Difference between revisions of "Tuberculosis"

(Background)
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[[File:MiliaryTB.png|thumb|Miliary TB neonate born to mother with active TB]]
 
[[File:MiliaryTB.png|thumb|Miliary TB neonate born to mother with active TB]]
 
*>1/3 of world's population is infected
 
*>1/3 of world's population is infected
*Infection Types
+
 
**Primary Infection
+
===Infection Types===
***Usually contained by body via formation of tubercles
+
*Primary Infection
***Hematogenous spread limited to areas w/ high O2 or blood flow (apical lung, vertebrae)
+
**Usually contained by body via formation of tubercles
****PPD positive
+
**Hematogenous spread limited to areas w/ high O2 or blood flow (apical lung, vertebrae)
**Reactivation Infection
+
***PPD positive
***More common in immunocompromised pts (AIDS, malignancy, DM, CRF)
+
*Reactivation Infection
**Check HIV in pts suspected of TB
+
**More common in immunocompromised pts (AIDS, malignancy, DM, CRF)
*Special Populations
+
*Check HIV in pts suspected of TB
**AIDS
+
 
***TB is 200-500x more common in AIDS population than general population
+
===Special Populations===
***CD4 count
+
*[[AIDS]]
****Increased risk when <500
+
**TB is 200-500x more common in AIDS population than general population
****Determines the clinical and radiographic presentations of TB
+
**CD4 count
**Peds
+
***Increased risk when <500
***More likely to progress early to active disease
+
***Determines the clinical and radiographic presentations of TB
****Presentation more commonly that of primary TB
+
*Peds
***>5yr - classic symptoms
+
**More likely to progress early to active disease
***<5yr - miliary TB, meningitis, cervical lymphadenitis, PNA that doesn't respond to abx
+
***Presentation more commonly that of primary TB
***Children are usually not infectious due to their weak cough
+
**>5yr - classic symptoms
 +
**<5yr - miliary TB, meningitis, cervical lymphadenitis, PNA that doesn't respond to abx
 +
**Children are usually not infectious due to their weak cough
  
 
===Clinical Features===
 
===Clinical Features===

Revision as of 10:38, 1 August 2015

Background

Miliary TB neonate born to mother with active TB
  • >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 w/ high O2 or blood flow (apical lung, vertebrae)
      • PPD positive
  • Reactivation Infection
    • More common in immunocompromised pts (AIDS, malignancy, DM, CRF)
  • Check HIV in pts suspected of TB

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
  • Peds
    • More likely to progress early to active disease
      • Presentation more commonly that of primary TB
    • >5yr - classic symptoms
    • <5yr - miliary TB, meningitis, cervical lymphadenitis, PNA that doesn't respond to abx
    • Children are usually not infectious due to their weak cough

Clinical Features

Primary Tuberculosis

  • Usually asymptomatic (only identified by positive PPD)
  • May be rapidly progressive and fatal in immunocompromised pts
    • Fever, malaise, wt 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
    • Lymphadenopathy (painless)
    • Pericarditis
    • Meningitis
    • Adrenal insufficiency
    • Arthritis
    • Osteomyelitis

Differential Diagnosis

HIV associated conditions

Diagnosis

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
  • HIV pts less likely to have classic lesions and may have normal CXR

Treatment

Active TB

  • Isoniazid + rifampin + pyrazinamide + ethambutol x8wk followed by INH/RIF x18wk
    • 2 drug continuation tx x 18-31wk

Latent TB

  • Consider treatment for:
    • Recent conversion to PPD-positive
    • Persons in close contact w/ individual w/ active TB
    • Isoniazid x9mo

Disposition

  • Discharge
    • Otherwise healthy
      • Contact public health services before discharge
        • Instructions for home isolation and f/u 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
    • Pt is noncompliant
  • 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.