Comparison of thyrotropin concentrations measured by bulk acoustic wave technology and chemiluminescence in hyperthyroid cats and cats with non-thyroidal illness
Year: 2025
Type: article
Abstract: Objectives A thyrotropin (also known as thyroid-stimulating hormone [TSH]) assay using bulk acoustic wave (TSH-BAW) technology is a sensitive and specific test for diagnosing hyperthyroidism; however, the effect of various types of non-thyroidal illness (NTI) have not been evaluated with this assay. The objectives of this study were to compare serum TSH concentrations using the TSH-BAW and a currently available TSH chemiluminescent immunoassay (TSH-CLIA) in hyperthyroid cats, cats with NTI and healthy cats, as well as to compare sensitivity and specificity for diagnosing hyperthyroidism. Methods A prospective cross-sectional study was conducted comparing the TSH concentration of 37 hyperthyroid, 32 healthy and 32 NTI cats using the TSH-CLIA and TSH-BAW assays. The effect of disease severity was evaluated with hyperthyroidism and NTI. Results The TSH-BAW had a lower sensitivity (78%, 95% confidence interval [CI] 62–90) and negative predictive value (89%, 95% CI 79–95) but higher specificity (97%, 95% CI 89–100) and positive predictive value (94%, 95% CI 79–99) than the TSH-CLIA. The median serum TSH concentration was significantly different between hyperthyroid cats and both healthy and NTI cats with both assays ( P <0.01) but was not different between NTI and healthy cats (TSH-CLIA P = 0.168, TSH-BAW P = 0.673). Eight (21.6%) hyperthyroid cats had a detectable TSH-BAW but undetectable TSH-CLIA concentration, with seven (18.9%) having a TSH-BAW within the reference interval. A total of 12 (18.8%) non-hyperthyroid cats (four [12.5%] healthy cats and eight [25%] NTI cats) had an undetectable TSH-CLIA compared with only two (6%) cats (one [3%] healthy cat and one [3%] NTI cat) with the TSH-BAW assay. The proportion of cats with an undetectable serum TSH concentration was significantly higher with the TSH-CLIA than the TSH-BAW in NTI cats ( P = 0.008). This was especially evident in NTI cats suffering from moderate to severe illnesses ( P = 0.025). Conclusions and relevance The TSH-BAW has a high specificity for detecting hyperthyroidism and identifies a normal serum TSH concentration in non-hyperthyroid cats more often than the TSH-CLIA. However, a normal result cannot be used to rule out hyperthyroidism.
Language: English
Subfield: Small Animals
Field: Veterinary
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,800
OpenAlex ID: W4416143383