Mycobacteria testing

We provide a series of test help in the workup of suspected mycobacteriosis in cats and dogs.

We provide a range of tests to support the investigation of suspected mycobacteriosis in cats and dogs, including Interferon Gamma Release Assay (IGRA), haematology, biochemistry, acute phase proteins, histology, cytology and special stains.

Results are normally issued within seven days of sample receipt. 

For clinical advice and patient referral, please see the ‘Advice & Referral’ section of the Mycobacteria Resources page on the Hospital for Small Animals website. 

Mycobacteria Resources

For an up-to-date price list please get in touch:

Mycobacteria are pathogens of global health significance in both human and non-human animals. In cats, mycobacterial infection is uncommon and is generally divided into tuberculous disease, caused by the Mycobacterium tuberculosis complex (mainly M. bovis and M. microti), and non-tuberculous mycobacteriosis, caused by environmental mycobacteria (mainly the M. avium complex). Despite the relatively low risk, all forms of mycobacteriosis have zoonotic potential. 

Mycobacteriosis in dogs appears to be far less common than in cats; however, the clinical severity and zoonotic potential are much greater. Further details on clinical presentation, a diagnostic flow chart and treatment can be found in the Mycobacteria resources page on the Hospital for Small Animal website.

 Mycobacteria Resources


Routine haematology and serum biochemistry testing may reveal non-specific changes, but these investigations are still recommended to assess the patient’s overall health status, identify comorbidities, and monitor changes over time. 

Specific investigations for suspected mycobacterial infection include histopathology/cytology with Ziehl–Neelsen staining, PCR, Interferon Gamma Release Assay (IGRA) on blood samples, and specialist culture. 

More details on diagnostic options and recommendations can be found on the Mycobacteria resources webpage. 

Mycobacteria Resources

Easter Bush Pathology, in collaboration with the Immunology Team of the Roslin Institute, offers a range of tests to support the investigation of suspected mycobacteriosis cases. 

TestSample requirement
IGRA (Interferon Gamma Release Assay)  2 ml whole blood in lithium heparin
Routine haematology including pathologist smear report  0.5 ml EDTA, blood smear 

Mycobacteria serum biochemistry:

(Total protein, albumin, globulin, A/G ratio, ALT, ALP, GGT, total bilirubin, creatinine, urea, total calcium, Na, K, Cl, Vet-SAA, AGP (cats only), CRP (dog only))  

0.5 ml serum 

Mycobacteria haematology and biochemistry profile:  

(Routine haematology with pathologist smear report and mycobacteria serum biochemistry) 

0.5 ml EDTA + 0.5 ml serum

Acute phase proteins

(e.g., Vet-SAA, Feline AGP, Canine CRP)

0.5 ml serum  
Cytology Cytology smears

Cytology Fluid Analysis 

(cell count, total proteins, cytology) 

0.5 ml EDTA fluid, smears 

Histopathology 

(use specific histology submission form) 

Formalin fixed tissue
Ziehl–Neelsen Stain  Cytology smears or tissue sections. Can be run on pre-stained cytology slides.

See the complete list of diagnostic tests offered by Easter Bush Pathology by following the link below:

Diagnostic services offered by Easter Bush Pathology


The Interferon Gamma Release Assay (IGRA) is an immunological assay used to assess cell-mediated immune responses to mycobacterial antigens. Following stimulation with specific antigens, sensitised lymphocytes release interferon-gamma, which is measured to assess exposure to members of the Mycobacterium tuberculosis complex (MTBC) and other mycobacterial organisms. 

IGRA supports the diagnosis of feline and canine mycobacterial disease. The test can help indicate whether infection is likely to be caused by Mycobacterium bovis - a common cause of tuberculosis [TB] in cats and dogs, M. microti - a major cause of TB in cats and, occasionally, in dogs, or other Mycobacterium species. M. bovis, and occasionally M. microti, pose a low but potential zoonotic risk to humans. 

  • IGRA testing is performed weekly on Thursdays 
  • The test is time-sensitive and requires a minimum of 2 ml of fresh (preferably 24h, max 48h old) whole blood collected into lithium heparin (LH) tubes
  • Results are normally issued within seven days of sample receipt
  • A small processing fee will be charged for samples that are unsuitable for analysis. 

Sampling protocol

  • Collect a minimum of 2 ml of whole blood in lithium heparin tubes on a Tuesday or Wednesday 
  • Keep samples at room temperature. Do not centrifuge, refrigerate or freeze
  • Triple-package samples in accordance with standard biological sample procedures. If sending samples for additional laboratory tests, place the lithium heparin sample for IGRA in a separate sealed bag
  • Include the Mycobacteriosis Submission Form and send samples to Easter Bush pathology by next-day or overnight delivery.  
  • Samples must arrive at the laboratory by noon on Thursday. 

Easter Bush Pathology

Contact details

Address

University of Edinburgh
Easter Bush campus
Roslin
Midlothian
EH25 9RG

Availability

The laboratory is open 9am-5pm Monday to Friday including public holidays, except for 25 and 26 December and 1 and 2 January.

This article was published on