A high immature granulocyte ratio of 1.8 indicates that a bacterial infection, acute blood loss, or hematologic disease may have occurred. 1. Bacterial infection: When severe bacterial infection occurs, mature granulocytes will migrate to the site of infection, resulting in the presence of immature granulocytes in the blood and a high immature granulocyte ratio in routine blood tests. 2. Acute blood loss: If there is acute blood loss, it may lead to blood dilution, causing rapid increase of white blood cells, resulting in high immature granulocyte ratio. 3. Hematologic diseases: When the patient has acute myeloid leukemia, it causes immature granulocytes to proliferate in the bone marrow and be released into the peripheral blood, resulting in a high immature granulocyte ratio. If the immature granulocyte ratio is high, it is necessary to go to the hospital in time to consult the doctor, to clarify the cause of the disease, and then follow the doctor’s instructions for treatment.