Diagnostic challenge: mare with clinical history of chronic respiratory disease

Abstract

Section 1Clinical history and physical examination A 430-kg 15-year-old Australian Stockhorse mare was referred to the Veterinary Clinical Centre (VCC), Charles Sturt University, for investigation of a 6-week history of clinical signs of respiratory disease and weight loss and no response to administration of systemic antimicrobials. Clinical signs included coughing on exertion and increased rate and effort of respiration. Clinicopathological abnormalities detected by the referring veterinarian included anaemia and hyperfibrinogenaemia.On presentation to the VCC, the mare was lethargic and had a rectal temperature of 39.8°C. Wheezes and crackles were audible over the left and right hemithoraces. The mare was tachypnoeic with increased respiratory effort, especially during inspiration. Distal limbs were oedematous, and the mare was moderately thin (body condition score 4/9). Ancillary testsA complete blood count and blood biochemistry revealed a mild to moderate anaemia (packed cell volume (PCV) 0.20L/L, reference range 0.32-0.52 L/L), a mild left shift with normal neutrophil number (segmented neutrophils 4.8 × 10 9 /L, band neutrophils 0.3 × 10 9 /L, reference range 2.5-8.0 × 10 9 /L and 0.0-0.2 × 10 9 /L respectively), a moderate to marked hyperfibrinogenaemia (10 g/L, reference range 0-4 g/L) and a mild hypoalbuminaemia (24 g/L, reference range 28-38 g/L). A transendoscopic tracheal wash (TW) was performed and cytological examination of the obtained sample showed 85% neutrophils (reference range <20%) and small to moderate numbers of Curschmann's spirals. Arterial blood gas analysis revealed a partial pressure of oxygen of 71 mmHg (normal >98 mmHg) and oxygen saturation of 94% (normal >95%).

Gammaherpesvirus infections in equids: a review

“…The majority of cases of the disease have been in middle-aged and older horses, but it should also be noted that EMPF has been diagnosed in horses younger than 2 years. 85 , 141 , 147 , 149 , 161 However, the disease is more severe in older horses, 155 akin to what has been reported with other γ-HVs, like murine γ-herpesvirus 68. 162 …”

“…Considering its as yet undefined etiology, the treatment of EMPF is not definitive and largely symptomatic. 160 , 161 Corticosteroids are advocated to suppress pulmonary inflammation by inhibiting the synthesis of inflammatory cytokines and mediators that promote fibrosis and cellular infiltration. Antimicrobial therapy is generally recommended to prevent bacterial superinfection.…”

Review of glucocorticoid therapy in horses. Part 2: Clinical use of systemic glucocorticoids in horses

“…; Kessell et al . ). Since an infectious organism is often the cause of multinodular pulmonary fibrosis in horses, glucocorticoid therapy is sometimes avoided due to its immunosuppressive effects; however, inhibition of the inflammatory response is a key factor to avoid irreversible damage to the lung (Niedermaier et al .…”

In this issue – January/February 2014

“…The equine paper this month is in the format of a diagnostic challenge . Although these submissions do not necessarily relate to novel conditions, they are all peer reviewed in the usual way and the quality of images is paramount.…”