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. 2010 Feb 18;24(1):203–228. doi: 10.1016/j.idc.2009.10.001

Table 5.

Winthrop-University Hospital Infectious Disease Division's swine influenza (H1N1) pneumonia diagnostic weighted point system in adults with negative rapid influenza diagnostic tests (RIDTs)

Clinical Features Point Scores Swine Influenza (H1N1) Laboratory Diagnosed Swine Influenza (H1N1) Clinically Diagnosed ILIs not Swine Influenza (H1N1) CMV CAP Q Fever CAP Legionella CAP
Adults with an ILI with dry cough, fever >39°C/102°F and a CXR with no focal/segmental lobar infiltratesa
  • •

    Severe myalgias

 +5 +5 +5 0 0 0 0
  • •

    Relative lymphopenia (otherwise unexplainedb)

 +5 +5 +5 0 +5 +5 +5
  • •

    Elevated CPK (otherwise unexplained)

 +3 +3 +3 0 0 0 +5
  • •

    Elevated serum transaminases (otherwise unexplained)

 +2 +2 +2 0 +2 +2 +2
  • •

    Thrombocytopenia (otherwise unexplained)

 +5 +5 +5 0 +5 +2 0
Argues against the diagnosis of (H1N1):
  • •

    Relative bradycardia (otherwise unexplained)

 −5 0 0 0 0 0 −5
  • •

    Leukopenia (otherwise unexplained)

 −2 0 0 0 0 0 0
  • •

    Atypical lymphocytes

 −1 0 0 0 0 0 0
  • •

    Highly elevated serum ferritin levels (>2 × n)

 −5 0 0 0 0 0 −5
  • •

    Hypophosphatemia

 −3 0 0 0 0 0 −3
Swine influenza Diagnostic Point Score totals: Total score: 20 20 0 12 9 −1
Probable swine influenza (H1N1) pneumonia = >15
Possible swine influenza (H1N1) pneumonia = 10–15
Unlikely swine influenza (H1N1) pneumonia = <10

Abbreviation: ILIs, Influenzalike illnesses.

Data from Cunha BA, Syed U, Stroll S, et al. Winthrop-University Hospital infectious disease division's swine influenza (H1N1) pneumonia diagnostic weighted point score system for adults with Influenza Like Illnesses (ILIs) and negative Rapid Influenza Diagnostic Tests (RIDTs). Heart Lung 2009;38:534–8.

a

Q fever and legionnaire's disease CAPs usually have focal segmental/labor infiltrates.

b

Other causes of relative lymphopenia: Infectious causes: CMV, HHV-6, HHV-8, HIV, military TB, Legionella, typhoid fever, Q fever, brucellosis, SARS, malaria, babesiosis, influenza, avian influenza, RMSF, histoplasmosis, dengue fever, Chickungunya fever, ehrlichiosis, parvovirus B19, HPS, WNE, viral hepatitis (early); Noninfectious causes: cytotoxic drugs, steroids, sarcoidosis, SLE, lymphoma, RA, radiation therapy, Wiskott-Aldrich syndrome, Whipple disease, severe combine immunodeficiency disease (SCID), common variable immune deficiency (CVID), Di George syndrome, Nezelof syndrome, intestinal lymphangiectasia, constrictive pericarditis, tricuspid regurgitation, Kawasaki disease, idiopathic CD4 cytopenia, Wegener granulomatosis, acute/chronic renal failure, hemodialysis; myasthenia gravis, celiac disease, alcoholic cirrhosis, coronary bypass, CHF, acute pancreatitis, carcinomas (terminal).