A 15-year-old boy is evaluated for fever, headache, malaise, and cough 3 weeks after returning from summer camp. Lung auscultation is unremarkable. Chest x-ray reveals nodular infiltrates. The patient's blood samples are collected for analysis in anticoagulated tubes, which are transported submerged in ice; when taken out several minutes later, turbidity and clumping are noted. Warming the tube to body temperature leads to rapid dissolution of the clumps. Which of the following organisms is most likely responsible for this patient's condition?

Question

A 15-year-old boy is evaluated for fever, headache, malaise, and cough 3 weeks after returning from summer camp.  Lung auscultation is unremarkable.  Chest x-ray reveals nodular infiltrates.  The patient's blood samples are collected for analysis in anticoagulated tubes, which are transported submerged in ice; when taken out several minutes later, turbidity and clumping are noted.  Warming the tube to body temperature leads to rapid dissolution of the clumps.  Which of the following organisms is most likely responsible for this patient's condition?

Quizplus · Accepted Answer

Eductional Objective: Infection with Mycoplasma pneumoniae can result in the formation of cold agglutinins, which are IgM antibodies (primarily) that bind red blood cells and cause clumping/agglutinations at low body temperatures.  Other illnesses resulting in cold agglutinin formation include infectious mononucleosis and certain hematologic malignancies.

A 15-Year-Old Boy Is Evaluated for Fever, Headache, Malaise, and Cough