Final answer:
A potentially fatal complication of Graves disease is thyroid storm, which is a severe form of hyperthyroidism with symptoms that can lead to multiple organ failure and death without prompt treatment.
Step-by-step explanation:
A potentially fatal complication of Graves disease is the development of a severe form of hyperthyroidism known as thyroid storm. Thyroid storm is characterized by exaggerated hyperthyroid symptoms such as fever, jaundice, hypotension, and disseminated intravascular coagulation, which can lead to multiple organ failure and possibly death if not treated promptly. Due to the nature of Graves disease, wherein the immune system produces thyroid-stimulating immunoglobulin, this condition can excessively stimulate the thyroid to produce large amounts of thyroid hormones, thus precipitating a thyroid storm.
Graves disease also causes an increase in basal metabolic rate (BMR), weight loss, increased heart rate, and inability to sleep. Another notable symptom of Graves disease is exophthalmia, or Graves ophthalmopathy, which involves bulging of the eyes. While not typically fatal, severe cases of exophthalmia can cause vision impairment and pressure on the optic nerve.
It is critical for individuals with Graves disease to be closely monitored and treated to prevent such severe complications like thyroid storm, which can be fatal if not properly managed.