Saturday, October 22, 2016

Case of the Day

The art, science, history, and process of differential diagnosis is fascinating to me. Although this blog is not meant to hone that skill per se, it reflects my interest in pattern-recognition, heuristics, and fun medical trivia. For those interested in a deeper methodological study of the DDX, there are many other textbooks, articles, and resources on this (I personally enjoyed reading Clinical Problem Solving by NEJM).

This project was inspired by one of my best teachers, Dr Andy Josephson of UCSF neurology who had a very similar set-up during our neuroscience block in the first year of medical school, about ten years ago. We all learn differently, and for me, it was a really sticky way of adhering the reams of knowledge we had to acquire to my brain. I began this blog as a way of active learning, to encourage myself to read UpToDate, collect images, and keep track of diseases I wanted to know more about. Indeed, over the last ten years, I've kept scraps of paper and email drafts containing lists of diseases, signs, symptoms, and syndromes that come up for patients I meet, lectures I attend, articles I read, and conversations I have. Some of the diseases still on the list that I wanted to write a Case of the Day on but didn't get to include: tinnitus, splenic vein thrombosis, percheron stroke, cavitary pulmonary nodules, CMV pneumonitis, IBS, isopropyl alcohol intoxication, MCA CVA (insular ribbon sign), basal ganglia CVA (comma sign), sterile pyuria, anaphylaxis, air embolism, compartment syndrome (abdominal and extremity), quinidine effect, bupropion overdose. I'm not sure where these come from; they're just culled over time.

I've learned an incredible amount from this blog, and I hope you have gained something too. I have such great appreciation for my readers. I've had about 350,000 pageviews, mostly from the U.S., but also Canada, France, India, Brazil, the UK, Ukraine, Australia, Algeria, and Israel. In these thousand medical mysteries, I procured 1127 pictures. My backup file of the entire blog contents is 1445 pages long (my answers document is 188 pages). I'm sure I spent at least several weeks of my life working on this project. It's been wild.

I've never been good at saying goodbye to things, but it's time for me to move onto other projects despite the time invested and momentum built here. I may go through the cases someday and make small adjustments or organizational changes. With time, some of the medical information here may become obsolete or change, but I hope it remains a useful resource for readers.

Thank you all for your time, your kind words, and your participation. It has meant a great deal to me. Please feel free to contact me (I will reply to any comments) and I wish you all the best in your futures.

Craig Chen MD

Thursday, October 6, 2016


Wow! This is actually the last Case of the Day. I made it to 1000 cases over 9 years! I'll write a post after this just to tie things up, but this will be the last medical mystery. I never meant for Case of the Day to last forever, and it's been an incredible amount of work to get here. I'm pretty happy to say there are more cases here than most textbooks and all of them are backed by reasonable references.

This last case I actually wrote at the very beginning, nine years ago. It was sort of a prototype which I never published. There is some poetry in having it bookend this project. I will write more in a closing post, but thank you all for reading, responding, learning, and teaching me.

With respect, love, and passion,


A 30 year old man with a history of "allergies" presents for an infertility workup because he and his wife have been unsuccessful in getting pregnant for over a year. Her workup is apparently normal. When you ask the husband, he notes that he has a chronic cough and mild shortness of breath. You wonder about cystic fibrosis and order a chest X-ray:

Challenge: What syndrome does he have?

Image shown under Fair Use.

Tuesday, October 4, 2016

Last Few Cases

Sorry, I was on call yesterday, and Case of the Day totally slipped my mind. Here's a pretty good one on a disease that was on critical care boards. This week is busy for me but I'll put up answers for the last few cases soon.

A patient with leukemia undergoes an autologous hematopoietic stem cell transplant. Two weeks later, she develops a temperature of 38.5C and a maculopapular rash initially concerning for graft-versus-host disease. She feels short of breath, and her room air saturation is only 84%. Review of systems is positive for diarrhea, but stool infectious workup is negative. Chest X ray shows bilateral air-space opacities. Her blood cultures, urinalysis, and sputum are negative; a procalcitonin is normal. A bronchioalveolar lavage is performed which is unremarkable. Her echo does not show heart failure though she does have some edema, weight gain, and ascites. Labs show hypoalbuminemia.

Challenge: What is your diagnosis?