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
Saturday, October 22, 2016
Thursday, October 6, 2016
1000
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,
Craig
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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.
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,
Craig
-
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?
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?
Friday, September 30, 2016
Well?
ECG Wave Maven has been my go-to resource for great EKG's. Created by Beth Israel Deaconness Medical Center in 2001, it has an incredible number of fascinating cardiograms, cases, and explanations. It's an unsurpassed repository for learning and education, and I hope you check it out.
This EKG comes from a middle aged man with vague chest pain. Initial troponins are negative.
Challenge: What does the EKG show? (Click for full image)
Image shown under Fair Use.
This EKG comes from a middle aged man with vague chest pain. Initial troponins are negative.
Challenge: What does the EKG show? (Click for full image)
Image shown under Fair Use.
Thursday, September 29, 2016
Exit Here
This CT scan is from a young woman with a pulsatile supraclavicular mass on the left side. She also gets pain with exertion in that arm. Sometimes, she gets pallor, paresthesias, and coldness in her left hand, and she was initially diagnosed with Raynaud's but wants a second opinion. There is no history of trauma. She has no other medical problems. Her pulses on that arm are diminished. There is no musculoskeletal tenderness.
Challenge: This is the least common version of what syndrome?
Image shown under Fair Use.
Challenge: This is the least common version of what syndrome?
Image shown under Fair Use.
Wednesday, September 28, 2016
Tuesday, September 27, 2016
Delay
A 50 year old smoker comes in with severe headache, altered mentation, and this CT scan. He goes to interventional radiology for a procedure. Over the next several days, he slowly improves. A week later, though, he suddenly gets worse. He becomes more confused and somnolent. CT and EEG do not explain his neurologic exam. Ultrasound confirms the diagnosis.
Challenge: What do you suspect?
Image shown under Fair Use.
Monday, September 26, 2016
Postpartum
A woman has postpartum hemorrhage from placenta previa after a spontaneous vaginal delivery. Despite adequate resuscitation, she has persistent hypotension and spends several nights in the ICU. Eventually, she is discharged home, though her blood pressures remain quite low. She has some symptoms of orthostasis but really wants to go home. On her first postpartum visit, she notes that she hasn't been lactating. A few weeks later, she also complains of fatigue and anorexia. A year later, she has persistent oligomenhorrhea.
Challenge: What syndrome do you suspect?
Challenge: What syndrome do you suspect?
Friday, September 23, 2016
What'd I Miss?
Challenge: What kind of highly unstable fracture is shown above?
P.S. Taking a break on cases this weekend, back on Monday.
Images shown under Fair Use.
Thursday, September 22, 2016
Sphygmomanometer
I can't believe I've written 9 years of cases, almost a thousand of them, and didn't get to this one. This is the the kind of medical trivia I like.
You pump this blood pressure cuff on the arm of a patient to 200mmHg. The phone rings and you go and answer it. The BP cuff is left inflated for three minutes, and the patient begins having adduction of the thumb, flexion of the MCP joints, extension of the IP joints, and flexion of the wrist.
In addition, when you tap the patient just anterior of the ear, she gets contraction of the ipsilateral facial muscles.
Challenge: What's going on? What two signs are described above?
Image is in the public domain.
Wednesday, September 21, 2016
Tuesday, September 20, 2016
My Fair Lady
My goal for the last handful of cases on this blog is to actually post a case a day; it always bothered me a little to have a blog titled "Case of the Day" that was only running twice or thrice weekly posts. This may not actually happen, but I'm trying to go out with a bang.
These CT images are from an older Caucasian woman infected with a nontuberculous mycobacterium. She has a chronic cough but no known chronic lung disease. She tries to hide her cough.
Challenge: What syndrome is this?
Image shown under Fair Use.
These CT images are from an older Caucasian woman infected with a nontuberculous mycobacterium. She has a chronic cough but no known chronic lung disease. She tries to hide her cough.
Challenge: What syndrome is this?
Image shown under Fair Use.
Monday, September 19, 2016
Africa
This disease is common in rural Africans, but can also be seen with travelers returning from Africa or the east Caribbean. It presents as a mild illness with headache, fever, and myalgias. Solitary or multiple eschars as shown above are common, along with regional lymphadenopathy. There may be a scant generalized rash, and uncommonly, subacute neuropathy or myocarditis.
Challenge: What is your diagnosis?
Image shown under Fair Use.
Thursday, September 15, 2016
Post-Op
An obese (BMI 40) man with diabetes, peripheral artery disease, and tobacco abuse undergoes a CABG. He actually had a prior cardiac surgery to repair an aortic valve five years ago. Over the last year, he developed increasing shortness of breath. Workup revealed coronary disease so he underwent a redo sternotomy and bypass graft with an internal mammary artery.
Postoperatively, he has fever, tachycardia, and persistent chest pain. There is crepitus and edema of the chest wall as well as a crunching sound synchronous with the heart beat and heard by auscultation. White count is elevated.
Challenge: That weird crunching sound has a name - what is it? Also, what's the diagnosis?
Monday, September 12, 2016
Vessel
This vessel starts at the junction of the left subclavian and left internal jugular veins, passes lateral to the aortic arch, and drains into the right atrium via the coronary sinus.
Challenge: What is this rare anomalous vessel?
Image shown under Fair Use.
Thursday, September 8, 2016
Whoops
A 70 year old patient comes in with septic shock. She is febrile, tachycardic, hypotensive, tachypneic, and hypoxemic. Her labs show a leukocytosis, elevated lactate, and elevated procalcitonin. Chest X-ray shows a right lower lung focal opacity. She is fluid resuscitated with 5 liters of crystalloid but still has refractory hypotension. The emergency medicine intern puts in a right internal jugular central venous catheter to start norepinephrine. Later, a KUB is taken which is shown above.
Challenge: What complication happened here?
Image shown under Fair Use.
Thursday, September 1, 2016
DDX
A rapid response alert is called in labor and delivery. You rush in to find a woman who has just delivered who appears in acute respiratory distress. The obstetrician says, "she had postpartum bleeding from uterine atony, but I don't think she's lost more than a liter of blood." You can't get a history because the patient can barely speak. On exam, her breath sounds are very tight; she's not moving much air, and you hear expiratory wheezes. Her blood pressure and heart rate are fine. She's maintaining a sat of 90% with oxygen by face mask. Fluids are wide open along with oxytocin.
Challenge: She received one other medication which is causing her clinical presentation. What is it?
Image is in the public domain.
Monday, August 29, 2016
No Biopsy Needed
This patient also has bilateral parotid gland enlargement and facial nerve palsies. His review of systems is notable for fever and arthritis. He was seen by an ENT recently who ruled out parotid tumor. Apparently pathology showed granulomas.
Challenge: What's your diagnosis?
Image shown under Fair Use.
Thursday, August 25, 2016
Ventilators III
This unresponsive patient was intubated for airway protection.
Challenge: What is your goal with the ventilator?
Image shown under Fair Use.
Monday, August 22, 2016
Ventilators II
A patient with severe COPD presents with an acute exacerbation. He is intubated for hypercapneic respiratory failure and has the waveform seen above. Over the next hour, he develops significant hemodynamic instability. Suddenly, he has a cardiac arrest, and you immediately start CPR and follow ACLS.
Challenge: What is your next intervention (with the ventilator)?
Image shown under Fair Use.
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