Tuberculosis

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

• HIV neurologic complications
  • Toxoplasmosis
  • Cryptococcosis
  • AIDS Dementia
  • Seizures in patients with HIV-AIDS
  • Primary CNS lymphoma
• HIV pulmonary complications
  • Pneumocystis jirovecii pneumonia (PCP)
  • Tuberculosis (TB)
  • CMV pneumonia
• Ophthalmologic complications
  • CMV Retinitis
  • Herpes Zoster Ophthalmicus
• Other
  • AIDS fever of unknown origin
  • Immune reconstitution inflammatory syndrome
  • HIV diarrhea
  • Esophageal candidiasis
  • Kaposi's sarcoma
  • Pruritic papular eruption of HIV
  • Hairy oral leukoplakia
• HAART medication side effects
  • HAART-induced lactic acidosis
  • Neuropyschiatric effects
  • Hepatic toxicity
  • Renal toxicity
  • Steven-Johnson's
  • Cytopenias
  • GI symptoms
  • Endocrine abnormalities

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