The McMahon Score calculator estimates the risk of kidney failure or mortality in individuals with rhabdomyolysis, considering a combination of clinical and demographic factors. The calculator processes input across eight specific areas:

1. **Age (years)**
   - <= 50: 0 points
   - 51-70: 1.5 points
   - 71-80: 2.5 points
   - > 80: 3 points

2. **Sex**
   - Male: 0 points
   - Female: 1 point

3. **Initial creatinine (mg/dL)**
   - < 1.4: 0 points
   - 1.4-2.2: 1.5 points
   - > 2.2: 3 points

4. **Initial calcium (mg/dL)**
   - < 7.5: 2 points
   - >= 7.5: 0 points

5. **Initial creatine phosphokinase (U/L)**
   - > 40,000: 2 points
   - <= 40,000: 0 points

6. **Cause of rhabdomyolysis (secondary to seizures, syncope, exercise, statins, or myositis)**
   - Yes: 0 points
   - No: 3 points

7. **Initial phosphate (mg/dL)**
   - < 4.0: 0 points
   - 4.0-5.4: 1.5 points
   - > 5.4: 3 points

8. **Initial bicarbonate**
   - < 19 mEq/L: 2 points
   - > 19 mEq/L: 0 points

To calculate the total score, each selected option is transformed into a numerical value as per the above scale, then aggregated to produce a score ranging from 0 to 19. 

The interpretation of the total score is straightforward:

- A score less than 6 indicates a low risk of death or acute kidney injury requiring renal replacement therapy.
- A score of 6 or higher denotes a high risk of these adverse outcomes. 

This score helps guide clinical decisions, highlighting the urgency and level of intervention required based on risk.

The McMahon score is a clinical tool designed for predicting kidney failure or mortality in patients with rhabdomyolysis. The primary components of the McMahon score include patient's age, sex, initial creatinine, initial calcium, initial creatine phosphokinase, whether the rhabdomyolysis is secondary to seizures, syncope, exercise, statins, or myositis, initial phosphate, and initial bicarbonate. Each of these components is assigned a specific value based on the patient's condition, and the total score is used to estimate the risk of kidney failure or mortality. The McMahon score is particularly useful in guiding clinical decision-making and patient management in cases of rhabdomyolysis.

McMahon score for kidney failure or mortality in rhabdomyolysis