Tuberculosis: Difference between revisions

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==Epidemilogy==
==Background==
*Over 1/3 of world's population is infected


===Infection Types===
*Primary Infection
**Usually contained by body via formation of tubercles
**Hematogenous spread limited to areas with high O2 or blood flow (apical lung, vertebrae)
***PPD positive
*Reactivation Infection
**More common in immunocompromised patients (AIDS, malignancy, DM, immunosupressive medications)
*Miliary Tuberculosis
**Disseminated tuberculosis
**Looks like millet seeds
**Seen in patients with comorbid AIDS
***Check [[HIV]] in patients suspected of TB
**PPD is positive in only 50% of cases


- tb resurfaced due to poor public health systems, HIV, and immigration
===Special Populations===
*[[AIDS]]
**TB is 200-500x more common in AIDS population than general population
**CD4 count
***Increased risk when <500
***Determines the clinical and radiographic presentations of TB
*Pediatric
**More likely to progress early to active disease
***Presentation more commonly that of primary TB
**>5yr - classic symptoms
**<5yr - miliary TB, [[meningitis]], [[scrofula|cervical lymphadenitis]], [[pneumonia]] that does not respond to usual antibiotics
**Children are usually not infectious due to their weak cough


- rate of tb now declining due to better public health and decrease xmission of tb from pt with active tb
===Tuberculin Skin Test===
;Used for population screening, but not for rule-out in patients with concern for active disease
''Reaction considered positive in following situations:''
*>5 mm
**[[HIV]] positive
**Close contact with active TB patient
**Nodular or fibrotic changes on CXR
**Immunosuppressed (TNF-alpha inhibitor, chemo, organ transplant)
*>10 mm
**Children < 4 yrs old
**Healthcare/lab/prison employees and residents
**Co-morbid conditions (dialysis, DM, blood/head/neck/lung malignancy, IV drug users)
**People from high prevalence areas
*>15 mm
**Persons with no known risk factors for TB


- many people with latent tb- poses threat if turns active
==Clinical Features==
[[File:Screen Shot 2015-09-11 at 9.27.22 AM.png|thumbnail|Tuberculous lymphadenopathy]]
===Primary Tuberculosis===
*Usually asymptomatic (only identified by positive PPD/quantiferon gold)
*May be rapidly progressive and fatal in immunocompromised patients
**[[Fever]], malaise, weight loss, [[chest pain]]
*Tuberculous [[pleural effusion]] may occur if subpleural node ruptures into the pleura
**Pleuritic [[chest pain]]
**Exudative fluid
***Organisms may not be visible on acid-fast staining (need pleural biopsy)


- globally, 1/3 of world pop infcted
===Reactivation Tuberculosis===
*Pulmonary: Productive [[cough]], [[hemoptysis]], [[dyspnea]], pleuritic [[chest pain]]
*Systemic: [[Fever]], night sweats, malaise, fatigue, weight loss
*Extrapulmonary
**Painless lymphadenopathy/[[scrofula]] (most common extrapulmonary manifestation)
**[[Pericarditis]]
**[[Peritonitis]]
**[[Meningitis]]
**[[Adrenal insufficiency]]
***If adrenals affected, TB typically spreads to bilateral adrenals rather than unilateral
***Think about in the patient presenting in shock with TB risk factors
**[[Arthritis]]
**[[Osteomyelitis]]
***Pott's disease, usually in thoracic spine


==Differential Diagnosis==
{{HIV associated conditions}}


==Consequences==
==Evaluation==
[[File:Miliary.png|thumbnail|CXR of miliary TB]]
[[File:MiliaryTB.png|thumb|Miliary TB neonate born to mother with active TB]]
[[File:Tuberculosis-x-ray-1.jpg|thumbnail|Bilateral pulmonary tuberculosis]]
[[File:Screen Shot 2015-09-11 at 9.21.17 AM.png|thumbnail|Tuberculous vertebral osteomyelitis (Pott's Disease)]]
===[[CXR]]===
*Primary infection
**Infiltrates in any area of the lung
**Isolated hilar or mediastinal adenopathy may be only finding
*Reactivation infection
**cavitary/noncavitary lesions in upper lobe or superior segment of lower lobe
*Latent infection
**Upper lobe or hilar nodules and fibrotic lesions
**Ghon foci, areas of scarring, calcification
*Miliary TB
**Looks like millet seeds on CXR
*Immunocompromised patients less likely to have classic lesions and may have normal CXR


