This research article investigates how different staining methods might affect the diagnosis of non-infectious lower airway inflammation in donkeys using bronchoalveolar lavage fluid (BALF) cytology, with the goal of determining which method is the most accurate.

Research Objective

• The main purpose of this study is to compare the outcome of cytology tests on BALF in donkeys using four different staining methods: Diff-Quick (DQ), modified May-Grunwald Giemsa (mMGG), Toluidine Blue (TB), and Perls Prussian blue (PPB). The comparisons aim to determine the accuracy and possible discrepancies when these four different staining methods are used.

Methodology

• In the study, nine healthy female Amiata donkeys were used and subjected to the BAL procedure. Cytocentrifuged BALF samples were stained using the four above-mentioned methods.
• The study sought to observe the differences in macrophages, mast cells, neutrophils, eosinophils, and hemosiderophages, the primary cell types that comprise BALF, by comparing differential counts across the four staining methods.

Results

• The results indicated that no significant differential count discrepancies existed among the macrophages, neutrophils, and eosinophils in both mMGG and DQ staining methods.
• The mast cell count, however, showed a difference when DQ was compared to TB. But no significant differences were noted when comparing mMGG to DQ and mMGG to TB for mast cells.
• Also, the study found no differences in hemosiderophages’ differential count when comparing mMGG, DQ, and PPB staining methods.
• The researchers concluded that mMGG appears to be the most effective stain for identifying all cell types in BALF, including mast cells, among donkeys, preventing possible misidentification of cells.

Conclusion and Implications

• The comparison implies that solely using the DQ staining method may cause inappropriate identification of mast cells. Thus, mMGG is suggested as the preferred staining method when diagnosing non-infectious lower airway inflammation in donkeys.
• These findings are consistent with previous literature on BALF staining methods used in horses, emphasizing the relevance and applicability of the results.