Combination of Vitamin B₁₂-Deficiency Anemia and Autoimmune Hemolytic Anemia: Is the Diagnosis Always Straightforward?
E.N. Belousova, A.V. Kosterina, M.S. Shashina, L.R. Sadykova
ABSTRACT. This article presents a clinical observation illustrating the differential diagnosis between the true combination of B12-deficiency pernicious anemia (PA) and autoimmune hemolytic anemia and the phenomenon of “pseudo-hemolysis.” A 71-year-old female patient with verified PA against a background of autoimmune atrophic gastritis and concomitant autoimmune thyroiditis was found to have macrocytic anemia, hyperbilirubinemia, elevated lactate dehydrogenase (LDH), and a positive direct Coombs test (DAT) with negative anti-erythrocyte antibodies. The key criterion was the reticulocyte production index (RPI = 1.38), indicating ineffective erythropoiesis characteristic of PA rather than true hemolysis. Cyanocobalamin monotherapy caused a reticulocyte crisis, decreased LDH and bilirubin, and increased hemoglobin, confirming the false-positive nature of the DAT. The authors conclude that a positive Coombs test in PA does not require the administration of glucocorticosteroids; correct interpretation allows avoiding unnecessary immunosuppression.
For citation: Belousova EN, Kosterina AV, Shashina MS, Sadykova LR. Combination of vitamin B₁₂-deficiency anemia and autoimmune hemolytic anemia: Is the diagnosis always straightforward? Therapy (Moscow). 2026;12(5S):138–142.
https://doi.org/10.18565/therapy.2026.5-s5.138-142
Ключевые слова
B₁₂-deficiency anemia
hemolysis
pseudo-hemolysis
reticulocytes
direct Coombs test
autoimmune hemolytic anemia
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Об авторах / Для корреспонденции
Elena N. Belousova, MD, PhD (Medicine), assistant at the Department of hospital therapy, Kazan State Medical University, Kazan, Russian Federation.E-mail: elene-n-belousova@yandex.ru
ORCID: https://orcid.org/0000-0001-9369-4993. Scopus ID: 57192694957. eLibrary SPIN: 8775-6434
Anna V. Kosterina, MD, assistant at the Department of hospital therapy, Kazan State Medical University, Kazan, Russian Federation.
E-mail: avakost@mail.ru
ORCID: https://orcid.org/0000-0002-4171-0661
Mariia S. Shashina, 6th-year student Kazan State Medical University, Kazan, Russian Federation.
E-mail: shashina.maria@mail.ru
ORCID: https://orcid.org/0009-0009-3945-8653
Leila R. Sadykova, gastroenterologist at the Republican Clinical Hospital, Kazan, Russian Federation.
E-mail: s.leila87@icloud.com
ORCID: https://orcid.org/0000-0002-7514-9577