===PCR Sputum Assay===
*Rapidly detects TB in sputum specimens (as well as [[rifampin]] resistance)
*Use to rule-out patients for active TB
*Need two sputum specimens (expectorated or induced) at least 8 hours apart (including at least one early morning specimen)


- xmited by air particles 1-5 microns
==Management==
===Active TB===
*[[Isoniazid]] + [[rifampin]] + [[pyrazinamide]] + [[ethambutol]] x 8wk followed by INH/rifampin x18wk
**2 drug continuation treatment x 18-31wk
**Use of [[pyrazinamide]] in pregnancy is controversial and typically reserved for women with MDR TB<ref>Sokolove PE, Derlet RW: Tuberculosis, in Walls RM, Hockberger RS, Gausche-Hill M, et al (eds): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 9. Philadelphia, Elsevier 2018, (Ch) 127:p 1682-1692.</ref>


- xmission influenced by source criteria- number of bacteria excreted and nature of encounter
===Latent TB===
 
*Isoniazid x 9 months
- infc by 1- 5 bacteria in terminal alveolus
*Consider treatment for:
 
**Recent conversion to PPD-positive
- primary tb usually mild and self limited- often undiagnosed- bacteria seed other organs for subsequent reactivation later
**close contact with active TB
 
**immunocompromised patients (or plan to start immunosuppressive medications)
- 5% of time, infc goes from latent to active dz in 2 yrs
*New vaccine has demonstrated effectiveness (50%) in preventing progression to active TB<ref>Final analysis of a trial of M72/AS01E vaccine to prevent tuberculosis Tait DR, Hatherill M, Van Der Meeren O, et al. N Engl J Med. 2019;381(25):2429-2439.</ref>. However, this is not yet widely available and further research is needed.
 
- most active tb is from latent reactivation buy and also be from infc by second strain of tb- esp if immune compromised or heavy exposure to new bacilli
 
- classic sxs- fvr, sweats, anorexia, wt loss, weakness
 
- organ specific sxs- pulm- cough, CP, hemoptysis
 
primary tb cxr shows infc in mid to lower lungs with lymphadenopathy- reactivation is upper lobe cavitations
 
- signs and sxs more vaied if hiv
 
- lung most common site, but also lymph nodes, pleura, bone, joints. also gu, cns, abd, pericardium
 
 
==Treatment==
 
 
- reportable in all states- even if tx'd in private sector, reporting helps with compliance, tracking contacts, emerging resis patterns, education, outbreaks
 
Anti TB Drugs
 
- 5 first line drugs
 
- second line drugs are less effective or more toxic- only use if pt cannot tolerate first line or resis
 
 
==Adverse Effects==
 
 
INH- hepatitis, neuropathy, cns effects, elevated dilantin lvl, antabuse interaction, give with vit B6
 
Rif- fvr, low platelets, reduces blood levels of other drugs, caused orange urine
 
PZA- hyperuricemia
 
Ethambutol- color discrimination, visual acuity, optic neuritis
 
Strep- auditory and renal dysfnctn
 
 
==Current Recs==
 
 
- always use INH for duration of tx- effective, low cost, tolerable- if not mixed with rifampin- go 18 mo
 
- if double with INH/ rif- 9 mo for cure
 
- if triple with inh/ rif/ pza (pza for first 2 mo) shorten lenght to 6 mo
 
- try 3-4 meds initially and then 2 drugs afterwards
 
- consider local patterns of resis and schedule of administration likely to ensure adherance
 
- direct observation helps ensure compliance
 
- most common regimen- ihn/rif/pza for 8 wks, inh/rif for 16 wks with freq direct observation, and add ethambutol or streptomycin until susceptibility documented
 
- if cx ned, stop p 2 mo of inh/rif
 
- noncompliance not related to race, gender, education....cdc rec direct observation, and rewards
 
