Usually if the hematocrit reaches 30mm/h, this condition usually has the following diseases: First, the most common disease is rheumatism, for example, rheumatoid arthritis, rheumatoid arthritis can lead to an increase in the erythrocyte sedimentation rate, so the most common disease with a hematocrit of 30mm/h is rheumatism. Second, in the case of inflammatory infections, especially acute bacterial inflammatory infections, hematocrit 30mm/h will also occur. Third, in the case of active tuberculosis, when the body is infected with tuberculosis bacteria, there will also be hematocrit 30mm/h, or even more than 30mm/h. Fourthly, in the case of malignant tumor, the blood sedimentation will increase and accelerate with the malignant tumor, and then the blood sedimentation will also appear higher than 30mm/h or even more. Fifth, various causes of hyperglobulinemia, such as multiple myeloma, may also appear a transient increase in hematocrit.