Tuberculosis Flashcards
What is Tuberculosis
- Infectious bacterial disease caused by Mycobacterium tuberculosis.
What organ(s) does TB affect
- Primarily affects the lungs but can involve other organs like: kidneys, brain (meninges), bones, adrenal glands, and lymph nodes.
What are 3 factors contributing to Multi-Drug Resistant (MDR) strains of tuberculosis?
- Poor compliance
- poor adherence to proper follow-up
- Ineffective RX
How is tuberculosis (TB) spread?
AIROBORNE droplets from an infected person BY:
- Breathing
- Coughing
- Sneezing
- Singing
How long do infectious droplets remain in the air?
Minutes to Hrs
Ways TB is NOT through:
List 4
- touch
- kissing
- utensils
- bed linens
What is the growth environment of Mycobacterium tuberculosis and why does it thrive in the lungs?
- thrives in the lung environment due to its aerobic nature
-requiring oxygen (O2) to survive and multiply.
immunocompetent
funcitoning immune
Can most immunocompetent adults clear M. tuberculosis from their system?
YES!
- In healthy individuals with a functioning immune system, the body can mount an effective immune response against M. tuberculosis, leading to the containment or eradication of the bacteria.
What is the INITIAL defense against M.Tuberculosis for immunocompenten individuals?
trapping bacteria in MUCUS
-which can then be cleared out, preventing infection.
- prevents bacteria from reaching lungs
Does having M.Tuberculosis trapped in the mucus make the person infectious?
No!
person exposed to TB but NOT INFECTED
What happens to M.Tuberculosis if left over bacteria persist after initial defenses
If some bacteria evade initial clearance and persist in the body, the immune system can still contain them but in a** non-replicating dormant state- This is known as latent tuberculosis (latent TB).**
So, is a patient INFECTED during the Latent TB phase?
Yes - patients are infected with M.tuberculosis but will NOT exhibit symptoms and are NOT contagious.
Also, in Latent TB individuals are infected but DO NOT progress to
ACTIVE disease
They are a hallmark of the body’s attempt to contain pathogens that are difficult to eradicate, such as M. tuberculosis.
Granulomas
- organized clusters of immune cells, primarily macrophages, that form in response to chronic inflammation or infection
Granulomas are vital in which phase of TB?
Latent TB
granulomas help prevent
replication and limit the infection
-often resulting in “healed” lesions.
when granulomas are hardened they are considered
healed
What are the TB test results for a patient in the Latent phase?
- Positive for TB
- But infection will NOT progress or further stages
infection
a person is infected
disease
signs of ACTIVE infection and associated health issues
In Immunocompromised individuals, what happens to the granulomas?
Granulomas may form but are ineffective in halting bacterial replication.
If Granulomas fail to contain bacteria, what happens to the bacteria M.TB?
- Leads to reactivation of bacteria.
- Bacteria mutates and progresses from Latent TB to Active TB.
When latent transitions to Active TB, symptoms of the disease may arise
months or years later
Individuals at risk for TB
- Poor/underserved, homeless
- Immigrants, elderly
- IV drug users, alcoholics
- Immunocompromised individuals (HIV, chemotherapy).
- Children under 5 years old.
- Workers in high-risk institutions (prisons, hospitals, shelters).
Clinical Manifestations for Latent TB
KNOW
- No symptoms
- Does not feel sick
(cannot spread TB)
DX results for Latent TB
- (+) TB skin test
- (-) sputum smear
- normal chest x-ray
Active TB/TB disease
Early S/S
- Persistent dry cough leads to productive
-lasts >3 weeks - chest pain (pleuritic)
- low-grade fever
- fatigue
- anorexia
- no appetite/weight loss
- night sweats, chills
Active TB/TB disease
Late S/S
- hemoptysis: coughing up of blood or blood-stained sputum
- dyspnea: SOB
If patients show Active TB S/S, what question should be asked?
Have they traveled recently to:
india (#1), china, indonesia, phillippines, S. Africa
What are the 3 complications associated with TB?
- Cavitations
- Miliary TB
- TB Meningitis
What are Cavitations
Destruction of healthy lung tissue, forming “caves.”
