C-reactive protein and procalcitonin use in adults in low- and middle-income countries: a narrative review

Abstract

Objectives C-reactive protein (CRP) and procalcitonin (PCT) are widely used biomarkers in high-income countries. However, evidence for their use in low- and middle-income countries (LMICs) is scant. Because many factors, including rates of endemic disease, comorbidities and genetics, may influence biomarkers’ behaviour, we aimed to review available evidence generated in LMICs. Methods We searched the PubMed database for relevant studies within the last 20 years that originated in regions of interest (Africa, Latin America, Middle East, South Asia or South East Asia), and full-text articles involving diagnosis, prognostication and evaluation of therapeutic response with CRP and/or PCT in adults (n = 88) were reviewed and categorized in 12 predefined focus areas. Results Overall, results were highly heterogeneous, at times conflicting, and often lacking clinically useful cut-off values. However, most studies demonstrated higher levels of CRP/PCT in patients with bacterial versus other infections. HIV and TB patients had consistently higher levels of CRP/PCT versus controls. In addition, higher CRP/PCT levels at baseline and follow-up in HIV, TB, sepsis and respiratory tract infections were associated with poorer prognosis. Conclusions Evidence generated from LMIC cohorts suggests that CRP and PCT may have potential to become effective clinical guiding tools particularly in respiratory tract infections, sepsis and HIV/TB. However, more studies are needed to define potential scenarios for use and cost-effectiveness. Consensus across stakeholders regarding target conditions, laboratory standards and cut-off values would support the quality and applicability of future evidence.

Correlation of procalcitonin and c-reactive protein levels with pathogen distribution and infection localization in urinary tract infections

“…PCT and CRP have garnered attention as potential indicators of infection severity and response to treatment 5 . PCT and CRP are inflammatory biomarkers that have been shown to support diagnosis and monitoring of (bacterial) respiratory tract infections and sepsis 6 , 7 . While limited studies suggest their usefulness in supporting the sites of UTI diagnosis, their performance in different UTI scenarios remains a subject of investigation.…”

Peripheral inflammatory response in people after acute ischaemic stroke and isolated spontaneous cervical artery dissection

“…It is crucial to acknowledge that CRP, as an acute-phase protein, is a nonspecific indicator of inflammation. Elevated CRP levels can result from infections 87 , tissue damage associated with atherosclerosis or ischaemic stroke 88 , chronic diseases 89 , or autoimmune disorders 90 , 91 . Therefore, there is a possibility of misclassifying AIS patient into the > 5 mg/l group if elevated CRP levels did not originate from the acute stroke event.…”

Management of Sepsis and Septic Shock: What Have We Learned in the Last Two Decades?

“…However, additional studies are needed to define potential beneficial scenarios and cost-effectiveness before advocating for broad usage. [ 151 ]. Monocyte distribution width is a new biomarker for infection and has shown to be at least equivalent to procalcitonin and CRP, if not superior [ 152 , 153 ].…”