- get cxs- helps with resis
 
- baseline lfts, creatinine,cbc
 
- if use pza- check uric acid
 
- if use ethambutol- check vision and red/green color perception
 
- baseline cxr
 
- if cx neg, go by sxs and cxr at 3 mo
 
- sputum cx going from pos to neg - objective tx success- should change in 2 mo
 
- if longer than 3 mo, consider nonadherence, malabsorption, resis
 
- can also test urine for color in rif, urate in pza
 
- cx sputum at end of tx to document cure
 
 
==HIV Pts==
 
 
- hiv pt who adhere to standard tx do not have increased tx failure
 
- tx 6 mo- longer if slow response
 
- protease inhibitors and NNRT inhibitors mixed with rif cause rif toxicity and low levels of PI and NNRTI- avoid by using rifabutin
 
- do not use PI ritonivir or NNRTI delavirdine with rifabutin
 
 
==Extrapulm TB==
 
 
- since fewer bacilli in extrapulm site and good tissue penetration of drugs, tx should be no more difficult
 
- use regular 6 mo regimen
 
- 12 mo for meningitis in kids, bone/ joint or miliary tb
 
 
==Drug Resis==
 
 
- inh resis tx with rif, pza, ethambutol for 6 mo
 
- rif resis- inh, ethm for 18 mo or inh, pza, strep for 9 mo
 
- mulitidrug resis- resis to inh and rif- curable even in poor countries
 
 
==Management of Latent TB==
 
 
- test for tb only in high risk pt and those who will benefit from tx.
 
- if test low risk population- will get too many false postives
 
- test hiv pt, immigrants, homeless, long term care residents, health workers
 
- those at risk for progression from latent to active dz are immune suppressed ore recently exposed to infectious tb- highest rate of progression is from pt with both hiv and tb- also dm, crf, CA, organ xplant, ivda,
 
- silicosis, abnormal cxr, too thin person also indication for testing
 
 
==TB Skin Test==
 
 
- PPD is gold standard for latent tb testing- intradermal not multipronged
 
- measure induration not redness 48- 72 hrs
 
- 5 mm- positve if pt with weak immune response- hiv, steroid use, recent exposure and body hasn't had time to mount immune response, abnormal cxr
 
- 15 mm- positive if low risk pt
 
- 10 mm- all other pts
 
- if long standing infc, may actually have neg test initially- if give second skin test will be positve since first test reinvigorated immune sys- so if pt needs serial testing- do second test in 2 wks- called 2 Step Testing- if second postive represents long standing infc not recent infection
 
- ppd will not cause 10 mm induration in uninfected pt ever
 
 
==BCG==
 
 
- not recommended in US but used elsewhere
 
- size and persistence of tb reaction p bcg vary with bcg dose and manufacturer
 
- CDC rec ignoring hx of bcg when giving and interpreting ppd test since bcg only givien in high risk populations in first place
 
- anergy testing not recommended in tb testing of hiv pt since results highly variable and not reproducible.
 
 
==Latent Tx/ PPD + Tx==
 
 
- 9 mo inh if no hiv and neg cxr. 12 mo better but less compliance and more cost
 
- 9 mo ihn if hiv + or pos cxr or age <18yr
 
- can also do 2 mo of rif and pza or 4 mo of rif alone
 
- baseline labs if hiv +, preg, etoh, liver dz
 
- if duration of tx interrupted, add on additional 3 mo of inh. If lapse is greater than 3 mo, restart whole tx
 
- if previously tx pt reexposed to tb, repeat tx not recommended


==Disposition==
===Discharge===
*Otherwise healthy
**Contact public health services before discharge
***Instructions for home isolation and follow up at appropriate clinic to receive meds
**Do not start TB meds in ED unless specifically instructed by public health


===Admit===
*Ill-appearing
*Diagnosis is uncertain
*Patient is treatment non-adherent


==External Links==
*https://www.cdc.gov/tb/default.htm


==References==
<references/>
[[Category:ID]]
[[Category:ID]]
[[Category:Pulmonary]]

Latest revision as of 18:45, 14 December 2022

Background

  • Over 1/3 of world's population is infected

Infection Types

  • Primary Infection
    • Usually contained by body via formation of tubercles
    • Hematogenous spread limited to areas with high O2 or blood flow (apical lung, vertebrae)
      • PPD positive
  • Reactivation Infection
    • More common in immunocompromised patients (AIDS, malignancy, DM, immunosupressive medications)
  • Miliary Tuberculosis
    • Disseminated tuberculosis
    • Looks like millet seeds
    • Seen in patients with comorbid AIDS
      • Check HIV in patients suspected of TB
    • PPD is positive in only 50% of cases

