Letters about Published Papers

Re: Gautam et al. Effectiveness of leucocyte esterase as a diagnostic test for acute septic arthritis. J Orthopaedic Surgery, published 2017, 25(1). DOI: 10.1177/2309499016685019

Leucocyte esterase as a diagnostic test for acute septic arthritis

To the Editor,

The recent publication on “Leucocyte esterase as a diagnostic test for acute septic arthritis” is very interesting. ¹ Gautam et al. noted that “the leucocyte esterase strip test yielded a high specificity, PPV, NPV, high sensitivity and high diagnostic accuracy. ¹ ” There are some concerns on this work. First, there are few subjects in this study. To evaluate a diagnostic test, a proper number of subjects should be used. In addition, there is no evaluation on the interferences of the diagnostic test. In fact, in the report, Gautam et al. used leucocyte esterase strip (Multistix) as a diagnostic test. There might be many possible errors in strip testing and reading. Generally, the strip is designed for urine test, not for other body fluids. Despite the strip is correctly used for urine test, random error is still very common. ² Finally, the cost effectiveness of the test should also be assessed. As noted by Adams, “a multiple reagent strip is neither cost effective nor clinically useful.” ³

Viroj Wiwanitkit Hainan Medical University, Haikou, China