Drew and Boyle developed the RUWA (ratio, urea, WBC, albumin) scoring system for evaluating a patient with Clostridium difficile colitis. The authors are from St. James's Hospital in Dublin.
Parameters:
(1) ratio of the white blood cell count on the day of first positive C. difficile toxin test to the white blood cell count 2 days previously
(2) urea in mmol/L on the day of the positive toxin test
(3) white blood cell count on the day of the positive toxin test
(4) serum albumin in g/L on the day of the positive toxin test
|
Parameter |
Finding |
Points |
|---|---|---|
|
WBC ratio |
0 to 0.49 |
1 |
|
|
0.50 to 1.50 |
0 |
|
|
1.51 to 2.00 |
1 |
|
|
2.01 to 4.00 |
2 |
|
|
> 4.00 |
3 |
|
urea |
< 10 mmol/L |
0 |
|
|
10 to 20 mmol/L |
1 |
|
|
> 20 mmol/L |
2 |
|
white blood cell count |
< 4 * 10^9/L |
1 |
|
|
4 to 10 * 10^9/L |
0 |
|
|
10.1 to 20 * 10^9/L |
1 |
|
|
20.1 to 30 * 10^9/L |
2 |
|
|
> 30 * 10^9/L |
3 |
|
serum albumin |
> 30 g/L |
0 |
|
|
24 to 30 g/L |
1 |
|
|
< 24 g/L |
2 |
where:
• Patients were in an enhanced surveillance program so toxin testing was done promptly in a person with a compatible clinical picture.
total score =
= SUM(points for all 4 parameters)
Interpretation:
• minimum score: 0
• maximum score: 10
• A score >= 4 is associated with risk of severe complications.
Performance:
• The sensitivity was 80% and specificity 77% on day 1 of active surveillance.
• The sensitivity was 63% and specificity 82% on day 3 of active surveillance.
• If a person is evaluated on days 1 and 3, the sensitivity was 100% and specificity 70%.
• The negative predictive value was high so a person identified as low risk is unlikely to have serious complications.
Purpose: To evaluate a patient with Clostridium difficile colitis using the RUWA scoring system of Drew and Boyle.
Specialty: Infectious Diseases, Gastroenterology
Objective: risk factors, severity, prognosis, stage, complications
ICD-10: A04.7,
