Top Endocrine Publications of 2013: The Canine Thyroid Gland

In my fifth compilation of the canine and feline endocrine publications of 2013, I’m moving on to disorders of the canine thyroid gland. Listed below are 22 research papers written in 2013 that deal with a variety of thyroid gland topics and issues of clinical importance.

These range from a review of the neurologic manifestations of canine hypothyroidism (1) to a review of laryngeal paralysis (and related hypothyroidism) (8) to a dog with hypothyroid-related polyneuropathy (20); and from a case study of two dogs with thyroid carcinoma and hyperthyroidism that presented primarily for polyuria, polydipsia (2) to a case report of a dog suffering from thyroid carcino-sarcoma (6).

Other publications which deal with canine thyroid carcinoma include a CT study of eight dogs with sublingual ectopic thyroid tumors (13), a comparison between clinical, ultrasound, CT, MRI, and pathology findings in dogs presented for thyroid carcinoma (18), and use of conventional and cell block cytology for detection of thyroid carcinoma micrometastases to bone marrow (19). Reports of exogenous hyperthyroidism in dogs included two dogs with food-induced thyrotoxicosis (22) and one dog that developed hyperthyroidism secondary to ingestion of feces of another dog being treated with levothyroxine (16).

Three basic research studies involved dogs and the thyroid gland: one was designed to identify the critical amino acids along the transport channel cavity involved in thyroid hormone transport across the blood-brain barrier into neurons (3), whereas the goal of the second study was to develop a systems pharmacology model to describe the impact of thyroperoxidase inhibition on thyroid hormone homeostasis and drug-induced changes in thyroid hormone concentrations (4). The third study looked at thyroid peroxidase enzyme expression in the dog and determined that the structure of the canine gene has diverged with evolution and differs from both human and mouse (5).

Other papers report on various studies concerning diagnostic testing for hypothyroidism in dogs (12,15) to the issue of nonthyroidal illness (leishmaniosis) affecting thyroid function in dogs (14); from a study of the effect of the type of diet fed on thyroid hormone absorption in dogs (7) to the bioavailability of two preparations of L-T4 in dogs (17).

Finally, in this review, I have also included two papers that deal with species other than dogs. The first is a study of thyrotropin (TSH) stimulation testing in ferrets (9), and the other is a comparison of serum thyroid hormone concentrations in horses and donkeys, which were found to differ significantly (11).

References:

1. Bertalan A, Kent MS, Glass E. Neurologic manifestations of hypothyroidism in dogs. Compend Contin Educ Vet 2013;35:E2. 
2. Bosje T, den Hertog E, Dijksta M. Does the T4 measurement belong in the standard blood analysis in polyuria/polydipsia? Tijdschr Diergeneeskd 2013;138:230-231. 
3. Braun D, Lelios I, Krause G, et al. Histidines in potential substrate recognition sites affect thyroid hormone transport by monocarboxylate transporter 8 (MCT8). Endocrinology 2013;154:2553-2561. 
4. Ekerot P, Ferguson D, Glamsta EL, et al. Systems pharmacology modeling of drug-induced modulation of thyroid hormones in dogs and translation to human. Pharm Res 2013;30:1513-1524. 
5. Fyfe JC, Lynch M, Olsen J, et al. A thyroid peroxidase (TPO) mutation in dogs reveals a canid-specific gene structure. Mammalian genome 2013;24:127-133. 
6. Giuliano A, Grant J, Benoit J. Thyroid carcino-sarcoma in a dog. J S Afr Vet Assoc 2013;84:E1-5. 
7. Iemura R, Toyota M, Micallef MJ. Effects of type of diet on pharmacokinetics of levothyroxine sodium oral solution. Res Vet Sci 2013;94:695-697. 
8. Kitshoff AM, Van Goethem B, Stegen L, et al. Laryngeal paralysis in dogs: an update on recent knowledge. J S Afr Vet Assoc 2013;84:E1-9.
9. Mayer J, Wagner R, Mitchell MA, et al. Use of recombinant human thyroid-stimulating hormone for thyrotropin stimulation testing in euthyroid ferrets. J Am Vet Med Assoc 2013;243:1432-1435. 
10. McGonigle KM, Randolph JF, Center SA, et al. Mineralocorticoid before glucocorticoid deficiency in a dog with primary hypoadrenocorticism and hypothyroidism. J Am Anim Hosp Assoc 2013;49:54-57. 
11. Mendoza FJ, Perez-Ecija RA, Toribio RE, et al. Thyroid hormone concentrations differ between donkeys and horses. Equine Vet J 2013;45:214-218. 
12. Rasmussen SH, Andersen HH, Kjelgaard-Hansen M. Combined assessment of serum free and total T4 in a general clinical setting seemingly has limited potential in improving diagnostic accuracy of thyroid dysfunction in dogs and cats (Letter). Vet Clin Pathol 2014;43:1-3. 
13. Rossi F, Caleri E, Bacci B, et al. Computed tomographic features of basihyoid ectopic thyroid carcinoma in dogs. Vet Radiol Ultrasound 2013;54:575-581. 
14. Saridomichelakis MN, Xenoulis PG, Chatzis MK, et al. Thyroid function in 36 dogs with leishmaniosis due to Leishmania infantum before and during treatment with allopurinol with or without meglumine antimonate. Vet Parasitol 2013;197:22-28. 
15. Schaefer S, Hassa PO, Sieber-Ruckstuhl NS, et al. Characterization of recombinant human and bovine thyroid-stimulating hormone preparations by mass spectrometry and determination of their endotoxin content. BMC Vet Res 2013;9:141. 
16. Shadwick SR, Ridgway MD, Kubier A. Thyrotoxicosis in a dog induced by the consumption of feces from a levothyroxine-supplemented housemate. Can Vet J 2013;54:987-989. 
17. Simpson C, Devi JL, Whittem T. Bioavailability of two L-thyroxine formulations after oral administration to healthy dogs. Aust Vet J 2013;91:83-88. 
18. Taeymans O, Penninck DG, Peters RM. Comparison between clinical, ultrasound, CT, MRI, and pathology findings in dogs presented for suspected thyroid carcinoma. Vet Radiol Ultrasound 2013;54:61-70. 
19. Taylor BE, Leibman NF, Luong R, et al. Detection of carcinoma micrometastases in bone marrow of dogs and cats using conventional and cell block cytology. Vet Clin Pathol 2013;42:85-91. 
20. Tsuboi M, Uchida K, Ide T, et al. Pathological features of polyneuropathy in three dogs. J Vet Med Sci 2013;75:327-335. 
21. Tvarijonaviciute A, Jaillardon L, Ceron JJ, et al. Effects of thyroxin therapy on different analytes related to obesity and inflammation in dogs with hypothyroidism. Vet J 2013;196:71-75. 
22. Zeugswetter FK, Vogelsinger K, Handl S. Hyperthyroidism in dogs caused by consumption of thyroid-containing head meat. Schweiz Arch Tierheilkd 2013;155:149-152.