PERNICIOUS ANEMIA PRESENTING WITH MICROANGIOPATHY AND MULTI-ORGAN FAILURE

Abstract

SESSION TITLE: Tuesday Fellows Case Report Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/22/2019 01:00 PM - 02:00 PM INTRODUCTION: Pernicious anemia may rarely present with serious life threatening pseudo-thrombotic microangiopathy and can be a diagnostic challenge. CASE PRESENTATION: A 46-year-old female presented to the hospital after she sustained a fall. She had abdominal distension without associated diarrhea, constipation, vomiting, fevers, cough or shortness of breath. Initially, she was afebrile but hypotensive, tachycardic and stuporous. No signs of meningitis were noticed. Arterial blood gas revealed acute hypoxemic and hypercarbic respiratory failure, and she was promptly intubated. Her blood work revealed hemoglobin of 3.1g/dL with MCV of 127.6, white cell count of 2.9x103/mcl, platelet count of 16x103/mcl and serum creatinine of 4.7. She went into severe acute respiratory distress syndrome with P/F ratio CT scan of the head did not show any acute abnormalities. Peripheral blood smear revealed macrocytic red cells with schistocytes, few target cells, tear drop cells and hypersegmented neutrophils. LDH was elevated at 1224 with extremely low haptoglobin of 9. Vitamin B12 level was low at 129 but with normal folate. Pernicious anemia was suspected, and she was started on therapeutic doses of vitamin B12 with rapid improvement in her blood counts. ADAMTS 13 level was found to be normal. Her hospital course was further complicated by a small right frontal lobe hemorrhage to the size of 1.5 cm and fungemia. Eventually, intrinsic factor blocking antibody and gastric parietal cell antibody came back positive thereby confirming the diagnosis. She had dramatic improvement in her clinical condition over the next week and was successfully extubated. DISCUSSION: Acute kidney injury in the setting of thrombocytopenia, altered mental status, elevated LDH with low haptoglobin and schistocytes are indicative of ongoing hemolysis. [1] However, presence of hypersegmented neutrophils with low vitamin B12 level and positive serology confirmed the diagnosis of pernicious anemia. Hemolysis in this setting suggested a rare entity called “pseudo” thrombotic microangiopathy.[2] This term is aptly used in this situation because cytoskeletal fragility in dyserythropoiesis from vitamin B12 deficiency leads to fragmentation of red cells and presents with anemia, thrombocytopenia, low fibrinogen, elevated D dimer, schistocytosis and multi-organ failure. This is very different from thrombotic thrombocytopenic purpura where schistocytes are formed as a result of fragmentation on fibrin strands. CONCLUSIONS: This is an unusual and severe presentation of pernicious anemia with life threatening multi-organ failure and ARDS. Reference #1: Scully M, Hunt BJ, Benjamin S, et al. Guidelines on the diagnosis and management of thrombotic thrombocytopenic purpura and other thrombotic microangiopathies. Br J Haematol 2012; 158(3): 323–335 Reference #2: Noel N, Maigne G, Tertian G, et al. Hemolysis and schistocytosis in the emergency department: consider pseudothrombotic microangiopathy related to vitamin B12 deficiency. QJM 2013; 106(11): 1017–1022. DISCLOSURES: No relevant relationships by Andrew Berman, source=Web Response No relevant relationships by Jasveen Kaur, source=Web Response No relevant relationships by Gurveen Malhotra, source=Web Response No relevant relationships by Amee Patrawalla, source=Web Response