A hair pull test shows fragmented hairs of varying lengths.Challenge: What is the cause of this patient's hair loss?
Image shown under Fair Use.
I put together these medical challenges. The cases are hypothetical and do not necessarily represent actual or typical presentations of medical diseases. Disclaimer is at the bottom of this page.
This is a 3 year old boy with a history of nephrolithiasis who bites himself; his lower lip is mutilated and he has a wound on the dorsum of his hand. His tongue is spared. He has uncontrolled motor movements with action dystonia and baseline hypotonia. He also has delayed developmental milestones and mental retardation. Labs show a macrocytic anemia.

A 60 year old man with diabetes complicated by dialysis-dependent renal failure, mitral valve prolapse, benign prostatic hyperplasia, and dyslipidemia presents with fever, chills, night sweats, and a rash. Unfortunately, he can't give a really good history.
You are on a medical mission in Africa where you take care of numerous children like the ones shown above. Height and weight are nearly normal for age. They all have anorexia, a palpable liver, pitting edema, hair that falls out, and dry atrophic peeling skin.
A 60 year old man presents with a gradual onset of difficulty walking which has worsened over the last few weeks to months. He feels weak, unsteady, and uncoordinated in his legs. He's also recently developed poor coordination of the arms, dysarthria, and intermittent diplopia and blurred vision. His past medical history is only significant for a few episodes of alcoholic hepatitis and a remote appendectomy. His social history is significant for being a heavy drinker for 25+ years.
A 25 year old man swimming off the coast of Northern Australia feels a sharp mildly painful sting. He returns to shore, and 30 minutes later, begins to feel severe generalized back, chest, and abdominal pain, nausea, vomiting, sweating, and agitation. Physical exam shows hypertension and tachycardia. About 12 hours later, he develops myocardial injury and pulmonary edema. The tiny jellyfish shown above, about 2cm in diameter with long tentacles, was identified as the culprit.
This image from a 40 year old man shows a shaved surgical site at the location of the pathology. He initially presented with heaviness or dull discomfort in his pelvis worse with straining, lifting, and prolonged standing. This is relieved by lying down. He noticed this bulge in the right groin, and it is more pronounced with coughing.
I have a friend with these symptoms!