Is there a role for phenotyping patients with CSU outside of a research setting by ordering IgG-anti-TPO, IgG anti-FceRI, total IgE, total IgA, etc.?

I do think it can be helpful in patients who have difficult-to-control disease. Many of these (e.g. IgG-anti-TPO, total IgE, anti-thyroglobulin antibody) have been shown to help predict responsiveness to omalizumab treatment or have been associated with disease activity (Højgaard Pedersen et al., PM...

Yes—but I would call it pragmatic endotyping rather than definitive phenotyping. There is useful information here, but we are not yet at the point where a laboratory panel reliably assigns a patient to a treatment pathway. (Although here again, our allergy colleagues may disagree)

This is one of the ...

There has been a paradigm shift in laboratory testing for patients with chronic spontaneous urticaria. Laboratory studies to identify an underlying etiology in patients with an otherwise unremarkable history and physical exam are not recommended, as routine testing has not been shown to be cost-bene...