Serum antiphospholipid antibody levels as biomarkers for diagnosis of pulmonary tuberculosis patients

Int J Tuberc Lung Dis. 2018 Sep 1;22(9):1063-1070. doi: 10.5588/ijtld.17.0874.

Abstract

Setting: Salvador, Bahia, Brazil.

Objective: To evaluate the immunoglobulin (Ig)M and total IgG antibody response to cardiolipin (CL), phosphatidylcholine (PTC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and sulfatide (SL-I) as biosignatures that can be used to diagnose pulmonary tuberculosis (TB) and its applicability for monitoring the efficacy of anti-tuberculosis treatment.

Design: Serum samples from 37 adult pulmonary TB patients and 48 controls (16 healthy household contacts, 19 household contacts with latent tuberculous infection [LTBI] and 13 non-TB patients with lung disease) were screened using enzyme-linked immunosorbent assays (ELISAs) for IgM and total IgG against phospholipids.

Results: Levels of IgM response to CL, PE and PI, and IgG response to CL, PE, PI and PTC were significantly higher in TB patients than in control groups. Anti-CL IgG had the best performance characteristics, with a sensitivity and specificity of respectively 86.5% and 87.2%. This IgG anti-CL ELISA test detected 86.5% (32/37) of the TB patients, whereas the number detected using sputum smear was only 65.9% (24/37). After anti-tuberculosis treatment, the median value for all anti-phospholipid antibodies decreased significantly compared with baseline values (P < 0.05).

Conclusion: Our results suggest that the total IgG anti-CL level could be useful to complement conventional bacteriological tests for the rapid diagnosis of adult pulmonary TB.

MeSH terms

  • Adult
  • Antibodies, Antiphospholipid / blood*
  • Biomarkers / blood
  • Brazil
  • Cross-Sectional Studies
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin M / blood
  • Mycobacterium tuberculosis / isolation & purification*
  • Sensitivity and Specificity
  • Sputum / microbiology*
  • Tuberculosis, Pulmonary / blood
  • Tuberculosis, Pulmonary / diagnosis*

Substances

  • Antibodies, Antiphospholipid
  • Biomarkers
  • Immunoglobulin G
  • Immunoglobulin M