1887

Body cavity effusions

image of Body cavity effusions
GBP
Online Access: £ 25.00 + VAT
BSAVA Library Pass Buy a pass

Abstract

Body cavity effusions occur when there is abnormal accumulation of fluid in a body cavity. In dogs and cats, effusions commonly occur in the pleural, peritoneal or pericardeal spaces. Clinical signs, such as dyspnoea, lethargy, exercise intolerance and abdominal distension, can be due to the presence of the effusion, the disease responsible for producing the effusion or both. The chapter looks at the pathophysiology of effusion formation, collection of body cavity effusions, laboratory evaluation and the classification of effusions. This chapter also includes case examples.

Preview this chapter:
Loading full text...

Full text loading...

/content/chapter/10.22233/9781910443255.chap22

Figures

Image of 22.1
22.1 (a–b) Sites for thoracocentesis. A drain enters the pleural cavity through the eighth intercostal space, just above the costochondral junction. The drain is tunnelled subcutaneously (only required for an indwelling drain). (c) Site for pericardiocentesis. In this case the sixth intercostal space is being used (see text).
Image of 22.2
22.2 The gross appearance of effusions can vary markedly and may provide additional information. Tube A: this thoracic effusion is lactescent in appearance and is chylous. Tube B: this abdominal effusion is bright yellow with a small red cell sediment; the protein findings were suggestive of feline infectious peritonitis. Tube C: this abdominal effusion appears haemorrhagic.
Image of 22.4
22.4 Reactive mesothelial cells. Cytospin (concentrated) preparation of a pleural effusion from a dog. Moderate numbers of red blood cells are present. The nucleated cells consist of neutrophils, small morphologically normal lymphocytes, occasional macrophages and low numbers of reactive mesothelial cells. The reactive mesothelial cells have a basophilic cytoplasm, glycocalyx halo and may also be multinucleate (a binucleate form is seen here). (Romanowsky stain; original magnification X500)
Image of 22.6
22.6 Transudate, protein-rich. Cytospin (concentrated) preparation of an abdominal effusion from a dog with hepatic dysfunction. A mixed population of cells, including macrophages, neutrophils and small morphologically normal lymphocytes, is commonly seen in this type of effusion. Note that this appears very cellular owing to the cytocentrifugation technique, although the cell count was low at 1.2 × 10/l. (Romanowsky stain; original magnification X200)
Image of 22.7
22.7 Septic exudate. Cytospin preparation of a thoracic effusion from a cat, in which intracellular bacteria can be seen. (Romanowsky stain; original magnification X1000)
Image of 22.8
22.8 Non-septic exudate. Cytospin preparation of a thoracic effusion from a cat. Note the markedly increased neutrophils (confirmed by an automated TNCC) consistent with an inflammatory process. There is no cytological evidence of a septic process (i.e. there is an absence of pathogenic microorganisms and their toxins). (Romanowsky stain; original magnification X200)
Image of 22.11
22.11 Chylous effusion. Cytospin preparation of a thoracic effusion from a cat. The nucleated cells are predominantly small morphologically normal lymphocytes. (Romanowsky stain; original magnification X500)
Image of 22.12
22.12 Chylous effusion. Cytospin preparation of a thoracic effusion from a cat. The macrophages contain large numbers of small vacuoles consistent with ingestion of lipid (arrowed). (Romanowsky stain; original magnification X1000)
Image of 22.13
22.13 Erythrophagocytosis. Cytospin preparation of abdominal fluid from a dog. Red blood cells have been phagocytosed by macrophased (arrowed), suggesting that red cells are less likely to be due to blood contamination at the time of sampling. (Romanowsky stain; original magnification X200) (Courtesy of JK Dunn)
Image of 22.14
22.14 Neoplastic effusion, lymphoma. (a) Cytospin preparation of a thoracic effusion from a cat. Moderate numbers of red blood cells are present. The nucleated cells consist of a population of large atypical lymphoid cells. These cells are approximately 30–50 μm in diameter, with high nuclear:cytoplasmic (N:C) ratio, fine chromatin and multiple large, prominent abnormally shaped nucleoli. (Romanowsky stain; original magnification X200). (b) Higher magnification of (a). Note that some of the bizarre nuclear morphologies can be due to the cytospin preparation. (Romanowsky stain; original magnification X500)
Image of 22.15
22.15 Neoplastic effusion, carcinoma. (a) Cytospin preparation of a thoracic effusion from a dog. Abundant red blood cells and neutrophils are present. Two cohesive clusters of very large mononuclear cells are seen; these cells appear pleomorphic. Detailed examination is hampered by the extremely basophilic nature of these cells. This animal was found to have a carcinoma on histopathology from lung tissue collected via a thoracotomy. Differentiation from mesothelioma is not always possible on cytology alone. (Romanowsky stain; original magnification X200). (b) Higher magnification of (a). Atypical large round mononuclear cells are present in a cohesive cluster which has an acinus-like formation. High N:C ratio is also discernible at this magnification. (Romanowsky stain; original magnification X500)
Image of 22.16
22.16 Neoplastic effusion, mesothelioma. (a) Cytospin preparation of a thoracic effusion from a dog. Moderate numbers of red blood cells are present, but there is no cytological evidence of inflammation. The nucleated cells consist of a pleomorphic population of large atypical mesothelial cells. Anisokaryosis is also present, and a prominent nucleolus is visible. (Romanowsky stain; original magnification X200). (b) Higher magnification of (a). Note the bizarre signet ring form on the far left of the cohesive cluster of mononuclear cells (arrowed). No cytological evidence of inflammation. (Romanowsky stain; original magnification X500)
Image of 22.17
22.17 Neoplastic pleural effusion in a cat. A population of large atypical mononuclear cells is seen, which have morphological characteristics of both lymphoid and epithelial cells. This cat was found to have a carcinoma on histopathology. (Romanowsky stain; original magnification X500)
Image of 22.18
22.18 Pericardial effusion. (a) Cytospin preparation of pericardial effusion from a dog. Abundant red blood cells are present. The mononuclear cells consist of a population of mesothelial cells showing moderate variation in cell and nuclear size. This animal was believed to have an idiopathic pericardial effusion. (Romanowsky stain; original magnification X200). (b) Pericardial effusion. Further example of reactive mesothelial cells (same case as in (a)). (Romanowsky stain; original magnification X400) (Courtesy of JK Dunn)
Image of 22.19
22.19 Schematic of clinical decision-making process which can be performed in practice in association with effusion total protein assessment. FIP = feline infectious peritonitis; PCV = packed cell volume.
Image of 22.20
22.20 Cytospin of pleural fluid. (Romanowsky stain; original magnification X400)
Image of 22.21
22.21 Gross appearance of pleural fluid.
Image of 22.22
22.22 Cytospin of pleural fluid. (Romanowsky stain; original magnification X1000)
Image of 22.23
22.23 Cytospin of peritoneal fluid. (Romanowsky stain; original magnification X1000)
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error