Anemia Causes More Condition_symptoms What Causes Symptoms In Pernicious Anemia?

What causes symptoms in pernicious anemia? - anemia causes more condition_symptoms

I am looking for information on why the biochemistry of pernicious anemia causes, symptoms such as sore tongue, dysphagia, and abdominal pain. I know that this is due to a lack of vitamin B12, but how do I extend the symptoms I just mentioned? Please cite references, if you know. I'm searching online for an hour with no luck. Thank you very much, and 10 points for the best answer.