Analytical validation and evaluation of the effects of intramuscular injections on acute phase proteins in horses

Acute phase protein (APP) measurement can be used to characterize and detect inflammation, as well as monitor response to therapy. Intramuscular (IM) injections often result in local swelling and inflammation, which may lead to increased plasma concentrations of APP. The first objective of this study was to determine whether equine plasma haptoglobin (HAP) concentrations could be measured reliably with an immunoturbidimetric assay developed for use in humans. Within run and between run imprecisions were evaluated by multiple measurements of equine plasma samples with high, intermediate, and low HAP concentrations. Assay inaccuracy was determined by linearity under dilution. In plasma samples with high, intermediate, and low HAP concentrations, the within run imprecisions were 3.13%, 1.89%, and 1.76%, and the between run imprecisions were 2.77%, 1.45%, and 1.21%. Acceptable linearity within a range of 7-122 mg/dL was observed. The detection limit was 0 mg/dL. No clinically significant interference was observed from hemoglobin, lipids, or bilirubin. In conclusion, equine HAP concentrations can be measured reliably up to 122 mg/dL using the immunoturbidimetric assay designed for human HAP. The second objective was to evaluate the possible effects of IM procaine penicillin G (PPG) injections on plasma concentrations of selected APP, including fibrinogen (FIB), serum amyloid A (SAA), and HAP, as well as on the activity of selected enzymes, including creatine kinase (CK) and aspartate aminotransferase (AST). The plasma concentrations of the aforementioned variables were evaluated for 5 consecutive days prior to drug administration (days -5 to -1), during a 5-day course of PPG administered twice daily at a recommended therapeutic dose (days 0 to 4), and for 20 days following the final injection (days 5 to 24). Results showed a significant increase in CK activity on days 1-6 and an increase in AST activity on days 2-7 and 10. A significant increase in plasma FIB was noted on days 6-8 and 10, and SAA on day 6. No significant changes in HAP were observed. These findings indicate that muscle injury caused by PPG injections may result in increased CK and AST activity and increased plasma concentration of a subset of APP including FIB and SAA.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

VMS-Veterinary Clinical Medcne

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2020

Author dc:creator

• Gordon, Danielle Louise

Contributors dc:contributor

• Foreman, Jonathan H
• Barger, Anne M
• Schnelle, Amy N
• Connolly, Sara L
• Fan, Timothy M

• Acute phase protein
• Acute phase response
• equine
• horse
• inflammation
• intramuscular injection
• method validation

Statement dc:rights

• Copyright 2020 Danielle Gordon

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/108097

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/108097