A 43-year-old Puerto Rican man with a kidney transplant presented to the ED with 2 weeks of flu-like symptoms, nausea, and vomiting. He had plasma exchange therapy 2 months before for acute transplant rejection and has been tolerating a heightened immunosuppressive regimen. CT scans characterized opacities as possibly early tree-in-bud opacities (Fig 1A). Patient remained stable throughout hospital stay with an unremarkable workup and was discharged with doxycycline for nonspecific pneumonia.

An 80-year-old man came to the ED with fever, hematuria, and overall discomfort for 1 week. His medical history included a superficial urothelial carcinoma of the bladder for which he was adjunctively treated with intravesical Mycobacterium bovis BCG (bacillus Calmette-Guérin) immunotherapy for several months. The patient was admitted to the hospital and was initially treated with cephalosporins for a suspected complicated urinary tract infection, but his symptoms did not improve. Ten days after the initial admission, the patient developed hypoxemic respiratory failure during an episode of fever and cold chills and was admitted to the ICU.

A 53-year-old woman with no significant past medical history came to her local ED after a witnessed generalized tonic-clonic seizure. CT scan imaging of the head revealed a left frontal lobe hypodensity concerning for a mass with surrounding edema. In the previous month, she had undergone ambulatory evaluation for a subacute cough that had more recently become productive of bloody sputum. Outpatient chest radiography had demonstrated a new right lung opacity, shown on subsequent CT scan imaging to be a right upper lobe (RUL) consolidation. She was prescribed a course of doxycycline, after which sputum expectoration improved but a nonproductive cough remained. Repeat thoracic imaging was pending at the time the seizure occurred. The patient had no history of chronic lung disease or recurrent infections. There were no constitutional symptoms. She did not take any home medications on a regular basis. She was a lifetime nontobacco user. She denied use of alcohol and illicit drugs. She had previously worked in a medical office but was now spending most of her time helping her husband take care of their house and property in Kingston, New York, a town of about 23,000 people in the Hudson River Valley. She was born in the United States and had not traveled recently. She had no pets. There was no history of recent dental procedures. She was transferred to our institution for neurosurgical evaluation.

An 18-year-old man with no noted medical history from Northern India presented with history of fever for 15 days and nocturnal cough for 10 days. He denied breathlessness or wheeze. There was no medical history of asthma. He denied any current sinus-related symptoms, pruritis, skin rashes, lesions, or ulcers, abdominal pain, dysphagia, vomiting or diarrhea, numbness or tingling, joint pain, or food allergy. There was no recent exposure to a patient with TB or history of substance misuse. The patient had sought medical care 7 days before presentation for the same symptoms, and after a chest radiograph was obtained, the patient was started on an antitubercular regimen.