Patient presents with symptoms suggestive of pernicious anemia, including fatigue, weakness, and shortness of breath.  The patient also reports glossitis, paresthesia, and difficulty with balance.  Physical examination reveals pallor and a smooth, red tongue.  Laboratory findings demonstrate macrocytic anemia with an elevated mean corpuscular volume (MCV).  Vitamin B12 levels are significantly decreased.  Intrinsic factor antibody (IFA) and anti-parietal cell antibody tests were ordered to confirm the diagnosis of pernicious anemia.  The patient's symptoms, combined with the laboratory results, including low B12 and positive antibody tests (if applicable), indicate a deficiency of intrinsic factor, leading to impaired vitamin B12 absorption.  Differential diagnosis includes other causes of macrocytic anemia such as folate deficiency and myelodysplastic syndromes.  Treatment plan includes intramuscular vitamin B12 injections to address the B12 deficiency.  Patient education regarding the chronic nature of pernicious anemia and the need for ongoing B12 replacement therapy was provided.  Follow-up appointments are scheduled to monitor B12 levels, hematological response, and neurological symptoms.  ICD-10 code D51.0 (pernicious anemia) is documented for medical billing and coding purposes.  CPT codes for vitamin B12 injections and laboratory tests are also documented as appropriate.  The patient was advised to follow a healthy diet and report any new or worsening symptoms. Prognosis discussed with the patient.