Fever of unknown origin in the horse: a review of 63 cases

Abstract

Summary Fever of unknown origin (FLO) is a syndrome characterised by prolonged, unexplained fever associated with non‐specific signs of illness such as lethargy, inappetence and weight loss. This paper reviews the details of 63 horses affected by FUO. The cause was found to be infection in 43 per cent of the cases, neoplasia in 22 per cent, immune‐mediated diseases in 6.5 per cent and miscellaneous diseases in 19 per cent the cause remained undiagnosed in 9.5 per cent.

Mesothelioma of the pleural cavity in a horse: diagnostic features

“…For example, pyrexia, neutrophilia and hyperfibrinogenaemia are frequently present. These features are non-specific and can be present in both infective and neoplastic diseases (Mair and Lane 1989;Mair, Taylor and Pinsent 1989).…”

Clinical Approach to Commonly Encountered Problems

“…It is considered a cardinal sign of infection and has been associated with infections caused by essentially all types of organisms. 66 The most common cause was found to be infection, which was responsible for 43% of the cases. In addition to infection, fever can be a prominent component of many inflammatory, neoplastic, and immunologic conditions.…”

Clinical Approach to Commonly Encountered Problems

“…In a review of 63 cases of fever of unknown origin in the horse, the specific criteria used to define fever of unknown origin included (1) illness of at least 3 weeks' duration associated with nonspecific signs, (2) body temperature of at least 38.6°C (101.5°F) on several occasions, and (3) no clear diagnosis after an initial complete blood count and serum biochemical profile. 66 The most common cause was found to be infection, which was responsible for 43% of the cases. Other causes included neoplasms in 22% of cases; immunemediated diseases in 6.5%; and miscellaneous diseases such as toxic hepatopathy, parasitism, and others in 19%.…”