Clinical, hematological, radiographic, and conventional and elastographic ultrasonographic aspects of the lung and pleura in dogs exposed to tobacco smoke

This study evaluated the clinical, hematological, radiographic, B-mode ultrasonographic, and shear-wave elastographic (SWE) characteristics of dogs exposed to tobacco smoke. Seventy dogs were included: 33 unexposed controls (CG) and 37 tobacco smoke-exposed dogs (EG). Clinical and hematological assessments, hair nicotine quantification by liquid chromatography-tandem mass spectrometry, thoracic radiography, pulmonary ultrasonography, and SWE were performed. The EG showed a higher frequency of respiratory clinical signs and higher neutrophil and monocyte counts, total plasma protein and hair nicotine concentrations than the CG (P < 0.05). Hair nicotine concentration correlated positively with respiratory clinical manifestations, elastographic findings, and Fagerström Test scores (P < 0.05). SWE demonstrated greater pleuropulmonary interface stiffness in the EG, with higher shear-wave velocity (3.89 vs. 3.45 m/s for controls) and predominantly green elastograms compared with predominantly blue elastograms in the CG (P < 0.05). Radiographic and B-mode ultrasonographic findings did not differ between groups (P > 0.05), with regular pleuropulmonary surfaces, preserved lung sliding, no B-lines, pleural effusion, or masses, and an interface thickness of 0.05 cm. These findings indicate that tobacco smoke exposure in dogs was associated with clinical and laboratory alterations and increased pleuropulmonary interface stiffness, despite the absence of conventional imaging abnormalities that needs attention for public health and type of detection lesions caused by smoking subjects and public around them.