Vitamin B12 is essential for proper neurological functioning, and its deficiency may cause a wide range of neuropsychiatric and hematological manifestations. We report a case of a previously healthy 32-year-old female who was admitted to our hospital with sudden onset of bilateral lower limb paraparesis and loss of sensation. The serum level of vitamin B12 was mildly decreased with high methylmalonic acid and homocysteine levels. However, her complete blood count showed no evidence of anemia or macrocytosis; instead, her mean corpuscular volume was low. Hemoglobin electrophoresis showed thalassemia trait, and that probably masked the megaloblastic features of vitamin B12 deficiency. She responded fully to vitamin B12 replacement therapy.

The Journal of Blood Medicine is an international, peer-reviewed, open access, online journal publishing laboratory, experimental and clinical aspects of all aspect pertaining to blood based medicine including but not limited to: Transfusion Medicine; Blood collection, Donor issues, Transmittable diseases, and Blood banking logistics; Immunohematology; Artificial and alternative blood based therapeutics; Hematology; Biotechnology/nanotechnology of blood related medicine; Legal aspects of blood medicine; Historical perspectives. The manuscript management system is completely online and includes a very quick and fair peer-review system. Visit http://www.dovepress.com/testimonials.php to read real quotes from published authors.