"pernicious anemia." YourDictionary, n.d. Web. 16 October 2018. <http://www.yourdictionary.com/pernicious-anemia>.
pernicious anemia. (n.d.). Retrieved October 16th, 2018, from http://www.yourdictionary.com/pernicious-anemia
A severe anemia most often affecting older adults, caused by failure of the stomach to absorb vitamin B12 and marked by a decrease in number and an increase in the size of red blood cells, by gastrointestinal disturbances, and by lesions of the spinal cord.