Not long ago, I saw a story on the Internet that Chinese living in Spain misdiagnosed a not-so-complicated disease in the local area, and later returned to China for treatment and improvement. Many years ago, there was also a female star Li Bingbing who was misdiagnosed in Australia, and later diagnosed with acute tonsillitis after returning to China, a common disease, and was cured after treatment.
Yesterday I saw the Lilac Garden WeChat public account article mentioned the misdiagnosis (see "After the misdiagnosis occurred, why are only doctors in a mess?"). "), one of the top three doctors said that the misdiagnosis rate was about 10%.
To be honest, I'm a little wary that this figure, which doesn't fit the real world, creates the illusion that the standard for a qualified doctor is less than 10 percent misdiagnosis rate. But in real work, how is this possible? Different doctors, doctors in large hospitals in large cities and small hospitals in relatively backward areas, doctors who have worked for many years to summarize experience and young doctors who have just worked for a few years, general practitioners and specialists, even doctors with the same title in the same department, this number is very different, how did the figure of 10% blurted out come from?
When it comes to misdiagnosis rates, I believe that different people, from different perspectives, will have different understandings. For patients, every visit (both outpatient and inpatient) is expected to be free from misdiagnosis, and if the diagnosis is actually wrong then it is considered a misdiagnosis. As doctors, we may think that a patient who visits multiple times for a disease can only be regarded as a misdiagnosis once. From the perspective of managers, there may be a medical error or medical accident, which is a misdiagnosis. Then, the misdiagnosis rate obtained in this way varies greatly.
Of course, today I don't want to explore how the misdiagnosis rate is calculated, but how misdiagnosis occurs and how to reduce misdiagnosis.
The previous issue introduced a case of misdiagnosis of hypertension, and if we look back and carefully consider this case, we will find that there are many misdiagnosed thinking rules in it. First, we need to understand how doctors usually think:
- We must know that the process of clinicians diagnosing diseases is not only based on the diagnostic basis stated in the book, but also subconsciously based on the epidemiology of the disease, or the probability distribution, that is, the common manifestations of common diseases are placed in the front, followed by common diseases and rare diseases, and finally rare diseases. For example, aortic coarctation is written in every textbook as a differential diagnosis of refractory hypertension, but the disease is usually diagnosed in childhood and is therefore easily overlooked when a middle-aged woman comes to the doctor. Middle-aged refractory hypertension needs to consider some endocrine tumors, so doctors will conduct relevant examinations.
- Secondly, it is precisely because clinicians are exposed to common diseases and multiple diseases on a daily basis, so the inertia of thinking is often easy to limit the diagnosis to common diseases and multiple diseases, without jumping out to expand thinking. For patients with chest pain, the first consideration is of course angina, myocardial infarction, pulmonary embolism, aortic dissection, these critical diseases, but for chest pain variant asthma (see ("Can you misdiagnose such chest pain?"). and pernicious anemia ("Young people have repeated chest pain, progressive fatigue, but the ECG is normal, and the doctors are blinded!"). Finally, it was found that the examination was not in place, and the diagnosis was wrong, and this lesson was very profound! It's easy to leave out.
- Third, many doctors are accustomed to thinking quickly, that is, making judgments with intuition. It's human nature, and sometimes intuition can get the right answer, but if you don't analyze the case in detail, it is often prone to misdiagnosis (see "Thinking Fast and Slow— What Kind of Clinical Thinking We Need to Have").
So, why did the doctor misdiagnose?
Objectively speaking, the fundamental reason lies in the complexity of life activities. For example, acute appendicitis usually presents with metastatic right lower quadrant pain and fever, but if the patient presents with only fever and no abdominal pain, you will face a differential diagnosis of a large number of fevers, and it is more likely that it is difficult to consider acute appendicitis in the first place. Similarly, for patients with aortic dissection, some do not have severe tearing chest pain, but may have such as weakness in both lower limbs ("Why did the elderly with weak lower limbs die in the hospital only two hours") or suddenly serious abnormalities in liver and kidney function ("The drastic change in liver and kidney function is shocking that different manifestations of arterial dissection sites"), or toothache as the first symptom ("Diagnosis ┃ Toothache, the real cause is aortic dissection?!" These diverse clinical manifestations are a huge challenge for clinicians. There are also many connective tissue diseases, especially vasculitis diseases, which have a variety of clinical manifestations and are very difficult to diagnose.
Secondly, doctors have insufficient understanding of the nature of the disease, taking asthma as an example, the essence of asthma is airway hyperreactivity, so it has three clinical characteristics of recurrent, episodic and reversible, and its common and typical clinical manifestations are wheezing, dyspnea, chronic cough, chest tightness, etc. However, when some patients take chest pain as the first symptom, if the specialist does not firmly grasp the essence of the disease to analyze the problem, it is easy to misdiagnose ("Where is the problem of chest pain suffering for eight years?
The patient's symptoms will be selectively selected, without truly reflecting the process of disease change, resulting in deviations in thinking. For example, in "Fever for three weeks, the use of a variety of high-grade antimicrobials is ineffective, what should we do?" In the case of "Talking About How We Want to Diagnose and Treat Pneumonia", the main complaint in the medical record of the doctor in charge was "fever, cough, and shortness of breath for ten days", while the real situation was "cough, progressive dyspnea for 20 days, fever for 10 days". The former is susceptible to suspicion of infectious disease, while the latter is a typical history of interstitial pneumonia associated with connective tissue disease. Therefore, whether it can truly reflect the patient's condition change process is also one of the factors affecting the accuracy of diagnosis.
The lack of systematic physical examination and the omission of various key information make the occurrence of misdiagnosis inevitable. In "Alveolar lavage fluid NGS detects cat Rickettsia, but finally diagnosed lung cancer, why I said I can't superstitiously believe in NGS", the doctor who first diagnosed did not perform palpation of superficial lymph nodes, which in my opinion is the key cause of misdiagnosis. In "Decades of High Blood Pressure, Taking 6 Antihypertensive Drugs Can't Be Controlled, Are We Missing Anything?" All doctors forget to measure the blood pressure of the lower extremities for the patients, otherwise they should be able to find that the blood pressure of the lower limbs caused by the narrowing of the aortic is significantly lower than the blood pressure of the upper limbs, so as to find out the real cause of hypertension.
Misread laboratory results. With the emergence of various new technologies, we have more and more helpers in diagnosing diseases. But just as there is no complete test, any test may have limitations. Therefore, clinicians are required to synthesize all clinical data when analyzing the results of these tests, rather than relying on one or several results to make judgments. For example, I have repeatedly said that NGS results should be carefully analyzed, and the height of the D dimer to determine whether to have a pulmonary vascular CTA (see Why do I judge that a patient has a pulmonary embolism?"). 》）。
Lack of appropriate means of inspection. In some primary health facilities, the lack of lung function instruments has led to many chronic airway diseases that cannot be diagnosed in time, such as asthma and chronic obstructive pulmonary disease.