5-96
by droplet inhalation. The incubation period is 1-7 days. This rare disease has foci in the western USA, South
America, Asia and Africa. The bubonic form (90-95% of cases) has a very rapid onset associated with a
toxic state characterized by enlarged and very tender lymph nodes (buboes). The other forms of plague,
pneumonic (progression of 5% of bubonic cases) and septicemic (5-10% of cases) are rapidly toxic and nearly
always fatal if untreated.
Subjective: Symptoms
Constitutional: Acute (< 2 hr): Sudden onset fever, chills, headache, myalgias, lethargy
Specific: Sub-acute (24-48 hr): Cough, if pneumonic form; buboes (85% cases), diarrhea (septicemic
plague), abdominal pain Chronic (>48 hr): Bloody, frothy sputum; buboes suppurate
Tender, swollen lymph nodes with red, edematous overlying skin, often in inguinal and axillary regions.
Focused History: Do you have tender lymph nodes? If so, are they so sore that touching or movement can
cause great discomfort? (typical in bubonic form) Can you see or recall a flea bite (a scab, pustule, ulcer)
near the bubo? (typical exposure) Have you been handling rodents lately? (typical exposure) How long have
symptoms been present? (Plague is usually rapidly progressive)
Objective: Signs
Using Basic Tools:
Inspection: Acute (< 48 hrs): Fever to 104°F; a skin lesion at site of flea bite (25%); lethargy; tachycardia
110-140; hypotension; toxic appearance; Pneumonic: respiratory distress, tachypnea Chronic (>2 weeks):
Can see meningeal signs: Plague meningitis is particularly associated with axillary buboes.
Auscultation: Sub-acute (up to one week): Rales if pneumonic
Palpation: Acute (< 48 hrs): Buboes Sub-acute (up to one week): Buboes may start to recede, also
could suppurate.
Using Advanced Tools: Lab: Gram's stain of bubo needle aspirate (usually need to inject and withdraw
some saline to get sample) or sputum may show gram-negative coccobacillus with a bipolar (safety pin)
staining appearance. In severely septicemic patients this may even be seen with a Gram's stain of blood.
CXR: Can be normal but rapidly progress to diffuse pneumonitis (increased markings throughout lung fields).
Assessment:
Differential Diagnosis: Tularemia, enteric fever, rickettsial infection, acute lymphadenitis, dengue, typhus
and Hantavirus.
Plan:
Treatment
Primary: Gentamicin 2 mg/kg load then 1.7 mg/kg q 8 hours IV (adjust lower if kidney dysfunction as noted
on urinalysis)
Alternative: Doxycycline 200 mg first day then 100 mg bid x 10-14 days
NOTE: If meningitis develops, use ciprofloxacin 750 mg po bid or chloramphenicol 50 mg/kg/day x10-14
days.
Patient Education
General: Plague is a quarantinable disease subject to World Health Organization (WHO) international health
regulations.
Activity/Diet: As tolerated
Prevention and Hygiene: Remove any fleas. Isolate with respiratory and secretion precautions for first 48
hours of treatment. Avoid sick and dead animals. Wear gloves when handling carcasses. Post warnings
near areas of known plague. Use licensed vaccine, which protects against bubonic but not pneumonic plague.
Provide post-exposure prophylaxis: Doxycycline 100 mg po bid x 7 days.
No Improvement/Deterioration: Evacuation.