The value of procalcitonin measurement in localized skin and skin structure infection, diabetic foot infections, septic arthritis and osteomyelitis

Abstract

Serum procalcitonin (PCT) is an established diagnostic marker for severe or systemic bacterial infections such as pneumonia, sepsis and septic shock. Data regarding the role of PCT in localized infections without systemic inflammatory response syndrome are scarce. The aim of this review is to assess the value of PCT measurements in localized infections such as skin and skin structure infections, diabetic foot infections, septic arthritis (SA) and osteomyelitis. It appears that serum PCT is unlikely to change the clinical practice in skin and skin structure infection. However, serum PCT could have a role in diagnosis and monitoring of diabetic foot infections in hospitalized settings. There are conflicting reports regarding the ability of serum PCT to distinguish SA from non-SA; synovial PCT may be more appropriate in these settings, including in implant-related infections. Better designed studies are needed to evaluate the usefulness of PCT with or without other biomarkers in localized infections.

Keywords::

• arthritis
• diabetic foot infections
• localised infections
• procalcitonin
• septic

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Treatment decisions and duration of antibiotic therapy in localized skin infections should remain to depend mainly on clinical findings.

• Based on the limited and small studies serum procalcitonin (PCT) could potentially have a role in diabetic foot infections.

• Among diabetic foot infections, serum PCT does not differentiate osteomyelitis and severe infections from less severe and soft tissue infection only.

• Currently, there are insufficient data to support the routine use of serum PCT in the differentiation of septic arthritis (SA) from non-SA especially by using cut-off values of ≥0.5 ng/ml.

• Lowering the serum PCT cut-off level, for example, to ≥0.25 or 0.3 ng/ml, may provide better sensitivity with very little effect on specificity in differentiating SA from non-SA.

• Synovial PCT may be more beneficial in the diagnosis of SA, particularly in implant-related infections.

• Clinicians and diagnosticians need to be aware of the limitations of specific PCT assays.

• Larger studies are needed, with better designs using newer generation and more sensitive quantitative kits, in both emergency and outpatient settings to assess the reliability of PCT in supporting physicians when faces with diagnostic dilemmas.