u/Traditional_Buy7910

I caught COVID in October 2020. Burning pain in my feet started almost immediately afterwards, and I was diagnosed within the next couple of years with post-COVID small fiber neuropathy.

For five years, the SFN was the main issue. Since January, I have developed persistent dry eyes and intermittent dry mouth. I have now had ocular, salivary gland and autoimmune testing, and the overall picture is strongly suggestive of Sjögren’s disease. Further confirmation is still being pursued, but a rheumatologist with specific expertise in Sjögren’s considers the diagnosis close to certain.

His interpretation is that Sjögren’s may have been the underlying disease from the start: COVID may have triggered or unmasked it, SFN may have been the first manifestation, and the sicca symptoms only became obvious years later.

I am trying to understand whether others have had a similar trajectory.

Has anyone here had SFN after COVID and later been diagnosed with Sjögren’s? If so, what were the practical implications of this diagnosis (for treatment, monitoring, prognosis, or simply understanding what was happening)?

Sources:
https://pmc.ncbi.nlm.nih.gov/articles/PMC11087026/
https://pure.johnshopkins.edu/en/publications/biopsy-proven-small-fiber-neuropathy-in-primary-sj%C3%B6grens-syndrome/
https://insight.jci.org/articles/view/166540

Since 2020, I (50 M) have been suffering from post-COVID, immune-related SFN, and I am one year into a high-dose (2 g/kg every three weeks) IVIg treatment (following the McAlpine et al 2024 protocol: https://pubmed.ncbi.nlm.nih.gov/38630952/).

Since January, I have been suffering from (perceived) severe eye dryness, nearly constantly, and mouth dryness, sporadically.

When I discussed these new symptoms with my neurologists, he raised the possibility that it could be Sjögren's disease and recommended that I should undergo tests to further assess it, and then meet with a Sjögren's specialist if the tests were abnormal.

The tests indeed seem abnormal, although the blood tests may be biased by the IVIg infusions. Based on your experience, do you think I could be suffering from Sjögren's disease? Is there any possibility that the symptoms could be caused by the IVIg treatment itself? They started more or less at the same time as when I started responding to the treatment.

Eyes
Schirmer: 7 (R) / 10 (L)
T-BUT: 4 (R) / 3 (L)
Posterior blepharitis

Blood (potentially biased by IVIg)
CRP: 3.1 (normal: < 5)
C3 Complement: 125 (normal: 90-170)
C4 Complement: 5 (normal: 12-36)
ANA: Positive
Titers: 1/160 (speckled)
DFS70: Positive
SSA: Weakly positive
SSB: Negative
Anti-TRIM21: Weakly positive

Salivary gland scintigraphy
“The salivary gland scintigraphy is suggestive of parenchymal involvement of the parotid and submandibular glands, compatible with Sjögren’s syndrome.”

Thank you.