Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Clin Med II Unit II > 7 TB Histo Cocci > Flashcards

7 TB Histo Cocci Flashcards

1
Q

Number one killer of HIV+ patients

A

TB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

TB is transmitted through …

A

Airborne droplet nuclei

Expelled with coughing, sneezing, shouting, singing

Transmission occurs when inhaled nuclei reach alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Can a drunk hobo give you TB by coughing on you as you walk past?

A

No - usually requires prolonged exposure - someone you live with or residents of prisons, nursing homes, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

95% of TB infections are…

A

Latent

TB bacteria present in the body without symptoms

Macrophages ingest tubercle bacilli creating barrier shell called a granulomatous - can see on CXR

Unable to transmit infection to others

Latent TB may activate to disease state if pt becomes immunocompromised and granulomas break open

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

____% initially develop TB disease within 2 years after infection and another ____% develop from latency later (reactivation TB)

A

5% and 5% - for a total of 10% exposed healthy individuals have lifetime risk of getting active TB

TB only becomes active if immune system unable to fight infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Without treatment, the risk of developing TB disease once infected is ________ for people with HIV

A

100x higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Without treatment, the risk of developing TB disease once infected is ______ for diabetics

A

3X higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Main TB risk factors

A

Immunocompromised (HIV, kids<5, DM, Silicosis, malnutrition, substance abuse, immunosuppressive therapy)

Immigrants from areas with high TB prevalence

Injection Drug Users

Close living quarters (nursing homes, institutions, correctional facilities, hospitals)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Main Sx of TB

A

Fever
Cough (3+ weeks, +/- productive, +/- hemoptysis)
CP (pleuritic or retrosternal)

Other Sx: weakness, weight loss, anorexia, chills, night sweats, dyspnea

Extrapulmonary TB disease Sx depends on location

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Classic physical exam finding for TB

A

POSTTUSSIVE CRACKLES

PE may be normal

May also have dullness or decreased fremitius if pleural thickening

LAD

Clubbing if more severe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is the Mantoux TST given?

A

Intradermal injection, create wheal with 0.1 ml Purified Protein Derivative

Read in 48-72 hours and measure INDURATION, not redness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

5 mm is a positive TST response in ..

A 
HIV+ persons
Recent contacts of those with active TB
Persons with evidence of TB on CXR
Immunosuppressed patients (ie chronic steroids)
Organ transplant patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

10 mm is a positive TST in …

A

Recent immigrants from countries with high rates of TB infection
HIV negative IVDUs
Mycobacteriology lab personnel
Residents/employees of high risk congregate settings
Persons with certain high risk medical conditions
Children <4
Children and adolescents exposed to high risk adults

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Positive TST result in anyone without risk factors for TB

A

15 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

2 step TST is recommended as initial test for …

A

Health care workers and individuals requiring periodic testing

1st negative, repeat in 1-3 weeks

2nd positive, TB infection present (creates boosted response and is likely due to past exposure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What might cause a false positive on TST?

A

BCG (bacillus Calmette-Guerin) vaccine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Test that measures immune response in blood to TB

A

IGRA: Quantiferon-TB Gold and T-SPOT TB

Blood incubated with TB antigen and response measured

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When might you use QuantiFeron-TB Gold instead of TST?

A

Concerns of patient not returning for reading

Patients who received BCG vaccination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why don’t we just use the Quantiferon-TB gold test for everyone?

A

Expensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

CXR findings in Primary active TB

A

Initial: Hilar LAD or normal

May progress with pleural effusions and/or infiltrates

Cavities seen with progressive pulmonary TB

May also see miliary pattern

CXR helpful but cannot determine active vs inactive disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why is calcification a good thing when reviewing CXR of suspected TB patient?

A

Dense nodules or lesions indicate latent disease, less likely to reactivate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Signs of reactivation of TB on CXR

A

Cavities, infiltrates, and possible LAD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

CXR abnormalities usually appear in ….

A

Apical/posterior upper lobes (80-90%) or superior areas of lower lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the Ranke Complex?

A

Indicates healed primary pulmonary TB

Ghon lesion (Focus): calcified parenchymal granulomatous (tuberculoma)

Ipsilateral calcified hilar lymph nodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How do you do sputum collection for TB Dx?

A

3 specimens, at least 8-24 hours apart

At least one first thing in the morning

26
Q

What are the three methods for analyzing sputum in possible TB cases?

A
  1. Smear (acid fast bacilli - AFB) - quick and easy, supports Dx but not confirmatory
  2. Cytology (nuclei acid amplification - NAA) takes 48 hours, supports Dx but does not confirm
  3. Culture - GOLD STANDARD; confirms Dx but takes weeks

If Smear and Cytology positive, begin Tx while waiting for Culture

27
Q

Once TB culture is positive, what do you do?

A

Drug susceptibility testing

28
Q

If culture is negative and TB disease still suspected, what do you do?

A

Treat anyway and monitor response to treatment

29
Q

If you do a biopsy for TB, what will you see?

A

Necrotizing (caseating) granulomas

30
Q

What are these new fangled Xpert MTB/RIF Assays?

A

Automated NAA test using disposable cartridges - can ID M tuberculosis DNA and rifampin resistance

Takes only 2 hours and requires minimal training but its expensive and doesn’t replace AFB smear or culture

31
Q

Treatment of Active TB

A

Isolated, negative pressure inpatient hospital room

Direct Observed Therapy (DOT)

“RIPE” drugs
Rifampin
Isoniazid
Pyrazinamide
Ethambutol
32
Q

Rifampin side effects

A

Excreted as red-orange compound in tears, sweat, urine

Skin sensitivity

33
Q

Isoniazid side effects

A

Hepatotoxicity (monitor LFTs)
Peripheral Neuropathy: Vitamin B6 may be given
Fatal hepatitis (pregnant women at increased risk)

34
Q

Pyrazinamide side effects

A

Hepatotoxicity

Hyperuricemia

35
Q

Ethambutol side effects

A

Optic neuritis: test visual acuity and color vision

36
Q

How are the RIPE drugs administered?

