Rosen & Barkin's 5-Minute Emergency Medicine Consult (734 page)

• Fever
  
• Tachycardia
  
• Hypoxia
  
• Cachexia
  
• Abnormal breath sounds
  
• Cervical lymphadenopathy
  

• Diagnosis difficult due to the variety of clinical presentations.
  
• Chest radiography:
  
  • Most valuable test for active pulmonary TB
    
• Skin testing: PPD
  

• CBC
  
• Electrolytes, BUN, creatinine, glucose, LFTs
  
• Hyponatremia (due to syndrome of inappropriate antidiuretic hormone)
  
• ABGs for oxygenation/ventilation assessment
  
• Sputum staining for acid-fast bacilli (Ziehl–Neelsen stain):
  
  • Provides a quick presumptive diagnosis
    
• Sputum, CSF, blood, urine, or peritoneal fluid culture:
  
  • Gold standard for diagnosis of TB
    
  • Average time for positive culture is 3–6 wk.
    
  • DNA polymerase chain reaction (PCR) testing more rapid
    
• Lumbar puncture with CSF analysis:
  
  • For suspected TB meningitis
    
  • Elevated WBCs with lymphocyte predominance
    
  • Elevated protein
    
  • Low to normal glucose
    

• Chest radiograph:
  
  • May be normal
    
  • In primary disease, parenchymal infiltrates with unilateral hilar adenopathy are the classic findings.
    
  • Reactivation TB typically appears as cavitary lesions with or without calcification, usually in upper lung segments.
    
  • Miliary TB shows bilateral disseminated 2-mm nodules throughout lungs.
    
  • Chest radiograph may be nondefinitive in AIDS/immunocompromised patients.
    
  • Unilateral pleural effusion in both primary and reactivation TB
    
  • Tracheal deviation with scarring or atelectasis
    
  • Ghon focus—calcified scar/healed primary focus of infection
    
  • Ghon complex—primary infiltrate with associated unilateral hilar adenopathy
    
• Spine radiographs for Potts disease:
  
  • May be normal
    
  • Anterior wedging of 2 involved vertebral bodies and destruction of disk
    
• CT chest:
  
  • Better defines extent of disease
    

Skin testing:

• Inject 0.1 mL of PPD intradermally in the forearm.
  
• Positive test indicates prior or current infection with
  M. tuberculosis.
  
• Test results are read between 48 and 72 hr after administration.
  
• Interpretation of positive: >5-mm induration:
  
  • Close contacts with TB patients
    
  • Positive chest radiographs for TB
    
  • HIV-positive
    
  • Organ transplant or other immunosuppression
    
• >10-mm induration:
  
  • IV drug users
    
  • Immigrants from high-prevalence countries (within 5 yr)
    
  • Underlying disease (diabetes, renal failure, malignancies)
    
  • Healthcare workers
    
  • Prison inmates
    
  • Institutionalized (nursing home, homeless shelters)
    
• >15-mm induration:
  
  • Low-risk individuals
    

• Bacterial pneumonia
  
• Bronchiectasis
  
• Coccidiomycosis
  
• Histoplasmosis
  
• Lung abscess
  
• Lung carcinoma
  
• Lymphoma
  
• Pneumocystis carinii
  pneumonia
  
• Pulmonary embolism
  
• Sarcoidosis
  

TREATMENT

• Place patient in respiratory isolation (negative flow).
  
• Place a mask on the patient to prevent respiratory spread of the disease.
  
• Initiate treatment with an IV, oxygen, and pulse oximetry.
  
• Endotracheal intubation may be required in patients with severe hemoptysis or respiratory compromise.
  
• Providers should wear submicron particulate filter masks (N-95 designation).
  
• Inform close contacts.
  

• ABCs:
  
  • Control airway as needed.
    
  • Administer oxygen as needed.
    
  • Place on patient cardiac monitor and pulse oximetry.
    
  • Establish IV access with 0.9% normal saline
    
• Isolate patients in negative pressure rooms with at least 6 air exchanges per hour.
  
• Protection for healthcare workers (N-95 masks)
  

• Isolation
  and strict respiratory precautions
  
• Treatment is augmented due to increasing multidrug resistance.
  
• Any regimen must contain at least 2 drugs to which the TB bacillus is susceptible.
  
• CDC currently recommends initial therapy that includes 4 1st-line drugs.
  
• LTBI with normal chest x-ray given isoniazid (INH) for 9 mo or weekly combination of INH and rifapentine (RPT) for 12 wk.
  
• Consult infectious disease specialists when treating HIV patients on antiretroviral therapies.
  
• Add dexamethasone for TB meningitis.
  
