Pancytopenia and TTP-like picture secondary to pernicious anaemia

Abstract

<jats:p>A 21-year-old man presented to the emergency department with generalised weakness, weight loss and decreased appetite for few weeks. He had evidence of severe pancytopenia and haemolysis. His peripheral smear with many schistocytes was suspicious for thrombotic thrombocytopenic purpura (TTP). He was supported with blood transfusions and daily plasmapheresis. His platelet counts worsened despite 4 days of therapy. Bone marrow biopsy was significant for hypercellular bone marrow with megaloblastic changes. Further workup revealed normal ADAMTS13 level, low vitamin B<jats:sub>12</jats:sub>, positive intrinsic factor antibodies and high methylmalonic acid. Diagnosis of pernicious anaemia was established and he was started on daily treatment with intramuscular vitamin B<jats:sub>12</jats:sub> which subsequently improved his symptoms and haematological parameters. This report highlights the importance of checking vitamin B<jats:sub>12</jats:sub> level in patients presenting with pancytopenia and TTP-like picture before making a diagnosis of TTP.</jats:p>

Life-Threatening Microangiopathy or Vitamin Deficiency: A Case Report of the Clinical Manifestations of Pseudo-Thrombotic Microangiopathic Anemia

“…Noel et al [5] compared patients with pseudo-TMA to patients with TTP and found that pseudo-TMA patients had higher median lactate dehydrogenase (LDH) levels, lower reticulocyte counts, and higher platelet counts. Similar evaluations by Chen et al [6] further subdivided patients with pseudo-TMA secondary to pernicious anemia and studied their common characteristics. They found that 61.5% (eight of 13) of the current patients identified in the literature had severely elevated levels of LDH.…”

Concomitant Vitamin B1 and Vitamin B12 Deficiency Mimicking Thrombotic Thrombocytopenic Purpura

“…Pseudo-TTP is treated by correcting the underlying condition, so accurate diagnosis and knowledge of this condition are essential. Differential diagnoses of pseudo-TTP with cytopenias include vitamin B12 deficiency, myelodysplastic syndrome, drug-induced TTP (including cocaine), and connective tissue disorders such as SLE [ 4 ]. With serological workup, drug screen, and bone marrow biopsy, we ruled out these alternate etiologies in our patient.…”

“…In contrast, a more recent retrospective cohort study by Koshy et al on 2,669 patients with vitamin B12 deficiency reported that the prevalence could be as low as 0.6% [ 3 ]. The majority of the pseudo-TTP in vitamin B12 deficit in the previously reported studies and case reports was secondary to pernicious anemia (65%-70%), and secondary to nutritional deficiency was a small subset [ 1 , 3 , 4 ]. Hence in the majority of cases (65%-70% with Pernicious anemia), treatment with B12 would suffice.…”

“…Some characteristics included a high LDH, high bilirubin, hypersegmented neutrophils, low reticulocyte index, low to medium plasmic score, schistocytes, and teardrop cells on peripheral smear, etc. [ 3 , 4 ]. Our patient’s labs were in alignment with these diagnostic criteria.…”

“…Prompt recognition of the condition and treatment with parenteral B12 replacement is essential. Most reported vitamin B12 deficiency-induced pseudo-TTP cases in the literature are secondary to pernicious anemia, which is antibody-mediated disruption of B12 absorption [ 1 , 3 , 4 ]. We would like to highlight that in contrast to the majority of reported cases of vitamin B12- associated pseudo-TTP, which were from pernicious anemia, our patient had possible nutritional vitamin B12 deficiency along with vitamin B1 (thiamine) deficiency.…”