Cowling et al reported two models for evaluating a patient with Severe Acute Respiratory Syndrome (SARS). The full model requires access to radiology and laboratory testing. The authors are from the University of Hong Kong, Mount Sinai Hospital (Toronto) and the Canadian SARS Research Network.
Patient selection: severe acute respiratory syndrome (SARS)
Outcome: mortality
Parameters:
(1) age in years
(2) sex
(3) number of comorbid conditions (asthma, COPD, cardiovascular disease, cerebrovascular disease, cancer, diabetes mellitus, chronic renal disease, chronic liver disease)
(4) chest radiograph
(5) oxygen saturation on room air in percent
(6) serum LDH relative to the upper limit of normal
(7) absolute neutrophil count relative to the upper and lower limit of normal
(8) platelet count relative to the lower limit of normal (thrombocytopenia)
(9) absolute lymphocyte count relative to the lower limit of normal (lymphopenia)
Parameter |
Finding |
Points |
age in years |
< 40 years |
0 |
|
40 to 49 years |
12 |
|
50 to 59 years |
16 |
|
60 to 69 years |
25 |
|
>= 70 years |
34 |
sex |
female |
0 |
|
male |
4 |
comorbid conditions |
0 |
0 |
|
1 |
3 |
|
>= 2 |
10 |
chest X-ray |
normal |
0 |
|
abnormal |
5 |
oxygen saturation |
>= 95% |
0 |
|
< 95% |
3 |
serum LDH |
<= ULN |
0 |
|
> ULN |
7 |
absolute neutrophil count |
< LLN |
-6 |
|
LLN to ULN |
0 |
|
> ULN |
10 |
platelet count |
>= LLN |
0 |
|
< LLN |
3 |
absolute lymphocyte count |
>= LLN |
0 |
|
< LLN |
-1 |
total score =
= SUM(points for all 9 parameters)
Interpretation:
• minimum score: -7
• maximum score: 76
• The higher the score the greater the risk of death.
Total Score |
Mortality Rate |
<= 0 |
< 1% |
1 to 10 |
2% |
11 to 20 |
5% |
21 to 30 |
13% |
31 to 40 |
27% |
41 to 45 |
43% |
46 to 50 |
54% |
51 to 55 |
66% |
56 to 60 |
76% |
61 to 70 |
87% |
> 70 |
> 91% |
Performance:
• The area under the ROC curve is 0.88 in the derivation cohort and 0.89 in the validation cohort.
Specialty: Infectious Diseases