Neurological and Cardiovascular Complications Revealing Biermer's Disease: A Case Report

Biermer's disease (BD) or pernicious anemia (PA) is an autoimmune atrophic gastritis characterized by the absence of intrinsic factor (IF) secretion, leading to malabsorption of vitamin B12 in the ileum. Its clinical manifestations are primarily hematological, with neuropsychiatric and cardiovascular manifestations being less common. We present the case of a patient with PA diagnosed based on neurological and cardiovascular complications. The patient, a 56-year-old man with no specific medical history, presented with an episode of melena without other associated digestive symptoms. He also complained of memory and gait disturbances. Clinical examination revealed a cerebellar ataxia with impaired proprioceptive and vibratory sensitivity, and a swollen and red right lower limb with a positive Homan sign. The blood count showed macrocytic anemia. Gastroscopy revealed flattened fundic folds resembling a fundus appearance, and histopathological examination confirmed fundic atrophic gastritis with pseudopyloric metaplasia and lymphoplasmacytic infiltration. Anti-intrinsic factor antibodies were positive, while anti-parietal cell antibodies were negative. Vitamin B12 levels were severely low, and vitamin B9 levels were normal. TSH and HbA1c levels were within normal ranges. The abdominal CT scan showed no abnormalities. Lower limb Doppler ultrasound confirmed the diagnosis of deep vein thrombosis (DVT). Cardiac evaluation revealed sinus bradycardia suggestive of secondary dysautonomia. Therapeutically, the patient was started on vitamin B12 supplementation and anticoagulant therapy for DVT, resulting in a good clinical and biological outcome.