What is Miliary TB?
- Type of meningitis
- spread of TB bacteria throughout the body (in blood), resulting in small lesions (millet seeds) in multiple organs, often leading to systemic symptoms.
Miliary TB:
Acutely ill S/S
- Fever
- dyspnea
- cyanosis
- organ enlargement,
- cognitive changes
- systemic symptoms
(depends on where TB is located)
Miliary TB:
Progression of illness S/S
- Weight loss
- fever
- GI issues
- hepatomegaly
- splenomegaly
- renal changes
- cognitive changes
- severe cough
- dyspnea
What is TB Meningitis
specific form of meningitis resulting from TB infection to the meninges (protective covering of the brain) and spinal cord.
S/S of TB Meningitis
know
- Fever
- persistent HA
- altered mental status
- stiff neck
- dislike bright lights **
- loss of appetite
- vomiting
- seizures
Most important S/S of TB Meningitis
- spread to Meninges leads to seizures - most important **
Complications arrising from TB Meningitis
- long term paralysis
- hearing loss
- blindness
- brain injury
- epilepsy:*unprovoked seizures due to abnormal electricalf activity in the brain
- hydrocephalus: accumulation of cerebrospinal fluid in the ventricles of the brain
- death
5 DX studies for TB
- Tuberculin Skin Test
- Blood Tests
- Chest X-rays
- CT scans
- Sputum Smears and Cultures
Another name used for Tuberculin SKin Test
Mantoux Test
Which of the DX test is the STANDARD for tesing
Tuberculin Skin Test (Mantoux Test)
What is injected into patient when performing Tuberculin Skin Test (Mantoux Test)
0.1 mL of PPD= component of M. Tuberculosis
Is PPD a live bacteria?
NO! NOT A LIVE BACTERIA
What will the skin appear if patient tests positive for Tuberculin Skin Test (Mantoux Test)
Hardening, or induration, of skin at the injection site.
- redness is not enought to read results
How long after a Tuberculin Skin Test (Mantoux Test) does it take to show positive if pt infected with TB?
Will show positive 2-12 weeks AFTER a patient becomes infected with TB.
- can not read results before 2 weeks!!!
If a patient has had a previous POSITIVE skin test, what happens in future TB tests?
Will test positive for life.
Why will an infected TB patient test positive for the rest of their lives when taking a TB skin test?
Body will always continue to make antibodies agains TB
When should TB skin test be administered when it comes to LIVE immunizations?
-
SAME DAY as LIVE virus vaccines
or - 4-6 weeks AFTER administration of live-virus vaccine
What vaccines contain a LIVE-VIRUS?
Know
- varicella
- MMR
- Rota Virus
- small pox
- yellow fever
- ORAL Pollio
- BCG: Bacillus-Calmette-Guerin Vaccine
- NASAL Flu (has to be nasal)
Is COVID a live-virus
NOPE
is an IM flu vaccine live-virus?
NOPE- only nasal flu is live
Is PPD a live-virus
NOPE
BCG recipients is NOT a direct contraindication to TB skin test but may result in
FALSE-POSITIVE test
Can Pregnant patients have the TB skin test (with PPD)?
YEs- safe to administer
Live-virus vaccines NOT safe for
pregnant patients
Why is an adverse reaction to the TB skin test a contraindication for future tests?
- body may react inappropriately to the test substance (tuberculin)
- Administering another skin test in the future could trigger a stronger or dangerous immune response
How would an immunocompromised state possibly affect TB skin test
- Immunocompromised patients are unablel to produce enought antibodies
- will give FALSE NEGATIVE result
- Anything greater than or equal to 5 = positive test
Steps when administering TB skin test
0.1mL of PPD solution (bevel up)
6-10mm in diameter bleb (will absorb quickly)
brief delay b4 withdrawing needle
standard precautions when administering (gloves)
What should you NOT THROW AWAY during a TB skin test?
VIAL!!! - do not throw away until you have documented
Things to know about TB PPD VIAL?