• Surgical drainage for TB empyema may be necessary; consult thoracic surgeon.
  
• Directly observed therapy (DOT) may be necessary to ensure compliance in certain populations.
  
• Intermittent (biweekly) regimen may demonstrate higher patient compliance.
  

• INH: 5 mg/kg, max. 300 mg (peds: 10–15 mg/kg, max. 300 mg) PO/IM per day:
  
  • Refractory seizures in overdose, treat with pyridoxine 5 g IV over 5 min or PO
    
  • Caution with alcohol coingestion, hepatitis
    
• Rifampin (RIF): 10 mg/kg, max. 600 mg (peds: 10–20 mg/kg, max. 600 mg) PO/IV per day
  
• Pyrazinamide (PZA): 20–25 mg/kg/d max. 2 g (peds: 15–30 mg/kg/d) or:
  
  • <55 kg: 1 g PO per day
    
  • 56–75 kg: 1.5 g PO per day
    
  • >75 kg: 2 g PO per day
    
  • Not recommended in pregnancy
    
• Ethambutol (ETB): 15–20 mg/kg, max. 1,600 mg (peds: 15–30 mg/kg, max. 1 g) PO per day or up to TID
  
  • Not recommended <13 yr old, requires visual testing
    
• RPT: 10 mg/kg, max. 900 mg (peds: Not recommended <12 yr old) PO once per week or 300 mg PO weekly for 10–14 kg, 450 mg PO weekly for 14.1–25 kg, 600 mg PO weekly for 25.1–32 kg, 750 mg PO weekly for 32.1–49.9 kg, 900 mg PO weekly for >50 kg
  
• Rifabutin: 5 mg/kg, max. 300 mg (peds: Unknown) PO per day
  

• Streptomycin: 15 mg/kg/d, max. 1 g (peds: 20–40 mg/kg/d) IM/IV per day:
  
  • Teratogenic: Contraindicated in pregnancy
    
• Ethionamide: 0.5–1 g (peds: 10–20 mg/kg/d) PO div. QID
  
• Levaquin: 750 mg (peds: Contraindicated) PO/IV per day
  

FOLLOW-UP

• Respiratory compromise
  
• Suspicion of diagnosis
  
• Inability to comply with outpatient therapy
  
• Unavailable outpatient resources (no PCP)
  
• Involuntary admission for noncompliant outpatients occurs:
  
  • Be aware of respective state laws concerning involuntary admission (consult infectious disease specialist).
    

• Without respiratory compromise
  
• Home isolation procedure compliance
  
• Ability and willingness to comply with long-term therapy
  
• Appropriate outpatient follow-up and treatment available
  
• Notification of the public health authorities is mandatory.
  

Referral to Department of Public Health for DOT

• Sputum analysis periodically to document clearance
  
• Medication toxicity monitoring:
  
  • INH, RIF, PZA: Monitor liver function tests for hepatitis
    
  • PZA: Check uric acid levels
    
  • ETB: Eye testing for color blindness
    

• Early isolation and respiratory precautions
  
• Careful history to establish risk factors
  
• The chest x-ray and PPD are great diagnostic aids.
  
• Initial 4-drug regimen for active disease
  
• Nonadherent, active TB patients are considered a public health hazard:
  
  • Specific state laws are applicable in numerous areas.
    

• American Thoracic Society; CDC; Infectious Diseases Society of America. Treatment of tuberculosis.
  MMWR Recomm Rep
  . 2003;52(RR-11):1–77.
  
• American Thoracic Society; Centers for Disease Control and Prevention; Infectious Diseases Society of America. American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America: Controlling tuberculosis in the United States.
  Am J Respir Crit Care Med.
  2005;172:1169–1227.
  
• Centers for Disease Control and Prevention (CDC). Recommendations for use of an isoniazid-rifapentine regimen with direct observation to treat latent Mycobacterium tuberculosis infection.
  MMWR.
  2011;60(RR-48):1650–1653.
  
• Moran GJ, Talan DA. Tuberculosis. In: Wolfson AB, ed.
  Harwood-Nuss’ Clinical Practice ofEmergency Medicine.
  5th ed. Philadelphia, PA: Lippincott Williams & Wilkins: 2010:912--917.
  
• Taylor Z, Nolan CM, Blumberg HM. Controlling tuberculosis in the United States. Recommendations from the American Thoracic Society, CDC, and the Infectious Diseases Society of America.
  MMWR Recomm Rep
  . 2005;54(RR-12):1–81.
  http://www.cdc.gov/tb/publications/factsheets/statistics/TBTrends.html
  . Accessed on February 28, 2013.
  

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