Insulin, Insulin Everywhere: A Rare Case Report of Rabson-Mendenhall Syndrome.

Rabson-Mendenhall syndrome (RMS) is a rare autosomal recessive disorder characterized by severe insulin resistance, a condition in which the body's tissues and organs do not respond appropriately to the hormone insulin. Insulin resistance impairs blood sugar regulation and ultimately leads to diabetes mellitus. A 19-year-old male presented with joint pain, blurring of vision, and generalized weakness. Investigations revealed hyperglycemia (random blood sugar (RBS) > 625 mg/dL, glycosylated hemoglobin (HbA1c) 18%), as well as sugars, protein, and ketone bodies in urine routine examination. An ultrasound of the abdomen was normal. Cardiac status was normal. Based on the clinical features, particularly the head to toe examination, skin changes, and the onset of type 2 diabetes mellitus, RMS syndrome was considered. The joint pain was alleviated with intravenous tramadol. Actrapid®, a fast-acting insulin, was given to control sugar levels, along with metformin. Vitamin B12 and pregabalin were also supplemented. A dermatological cream containing ammonium chloride, calcium lactate, glycerin, potassium chloride, sodium dihydrogen phosphate, and urea was given for skincare. It is an extremely rare disease with a frequency of fewer than one million people worldwide. Most patients survive only up to 15 years of age, although some can live into their third decade of life. Hepatic gluconeogenesis and fatty acid oxidation are affected, leading to ketoacidosis. The progression is much faster in RMS. In RMS, the genetic defect affects the insulin receptor (INSR) gene transcription with non-sense mutations and causes splicing defects. This results in premature chain termination and eventually to lower amounts of the insulin receptor messenger ribonucleic acid (mRNA). Ultimately, the number and density of insulin receptors in the plasma membrane are smaller, making the cells resistant to insulin. Herein, we report the case of a 19-year-old patient with RMS who was treated in our hospital, leading to a successful improvement in symptoms and discharge of the patient.