When people go camping, you should be thinking of zoonotic infections. Fun fact, New Mexico leads the country in cases of plague. Yes, that plague: Yersinia pestis. The “bubonic” part of bubonic plague refers to the swollen infected nodes (“buboes”) characteristic of the disease, which often involve the groin (bubo is the Greek word for groin, who knew?). In this case, they’re also describing a necrotic epitrochlear node. Classic treatment is with aminoglycosides, which bind to the 30s ribosomal subunit. (Note that Tularemia, caused by another gram-negative bacteria Francisella tularensis can present similarly but is more common in the midwest. Regardless, the two are often lumped together, the antimicrobial treatment is similar, and the answer in this case would be the same).

(Free 120, 2019 Update)

The patient is presenting with headache, myalgia, fatigue, sudden onset of high fever and chills, unilateral swollen and tender lymph nodes, and buboes containing malodorous pus discharge has the bubonic plague and must be treated with aminoglycosides which interfere with ribosomal assembly. The bubonic plague is caused by Yersinia pestis – a small facultative intracellular gram-negative bacilli. It is transmitted from rodents to fleas to humans. Reservoirs include rats, squirrels, and prairie dogs of the southwest US. The bubonic plague presents with hot, red swollen lymph nodes (especially in the inguinal regions), and skin hemorrhages with black discoloration.

Alternatively, this patient may be infected by Francisella tularensis – another small gram-negative coccobacillus that is facultative intracellular within macrophages. The organism enters at site of infection, then travels in macrophages to reticuloendothelial organs where it produces caseating granulomas. It is transmitted from wild animals to Dermacentor tick/deer flies to humans. Ulceroglandular Tularemia is one of the presentations and presents with black skin ulcer at the site on infection, swollen, red lymph nodes; all of which closely resembles the bubonic plague.

Both Francisella tularensis and Yersinia pestis infections can be treated with an aminoglycoside

You will remember that G6PD deficiency causes red blood cells to break down in response to certain stressors, infections, and drugs. The patient’s symptoms are a manifestation of indirect hyperbilirubinemia due to hemolysis (RBC breakdown). Sulfa, fava beans, nitrofurantoin, isoniazid, and antimalarials (e.g. primaquine) are the common test favorites.