- dark brown in color- light sensitive
- do NOT draw before hand
- once opened good for 30 mins or expiration date- whichever comes FIRST
TB skin test should be read within
48-72 hrs after injection
how to measure induration (hardening or raised)
- Always touch induration
- measure widest diameter
- measure transversely
- record in millimeters (mm)
TB skin test:
Skin that is red and inflammed, should it be included in the** measuring of induration**?
No. only induration (raised/hardening) of skin is measured.
if induration present pt will be monitored for how long
Continue to monitor for 1 week.
in a healthy person with normal immune system, an induration of 15mm is considered
a POSITIVE SKIN TEST.
* a positive reactino is a response by the immune system.
If test is not read between 48-72 hrs what needs to be done?
retake test
Who can read a TB test?
anyone who is trained
Interpretation of results:
≥ 5mm = Positive Test for:
- HIV Infected Individuals
- Immunocompromised (Organ Transplant, Cancer, Chemo, Etc.)
- Pts taking >15 mg/day of PREDNISONE for 1 month or longer
- Pts taking TNF-alpha antagonist
Interpretation of results:
- ≥10mm = Positive Test for:
- Drug users
- Healthcare workers
- Children and Adolescents
Interpretation of results:
- ≥15mm = Positive Test for:
- Persons with NO known risk for TB
- healthy immune patients
Interpretation of results:
No induration:
- Does not guarantee that pt may not have TB
- MANY factors can play a role
When is ‘TWO-STEP testing’ performed
- if suspicion of a possible negative test or to ensure TB dx is not missed
- perfoming 2 skin tests: 1-3 weeks apart.
- **Both test HAVE to be NEGATIVE in order to be considered NEGATIVE. **
2 Types of Blood Test for TB
- IGRA: interferon-gamma release assay
- Quantiferon-TB “Gold Test”
Blood test readings
- Negative results = not infected
- positive results = infected
Why is a further evaluation required for a positive BLOOD test?
to determine if Latent infx or Active dz
Blood tests are not usually done bc
they are expensive
A CXR or CT scans may be done
- AFTER a positive skin test to detect lung abnormalities (infiltrates) in upper lobes of lungs
- Does not confirm or rule out TB
Can CXR define the stage of TB?
Helps define if infection is latent or active but NOT DEFINITIVE.
Which DX test is the MOST CERTAIN to determine stage of TB?
SPUTUM/CULTURE!!!
know
TB Testing:
What does the Sputum Smear test for?
Acid-Fast-Bacilli (AFB)
- type of bacteria, including Mycobacterium tuberculosis, that retain a specific stain (acid-fast stain) under a microscope. This property helps identify TB bacteria in diagnostic tests like AFB smears.
AFB smear DOES NOT confirm dx of TB, but it does indicate
TB disease
* due to some acid-fast-bacilli are not M.tuberculosis
* it’s NOT very sensitive and may not detect the bacteria if they are in low numbers.
How many SPUTUMS test need to be taken to confirm/deny TB?
3 consecutive sputum speciments collected on DIFFERENT days.
What does a positive CULTURE for M.Tuberculosis means?
confirms the definitive diagnoses of TB disease
Culture Tests:
Every sample collected from a patient for TB testing MUST
Must undergo a culture test, even if a preliminary test, like an AFB smear, shows no bacteria, or regardless of AFB smear results.
Down side of Cultures
takes up to 8 weeks
A negative culture test means
patient is in Latent stage of TB
A positive culture test means
patient is in ACTIVE stage of TB
What is the primary treatment for both latent and active TB?
drug Therapy
__ & __ is critical for treatment to be successful
Promoting and monitoring compliance
Hospitalization is reserved for
severly ill patients.
Main class of medications used to treat TB
Anti-Tuberculin - Antibiotics
Many of these Anti-tuberculin (Antbx) drugs can cause
hepatotoxic/hepatitis
- need to monitor liver
What test are needed for baseline of Liver function
AST/ALT
(requirs ongoing monitoring)
S/S of hepatic involvement
- Nausea or vomiting
- loss of appetite
- jaundice
- dark urine
- fever: lasting three or more days and has no obvious cause
Which stage of TB requires MULTIPLE MEDS used in combination
- Active TB
Two types of Anti-Tuberculin Drugs
- First line drugs: need to know 4
- second line drugs: do not need to know
Combination of meds regimen usually lasts
26-39 weeks
(initial phase (plus B6) + continuation phases).
