This review focuses on the role of the lung microbiome in idiopathic pulmonary fibrosis. Although historically considered sterile, bacterial communities have now been well documented in lungs both in healthy and pathological conditions. Studies in idiopathic pulmonary fibrosis (IPF) suggest that increased bacterial burden and/or abundance of potentially pathogenic bacteria may drive disease progression, acute exacerbations, and mortality. More recent work has highlighted the interaction between the lung microbiome and the innate immune system in IPF, strengthening the argument for the role of both host and environment interaction in disease pathogenesis. Existing published data suggesting that the lung microbiome may represent a therapeutic target, via antibiotic administration, immunization against pathogenic organisms, or treatment directed at gastroesophageal reflux. Taken altogether, published literature suggests that the lung microbiome might serve in the future as a prognostic biomarker, a therapeutic target, and/or provide an explanation for disease pathogenesis in IPF.

Background: Idiopathic pulmonary fibrosis (IPF) affects West Highland white terriers (WHWTs). Osteopontin (SPP1) and fibronectin (FN1) are associated with human IPF and are overexpressed by bronchoalveolar lavage fluid (BALF) macrophages in dogs with IPF. Objective: To investigate the value of these proteins as biomarkers of IPF. Animals: West Highland white terriers (WHWTs) with IPF, control WHWTs, and terriers. Methods: Cross-sectional observational study. Immunohistochemistry was used to localize SPP1 and FN1 in lung tissue. Serum and BALF SPP1 and FN1 concentrations were measured using canine ELISA kits and compared between groups. Results: Osteopontin stained ciliated epithelial cells, smooth muscular cells, and macrophages of all included dogs, and type-II pneumocytes and extracellular matrix of all 12 diseased WHWTs, 4/6 control WHWTs, and none of the 3 terriers. Osteopontin serum concentration was higher in diseased WHWTs (n = 22; 2.15 ng/mL [0.74-5.30]) compared with control WHWTs (n = 13; 0.63 ng/mL [0.41-1.63]; P = .005) and terriers (n = 15; 0.31 ng/mL [0.19-0.51]; P < .0001), and in control WHWTs compared with terriers (P = .005). Osteopontin BALF concentrations were higher in diseased (0.27 ng/mL [0.14-0.43]) and control WHWTs (0.25 ng/mL [0.14-0.40]), compared with terriers (0.02 ng/mL [0.01-0.08]; P < .0001 and P = .003, respectively). Fibronectin (FN1) serum concentrations were lower in diseased dogs (1.03 ng/mL [0.35-1.48]) and control WHWTs (0.61 ng/mL [0.24-0.65]) compared with terriers (2.72 ng/mL [0.15-5.21]; P < .0001 and P = .0001, respectively). There was no difference in FN1 immunostaining and FN1 BALF concentrations between groups. Conclusions: Results suggest that SPP1 is involved in pathogenesis of IPF and could predispose that breed to the disease. Osteopontin serum concentration could serve as a diagnostic biomarker of IPF.

Background: Hemotropic mycoplasmas, hemoplasmas, are epi-erythrocytic parasitic bacteria that can be transmitted through blood transfusion. Objectives: To study the prevalence of hemoplasma infection of potential feline blood donors and investigate the association between Hemoplasma spp. quantitative polymerase chain reaction (qPCR) positivity in blood units and selected variables. Animals: Seven thousand five hundred seventy-three blood units from 4121 privately-owned potential donor cats. Methods: Retrospective observational cross-sectional study. The Banco Sangue Animal (BSA)—Animal Blood Bank medical database was reviewed for all feline donations performed in 2022 in Portugal, Spain, and Belgium. Baseline characteristics and results of blood-borne pathogens screening tests were extracted from the medical records. Results: Two hundred twelve of 4034 Portuguese donor cats and 2 of 70 Spanish donor cats tested positive for Hemoplasma spp. qPCR in 2022 leading to an overall estimated prevalence of 5.2% (95% CI: 4.5%-5.9%) in potential blood donors. Using multivariable generalized estimation equation models, Hemoplasma spp. qPCR was more often positive among blood units issued from male cats (OR = 1.9, 95% CI: 1.4-2.6, P < .0001), units positive for FeLV (OR = 2.8, 95% CI: 1.4-5.6, P = .0023), and units collected in winter months (OR = 2.5, 95% CI: 1.7-3.6, P < .0001). Conclusions and Clinical Importance: This study underscores the importance of Hemoplasma spp. and other relevant blood-borne pathogens screening at every donation. Implementing stringent screening protocols is crucial to mitigate the risk of hemoplasma transmission via blood transfusions, thereby safeguarding the health and welfare of cats receiving transfusions.

Background: Canine idiopathic pulmonary fibrosis (CIPF) is a progressive interstitial lung disease mainly affecting old West Highland white terriers (WHWTs). The aetiology of CIPF is currently unknown and pathogenesis poorly understood. A genetic basis is strongly suspected based on the breed predisposition. CIPF shares clinical and pathological features with human IPF. In human IPF, coagulation disorders favouring a local and systemic pro-thrombotic state have been demonstrated in association with disease severity and outcome. The aim of this study was to compare the systemic haemostatic, fibrinolytic and inflammatory profiles of WHWTs affected with CIPF with breed-matched controls (CTRLs). Additionally, data collected in both groups were interpreted with regard to the reference intervals (when available) to assess possible pro-thrombotic features of the WHWT breed that may be related to CIPF predisposition. A total of 14 WHWTs affected with CIPF and 20 CTRLs were included. Results: WHWTs affected with CIPF had prolonged activated partial thromboplastine time in comparison with CTRLs (12.2 ± 0.9 s vs. 11.5 ± 0.7 s, P = 0.028), whereas results obtained in both groups were all within reference ranges. There was no significant difference between groups for the other factors assessed including plasmatic concentrations of fibrinogen, D-dimers concentration, antithrombin III activity, protein S and protein C activities, anti-factor Xa activity, activated protein C ratio, serum C-reactive protein concentration, and rotational thromboelastometry indices. Platelet count and plasmatic fibrinogen concentration were found to be above the upper limit of the reference range in almost half of the WHWTs included, independently of the disease status. Conclusions: Results of this study provide no clear evidence of an altered systemic haemostatic, fibrinolytic or inflammatory state in WHWTs affected with CIPF compared with CTRLs. The higher platelet counts and fibrinogen concentrations found in the WHWT breed may serve as predisposing factors for CIPF or simply reflect biological variation in this breed.

Canine idiopathic pulmonary fibrosis (CIPF) is an interstitial lung disease reported in West Highland white terriers (WHWTs). B-mode ultrasonography (US) is used in human medicine as an adjunct tool for interstitial lung disease, including idiopathic pulmonary fibrosis. In veterinary medicine, thoracic US has been described as helpful for the diagnosis of various pulmonary diseases. The aim of this study was to describe the thoracic B-mode US findings in CIPF WHWTs, compared with those in control WHWTs. Twenty-seven WHWTs, including CIPF and control WHWTs, were prospectively enrolled. Standardised thoracic B-mode US was performed. The presence of an irregular pleural surface, ring-down artefact and peripheral nodules was assessed and scored for each location. An overall cumulative score was calculated by adding the individual scores of each location. WHWTs affected with CIPF had significantly higher overall scores compared to the control group. The ring-down artefact score was significantly higher in the CIPF group compared to the control group. No preferential location for the lesions was observed. A cut-off value of 15 ring-down artefacts for the entire thorax predicted CIPF in WHWTs with a sensitivity of 76.5% and a specificity of 80% (AUC 0.815). The present study describes B-mode US findings in CIPF WHWTs.