ISSN 2398-2985      

Cytology: respiratory tract

Jreptile

Synonym(s): Bronchoalveolar, Tracheal wash cytology


Overview

  • Used to obtain cells and secretions to identify the cause of respiratory tract disease by cytology and microbiology.
  • Sample may be obtained in a conscious reptile by a transtracheal wash (transoral or percutaneously) Transtracheal wash, or under anesthesia through an endotracheal tube, or by endoscopy Endoscopy overview.
  • Used where there are respiratory clinical signs and evidence on diagnostic imaging of tracheal or bronchoalveolar disease to evaluate pathology, and to assist in therapeutic choices.

Sampling

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Tests

Methodologies

  • Direct smears (helpful if made at time of collection) and centrifuged preparations.
  • Cytospin or centrifuged preparations are made at 1000 rpm (slow speed) for 5 min.
  • Romanowsky stains commonly used for air-dried preparations.
  • Light microscopy.

Validity

Sensitivity

  • Variable depending on degree of inflammation, type of condition, and whether or not a representative specimen has been obtained.
  • A representative specimen of lower airway disease is more likely to be obtained from BAL than from a tracheal wash.
  • Neoplasia will only be detected if neoplastic cells have eroded the bronchiolar/alveolar surface, and exfoliated into the respiratory lumen.

Specificity

  • Variable depending on degree of inflammation, type of condition, and whether or not a representative specimen has been obtained.
  • Bacterial cultures should be interpreted with caution if the cytologist has identified evidence of oropharyngeal contamination.
  • The presence of large numbers of columnar respiratory epithelial cells in a BAL indicates that a portion of the sample has been collected from the tracheal region and might not necessarily reflect the bronchiolar-alveolar region.
  • Phagocytosis of bacteria, cell fragments and erythrocytes can occur in transit, this may increase the risk of cytological misinterpretation.
  • Marked dysplasia secondary to irritation or inflammation may mimic neoplasia.

Technique (intrinsic) limitations

  • No information is obtained regarding tissue architecture or presence/absence of fibrosis.
  • A transtracheal wash is a blind procedure and may not be representative of the lower airways.
  • The BAL procedure, when blindly performed, may miss focal lesions.
  • Pathology/neoplasia that has not eroded alveoli/small bronchioles will not exfoliate into lumen.
  • Fine needle aspiration of lung parenchyma carries a significantly greater risk, but it may be necessary in poorly exfoliative lesions that do not involve the bronchial tree.

Technician (extrinsic) limitations

  • Oropharyngeal contamination when sampling via endotracheal tube; some may occur with endoscopic sampling.
  • Hypotonic wash solution may cause cell lysis - use isotonic saline or PBS instead.
  • Hemorrhage associated with poor bronchoscope technique.
  • Excessive wash volume.

Result Data

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMed Resource.
  • Schumacher J (2003) Reptile respiratory medicine. Vet Clin North Am Exotic Anim Pract 6 (1), 213-31.

Other sources of information

  • Campbell T W (2015) Normal Herptile (Reptiles and Amphibian) Cytology. In: Exotic Animal Hematology and Cytology. 4th edn. Wiley-Blackwell. pp 229.
  • Campbell T W (2006) Clinical Pathology of Reptiles. In: Reptile Medicine and Surgery. 2nd edn. Ed: Mader D R. Saunders-Elsevier, USA. pp 453–470.

Reproduced with permission from Terry W Campbell: Exotic Animal Hematology and Cytology © 2015, published by John Wiley & Sons.

Related Images

Want more related items, why not
contact us

MEMBER BENEFIT

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!

 
 
 
 

To show you are not a Bot please can you enter the number showing adjacent to this field

 Security code