4 main drugs used for Active TB/Disease
- Isoniazid (INH)
- Rifampin
- Pyrazinamide
- ethambutol
What can happen with pt’s who are Non-adherence
List 3
- drug-resistant strains of M.TB.
- danger to public
- increases risk for reactivation of TB.
TB treatment:
What is Directly Observed Therapy (DOT)
ensures patients swallow their anti-tuberculosis medication.
Directly Observed Therapy is used for what patients
Used for ALL TB patients but required for pts who are high-risk for non adherence
Medication that causes peripheral neuropathy
Isoniazid ‘INH’
Isoniazid (INH) is often used for what TB stage?
Latent TB- used by itself.
Causes of Isoniazid
Remember INH
‘INH’:
I- interferes with B6 absorption (Low B6=peripheral neuropathy
N- neuropathy
H-hepatotoxicity - jaundice (yellow skin/sclera, dark urine, fatigue, elevated AST/ALT)
Patients on ISONIAZID should avoid
alcohol- any amount!!!
- if option says ‘reduced alcohol’- DONT CHOOSE IT!!
With Rifampin remember “RED” because
Body fluids turn red/orange: tears, urine, sweat
THis is NORMAL
Pt education when taking Rifampin
- wear glasses (avoid contacts)
- use backup non-hormonal birth control- oral contraceptives wont work
- monitor for jaundice
How to take Rifampin
- take on empty stomach- 1 hr before meals (least effective with food)
- Can make some meds less effective: BB, digoxin, verapamil, anticoags - dont need to know drugs)
Patient education for Pyrazinamide (PZA)
- Sun sensitivity
- jaundice
- dark urine
- bleeding
- difficult urinating (potential liver damage)
- No ALCOHOL
For Etambul Pt education
Think ‘EYE’
- Risk of vision changes (blurry or color changes)- need to report!!!
- routine eye exams recommended.
Drug of choice for Latent TB infection
Isoniazid (INH)
* due to its effectiveness and inexpensiveness
What does Isoniazid (INH) cause?
Liver damag- so NO ALCOHOL
Pts on Isoniazid (INH) usualy take it
1x daily for 6-9 months
(9months= optimal esp for children)
When will Isoniazid (INH) need to be monitored by medical personel?
when dosage is increased
Combination therapy primarily used for
resistant strains or toxicity cases
(ie: isoniazid and rifampin)
What is the treatment duration for Multi-Drug Resistant (MDR) TB?
ADDITION 20-30 months of antbx INJECTIONS
How long after starting TB therapy are most patients no longer infectious?
- After 2-3 weeks of therapy
Why is follow-up with smears, cultures, and chest X-rays essential in TB treatment?
- to confirm recovery
- Tests will be done throughout the course of drug therapy.
Hospitalized clients:
Treatement of Active TB dz will include
- Negative pressure room.
- Airborne Isolation
- Nurse precautions: N95 mask, wash hands before and after caring for patient.
- Patient outside room: pt wears a mask (standard precautions), no mask for healthcare workers needed if pt has a mask.
- Drug Therapy: started ASAP
- CXR, Sputum & Cultures
TB client Education:
- Teach infection control measures: wear masks (1st three weeks), hand-washing, proper disposal of tissues- paper bag or toilet.
- At home: well ventilated, sleep alone, outdoors as much as possible, limit areas of dense population
- Ensure strict adherence to medication regimens: Teach side effects and ways to minimize.
- Reassure patients that after 2-3 weeks of treatment, they are no longer contagious.
- adequate nutrition
- No strict isolation for family members living with infected pt = already exposed.
- No new family or friends can visit until sputum cultures are negative.
Know for test:
do Latent TB pts need PPE when transported?
No- they are not infectious
If pt comes to ER with coughing up blood what should you ask the question immediately?
have they traveled recently?
Questions with Patient and Vitals:
1st thing to do if TB suspected
2nd thing to do
3rd thing to do
4th thing to do
1st: airborne isolation
1nd: O2
3rd: blood cultures BEFORE starting meds
4th: Meds
