lecture 9/tutorial 11 - tuberculosis Flashcards
What organism causes intestinal and oropharyngeal tuberculosis?
Mycobacterium bovis
What is the Ghon complex?
The area of primary TB infection in the lungs that develops granulomas as well as the associated affected hilar lymphnodes.
What is the most common outcome of a primary TB infection?
The organism is killed, Ghon complex heals by fibrosis and the patient will be immune to TB
What type of TB is caused by haemotagenous spread of the bacteria?
Miliary TB
What is miliary TB?
Haemoatgenous spread of TB bacteria leads to lesions/granulomas forming all over multiple organs, including the lungs
Where are secondary TB lesions usually found in the lungs?
The apical parts
Why is secondary TB also called cavitary TB?
Because patients will cough up bacteria-laden casesous material leaving empty cavities in their lungs
Why will the whole lung develop lesions in secondary TB?
Necrotic material and organism will be coughed up and reinhaled into other parts of the lungs allowing the infection to spread
What type of necrosis is present in secondary TB?
Caseous (cheesy) necrosis
What are the features of a chest xray of a patient with healed primary TB?
Small region of fibrosis where there was healing/scarring of the initial ghon focus
What are the features of a chest xray of a patient with secondary TB?
Areas of fibrosis and also dark cavities with no lung markings due to formation of cavities from coughing up necrotic material
What is the disease caused by TB infection of the spinal vertebrae?
Pott’s Disease
What is the disease caused by TB infection of the renal pelvis?
Tuberculosis Pyelonephritis
What is the gross morphology of a kidney in Tuberculosis pyelonephritis?
Caseous necrosis of renal parenchuma, distended renal pelvis, narrowed ureter
What is the preferred blood test for diagnosis of active or latent TB?
Interferon-Gamma release assay (test called QuantiFERON-TB gold)
