Reply to Letter from Dr. Ushakov on “Thyroid nodules that disappear—a case report on pseudonodules in thyroiditis”

Thanks for the letter from Dr. Ushakov about our case report (1) on pseudonodules in thyroiditis. We appreciate the enthusiasm Dr. Ushakov showed in his letter. However, we are concerned that he misunderstood us in the following ways.

First, the prefix “pseudo-”, derived from Greek, means spurious in the English language (2). Thus, the term “pseudonodule” obviously denotes a false nodule that should not be treated as such in the first place. On this note, we fully agree with Dr. Ushakov that treating the regional, hypoechoic changes in the thyroid gland of a patient with De Quervain’s (subacute granulomatous) thyroiditis as nodules is incorrect. This is the very motivation for us to report this case. We are in fact, sharing a similar “perception of reality” with Dr. Ushakov.

However, we wish to inform Dr. Ushakov that our patient’s ultrasonographic report clearly stated that she had “multiple nodules in both lobes of the thyroid, some are ill-defined” after her initial presentation of a painful goitre. Before publication of our case report, a head and neck radiologist reviewed the images and found that the left thyroid lobe was heterogeneous without distinct nodules, but 2 nodules in the right lobe were distinct. We described these in our case report. This is the reality we face, that focal changes in the thyroid parenchyma can be interpreted as nodules on ultrasonography. To correct this “distorted perception of reality” [Ushakov (3)], the description of “segments” of the thyroid gland as opposed to nodules by Dr. Ushakov intrigued us. We quote, “such segments were already present before the disease, since the parenchyma of a healthy thyroid consists of such segments of different levels” (3). We must mention that this is not a common term used to describe the anatomy of the thyroid gland in comparison to the liver, for example. It may be better to stick with the term “lobules” that Dr. Ushakov used synonymously with segments in his previous publications (4). Histology of the thyroid gland supports the claim that it consists of distinct lobules separated by septa invaginating from the gland capsule, with each lobule containing its own arteriole (5). These lobules coalesce to form the lobes and the isthmus of the gland as we normally know. We suggest that Dr. Ushakov refer to “segments” as “lobules” of the thyroid gland for the sake of a wider acceptance of his view.

Second, we are surprized by Dr. Ushakov’s assertion that the thyroiditis in our case is “unilateral” (3), and that there is an “absence of signs of ST” (3), i.e., subacute thyroiditis. A careful reader would notice that our patient’s thyroid swelling and tenderness was initially noted on the left lobe but the nodular changes were only present in the right lobe when she underwent ultrasonography later on. Her painful thyroid swelling, the acute history, and the transient hyperthyroidism all supported the diagnosis of subacute thyroiditis. That the pseudonodules are observed unilaterally is not a surprise in subacute thyroiditis, as Dr. Ushakov himself stated (3,6), and may not preclude the involvement of the rest of the gland in the inflammatory process. In fact, the size of the left lobe of the thyroid gland in our patient decreased from 4.0 cm × 1.0 cm × 1.6 cm to 4.0 cm × 1.2 cm × 0.9 cm during follow-up, and the size of the right lobe of the gland decreased from 4.8 cm × 1.6 cm ×1.5 cm to 4.2 cm × 1.1 cm ×1.2 cm as the pseudonodules resolved. Because only representative images of the sonography are captured during the archiving process, it is not possible to always match the site of image capture in follow-up scans, but the images we provided in Fig. 3 do represent the visualized thyroid parenchyma. Dr. Ushakov’s assertion that subacute thyroiditis can be explained by a “neural principle” instead of a viral-mediated process is based on a paucity of robust data (4). More proof is required to substantiate this claim.

Third, Dr. Ushakov appears to be concerned about the title of our case report and some lines in the manuscript that describe the resolution of “thyroid nodules”. In fact, in both our title and the manuscript, it is clear that we mean the resolution of pseudonodules as the inflammatory process in the thyroid gland abates. Histopathology of the inflamed thyroid gland can provide direct evidence about nodular formation in subacute thyroiditis. As surgery is rarely performed on this condition, we wish to intrigue Dr. Ushakov on this case series that observed the formation of solid nodules from fibrosis associated with inflammation in De Quervain’s thyroiditis (7). Once again, we thank Dr. Ushakov for his impassioned discourse on our case report.

Acknowledgments

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the Editorial Office, Annals of Thyroid. The article did not undergo external peer review.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://aot.amegroups.com/article/view/10.21037/aot-24-58/coif). H.L. serves as an unpaid editorial board member of Annals of Thyroid from September 2023 to August 2025. C.Y.Z.K. is a Medical Officer employed under the Ministry of Health Holdings, Singapore, the holding company of Singapore’s public healthcare institutions. It has no conflicts of interest with the publication of this article. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Kok CYZ, Liew H, Khoo HW, et al. Thyroid nodules that disappear—a case report on pseudonodules in thyroiditis. Ann Thyroid 2024;9:3. [Crossref]
2. Google Dictionary (Oxford Languages). Accessed on 3 Oct 2024.
3. Ushakov AV. Thyroid nodules, pseudonodules and large segments: from empirics to reality. Ann Thyroid 2024;9:4. [Crossref]
4. Ushakov AV. Principles and features of ultrasound hypoechogenicity in diffuse thyroid pathology. Quant Imaging Med Surg 2024;14:2655-70. [Crossref] [PubMed]
5. Gartner LP. Textbook of Histology. 5th Edition. Elsevier Health Sciences; 2020.
6. Sencar ME, Calapkulu M, Sakiz D, et al. The contribution of ultrasonographic findings to the prognosis of subacute thyroiditis. Arch Endocrinol Metab 2020;64:306-11. [Crossref] [PubMed]
7. Ranganath R, Shaha MA, Xu B, et al. de Quervain's thyroiditis: A review of experience with surgery. Am J Otolaryngol 2016;37:534-7. [Crossref] [PubMed]