The MuLBSTA score is a tool designed to estimate the risk of 90-day mortality for patients with viral pneumonia. The scoring process considers six clinical parameters: multilobe infiltrate, absolute lymphocyte count, bacterial coinfection, smoking history, hypertension, and age. Each of these factors is assigned a score based on their presence.

Here's how each factor is scored:

- **Multilobe infiltrate**: 
  - Yes: 5 points
  - No: 0 points
- **Absolute lymphocyte count <= 0.8×10^9/L**:
  - Yes: 4 points
  - No: 0 points
- **Bacterial coinfection**:
  - Yes: 4 points
  - No: 0 points
- **Smoking history**:
  - Non smoker: 0 points
  - Prior smoker: 2 points
  - Active smoker: 3 points
- **Hypertension**:
  - Yes: 2 points
  - No: 0 points
- **Age >= 60 years**:
  - Yes: 2 points
  - No: 0 points

To calculate the MuLBSTA score, accumulate the points from each of the patient's responses according to the criteria above. The total score, which ranges from 0 to 20, provides an estimation of the patient's risk of 90-day mortality.

Interpret the total score as follows:

- 0 points: Risk of 90-day mortality is 0.47%
- 2 points: Risk of 90-day mortality is 0.87%
- 3 points: Risk of 90-day mortality is 1.18%
- 4 points: Risk of 90-day mortality is 1.60%
- 5 points: Risk of 90-day mortality is 2.17%
- 6 points: Risk of 90-day mortality is 2.92%
- 7 points: Risk of 90-day mortality is 3.93%
- 8 points: Risk of 90-day mortality is 5.27%
- 9 points: Risk of 90-day mortality is 7.03%
- 10 points: Risk of 90-day mortality is 9.33%
- 11 points: Risk of 90-day mortality is 12.27%
- 12 points: Risk of 90-day mortality is 15.99%
- 13 points: Risk of 90-day mortality is 20.56%
- 14 points: Risk of 90-day mortality is 26.03%
- 15 points: Risk of 90-day mortality is 32.36%
- 16 points: Risk of 90-day mortality is 39.42%
- 17 points: Risk of 90-day mortality is 46.95%
- 18 points: Risk of 90-day mortality is 54.61%
- 19 points: Risk of 90-day mortality is 62.07%
- 20 points: Risk of 90-day mortality is 68.99%

This scoring system enables healthcare providers to estimate and categorize the risk of mortality, aiding in clinical decision-making and potentially guiding patient management.

The MuLBSTA score is a clinical calculator used to predict the mortality risk in patients with viral pneumonia. The name "MuLBSTA" is an acronym derived from the six parameters it assesses: Multilobular infiltrates, Lymphopenia, Bacterial co-infection, Smoking history, Hypertension, and Age. 

This scoring system is specifically applicable to patients diagnosed with viral pneumonia, including but not limited to those caused by influenza viruses and SARS-CoV-2 (COVID-19). 

The clinical utility of the MuLBSTA score lies in its ability to stratify patients based on their risk of mortality. This can guide clinicians in making decisions about the level of care required, including hospital admission, intensive care unit transfer, and the need for mechanical ventilation. 

There are no specific exclusion criteria for the use of the MuLBSTA score. However, it should be noted that this score may not be as accurate in patients with non-viral pneumonia or those with incomplete clinical data.

MuLBSTA score for viral pneumonia mortality