COMPARISON BETWEEN ORGANISMAL STAINING AND TISSUE CULTURES FOR INFECTIONS

All patients from a single institution who had biopsies taken for both histology and tissue culture over a 5-year period were included in this study (N=179). The two tests agreed in 72.6% of cases, yielding a kappa correlation coefficient of 0.25. Specimens with positive histology only demonstrated a greater proportion of deep fungal infections (3/12) compared with specimens with positive tissue culture only, which demonstrated a greater proportion of gram-negative bacteria (20/37). Sensitivity of both tests was less than 50%.

 

This study demonstrates the high rate of discordance between histology and tissue culture in diagnosing cutaneous infections and the low sensitivity of each test. Unique strengths of each test include ability of histology to identify fungi and tissue culture to identify gram-negative bacteria, which may be helpful in guiding clinical practice.

 

Source: Margaret Hammond, MD, Practice Update [2/13/20] via Dr. Allen Jacobs

Courtesy of Barry Block, editor of PM News