Brainscape's Knowledge GenomeTM

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


See full index

MBBS 3: Pediatrics > Tuberculosis in Children > Flashcards

Tuberculosis in Children Flashcards

1
Q

Clinical stages of TB?

A
  1. tuberculosis exposure
  2. tuberculosis infection
  3. tuberculosis disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Tuberculosis exposure?

A
  1. Tuberculin skin test (TST)orinterferon-γ release assay (IGRA)negative
  2. Normal CXR, physical examination; no signs/symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tuberculosis infection?

A
  1. Positive TST or IGRA result
  2. No signs or symptoms, normal physical examination, CXR either normal or has granuloma or calcifications
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Tuberculosis disease?

A

Positive signs/symptoms/radiographic manifestations

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

Progression of infection to disease?

A
  1. primary infection progressively destructive
  2. liquefaction of the lung parenchyma
  3. formation of a thin-walled primary tuberculosis cavity
  4. bullous tuberculosis lesions
  5. rupture of the lesions
  6. pneumothorax
  7. erosion of a parenchymal focus of tuberculosis into a blood or lymphatic vessel
  8. Dissemination of the bacilli and amiliary pattern (small nodules evenly distributed on the chest radiograph)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Clinical features of tuberculosis?

A

Nonproductive cough and mild dyspnea - most common symptoms
Systemic complaints: fever, night sweats, anorexia, and decreased activity - less often
Difficulty gaining weight / true failure-to-thrive
Pulmonary signs - less common
Localised wheezing or decreased breath sounds - Bronchial

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

Which age group experiences signs and symptoms the most?

A

infants
Note: most children with TB have pulmonary TB

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

Approach to diagnosis of TB in children?

A

Careful history (history of TB contact and symptoms of TB)
Clinical examination (including growth assessment)
Tuberculin skin testing (if available)
Chest X-ray (if available)
Bacteriological confirmation whenever possible
Investigations relevant for suspected pulmonary TB and suspected extra-pulmonary TB
HIV testing

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

What important to note about testing for TB?

A
  • A trial of treatment with anti-TB medications is not recommended as a method of diagnosing TB in children.
  • A negative Xpert MTB/RIF result does not exclude TB in children and a clinical decision should be made in all such cases.
  • Exclusion of co-infection with HIV also has important implications because it often makes the clinical diagnosis of TB more straightforward.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Key risk factors for TB in children?

A

Household or other close contact with a case of pulmonary TB (especially smear-positive or culture-positive pulmonary TB)
Age less than 5 years
HIV infection
Severe malnutrition

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

Physical signs highly suggestive of extra-pulmonary TB?

A
  1. Gibbus, especially of recent onset (resulting from vertebral TB)
  2. Non-painful enlarged cervical lymphadenopathy, +/- fistula formation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is gibbus?

A

characterized byanterior collapse of one or more vertebral bodies resulting in kyphosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Physical signs requiring investigation to exclude extrapulmonary TB?

A
  1. Meningitis not responding to antibiotic treatment, with a subacute onset and/or raised intracranial pressure
  2. Pleural effusion
  3. Pericardial effusion
  4. Distended abdomen with ascites
  5. Non-painful enlarged joints
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the Mantoux tuberculin skin test?

A

consists of intradermal injection of tuberculin material which stimulates a delayed-type hypersensitivity response mediated by T lymphocytes and in patients with prior mycobacterial exposure
- causes induration at the injection site within 48 to 72 hours

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

Function of the tuberculin skin test?

A
  • A positive TST indicates infection with MTB
  • It does not indicate TB disease
  • It measures immune response not the presence/absence of bacteria
  • Can be used to assess children with suspected TB (esp. when there is negative TB contact)
  • Can also be used to screen children exposed to TB
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do you perform the Mantoux tuberculin test?

A

injecting 0.1mL of liquid containing 5 TU (tuberculin units) PPD (purified protein derivative) into the top layers of skin of the forearm
- doctors should read skin tests 48-72 hours after injection

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

How do you know if TST is positive?

A

if a palpable induration is >10 mm or more in diameter irrespective of whether or not had BCG immunization
Note: only induration should be measured, not the surrounding erythema

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

TST and BCG vaccine?