Special Populations

  • AIDS
    • TB is 200-500x more common in AIDS population than general population
    • CD4 count
      • Increased risk when <500
      • Determines the clinical and radiographic presentations of TB
  • Pediatric
    • More likely to progress early to active disease
      • Presentation more commonly that of primary TB
    • >5yr - classic symptoms
    • <5yr - miliary TB, meningitis, cervical lymphadenitis, pneumonia that does not respond to usual antibiotics
    • Children are usually not infectious due to their weak cough

Tuberculin Skin Test

Used for population screening, but not for rule-out in patients with concern for active disease

Reaction considered positive in following situations:

  • >5 mm
    • HIV positive
    • Close contact with active TB patient
    • Nodular or fibrotic changes on CXR
    • Immunosuppressed (TNF-alpha inhibitor, chemo, organ transplant)
  • >10 mm
    • Children < 4 yrs old
    • Healthcare/lab/prison employees and residents
    • Co-morbid conditions (dialysis, DM, blood/head/neck/lung malignancy, IV drug users)
    • People from high prevalence areas
  • >15 mm
    • Persons with no known risk factors for TB

Clinical Features

Tuberculous lymphadenopathy

Primary Tuberculosis

  • Usually asymptomatic (only identified by positive PPD/quantiferon gold)
  • May be rapidly progressive and fatal in immunocompromised patients
  • Tuberculous pleural effusion may occur if subpleural node ruptures into the pleura
    • Pleuritic chest pain
    • Exudative fluid
      • Organisms may not be visible on acid-fast staining (need pleural biopsy)

Reactivation Tuberculosis

Differential Diagnosis

HIV associated conditions

Evaluation

CXR of miliary TB
Miliary TB neonate born to mother with active TB
Bilateral pulmonary tuberculosis
Tuberculous vertebral osteomyelitis (Pott's Disease)

CXR

  • Primary infection
    • Infiltrates in any area of the lung
    • Isolated hilar or mediastinal adenopathy may be only finding
  • Reactivation infection
    • cavitary/noncavitary lesions in upper lobe or superior segment of lower lobe
  • Latent infection
    • Upper lobe or hilar nodules and fibrotic lesions
    • Ghon foci, areas of scarring, calcification
  • Miliary TB
    • Looks like millet seeds on CXR
  • Immunocompromised patients less likely to have classic lesions and may have normal CXR

PCR Sputum Assay

  • Rapidly detects TB in sputum specimens (as well as rifampin resistance)
  • Use to rule-out patients for active TB
  • Need two sputum specimens (expectorated or induced) at least 8 hours apart (including at least one early morning specimen)

Management

Active TB

Latent TB

  • Isoniazid x 9 months
  • Consider treatment for:
    • Recent conversion to PPD-positive
    • close contact with active TB
    • immunocompromised patients (or plan to start immunosuppressive medications)
  • New vaccine has demonstrated effectiveness (50%) in preventing progression to active TB[3]. However, this is not yet widely available and further research is needed.

Disposition

Discharge

  • Otherwise healthy
    • Contact public health services before discharge
      • Instructions for home isolation and follow up at appropriate clinic to receive meds
    • Do not start TB meds in ED unless specifically instructed by public health

Admit

  • Ill-appearing
  • Diagnosis is uncertain
  • Patient is treatment non-adherent

External Links

References

  1. ↑ Gutteridge, David L MD, MPH, Egan, Daniel J. MD. The HIV-Infected Adult Patient in The Emergency Department: The Changing Landscape of the Disease. Emergency Medicine Practice: An Evidence-Based Approach to Emergency Medicine. Vol 18, Num 2. Feb 2016.
  2. ↑ Sokolove PE, Derlet RW: Tuberculosis, in Walls RM, Hockberger RS, Gausche-Hill M, et al (eds): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 9. Philadelphia, Elsevier 2018, (Ch) 127:p 1682-1692.
  3. ↑ Final analysis of a trial of M72/AS01E vaccine to prevent tuberculosis Tait DR, Hatherill M, Van Der Meeren O, et al. N Engl J Med. 2019;381(25):2429-2439.
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