Five decades in, albumin-adjusted calcium is still the default — and according to this editorial perspective, it shouldn't be. Chiang and Choy argue that the field has accumulated more than enough evidence to retire "corrected calcium" as a universal screening tool, yet labs continue to auto-report it as though the math holds up across all patients. The authors argue it does not. In older patients, the critically ill, and those with renal impairment, pH shifts and protein disturbances can quietly invalidate the albumin-adjustment formula — meaning clinical decisions about hypo- and hypercalcaemia may be based on values that do not accurately reflect physiologically active calcium.

Here's what's actually overdue: the authors point out that this wasn't even a new critique in 2025. The concept of "corrected calcium" was challenged in the British Medical Journal back in 1975. The evidence has been building for half a century, and inertia — not science — is what's keeping adjusted calcium on lab reports.

The friction is practical. Ionised calcium requires careful pre-analytical handling, and not every lab or clinical setting has seamlessly integrated it into routine workflows. Changing a reflexively reported value means retraining ordering habits across entire institutions.

The takeaway: The authors argue that labs still auto-reporting albumin-adjusted calcium as a universal fallback deserve a second look — ionised calcium is the more defensible standard, particularly in high-acuity settings. At minimum, clinicians should know when not to trust the adjusted number.

The authors stated that there are no conflicts of interest to disclose.

Source: Pathology