A

because purified protein derivative of tuberculin is a mixture of proteins, some of which are expressed both by Mycobacterium Tuberculosis and BCG
- so the TST could be positive because of BCG vaccination

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

A TST should be regarded as positive in which situations?

A
  1. In immunosuppressed (HIV-positive children, severely malnourished children, [marasmus or kwashiorkor]): >5 mm diameter of induration
  2. In all other children (whether immunized with BCG or not): >10 mm diameter of induration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the specimens for microscopy and culture used for bacteriological confirmation?

A
  1. Sputum (expectorated or induced)
    - Respiratory secretions in children are continually being swallowed and therefore can be sampled from the stomach using a nasogastric tube
  2. Gastric aspirates
  3. Other specimens - depending on the site (e.g. lymph node biopsy)
  4. Fine-needle aspiration of enlarged lymph glands (for staining of acid-fast bacilli (AFB), culture and histology)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Specimen collection in adolescents?

A

TB in older children and adolescents is often similar to adult-type disease (and so is not paucibacillary)
- In this age group, sputum is often readily available and is often AFB-positive
Note: There are problems with performing induced sputum safely and protecting others from infectious aerosols and it is not a procedure which can be performed in young children

23
Q

Advantages of culture in MTB?

A
  1. TB in young children is usually a paucibacillary disease
    - meaning that culture is much more likely than microscopy to yield a positive diagnosis
    - skin smear negative and show no evidence of more advanaced disease on biopsy
  2. Differentiates M. tuberculosis from non-tuberculous mycobacteria
  3. Allows drug susceptibility testing
24
Q

Indications for bacteriological confirmation?

A
  1. Suspected drug-resistant TB
  2. HIV infection
  3. Complicated or severe cases of TB disease
  4. An uncertain diagnosis
  5. Been previously treated
25
Q

What is the Xpert MTB/RIF test?

A
  • It is performed in a single, enclosed, plastic cartridge
  • It is a DNA PCR technology
  • Detects bothM. tuberculosisand the presence or absence of the genetic mutations for rifampicin resistance
  • Xpert MTB/RIF has equivalent sensitivity to culture, but within 2 hours
  • Does not mandate special biosafety precautions (safer than ZN stain and culture)
26
Q

Children living with HIV infection have increased risk of?

A
  1. TB exposure
  2. TB Infection
  3. Progression to TB disease
  4. TB-related morbidity and mortality
    - This risk is influenced by the degree of immune suppression
27
Q

When should Screening for TB in HIV take place?

A

All children living with HIV infection in a TB-endemic setting should therefore be regularly screened for TB by clinical assessment at each visit to a health facility or contact with a health worker
Note: Pulmonary TB a defining condition for HIV AIDS.

28
Q

Challenges in Diagnosis TB in HIV Positive Children?

A
  1. Clinical features of pulmonary TB are similar to HIV-related diseases and therefore lack specificity for a diagnosis of TB
  2. Most children living with HIV are by the mother - Therefore The peak age of HIV infection is in infants and young children; age at which confirmation of acute/chronic lung disease (including TB) is difficult
  3. TST is less sensitive in HIV patients; induration of >5 mm is considered positive
  4. High incidence of acute/chronic lung diseases other than TB
  5. Co-infection; Can mask response to therapy
  6. Overlap of radiographic findings in TB and other HIV-related lung disease
29
Q

How do you prevent TB?

A

If TB is excluded during screening, IPT should be offered to
1. HIV-negative children aged less than 5 years
2. HIV-positive contacts of any age
Note: Patients with HIV infection have a 10% risk of reactivation each year

30
Q

Investigations for suspected pulmonary TB?
What is seen?

A

Chest radiography
1. the commonest picture is persistent opacification in the lung together with enlarged hilar or subcarinal lymph glands.
2. A miliary pattern of opacification in HIV-negative children is highly suggestive of TB

31
Q

Describe the radiographic changes of an adolescent positive TB patient?

A
  1. large pleural effusions and apical infiltrates with cavity formation being the most common forms of presentation.
  2. may also develop primary disease with hilar adenopathy and collapse lesions.
    Note: similar to that of adults
32
Q

What are the types of extra-pulmonary TB in children?

A
  1. peripheral lymphadenopathy - esp. cervical
  2. miliary TB - e.g. disseminated
  3. tuberculous meningitis
  4. pleural effusion (older children and adolescents
  5. abdominal TB - e.g. peritoneal
  6. osteoarticular
  7. pericardial TB
33
Q

Diagnosis of peripheral lymphadenopathy?

