In patients presenting with skin and soft tissue infections (SSTI), the use of ultrasound may lead to a more accurate distinction between cellulitis and abscess compared with clinical assessment alone.
This systematic review aims to determine the diagnostic accuracy of ultrasound for detecting skin abscesses. In addition, it aims to assess the impact of using ultrasound on management decisions in patients with SSTI.
We searched relevant electronic databases for primary studies including MEDLINE, EMBASE, and CINAHL. We searched conference proceedings, checked references of retrieved articles, and contacted field experts. Two reviewers assessed the quality of each full-text publication using a modified QUADAS-2 tool.
Five studies (n=710) fulfilled our inclusion criteria. Four studies compared the diagnostic accuracy of ultrasound with clinical examination alone (n=584). Most studies reported an improvement in diagnostic accuracy. The sensitivity of ultrasound ranged from 89 to 98% and the specificity ranged from 64 to 88%. However, the sensitivity of clinical assessment ranged from 75 to 90% and the specificity ranged from 55 to 83%; most of these results did not reach statistical significance. Sensitivity was further improved in cases of indeterminate clinical assessment. Two studies (n=176) examined the impact of ultrasound on management decisions. Use of ultrasound has led to significant and appropriate changes in management decisions in 16 to 39% of patients.
The use of ultrasound could potentially improve diagnostic accuracy and lead to improved management decisions in patients with SSTI, especially in cases of indeterminate clinical assessment. Most of our findings did not achieve statistical significance. Further research is required to confirm these findings.