Acute phase proteins in cats: Diagnostic and prognostic role, future directions, and analytical challenges

Abstract

While clinical studies on acute phase proteins (APPs) have significantly increased in the last decade, and most commercial labs are now offering major APPs in their biochemical profiles, APP testing has not been widely adopted by veterinary clinical pathologists and veterinarians. Measurement of APP concentration is a useful marker for detecting the presence or absence of inflammation in cats with various diseases. APPs can also be reliably measured in different biological fluids (eg, effusions and urine) to improve their diagnostic utility. Measurement of APPs can be extremely beneficial in cats with feline infectious peritonitis (FIP) to discriminate between FIP and non‐FIP cats with similar clinical presentations. Additional benefits come from multiple and sequential measurements of APPs, particularly in the assessment of therapeutic efficacy. APPs are more sensitive than WBC counts for early detection of inflammation and to demonstrate an early remission or recurrence of the diseases. Given the potential utility of APPs, more studies are warranted, with a particular focus on the applications of APPs to guide the length of antimicrobial therapies, as suggested by the antimicrobial stewardship policy. New inflammatory markers have been discovered in human medicine, with a higher specificity for distinguishing between septic versus nonseptic inflammatory diseases. It is desirable that these new markers be investigated in veterinary medicine, to further test the power of APPs in diagnostic setting.

Akute-Phase-Proteine bei Hund und Katze – Was sind sie, wozu dienen sie und was gibt es Neues?

“…Obwohl die Sensitivität und Spezifität von SAA für die Erkennung systemischer Entzündungen bei Katzen generell hoch sind, liefert eine Erhöhung der SAA-Konzentration meistens auch bei dieser Tierart keine definitive Diagnose . Mithilfe von SAA kann man nicht mit Sicherheit septische Katzen von denen ohne Sepsis unterscheiden 14 . Zur Diagnose mittels SAA sind bei hypertropher Kardiomyopathie, Diabetes mellitus und Hyperthyreose widersprüchliche Aussagen zu finden.…”

Introducing the special issue on acute phase proteins in veterinary medicine

“…Across all species, APPs have been demonstrated to be more sensitive in the detection of inflammation than WBC counts and also have key prognostic value. In cats, Rossi has provided a summary of this application, inclusive of pancreatitis, chronic gingivostomatitis, and feline lower urinary tract disease 2 . While increases are observed in many different inflammatory conditions, consistent increases in the moderate APP α‐1‐acid glycoprotein can be observed in cats diagnosed with feline infectious peritonitis rather than other conditions resulting in peritoneal effusion.…”