Difference between revisions of "Tuberculosis"

(Created page with "==Epidemilogy== - tb resurfaced due to poor public health systems, HIV, and immigration - rate of tb now declining due to better public health and decrease xmission of tb from...")
 
(Reactivation Tuberculosis)
(45 intermediate revisions by 9 users not shown)
Line 1: Line 1:
==Epidemilogy==
+
==Background==
 +
[[File:MiliaryTB.png|thumb|Miliary TB neonate born to mother with active TB]]
 +
*Over 1/3 of world's population is infected[[File:Tuberculosis-x-ray-1.jpg|thumbnail|Bilateral pulmonary tuberculosis]]
  
 +
===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 - milliary TB, meningitis, 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==
 +
===Primary Tuberculosis===
 +
*Usually asymptomatic (only identified by positive PPD/quantiferon gold)[[File:Screen Shot 2015-09-11 at 9.27.22 AM.png|thumbnail|Tuberculous lymphadenopathy]][[File:Screen Shot 2015-09-11 at 9.21.17 AM.png|thumbnail|Tuberculous vertebral osteomyelitis (Pott's Disease)]]
 +
*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, wt 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 spione
  
+
==Differential Diagnosis==
 +
{{HIV associated conditions}}
  
==Consequences==
+
==Evaluation==
 +
===CXR===
 +
[[File:Miliary.png|thumbnail|CXR of miliary TB]]
 +
*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===
- xmission influenced by source criteria- number of bacteria excreted and nature of encounter
+
*[[Isoniazid]] + [[rifampin]] + [[pyrazinamide]] + [[ethambutol]] x 8wk followed by INH/rifampin x18wk
 
+
**2 drug continuation treatment x 18-31wk
- infc by 1- 5 bacteria in terminal alveolus
+
===Latent TB===
 
+
*Isoniazid x 9 months
- primary tb usually mild and self limited- often undiagnosed- bacteria seed other organs for subsequent reactivation later
+
*Consider treatment for:
 
+
**Recent conversion to PPD-positive
- 5% of time, infc goes from latent to active dz in 2 yrs
+
**close contact with active TB
 
+
**immunocompromised patients (or plan to start immunosupressive medications)
- 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
  
 +
==References==
 +
<references/>
 
[[Category:ID]]
 
[[Category:ID]]
 +
[[Category:Pulmonary]]

Revision as of 19:53, 30 September 2018

Background

Miliary TB neonate born to mother with active TB
  • Over 1/3 of world's population is infected
    Bilateral pulmonary tuberculosis

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 - milliary 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

Primary Tuberculosis

  • Usually asymptomatic (only identified by positive PPD/quantiferon gold)
    Tuberculous lymphadenopathy
    Tuberculous vertebral osteomyelitis (Pott's Disease)
  • 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)

Reactivation Tuberculosis

  • Pulmonary: Productive cough, hemoptysis, dyspnea, pleuritic chest pain
  • Systemic: Fever, night sweats, malaise, fatigue, wt 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 spione

Differential Diagnosis

HIV associated conditions

Evaluation

CXR

CXR of miliary TB
  • 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 immunosupressive medications)

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

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.