Brucellosis vs Tularemia and plague
How to tell Brucellosis and Tularemia and plague apart when a board question makes them look alike.
Brucellosis is undulant dairy/livestock fever; tularemia is rabbit/tick ulceroglandular fever; plague is flea/rodent painful bubo or pneumonic sepsis.
Side by side
Brucellosis causes undulant fever, sweats, malaise, arthralgia, hepatosplenomegaly, and exposure to unpasteurized dairy or livestock.
Tularemia causes high fever with ulceroglandular disease after rabbits/deer flies/ticks; plague causes painful buboes, sepsis, or pneumonic disease after fleas/rodents.
Brucella survives intracellularly in macrophages after animal or unpasteurized dairy exposure, causing relapsing systemic infection.
Francisella tularensis causes highly infectious zoonotic disease; Yersinia pestis blocks phagocytosis and causes necrotic lymphadenitis or pneumonia.
Undulant fever, night sweats, osteoarticular symptoms, hepatosplenomegaly, and Brucella blood culture/serology support brucellosis.
Skin ulcer with regional nodes supports tularemia; very painful bubo with sepsis or bloody pneumonia supports plague.
The trap
All are zoonoses with fever, so the exposure and lymph node/ulcer/bubo pattern decide.
The repair move
For zoonotic fever, attach the animal exposure to the signature fever or lymph-node pattern.
Try a free question
CoreA farmer who drinks unpasteurized goat milk has recurrent undulating fevers, drenching sweats, malaise, arthralgias, and hepatosplenomegaly. Which diagnosis is most likely?
Show answer and explanation
Answer: A. Brucellosis. Unpasteurized dairy/livestock exposure with undulant fever, sweats, arthralgias, and hepatosplenomegaly supports brucellosis.
Why the other choices are tempting
- B. Tularemia often causes ulceroglandular disease after rabbit/tick/deer fly exposure.
- C. Plague causes painful buboes or pneumonic/septicemic disease after flea/rodent exposure.
- D. Typhoid fever is Salmonella Typhi enteric fever.
- E. Leptospirosis follows animal urine/freshwater exposure.
Flashcards
Tap a card to flip it.
What exposure supports brucellosis?
Unpasteurized dairy or livestock exposure supports brucellosis.
What fever pattern supports brucellosis?
Undulant or relapsing fever with sweats supports brucellosis.
Quick answers
What is the fastest way to tell Brucellosis from Tularemia and plague?
Brucellosis is undulant dairy/livestock fever; tularemia is rabbit/tick ulceroglandular fever; plague is flea/rodent painful bubo or pneumonic sepsis.
What is the key clue for Brucellosis?
Brucellosis causes undulant fever, sweats, malaise, arthralgia, hepatosplenomegaly, and exposure to unpasteurized dairy or livestock.
What is the key clue for Tularemia and plague?
Tularemia causes high fever with ulceroglandular disease after rabbits/deer flies/ticks; plague causes painful buboes, sepsis, or pneumonic disease after fleas/rodents.
What is the common trap with Brucellosis vs Tularemia and plague?
All are zoonoses with fever, so the exposure and lymph node/ulcer/bubo pattern decide.