Pernicious Anemia and Vitamin B12 Deficiency Presenting As Pseudothrombotic Microangiopathy and Developing Secondary Thrombocytopenia After Treatment: A Case Report

Abstract

Pernicious anemia (PA) is an autoimmune disease secondary to chronic atrophic gastritis leading to vitamin B12 deficiency. Rarely, some patients may develop advanced hematological complications that mimic those of thrombotic thrombocytopenic purpura (TTP). Differentiating these conditions is crucial because they require different management. We present a case of a 68-year-old male who presented with generalized weakness, fatigue, and shortness of breath. This patient had anemia, thrombocytopenia, and a markedly deficient serum level of vitamin B12. The symptoms initially mimicked those associated with TTP, but the activity of ADAMTS 13 was normal. A diagnosis of pseudo-TTP has been made due to vitamin B12 deficiency resulting from PA with reactive thrombocytosis. Ultimately, vitamin B12 deficiency pseudo-TTP should be considered a differential diagnosis for therapy refractory TTP because of its different management strategies ranging from parenteral Vitamin B12 in PA patients with highly favorable outcomes to more advanced treatment with less favorable outcomes in TTP patients.

Pernicious Anemia Unveiled: Unusual Hemolytic Complications and Clinical Implications

“…This case describes a patient with untreated PA who presented with significant gastritis and hemolytic anemia, highlighting pseudo-TMA as a rare but significant hematological complication of PA. Distinguishing TMA secondary to PA from true TMA presents a challenging scenario, particularly given the rarity of pseudo-TMA and the similarities in clinical presentation between these two conditions, like hemolytic anemia, thrombocytopenia, and schistocytosis [ 6 ]. In clinical practice, distinguishing between pseudo-TMA due to PA and true TMA is critical because their treatments are different.…”

“…This underscores the importance of considering PA-associated vitamin B12 deficiency in the differential diagnosis when encountering conditions with similar hematological manifestations. There have been several other cases examining hemolytic anemia in patients with vitamin B12 deficiency [ 6 - 13 ]. In some of these cases, further investigation revealed positive anti-IF antibodies, which confirmed the diagnosis of PA-associated pseudo-TMA [ 6 , 8 - 10 ].…”

“…There have been several other cases examining hemolytic anemia in patients with vitamin B12 deficiency [ 6 - 13 ]. In some of these cases, further investigation revealed positive anti-IF antibodies, which confirmed the diagnosis of PA-associated pseudo-TMA [ 6 , 8 - 10 ].…”

“…Distinguishing TMA secondary to PA from true TMA presents a challenging scenario, particularly given the rarity of pseudo-TMA and the similarities in clinical presentation between these two conditions, like hemolytic anemia, thrombocytopenia, and schistocytosis [6]. In clinical practice, distinguishing between pseudo-TMA due to PA and true TMA is critical because their treatments are different.…”

Research Progress of Cuttlebone in the Treatment of Chronic Atrophic Gastritis

“…Some patients with CAG have no obvious discomfort in clinical manifestations, but most patients will have upper abdominal burning pain, swelling pain, aggravation after eating, poor appetite, nausea, acid reflux [3], and other gastrointestinal symptoms. Patients with severe symptoms will have anemia [4]. CAG is often accompanied by different degrees of intestinal metaplasia or atypical hyperplasia.…”