ABSTRACT
BACKGROUND: Infectious mononucleosis is one of the main manifestations of Epstein - Barr virus, which is characterized by fever, tonsillar-pharyngitis, lymphadenopathy and atypical lymphocytes. Although 60% of patients with IMN develop cold type antibodies, clinically significant hemolytic anemia with a high ferritin level is very rare and validity of serum ferritin as an important biomarker has not been used frequently. CASE PRESENTATION: 18-year-old girl presented with fever, malaise and sore throat with asymptomatic anemia, generalized lymphadenopathy, splenomegaly and mild hepatitis. Investigations revealed that she had cold type autoimmune hemolysis, significantly elevated serum ferritin, elevated serum lactate dehydrogenase level with serological evidence of recent Epstein Barr infection. She was managed conservatively and her hemoglobin and serum ferritin levels normalized without any intervention following two weeks of the acute infection. CONCLUSION: Cold type autoimmune hemolytic anemia is a rare manifestation of infectious mononucleosis and serum ferritin is used very rarely as an important biomarker. Management of cold type anemia is mainly supportive and elevated serum ferritin indicates severe viral disease.