Yes, there is such a thing as pyruvate kinase deficiency. I am not a physician but a medical student. No one on this board (myself included) can diagnose your grandson with pyruvate kinase deficiency or your daughter-in-law with bipolar disorder. So this is FYI only: pyruvate kinase deficiency would necessitate frequent blood transfusions in more serious cases. Basically, pyruvate kinase is an enzyme that is used by red blood cells, and without it, the red blood cells break down very easily; hence, the need for frequent transfusions.
Rather than listen to a stranger from a web board, however, for this type of question, I would encourage you to speak to your son and daughter-in-law, and perhaps your own physician, about your concerns. Pyruvate kinase deficiency, bipolar disorder, and Munchausen-by-Proxy are not disorders to be taken lightly!
Co-moderator - IBS Forum
Please always remember to consult your medical professional regarding your medical questions; this forum is intended to provide patient-to-patient support. Although some of us have healthcare backgrounds, we cannot diagnose or treat patients on the board.