When Missing a 'Zebra' Can Land You in Court

Mark Crane


February 20, 2018

In This Article

A Delayed or Wrong Diagnosis Can Be Lethal

One of the most famous axioms in medicine is, "When you hear hoofbeats, think horses, not zebras."

Every medical school student is taught that most diagnoses are more likely to involve common conditions and diseases than rare ones. Focus on the likeliest possibilities rather than the obscure ones.

That makes good sense—except when the physician is confronted with a patient who may have one of 7000+ rare diseases listed by the National Institutes of Health, each disease affecting fewer than 200,000 people in the United States. Together, rare diseases affect almost 30 million Americans or about 1 in 10 people. Globally, an estimated 350 million people have rare diseases.[1]

Physicians are generally unlikely to face a malpractice suit for misdiagnosing a rare disease. However, even though a disease might be rare, the results of a delayed or wrong diagnosis can be devastating or lethal. Juries have awarded millions of dollars in cases involving both primary care physicians and specialists. The doctors and hospitals not only missed the right diagnosis but did too little to find out why the patient failed to improve after their early treatment.

"We just don't get a lot of these claims," said William S. Kanich, MD, JD, chief medical officer for MagMutual, a Georgia-based medical malpractice carrier. "It isn't usually the rare diseases doctors get sued for. It's the common ones—missing heart attacks, appendicitis, cancer, pneumonia, etc.

Misdiagnosis Is Common

"The standard of care in rare disease cases, frankly, is to miss them," said Dr Kanich. "Juries tend to give physicians the benefit of the doubt in most cases. The key question for the doctor is: How do you know what you don't know? In the first 2 years of medical school, we'd often hear about pheochromocytoma, a malignancy on the adrenal gland, and other rare diseases. But in 15 years of practice, I've never seen one. It's difficult to diagnose a disease like that."

"If the patient isn't responding the way you think he should, that's when doctors have to ask themselves, 'What am I missing? What else could it be?'"


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