A

Lymph node biopsy or fine needle aspiration

34
Q

Diagnosis of miliary TB?

A

Chest radiograph and lumbar puncture (to test for meningitis)

35
Q

Diagnosis of tuberculous meningitis?

A

Lumbar puncture (and imaging where available and indicated)

36
Q

Diagnosis of pleural effusion?

A
  1. Chest radiograph
  2. pleural tap for biochemical analysis (protein and glucose concentrations)
  3. cell count and culture
37
Q

Diagnosis of abdominal TB?

A

Abdominal ultrasound and ascitic tap

38
Q

Diagnosis of osteoarticular TB?

A

Radiograph of joint/bone, joint tap or synovial biopsy

39
Q

Diagnosis of pericardial TB?

A

Ultrasound and pericardial tap

40
Q

The main objectives of anti-TB treatment are to?

A
  1. Cure the patient of TB
  2. Prevent death from TB disease or its late effects
  3. Prevent relapse of TB
  4. prevent the development and transmission of drug-resistant TB
  5. Reduce transmission of TB to others
  6. Achieve all this with minimal toxicity
41
Q

Treatment?

A
  1. isoniazid (H)
    - 10 mg/kg (range 10 – 15 mg/kg); max. dose 300 mg/day
  2. rifampicin (R)
    - 15 mg/kg (range 10 – 20 mg/kg); max. dose 600 mg/day
  3. pyrazinamide (Z)
    - 35 mg/kg (range 30 – 40 mg/kg)
  4. ethambutol (E)
    - 20 mg/kg (range 15 – 25 mg/kg)
42
Q

Importance of monitoring a childs weight at the TB clinic?

A

It is important to monitor the child’s weight at every clinic visit and to adjust drug doses accordingly
- Many children rapidly gain weight after initiation of TB treatment

43
Q

Treatment regimen for Tb meningitis, miliary TB and osseous/bone TB?

A
  1. HRZE - 2 months
  2. HR - 10 months
    - total length of treatment is 12 months
44
Q

Treatment regimen for pulmonary TB, TB lymphadenitis and all other forms of TB?

A
  1. HRZE - 2 months
  2. HR treatment - 4 months
    - total length of treatment = 6 months
45
Q

Corticosteroid management?

A

indications
1. Tuberculous meningitis
2. Complications of airway obstruction by TB lymph glands
3. Pericardial TB

46
Q

Why are corticosteroids used in TB?

A
  • In TB meningitis and pericardial effusion, steroids have a supportive therapeutic effect
  • Steroids have been shown to improve survival in patients with TB meningitis and decrease the risk of developing constrictive pericarditis in patients with pericardial effusions
47
Q

Pyrodoxine management?

A

indicated in all children particularly
1. HIV-positive
2. Malnourished children

48
Q

Why do we use pyrodoxine in TB?

A

Pyridoxine (vitamin B6) protects against isoniazid-induced peripheral neuropathy
- Pyridoxine is recommended for all children on TB treatment and IPT

49
Q

Nutritional support in TB?

A
  1. To lactating mother of infants with TB
  2. To all children with TB
50
Q

Prevention of TB?

A
  1. Neonatal BCG vaccination
  2. Prevention of Mother to child Transmission of HIV (PMTCT)
  3. TB screening in all HIV positive children
  4. All children with TB and their families should be tested for HIV
  5. Screen all children in contact with infectious TB cases
51
Q

What does BCG protect you from?

A

Neonatal BCG vaccination provides substantial protection against the more severe types of disseminated TB, such as miliary TB and tuberculous meningitis, to which infants and young children are particularly susceptible.
Note: BCG vaccine should not be used in children who are known to be HIV-positive because of the increased risk of severe and often fatal disseminated BCG disease

52
Q

In HIV positive infants, BCG can cause the following?

A
  1. Fatal disseminated BCG disease
  2. BCG-induced immune reconstitution inflammatory syndrome (BCG-IRIS)
53
Q

What is BCG?

A

Bacille Calmette-Guérin (BCG) is a live attenuated vaccine derived from Mycobacterium bovis

54
Q
A

MBBS 3: Pediatrics (40 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions