Introduction
- Cause : both neoplastic and non-neoplastic conditions.
- Signs : attributable to the respiratory or upper gastrointestinal tracts.
- Occasionally, mediastinal space-occupying lesions will cause head, neck or forelimb edema, or Horner's syndrome if the sympathetic ganglion is affected.
- Diagnosis : ultrasonography.
- Treatment : often symptomatic or surgical.
- Prognosis : good for abscess, foreign bodies and granulomas; fair for thymoma; poor for lymphosarcoma.
Diagnosis
Clinical signs
- Muffled heart sounds.
- Moist rales.
- Reduced compressibility of the anterior chest wall.
- Decreased thoracic resonance on percussion.
- Thoracic pain.
- Tachypnea.
- Pyrexia (if inflammatory disease).
- Peripheral lymphadenopathy in neoplastic states.
Diagnosis
Differential diagnosis
Sequelae
Prognosis
- Poor long-term for lymphosarcoma in FeLV-positive cats.
- Fair for thymoma: surgery of these benign and slow-growing tumors can be curative/palliative.
- Good for abscess/foreign bodies, granulomas and traumatic conditions if surgery is successful and supportive therapy sufficient.
Expected response to treatment
- Resolution of respiratory signs.
- Improvement in patient demeanor.
- Weight gain, improved appetite, etc.
Reasons for treatment failure
- Incorrect diagnosis, ie not mediastinal disease.
- Severe or undiagnosed underlying pathology.
- Insufficient surgical drainage or duration of antibiotic therapy in infectious conditions.
Sources
Publications
Refereed papers
- Koutinas C Ket al(2003)Caudal mediastinal abscess due to a gras awn (Hordeum spp) in a cat.J Feline Med Surg.5(1), 43-46.
- Tidwell A S (1998)Ultrasonography of the thorax (excluding the heart).Vet Clin NA28993-1015.
- Day M J (1997)Review of thymic pathology in 30 cats and 36 dogs.JSAP38393-403.
- Rogers K S and Walker M A (1997)Disorders of the mediastinum.Comp Cont Ed Pract Vet1969-83.
- Roush J Ket al(1990)Diseases of the retroperitoneal space in the dog and cat.JAAHA2647-54.
- Scott-Moncrueff J C, Cook J R and Lantz G C (1990)Acquired myasthenia in a cat with thymoma.JAVMA1961291-1293.
- Parker N R, Walker P A and Gay J (1989)Diagnosis and surgical management of esophageal perforation.JAAHA25587-594.
- Gruffydd-Jones T L, Gaskell C J, Gibbs C (1979)Clinical and radiological features of anterior mediastinal lymphosarcoma in the cat - a review of 30 cases.Vet Rec104304-307.




