Table 10.
Winthrop-University Hospital Infectious Disease Division's diagnostic weighted point score system for diagnosing legionnaires' disease in adults (modified)
| Presentation | Qualifying Conditionsb | Point Score |
|---|---|---|
| Clinical features | ||
| • Temperature >102°Fa | With relative bradycardiaa | +5 |
| • Headachea | Acute onset | +2 |
| • Mental confusion/lethargya | Not drug-induced or toxic/metabolic | +4 |
| • Ear pain | Acute onset | −3 |
| • Nonexudative pharyngitis | Acute onset | −3 |
| • Hoarseness | Acute not chronic | −3 |
| • Sputum (purulent) | Excluding AECB | −3 |
| • Hemoptysisa | Mild/moderate | −3 |
| • Chest pain | Pleuritic | −3 |
| • Loose stools/watery diarrheaa | Not drug induced | +3 |
| • Abdominal paina | With/without diarrhea | +5 |
| • Renal failurea | Acute (not chronic) | +3 |
| • Shock/hypotensiona | Excluding cardiac/pulmonary causes | +1 |
| • Splenomegalya | Excluding non-CAP causes | −5 |
| • Lack of response to β-lactam antibiotics | after 72 h | +5 |
| Laboratory tests | ||
| • Chest radiograph | Rapidly progressive asymmetric infiltratesa (excluding influenza, CMV, HPS, SARS) | +3 |
| • Severe hypoxemia (↑ A-a gradient >35)a | Acute onset (excluding influenza HPS, SARS) | −2 |
| • Hyponatremiaa | Acute onset | +1 |
| • Hypophoshatemiaa | Acute onset | +5 |
| • ↑ AST/ALT (early/mild/transient)a | Acute onset | +2 |
| • ↑ Total bilirubin | Acute onset | +1 |
| • ↑ LDH (>400)a | Acute onset | −5 |
| • ↑ CPKa | Acute onset | +3 |
| • ↑ CRP >35a | Acute onset | +5 |
| • ↑Cold agglutinin titers (≥1:64)a | Acute onset | −5 |
| • Severe relative lymphopenia (<10%)a | Acute onset | +5 |
| • ↑ Ferritin (>2 × n)a | Sustained elevations | +5 |
| • Microscopic hematuriaa | Excluding trauma, BPH, Foley catheter, bladder/renal neoplasms | +2 |
| Likelihood of Legionella | ||
| Total point score | >15 Legionnaires' disease very likely | |
| 5–15 Legionnaires' disease likely | ||
| <5 Legionnaires' disease unlikely | ||
Abbreviations: AECB, acute exacerbation of chronic bronchitis; BPH, benign prostatic hyperplasia; LDH, lactate dehydrogenase.
Adapted from Cunha BA, editor. Pneumonia essentials. 3rd edition. Sudbury (MA): Jones & Bartlett; 2010; with permission.
a
Otherwise unexplained.
b
In adults, otherwise unexplained, acute and associated with the pneumonia.