S100P and pachyonychia congenita: Furthermore, S100 calcium-binding protein P (S100P) may be a viable biomarker in the diagnosis of PC with a pooled sensitivity of 0.87 (95 % CI: 0.83–0.90), pooled specificity of 0.88 (95 % CI: 0.82–0.93) and AUC of 0.9272 in the Hu meta-analysis [43].