In:
Journal of Veterinary Internal Medicine, Wiley, Vol. 31, No. 6 ( 2017-11), p. 1643-1648
Abstract:
Thyrotropin (TSH) can be increased in humans with primary hypoadrenocorticism (HA) before glucocorticoid treatment. Increase in TSH is a typical finding of primary hypothyroidism and both diseases can occur concurrently (Schmidt's syndrome); therefore, care must be taken in assessing thyroid function in untreated human patients with HA. Objective Evaluate whether alterations in cTSH can be observed in dogs with HA in absence of primary hypothyroidism. Animals Thirty dogs with newly diagnosed HA, and 30 dogs in which HA was suspected but excluded based on a normal ACTH stimulation test (controls) were prospectively enrolled. Methods cTSH and T4 concentrations were determined in all dogs and at selected time points during treatment (prednisolone, fludrocortisone, or DOCP) in dogs with HA. Results cTSH concentrations ranged from 0.01 to 2.6 ng/mL (median 0.29) and were increased in 11/30 dogs with HA; values in controls were all within the reference interval (range: 0.01–0.2 ng/dL; median 0.06). There was no difference in T4 between dogs with increased cTSH (T4 range 1.0‐2.1; median 1.3 μg/dL) compared to those with normal cTSH (T4 range 0.5‐3.4, median 1.4 μg/dL; P =0.69) and controls (T4 range 0.3‐3.8, median 1.8 μg/dL; P =0.35). After starting treatment, cTSH normalized after 2–4 weeks in 9 dogs and after 3 and 4 months in 2 without thyroxine supplementation. Conclusions and Clinical Relevance Evaluation of thyroid function in untreated dogs with HA can lead to misdiagnosis of hypothyroidism; treatment with glucocorticoids for up to 4 months can be necessary to normalize cTSH.
Type of Medium:
Online Resource
ISSN:
0891-6640
,
1939-1676
DOI:
10.1111/jvim.2017.31.issue-6
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
2177690-8
SSG:
22
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