Statistics from Altmetric.com
EXERCISE-INDUCED pulmonary haemorrhage (EIPH) is an important respiratory disease reported to impact racing performance in horses (Hinchcliff and others 2015). Various methods have been described for diagnosing EIPH, including endoscopic detection of tracheal blood after exercise, or cytological evaluation of bronchoalveolar lavage (BAL) fluid. The former is the most frequently used diagnostic method, whereas the latter is reported to be more sensitive (Sullivan and Hinchcliff 2015). Indeed, BAL allows detection of microscopic bleeding and identification of haemosiderophages, that is, alveolar macrophages containing haemosiderin (an iron-storage complex produced by digestion of erythrocytes). In humans, haemosiderophages are detected 50–72 hours after natural or experimentally induced haemorrhage (Sherman and others 1984), and might persist for up to one month in the airways following a single episode (Gosselin and others 1989). In contrast, erythrocytes are no longer detectable within the airways after 7–10 days post exercise (Meyer and others 1998, Doucet and Viel 2002).
Two cytological staining methods, namely May-Grünwald-Giemsa (MGG) and Perls' Prussian Blue (PPB), have been described for identification of haemosiderophages in BAL fluid. MGG is a conventional method used for the morphological assessment of cell populations in blood and fluids, and commonly recommended for BAL fluid evaluation (Richard and others 2010). PPB is specifically used to detect cellular iron contents. Proportions of haemosiderophages among alveolar macrophages (H/M) and …