At Patient Worthy, we are dedicated to stories about the latest in rare disease news and research, as well as posting stories from rare disease patients themselves. However, there are thousands of rare diseases that barely ever make the news. This is often simply because there is limited awareness about them and very little research or drug development is being conducted. This can leave patients with these diseases feeling the way that many rare patients do: left behind and ignored.
The counteract this trend in which certain rare diseases tend to get more of the spotlight, we will occasionally post stories that provide valuable information about rare illnesses and conditions that haven’t made the news lately. In this story, we will be looking at POMC deficiency obesity.
Proopiomelanocortin (POMC) deficiency obesity is a rare genetic disorder which causes obesity at a very early age. Only about 50 cases have been reported so far, so it is incredibly rare. It is also characterized by reduced levels of adrenocorticotropic hormone (ACTH). Many people with the disorder have pale skin and red hair. As the name of the illness suggests, the disorder is linked to mutations of the POMC gene. The protein that this gene is responsible for producing is normally subdivided into smaller pieces called peptides. The activity of these peptides, which include ACTH, must be balanced in a precise manner in order to regulate appetite and weight gain normally.
With this balance thrown off by a mutation, babies that are born with the disorder have a constant and voracious appetite. They feed excessively and most patients are already severely obese by their first year of life. Patients continue to experience excessive hunger throughout their lives and continue to be obese without treatment. As little research has been done on POMC deficiency obesity, it is unclear if patients are susceptible to typical health problems associated with obesity, such as diabetes and cardiovascular disease.
Another serious complication that often appears with POMC deficiency obesity is adrenal insufficiency, a condition in which the adrenal glands do not produce enough hormones. This is triggered by the reduced concentration of ACTH in patients. Adrenal insufficiency can cause blood sugar levels to drop severely, elevated levels of toxic bilirubin in the blood, reduced ability to produce bile, and seizures. Adrenal insufficiency is potentially fatal and should be treated promptly.
The rarity of the illness means that there is no standard treatment approach and no approved drugs that address the underlying cause. Management is therefore mostly symptomatic. Adrenal insufficiency should be treated with hydrocortisone.
To learn more about POMC deficiency obesity, click here.