally regulates blood sugar levels by promoting the movement of sugar (glucose) into cells for energy production or into the liver and fat cells for storage. Symptoms of RMS include poor growth before and after birth, hairiness, muscle wasting (hypertrophy), coarse facial features, abnormalities of the teeth and nails and a skin abnormality known as acanthosis nigricans. In addition, people with RMS have excess blood insulin levels and irregular sugar (glucose) levels. Some people with RMS have developmental and intellectual disabilities. Over time, people with RMS can have organ damage due to unregulated blood sugar. This disorder is diagnosed based on the signs and symptoms, laboratory testing, and genetic testing of the INSR gene.
RMS is caused by a mutation in the INSR gene and is inherited in an autosomal recessive manner. Treatment is difficult and may include high doses of insulin and/or recombinant insulin-like growth factor. The long-term outlook for people with RMS is variable. Unregulated sugar levels over a long period of time can lead to a shortened lifespan.
Donohue syndrome (leprechaunism) is a more severe form of INSR-related syndromic insulin resistance. Symptoms are similar to those seen in RMS, but are more serious. Most children with Donohue syndrome die before one year of age. Type A insulin resistance syndrome (type A) is a milder form of INSR-related syndromic insulin resistance. People with type A are often not diagnosed until their teens.
For more information, visit GARD.