From www.bloodjournal.org by guest on September 11, 2016. For personal use only.
bloodwork ®
IMAGES
IN HEMATOLOGY
Severe vitamin B12 deficiency mimicking thrombotic thrombocytopenic purpura
c Joshua K. Routh and Sara C. Koenig, University of New Mexico
A
previously healthy 43-year-old man with chronic alcoholism presented to a rural medical center with a 2-week history of confusion, fever, dyspnea, dizziness, and fatigue associated with diarrhea and hematochezia. Laboratory results were notable for a platelet count of 19 3 109/L, hemoglobin of 5.0 g/dL, hematocrit of 15.1%, white blood cell count of 3.2 3 109/L, a reticulocyte count of 5.9%, mean corpuscular volume of 118 fL, and normal creatinine. A peripheral blood smear was interpreted at the outside facility as having marked schistocytes. A diagnosis of presumed thrombotic thrombocytopenic purpura/hemolytic uremic syndrome was given. The patient was transfused with 3 units of plasma and transferred to a tertiary care hospital for therapeutic plasma exchange. A repeat peripheral blood smear showed a macrocytic anemia with increased anisopoikilocytosis, hypersegmented neutrophils, and marked thrombocytopenia consistent with megaloblastic anemia (see figure). Further testing revealed a decreased vitamin B12 level of 93 pg/mL with unremarkable iron studies. Although the patient’s profound thrombocytopenia was concerning, ADAMTS13 activity was measured at 71%, excluding thrombotic thrombocytopenic purpura. Additional workup was positive for intrinsic factor antibodies, confirming the diagnosis of pernicious anemia. Although the clinical presentation and degree of thrombocytopenia may be concerning for a microangiopathic process, careful review of the peripheral blood will help direct appropriate clinical management. Severe megaloblastic anemia may cause marked anisopoikilocytosis with bizarre microcytes and thrombocytopenia. These findings should not be confused with microangiopathic hemolytic anemia. For additional images, visit the ASH IMAGE BANK, a reference and teaching tool that is continually updated with new atlas and case study images. For more information visit http://imagebank.hematology.org. © 2014 by The American Society of Hematology 1844
BLOOD, 11 SEPTEMBER 2014 x VOLUME 124, NUMBER 11
From www.bloodjournal.org by guest on September 11, 2016. For personal use only.
2014 124: 1844 doi:10.1182/blood-2014-03-562488
Severe vitamin B12 deficiency mimicking thrombotic thrombocytopenic purpura Joshua K. Routh and Sara C. Koenig
Updated information and services can be found at: http://www.bloodjournal.org/content/124/11/1844.full.html Articles on similar topics can be found in the following Blood collections BloodWork (465 articles) Free Research Articles (4037 articles) Red Cells, Iron, and Erythropoiesis (728 articles) Information about reproducing this article in parts or in its entirety may be found online at: http://www.bloodjournal.org/site/misc/rights.xhtml#repub_requests Information about ordering reprints may be found online at: http://www.bloodjournal.org/site/misc/rights.xhtml#reprints Information about subscriptions and ASH membership may be found online at: http://www.bloodjournal.org/site/subscriptions/index.xhtml
Blood (print ISSN 0006-4971, online ISSN 1528-0020), is published weekly by the American Society of Hematology, 2021 L St, NW, Suite 900, Washington DC 20036. Copyright 2011 by The American Society of Hematology; all rights reserved.
bloodwork ®
IMAGES
IN HEMATOLOGY
Severe vitamin B12 deficiency mimicking thrombotic thrombocytopenic purpura
c Joshua K. Routh and Sara C. Koenig, University of New Mexico
A
previously healthy 43-year-old man with chronic alcoholism presented to a rural medical center with a 2-week history of confusion, fever, dyspnea, dizziness, and fatigue associated with diarrhea and hematochezia. Laboratory results were notable for a platelet count of 19 3 109/L, hemoglobin of 5.0 g/dL, hematocrit of 15.1%, white blood cell count of 3.2 3 109/L, a reticulocyte count of 5.9%, mean corpuscular volume of 118 fL, and normal creatinine. A peripheral blood smear was interpreted at the outside facility as having marked schistocytes. A diagnosis of presumed thrombotic thrombocytopenic purpura/hemolytic uremic syndrome was given. The patient was transfused with 3 units of plasma and transferred to a tertiary care hospital for therapeutic plasma exchange. A repeat peripheral blood smear showed a macrocytic anemia with increased anisopoikilocytosis, hypersegmented neutrophils, and marked thrombocytopenia consistent with megaloblastic anemia (see figure). Further testing revealed a decreased vitamin B12 level of 93 pg/mL with unremarkable iron studies. Although the patient’s profound thrombocytopenia was concerning, ADAMTS13 activity was measured at 71%, excluding thrombotic thrombocytopenic purpura. Additional workup was positive for intrinsic factor antibodies, confirming the diagnosis of pernicious anemia. Although the clinical presentation and degree of thrombocytopenia may be concerning for a microangiopathic process, careful review of the peripheral blood will help direct appropriate clinical management. Severe megaloblastic anemia may cause marked anisopoikilocytosis with bizarre microcytes and thrombocytopenia. These findings should not be confused with microangiopathic hemolytic anemia. For additional images, visit the ASH IMAGE BANK, a reference and teaching tool that is continually updated with new atlas and case study images. For more information visit http://imagebank.hematology.org. © 2014 by The American Society of Hematology 1844
BLOOD, 11 SEPTEMBER 2014 x VOLUME 124, NUMBER 11
From www.bloodjournal.org by guest on September 11, 2016. For personal use only.
2014 124: 1844 doi:10.1182/blood-2014-03-562488
Severe vitamin B12 deficiency mimicking thrombotic thrombocytopenic purpura Joshua K. Routh and Sara C. Koenig
Updated information and services can be found at: http://www.bloodjournal.org/content/124/11/1844.full.html Articles on similar topics can be found in the following Blood collections BloodWork (465 articles) Free Research Articles (4037 articles) Red Cells, Iron, and Erythropoiesis (728 articles) Information about reproducing this article in parts or in its entirety may be found online at: http://www.bloodjournal.org/site/misc/rights.xhtml#repub_requests Information about ordering reprints may be found online at: http://www.bloodjournal.org/site/misc/rights.xhtml#reprints Information about subscriptions and ASH membership may be found online at: http://www.bloodjournal.org/site/subscriptions/index.xhtml
Blood (print ISSN 0006-4971, online ISSN 1528-0020), is published weekly by the American Society of Hematology, 2021 L St, NW, Suite 900, Washington DC 20036. Copyright 2011 by The American Society of Hematology; all rights reserved.