A

Initial (intensive) phase: 4 meds daily x 2 months (DOT)

Repeat CXR, AFB smear, and culture

Continuation phase: RIF and INH daily or twice weekly x 4 months (may be extended based on sputum culture and med tolerance

37
Q

Treatment considerations for special cases

A

HIV: extends treatment 9-12 months (intermittent dosing)

Pregnant women: No PZA given

Infants/children: EMB not given and may extend treatment

38
Q

Criteria to not be considered infectious for TB

A

2 weeks of treatment
3 negative sputum smears
Symptoms improve

39
Q

Who can go home while still infectious?

A

Those who can strictly follow up and have DOT arranged

No children < 5 or immunocompromised individuals in home

Unable to travel except to healthcare visits

40
Q

How is latent TB treated?

A

9 month regiment of Isoniazid 300mg daily or 900mg twice weekly using DOT (this is preferred therapy for pregnant women and children 2-11 - but monitor LFTs)

New preferred regime for adults and children ≥ 12: Combined INH and Rifapentine for 12 weekly doses (NOT used in pregnancy)

41
Q

How is MDR-TB defined?

A

Does not respond to at least INH and RIF

Causes: inadequate meds or dosing, premature treatment interruption, spontaneous genetic mutation

42
Q

How is XDR-TB defined

A

Extensively drug resistant TB, responds to even fewer drugs including fluoroquinolone

Surgery to remove necrotic tissue important but often not available

43
Q

What is the purpose of the BCG vaccine

A

To decrease risk of severe consequences due to TB

Does not prevent primary infection or activation of latent TB

Proven to protect against meningitis and disseminated TB in kids though

Given as single dose at birth in developing countries

44
Q

Fungal infection associated with soil contaminated with bird or bat droppings

A

Histoplasmosis

Occurs most frequently in OH and Mississippi River valleys (midwestern states)

Most common among individuals with HIV/AIDs or other weakened immune systems

45
Q

Clinical presentation of histoplasmosis

A

Hx of SPELUNKING, construction, demolition, mining, roofing, farming, gardening, installing AC units

Incubation period is 3-17 days after exposure

90% asymptomatic or mild flu-like symptoms

Most symptoms resolve in few weeks to a month unless infection becomes more severe

46
Q

50-90% of pt with histoplasmosis are …

A

Asymptomatic

CXR may show residual granuloma

47
Q

What is acute symptomatic pulmonary histoplasmosis?

A

Fever and marked fatigue, few respiratory symptoms

Symptoms extend from 1 week to 6 months

Mild Sx are typically self-limited

48
Q

Progressive disseminated histoplasmosis occurs in …

A

Immunocompromised patients

Fever, marked fatigue, cough, dyspnea, weight loss

Multiple organ involvement

Fatal within 6 weeks

49
Q

Chronic pulmonary histoplasmosis occurs in…

A

Older COPD patients and those with progressive lung changes (apical cavities)

50
Q

Dx of histoplasmosis is usually via…

A

Serology

Antibody tests (Immunodiffusion (ID) and Complete Fixation (CF) tests

Antigen detection via enzyme immunoassay (EIA test) - can be either urine or serum testing

51
Q

CXR findings for histoplasmosis

A

Hilar adenopathy

Patchy or nodular infiltrates in lower lobes

52
Q

Treatment for histoplasmosis

A

Acute mild to moderate - no treatment

Others - either an azole or Ampho B if pregnant

53
Q

Fungal infection endemic to lower deserts of Western Hemisphere

A

Coccidioidomycosis (Valley Fever)

Inhalation of spores from contaminated soil - outbreaks occur following dust storms and earthquakes

54
Q

Clinical presentation of Cocci

A

Lives or recently traveled to SW

Activities increasing exposure: excavation, construction, playing in the dirt (dogs can get it too)

Incubation 1-3 weeks

60% asymptomatic

More severe presentation in immunocompromised, pregnant women, DM, African and Filipinos

55
Q

Sub-acute valley fever

A

Mild respiratory Sx that are self-limited and last weeks to months - may be considered protective from future disease

56
Q

Symptoms of primary Cocci infection

A

Typically present with community acquired pneumonia 7-21 days following exposure

Primary Sx: Fever, cough, pleuritic CP

Others: Marked fatigue, HA, arthralgia, erythema multiform, erythema nodosum

57
Q

Sx of disseminated disease in Cocci patients

A

Has spread to Lungs Bones or Brain

Higher Risk: HIV, African or Filipino descent, 3rd trimester of pregnancy

More pronounced lung findings (ie abscess)

Bone lesions

Lymphadenitis, meningitis

58
Q

Lab findings in Cocci

A

Eosinophils with slight leukocytosis

59
Q

CXR findings vary in cocci but include…

A

Hilar LAD

Patchy, nodular pulmonary infiltrates

Miliary infiltrates

Thin wall cavities

60
Q

Treatment of cocci not generally required but for patients who are high risk or have severe illness…

A

Symptomatic therapy = -azole

Ampho B if severe or pregnant

Prognosis = good with limited disease, but 50% mortality if disseminated

61
Q

Think cocci when …

A

Pulmonary complaints and one or more of the 3 Es:

Erythema nodosum
Erythema multiforme
Eosinophilia

Clin Med II Unit II (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions