CRP and bacterial infectious disease: Procalcitonin and lactate are endorsed by international sepsis guidelines as pivotal diagnostic and prognostic biomarkers.[3,33] Procalcitonin, a calcitonin precursor undetectable in healthy individuals, rises rapidly during bacterial infections, with levels proportional to disease severity.[34,35] Its diagnostic performance surpasses conventional markers like C-reactive protein,[36,37] and serial measurements guide antibiotic stewardship.[38,39] Blood lactate level is an important indicator reflecting tissue perfusion and cellular hypoxia.