The French MITS score calculator is a tool designed to predict the risk of in-hospital mortality for patients with thrombotic thrombocytopenic purpura (TTP) through seven clinical factors. Here's how it works:

1. **Inputs and Scoring**: The calculator uses seven yes-or-no questions based on the patient's clinical status:
   - Age 60 years or older: 2 points
   - Platelet transfusion: 1 point
   - Acute or chronic renal failure, or need for hemodialysis: 1 point
   - Myocardial infarction: 1 point
   - Ischemic stroke: 1 point
   - Central nervous system hemorrhage: 3 points
   - Arterial thrombosis: 3 points

2. **Score Calculation**: Each affirmative answer adds the corresponding points for that factor. The total score is the sum of these points and can range from 0 to 12.

3. **Interpreting the Score**:
   - Score of 0: The risk of in-hospital mortality is 0.72%.
   - Score of 1: The risk is 5.47%.
   - Score of 2: The risk is 8.33%.
   - Score of 3: The risk is 19.6%.
   - Score of 4: The risk is 26.67%.
   - Score of 5: The risk is 35.36%.
   - Score of 6: The risk is 60%.
   - Score of 7 or higher: The risk is greater than 60%.

Using these scores, medical professionals can assess the severity and mortality risk of TTP in a structured way, guiding informed decisions about patient care.

The French mortality score in thrombotic thrombocytopenic purpura, also known as the MITS score, is a clinical tool designed to predict in-hospital mortality in patients diagnosed with thrombotic thrombocytopenic purpura. The score is calculated based on seven key components: age equal to or greater than 60 years, platelet transfusion, acute or chronic renal failure or need of hemodialysis, myocardial infarction, ischemic stroke, central nervous system hemorrhage, and arterial thrombosis. Each component contributes to the overall score, which ranges from 0 to 7 or more. 

The MITS score provides a quantitative measure of mortality risk, with higher scores indicating a greater risk. For instance, a score of 0 corresponds to a 0.72% risk of in-hospital mortality, while a score of 7 or more corresponds to a risk greater than 60%. This scoring system allows clinicians to stratify patients based on their risk and guide clinical decision-making accordingly.

French mortality score in thrombotic thrombocytopenic purpura (MITS score)

Prognostic risk-stratified score for predicting mortality in hospitalized patients with thrombotic thrombocytopenic purpura: nationally representative data from 2007 to 2012.