Background Cutaneous viral warts are benign epidermal proliferations caused by human
papillomaviruses (HPVs). Despite treatment, a significant proportion of warts fail to resolve,
becoming recalcitrant. Vitamin A (retinol) may disrupt the interplay of HPV replication and
epithelial cell differentiation, allowing normal tissue to replace warts. Circulating retinolbinding
protein (RBP) concentrations highly correlate with retinol levels.
Aim We aimed at evaluation of serum RBP level in patients with recalcitrant cutaneous
warts in order to assess its correlation with disease pathogenesis.
Methods Serum RBP level was measured by an ELISA technique in 50 patients with
recalcitrant cutaneous warts and 30 apparently healthy controls.
Results Serum RBP level was significantly lower in patients with recalcitrant warts than the
control group (P < 0.001). However, it did not differ regarding different clinical parameters in
studied patients (P > 0.05 each). RBP is a reliable biomarker for significant early detection
and discrimination between patients and healthy controls (P < 0.001) at a cutoff value
≤1034.6 lg/ml, with sensitivity and specificity (100% each).
Conclusion Our results revealed that low serum RBP as a relatively cheap biomarker with
high specificity and sensitivity is a reliable indicator of vitamin A (retinol) deficiency that
may play a role in the pathogenesis of recalcitrant cutaneous warts among our studied
patients.