CMAN 380 Final Exam Study Guide with complete
solution
goal of epidemiology`
to improve health outcomes in a population
rate
number of events/populations at risk x 100,000
incidence
number of new cases of an illness/injury that occurs within a specific time
prevalence
measures all of the existing cases at a given point in time
prospective study
establishes a causal association and a temporal relationship, all subjects are free of
disease, data is collected over time
retrospective study
does NOT establish a causal association, investigators go back in time to study a
population that was at risk (subjects have already has the illness/injury)
confounding factor
variable that effects both the exposure and the outcome; must be identifiable to account
for what may impact the direct and indirect variables
evidenced based research
taking findings from studies and implementing them into practice
pathogenesis
how an infection or disease develops in the body/chain of events leading to the disease
tuberculosis transmission
droplet nuclei (airborne)
latent TB
occurs when the tubercle bacilli are in the body but the immune system is keeping them
under control
active TB
develops when the immune system cannot keep tubercle bacilli under control
conditions that increase the probability of a person with latent TB to develop
active TB
- HIV
- substance abuse
- recent TB infection
- prolonged corticosteroid or immunosuppressive therapy
- organ transplant
- silicosis
- diabetes mellitus
- severe kidney disease
- certain types of cancer
- certain intestinal conditions
- low body weight
the ways in a person infected with HIV can develop TB
, 1. person with latent TB contracts HIV and in turn develops active TB as a result of a
weakened immune system
2. a person with HIV becomes infected with TB and rapidly develops active TB
pulmonary TB
tubercle bacilli are located in the lungs
extrapulmonary TB
tubercle bacilli are located in areas of the body that are not the lungs
military TB
tubercle bacilli is carried to all parts of the body via bloodstream
populations more susceptible to extrapulmonary TB
- HIV patients
- immunosuppressed patients
- young children
high risk groups for developing TB
- foreign born/immigrants
- Eastern European, Latin America
- low income and homeless
- congregate and residential settings i.e. nursing homes, correctional facilities,
healthcare facilities, homeless shelters, drug treatment centers
TB symptoms
- unexplained weight loss
- loss of appetite
- night sweats
- fever
- fatigue
pulmonary TB symptoms
- coughing for >/- 3 weeks
- hemoptysis
- chest pain
mantoux tuberculin skin test (TST/PPD)
0.1 ml of 5 tuberculin units are injected between the layers of skin on the forearm,
forearm should be examined within 48-72 hours of injection
two types of IGRA tests
Quantiferon TB Gold In-Tube Test and T-SPOT
advantages of IGRA
- requires single patient visit
- results can be available in 24 hours
- does not cause booster phenomenon
- less likely to have an incorrect reading of results
- BCG vaccination does not affect results
disadvantages of IGRA
- blood samples must be processed within 8-30 hours
- errors in running and interpreting test can decrease accuracy
- limited data in its use in certain populations i.e. children <5 years, those recently
exposed to TB, immunocompromised patients, serial testing
patient populations that should receive IGRA
solution
goal of epidemiology`
to improve health outcomes in a population
rate
number of events/populations at risk x 100,000
incidence
number of new cases of an illness/injury that occurs within a specific time
prevalence
measures all of the existing cases at a given point in time
prospective study
establishes a causal association and a temporal relationship, all subjects are free of
disease, data is collected over time
retrospective study
does NOT establish a causal association, investigators go back in time to study a
population that was at risk (subjects have already has the illness/injury)
confounding factor
variable that effects both the exposure and the outcome; must be identifiable to account
for what may impact the direct and indirect variables
evidenced based research
taking findings from studies and implementing them into practice
pathogenesis
how an infection or disease develops in the body/chain of events leading to the disease
tuberculosis transmission
droplet nuclei (airborne)
latent TB
occurs when the tubercle bacilli are in the body but the immune system is keeping them
under control
active TB
develops when the immune system cannot keep tubercle bacilli under control
conditions that increase the probability of a person with latent TB to develop
active TB
- HIV
- substance abuse
- recent TB infection
- prolonged corticosteroid or immunosuppressive therapy
- organ transplant
- silicosis
- diabetes mellitus
- severe kidney disease
- certain types of cancer
- certain intestinal conditions
- low body weight
the ways in a person infected with HIV can develop TB
, 1. person with latent TB contracts HIV and in turn develops active TB as a result of a
weakened immune system
2. a person with HIV becomes infected with TB and rapidly develops active TB
pulmonary TB
tubercle bacilli are located in the lungs
extrapulmonary TB
tubercle bacilli are located in areas of the body that are not the lungs
military TB
tubercle bacilli is carried to all parts of the body via bloodstream
populations more susceptible to extrapulmonary TB
- HIV patients
- immunosuppressed patients
- young children
high risk groups for developing TB
- foreign born/immigrants
- Eastern European, Latin America
- low income and homeless
- congregate and residential settings i.e. nursing homes, correctional facilities,
healthcare facilities, homeless shelters, drug treatment centers
TB symptoms
- unexplained weight loss
- loss of appetite
- night sweats
- fever
- fatigue
pulmonary TB symptoms
- coughing for >/- 3 weeks
- hemoptysis
- chest pain
mantoux tuberculin skin test (TST/PPD)
0.1 ml of 5 tuberculin units are injected between the layers of skin on the forearm,
forearm should be examined within 48-72 hours of injection
two types of IGRA tests
Quantiferon TB Gold In-Tube Test and T-SPOT
advantages of IGRA
- requires single patient visit
- results can be available in 24 hours
- does not cause booster phenomenon
- less likely to have an incorrect reading of results
- BCG vaccination does not affect results
disadvantages of IGRA
- blood samples must be processed within 8-30 hours
- errors in running and interpreting test can decrease accuracy
- limited data in its use in certain populations i.e. children <5 years, those recently
exposed to TB, immunocompromised patients, serial testing
patient populations that should receive IGRA
