(Serious) Doctors of reddit, what is the rarest condition you have diagnosed and how did you come to that conclusion?

General Surgeon here. I picked up histoplasmosis on a chest x-ray. I was doing some locum work in a small hospital in Montana. We were having our daily rounds; the hospital was so small that the only other MD was a Hospitalist. She asked me to see this 40-something lady who presented with a fever of 104. Her WBC was normal and so was the differential. On CT, she was noted to have a small cyst on her spleen (likely due to remote trauma). The other MD told me about the patient during daily rounds and pulled up the patient's chest x-ray. It looked like histo. (I was born and trained in Arkansas. Lots of chicken farms. I know histo.) The Hospitalist was worried about a splenic abscess. I interviewed the patient. After 40 minutes and several questions about travel and pets, the only info gleaned was that the patient restored old houses. I called her partner to see if he noticed any bird droppings or anything else to suggest histo. He said no. After another 40 minutes on the phone, I had to end the call; because, I needed to find another possible diagnosis. Just as I was hanging up the phone, he said, "she has pigeons. She lives in a camper and has pigeons." BINGO! I go back to the patient's room, as she did not mention pigeons when I asked her about pets. Yep...she has 9 of them. "Some of them are homers."

I ordered the appropriate urine studies, and the Hospitalist started the patient on IV antifungals. There were 4 cases diagnosed in Montana that year. My name didn't show up in the CDC MMWR... That would have been a good line on my CV. I did feel like a pimp; because, I pulled histo out of my ass in front of the majority of the hospital staff.

The patient did well...and moved her pigeons to an outdoor pen.

/r/AskReddit Thread