- The LYM% (blood lymphocyte percentage) can be used as a reliable indicator to classify the infection as moderate, severe and critical independently of any other auxiliary indicators.
- TML (Time-LYM%-model) is a tool of classification and prognosis prediction. TML-1 is defined as the LYM% at day 10-12 after symptom onset and TML-2 is the LYM% at day 17-19 after symptom onset.
- TML-1: LYM% > 20 % are classified moderate and can recover quickly, otherwise it’s classified as severe and may need medical attention.
- TML-2: LYM% >20% are classified as in recovery, 5% < LYM% <20% are still in danger and need supervision, and LYM% <5% are critically ill with high mortality rate and need intensive care.
This figure was taken from https://www.nature.com/articles/s41392-020-0148-4#Fig1 and is published under an open access license.
The TML was created with the analysis of 12 random death cases, 7 random cases severe infection and 11 random cases of moderate infection. The TML was afterward validated using 90 hospitalized patients. All the patients come from China.
Tan L., Wang Q., Zhang D., et al. (March 27, 2020). Lymphopenia predicts disease severity of COVID-19: a descriptive and predictive study. Nature. https://doi.org/10.1038/s41392-020-0148-4