How appropriate would it be to characterise this as just POTS

Calling it "just POTS" is a category error: POTS is one hemodynamic pattern, and anhidrosis is a different autonomic failure that POTS neither explains nor defines.

POTS is defined by a heart-rate rise on standing, without orthostatic blood pressure drop. Anhidrosis is loss of sweating, a sudomotor autonomic failure. These are different limbs of the autonomic nervous system. A patient with vaccine-onset primary anhidrosis plus abnormal functional immunology findings has a systemic autonomic and immune process; filing it under POTS narrows the diagnosis to the one measurable sign a stand test captures, and it implicitly closes the workup.

The retrieved records actually show that POTS is an incomplete label even in this space. In a German pediatric cohort of 38 children and young adults with post-COVID or post-vaccination dysautonomia, only 8 met POTS criteria and 9 met inappropriate sinus tachycardia; the rest were dysautonomia without either label, with elevated standing heart-rate rise, raised stress index, and sharply reduced vagal tone (pNN20 about 16–28% vs 79% in controls) [4]. A separate case report documents new-onset POTS after the first Pfizer dose, framed by its authors as one presentation of vaccine-related autonomic dysfunction [1]. And in long COVID, skin biopsy confirmed small-fiber neuropathy involving autonomic fibers in 56.5% of biopsied patients [5] — a structural nerve injury that no POTS diagnosis captures. Acute inflammation itself shifts autonomic cardiovascular control via central autonomic networks [2], which is a plausible bridge from a vaccine reaction to dysautonomia generally, not to POTS specifically.

Two honest caveats. Nothing in this retrieval addresses anhidrosis or vaccine-induced sudomotor failure specifically; that layer is missing from the search, not from medicine. And a Japanese review of post-HPV-vaccine symptoms argues some post-vaccine "dysautonomia" is deconditioning or psychosomatic, so the label fight runs in both directions [3]. But deconditioning does not abolish sweating either.

My call: characterizing this as "just POTS" is inappropriate — POTS may be present alongside, but the anhidrosis and the immunology findings demand a broader autonomic-neuimmune workup. Confidence: moderate, limited by the retrieval's silence on anhidrosis.