Immunology

A previously healthy 9-year-old boy developed acute upper left quadrant and epigastric abdominal pain, nonbloody nonbilious vomiting, and decreased oral intake.

A 54-year-old woman presented to an outpatient office for recurrent erythema and tenderness of the right lower eyelid and cheek. She was not taking any medications, and her health was excellent. She denied...

A 38-year-old man received a booster dose of the Pfizer COVID-19 vaccine about 6 months after completing two doses of the Moderna COVID-19 vaccine primary series. Following his Pfizer booster dose, the...

A 37-year-old woman presented to a dermatology clinic for evaluation of recurrent, pruritic, inflamed plaques on her neck, thigh, back, and shoulder. The lesions had flared at irregular sporadic intervals...

A 3-year-old boy with no medical history presented to the emergency department for worsening cough, decreased appetite, tachypnea, and chest pain for 2 nights.

Hemophagocytic lymphohistiocytosis results from an unsuppressed immune response leading to hypercytokinemia (cytokine storm), which mimics sepsis.

Angioedema is a painless, non-pitting, localized edema that occurs within the deep layers of the skin. There are known genetic differences that influence angioedema, and the attacks have been linked to sex...