Mystery Diagnosis: Diarrhea

The House Call Doctor tackles another medical mystery. 

Sanaz Majd, MD
4-minute read
Episode #85

Everyone loves a good mystery. That’s part of the reason medicine seems to be so popular these days. Look at shows like House and Grey’s Anatomy – we are all drawn towards the near impossible (and often implausible) medical scenarios the writers create to keep us guessing. But if you think about it, almost every patient coming in to see a real life doctor is a mystery, too. That’s why some of us become doctors—because we like to problem solve. We are medical detectives at the core.

So let’s talk about how we solve some of these medical mysteries. 

Today’s patient is 43-year-old Daniel, a normally cheerful fellow who came into my office with the chief complaint (or main symptom) of diarrhea. He thinks he may have eaten something “bad” at a local restaurant. But there are so many possible causes of diarrhea, how in the world do we tease out the real culprit?


The History

The first step toward diagnosis is to take a patient history by asking Daniel specific questions about his symptoms. The interview went like this:

House Call Doctor: How long have you had it? 

Daniel: 3 weeks

HCD: In that case, food poisoning is off the list of possible diagnoses because it often lasts around 24 hours, not days or weeks. How severe is the diarrhea?

Daniel: About 6-10 episodes per day, but when it started, it was less frequent.

HCD: How does it appear? 

Daniel: It’s watery and smells foul

HCD: Is there blood?

Daniel: No blood

HCD: Any stomach aches, nausea, or vomiting? 

Daniel: None

HCD: Any close contacts plagued with the same symptoms?

Daniel: Even though I dined with my family at the same restaurant, no one else seems to be sick.

Knowing what I know as a physician, I added a few other questions pertaining to some other possible causes of diarrhea:


Please note that all content here is strictly for informational purposes only. This content does not substitute any medical advice, and does not replace any medical judgment or reasoning by your own personal health provider. Please always seek a licensed physician in your area regarding all health related questions and issues.

About the Author

Sanaz Majd, MD

Dr. Sanaz Majd is a board-certified Family Medicine physician who graduated from Drexel University College of Medicine in Philadelphia. Her special interests are women's health and patient education.