Serum protein electrophoresis: an interesting diagnosis tool to distinguish viral from bacterial community-acquired pneumonia

Abstract

29-69 % of pneumonias are microbiologically documented because it can be considered as an invasive procedure with variable test sensitivity. However, it drastically impacts therapeutic strategy in particular the use of antibiotics. Serum protein electrophoresis (SPEP) is a routine and non-invasive test commonly used to identify serum protein disorders. As virus and bacteria may induce different globulins production, we hypothesize that SPEP can be used as an etiological diagnosis test. Retrospective study conducted from 1/1/13 until 5/1/15 among patient hospitalized for an acute community-acquired pneumonia based on fever, crackles and radiological abnormalities. α/β, α/γ, β/γ globulins and albumin/globulin (A/G) ratio were calculated from SPEP. Data were analyzed in 3 groups: documented viral (DVP) or bacterial pneumonia (DBP) and supposedly bacterial pneumonia (SBP). We used ANOVA statistic test with multiple comparisons using CI95 and ROC curve to compare them. 109 patients included divided into DBP (n = 16), DVP (n = 26) and SBP (n = 67). Mean age was 62 ± 18 year-old with a sex ratio M/F of 1.3. Underlying conditions (e.g. COPD, diabetes) were comparable between groups in multivariate analysis. Means of A/G ratio were 0.80 [0.76-0.84], 0.96 [0.91-1.01], 1.08 [0.99-1.16] respectively for DBP, SBP and DVP (p = 0.0002). A/G ratio cut-off value of 0.845 has a sensitivity of 87.5 % and a specificity of 73.1 %. A/G ratio seems to be an easy diagnostic tool to differentiate bacterial from viral pneumonia. A/G ratio cut-off value below 0.845 seems to be predictable of a bacterial origin and support the use of antibiotics.

The good and the bad: using C reactive protein to distinguish bacterial from non-bacterial infection among febrile patients in low-resource settings

“…A model using data from the study in patients with acute respiratory infection in Vietnam 28 showed that CRP testing at a cut-off of 20 mg/L (10 mg/L in those aged 1-5 years) can be cost-beneficial providing that adherence to test results is high (>70% for a unit cost of US$0.5 and >80% for a unit cost of US$1). 29 This assumed an economic cost of antimicrobial resistance of US$4.1, based on published modelling data from Thailand.…”

Significance of serum protein electrophoresis in the diagnosis of Tsukayama type IV periprosthetic joint infection

“…SPE is a routine, convenient clinical test and has been widely utilized for diagnosing liver diseases ( Papadopoulos et al., 1990 ), renal diseases ( Chew et al., 1999 ), multiple myeloma ( Dejoie et al., 2016 ), and connective tissue disorders ( Madda et al., 2019 ). And recent studies also corelated the alteration of SPE with infection ( Davido et al., 2016 ). Our previous research has also reported a good PJI diagnostic value of albumin to globulin ratio and a fair diagnostic value of overall serum globulin independently ( Shang et al., 2022 ).…”

Reduce, Reuse, Recycle: Top 10 Choosing Wisely Canada’s Recommendations for Conserving Laboratory Resources

“…16 Many acute inflammatory processes, including bacterial and viral infections, can create focussed reactive changes in immunoglobulins which may be initially mistaken for a monoclonal protein, or prevent the confident determination of an absence of a plasma cell dyscrasia. [16][17][18] Certain electrophoresis methods are also subject to interferences from imaging contrast dyes and antibiotics. 19 Ordering these tests in the hospital frequently leads to follow-up testing after the reactive process and acute therapy resolve.…”