A 27-year-old female presents with easy fatigue and light-headedness. She also has a dry cough and fever for the past few days. On examination, she is pale, her lungs are clear, and the rest is normal. A chest x-ray (CXR) shows patchy bilateral infiltrates; the hemoglobin is 8.4 g/dL, reticulocyte count of 6%, and many spherocytes on the peripheral blood film. Which of the following is the most likely significance of the spherocytosis on the blood film?

Spherocytes are seen on the blood film in patients with moderate to severe hemolytic anemia. This patient has autoimmune hemolytic anemia due to cold agglutinins related the pneumonia. Spherocytosis is not associated with G6PD deficiency, trauma, or leukemia. The typical changes in G6PD deficiency include the presence of Heinz bodies. The cell morphology is not usually changed unless hemolysis is very severe. In hereditary spherocytosis, the Coombs' test is negative.