2.3.2 Plasma fibrinogen
Plasma fibrinogen is an acute-phase protein which is raised in animals with inflammatory foci. The exact values depend on the assay used and should be referred to each individual laboratory's normal range. As a general rule, infecconditions result in particularly high fibrinogen levels. Measurement of plasma fibrinogen is worthwhile in many cases, particularly when endocarditis is suspected. This condition is usually accompanied by a markedly elevated plasma fibrinogen, often in excess of 8 gA. Fibrinogen assays are a useful screening process which can alert the clinician to the possible presence of an infected focus. This is important because successful treatment of endocarditis requires aggressive use of antibiotics early in the course of the disease. However, it should be remembered that plasma fibrinogen may also be raised in other inflammatory diseases which may complicate heart disease. For example, some horses with pulmonary oedema develop a secondary pneumonia which will result in a raised fibrinogen. Serial fibrinogen assays are helpful for monitoring the progress of inflammatory disease in response to treatment.