suPAR as a biomarker for infectious diseases

The suPAR level is elevated in patients with infectious diseases compared with healthy individuals, and an elevated level is associated with:

  • Advanced disease
  • Poor prognosis

This applies to various infectious diseases, among others:

  • HIV1-5,25
  • Sepsis6-11
  • Hepatitis B12
  • Hepatitis C13-14
  • Tuberculosis15-17
  • Malaria18-19
  • Meningitis21-22
  • Pneumonia23-24

In general, the suPAR level is slightly elevated in patients with infectious diseases, and in all infectious diseases studied, an elevated suPAR level is associated with a poorer prognosis. In infectious diseases, the diagnostic value of suPAR is weak, but instead it has a prognostic value.

“It has become clear that suPAR is a very strong prognostic marker, exceeding the prognostic value of all other routinely measured biomarkers in our hospital.”

Prof. Ove Andersen,
MD, PhD, DmSc, Copenhagen University Hospital Hvidovre, Denmark
suPAR News Vol. 3, June 2020

HIV

In patients with HIV infection, it was demonstrated that the suPAR level is slightly elevated and increases with the disease stage (WHO criteria). The first study of suPAR in HIV showed that suPAR was at least as strong a prognostic marker of the natural progression of HIV as CD4 and viral load1. Antiretroviral therapy (ART) causes a decrease in suPAR of about 17%2. However, after 5 years of treatment, the patients’ suPAR level is still higher than in healthy controls2. Side effects of treatment are associated with higher suPAR levels3. In addition to the correlation with virological and immunological effects of the infection, the suPAR level correlates with age, metabolic syndrome, smoking, and low muscle mass4. In HIV patients with ARTinduced viral suppression, suPAR is a superior and independent predictor of non-AIDS events comorbidities (e.g. cardiovascular and renal diseases).

Sepsis

In patients with sepsis5-7, it has been found that the suPAR level is of some diagnostic value, as it increases with seriousness of sepsis and is frequently above 10 ng/mL in patients with impaired organ function8,9. However, most studies show that CRP and procalcitonin (PCT) are better diagnostic markers of bacterial sepsis, whereas suPAR is the best prognostic marker6,10. In a later cohort it was shown and validated that suPAR in combination with the APACHE score can improve the risk stratification of patients with sepsis11.