Discuss the differential diagnosis (DD) process.
QUESTION
Discuss the differential diagnosis (DD) process. Identify 3 different DD processes used in clinical practice. Describe the risks/benefits of these 3 processes.
Discuss the differential diagnosis (DD) process.
ANSWER
Differential diagnosis is the process by which a doctor distinguishes between two or more conditions that may be causing a person’s symptoms.
A doctor may have a single theory as to the cause of a person’s symptoms when making a diagnosis. They may then request additional tests to confirm their suspected diagnosis.
However, in many cases, no single laboratory test can definitively diagnose the cause of a person’s symptoms. This is due to the fact that many conditions have the same or similar symptoms, and some manifest in a variety of ways. A doctor may need to use a technique known as differential diagnosis to make a diagnosis.
This article defines differential diagnosis and gives some examples. It will also explain how to interpret differential diagnosis results.
What exactly is differential diagnosis?
When there is no single laboratory test that can diagnose the cause of a person’s symptoms, a doctor may perform a differential diagnosis.
Making a list of possible conditions that could be causing a person’s symptoms is part of differential diagnosis. The doctor will compile this list using information obtained from:
the individual’s medical history, including self-reported symptoms
physical examination results
diagnostic examination
A doctor may have one theory about the cause of a person’s symptoms and test for that one condition, which is less common in the diagnostic approach.
Many conditions, however, share some of the same or similar symptoms. This makes it difficult to diagnose the underlying condition using a nondifferential diagnostic approach.
When there are multiple potential causes to consider, a differential diagnostic approach is useful.
The objectives of differential diagnosis are as follows:
reduce the working diagnosis
medical diagnosis and treatment
rule out any life-threatening or time-sensitive conditions
allow the doctor to make the proper diagnosis
What are the procedures?
Differential diagnosis can be time-consuming. A doctor will use the following steps to determine the correct diagnosis.
1. Take a medical history
A doctor will need to take a complete medical history when preparing for differential diagnosis. They may ask you the following questions:
What are your signs and symptoms?
How long have you been suffering from these symptoms?
Do certain conditions run in your family?
Have you recently traveled outside of the country?
It is critical that all questions be answered honestly and in as much detail as possible.
2. Conduct a physical examination
A basic medical examination will be performed next by a doctor. The following items may be included in the examination:
determining a person’s heart rate
taking their pulse rate
listening to their lungs or examining other parts of their body where symptoms may be coming from
3. Perform diagnostic tests
Following a medical history and physical examination, the doctor may have some ideas about what is causing a person’s symptoms.
To rule out certain conditions, they may order one or more diagnostic tests. These tests may include:
blood examinations
urine examinations
diagnostic imaging tests, for example:
ultrasound examination
X-ray
MRI examination
A CT scan
endoscopy
4. Refer the individual for referrals or consultations.
In some cases, the doctor may believe that they lack the specific expertise to determine the exact cause of a patient’s symptoms. They may refer the person to a specialist for a second opinion in such cases.
Multiple doctors reviewing one patient during differential diagnosis is not uncommon.
Differential diagnoses examples
Three examples of common differential diagnoses are provided below.
Chest ache
Chest pain is a symptom that can be caused by a variety of factors. Some are minor, while others are severe and necessitate immediate medical attention.
When a patient complains of chest pain, a doctor will need to ask questions to determine the location, severity, and frequency of the pain.
These inquiries could include the following:
What are your thoughts? Describe the sensation.
Where does it cause pain?
Is the pain spreading to other parts of your body?
Was there anything that caused the pain?
How long has the pain been going on?
Is there anything that has made the pain better or worse?
Have you had any additional symptoms?
The doctor will hopefully be able to classify the chest pain as one of the following types by asking these questions:
Cardiac conditions are those that affect the heart. Unstable angina and a heart attack are two examples.
Pulmonary: These are conditions that affect the lungs. Here are some examples:
embolism of the lungs
hypertension of the lungs
pneumonia
These conditions are related to the digestive system. GORD (gastroesophageal reflux disease), which can lead to Barrett’s esophagus, and peptic ulcers are two examples.
Musculoskeletal conditions are those that affect the muscles, bones, and connective tissues. Fractures of the ribs and other trauma to the chest wall or sternum are examples.
Miscellaneous: This category contains information about other possible causes of chest pain, such as:
anxiety
Anxiety attacks
lymphoma
Once the doctor has narrowed down the type of pain, diagnostic tests will be ordered to determine the potential cause of the pain. Among these tests are:
electrocardiogram (EKG)
echocardiogram (echo)
endoscopy
X-ray
Headaches
Headaches are a common complaint. As a result, it can be difficult for a doctor to distinguish between a harmless irritation and a serious health concern.
A doctor will look for certain red flags that indicate that the headache is more than just an inconvenience during differential diagnosis. These red flags include severe headaches that appear suddenly and headaches that occur after head trauma.
Sudden onset of severe headache could indicate a number of underlying conditions, including subarachnoid hemorrhage or pituitary apoplexy. Headache after a head injury could be caused by intracranial hemorrhage, subdural hematoma, or epidural hematoma.
To determine whether or not the headache poses a serious risk to the person’s health, the doctor will ask the following questions:
Is the headache coming on gradually or suddenly?
Was there anything that caused the headache?
Where is the suffering?
Is the pain spreading to other parts of your body? If so, where is it?
What kind of pain are you experiencing? Is it throbbing, stabbing, dull, or another sensation?
On a scale of 1 to 10, how severe is your pain?
Do you get headaches on a regular basis?
Is this your first headache or your worst?
Is this a headache like you usually get?
Do you have any other symptoms in addition to the headache?
A neurological exam may be performed in some cases by the doctor. This exam may assess a variety of factors, including:
pupils’ reactions to light
touch reactions or sensations
profunde tendon reflexes
motor ability
gait
A medical history and physical exam can help to narrow down the causes of headache. Neuroimaging tests, such as CT or MRI scans, can assist in ruling out or confirming certain diagnoses.
Stroke
Stroke necessitates immediate diagnosis and treatment. As a result, when considering the possibility of a stroke, many doctors use a differential diagnostic method.
During a physical examination, a doctor will look for the following stroke symptoms:
confusion
decreased mental alertness
coordination and balance issues
issues with vision
face, arm, or leg numbness or weakness
difficulty communicating or speaking
A person’s medical history will be reviewed by the doctor to see if they have any medical conditions that may increase their risk of stroke. These are some examples:
elevated blood pressure
high cholesterol levels
diabetes
carotid artery disease and atherosclerosis
Following that, the doctor will order one or more of the following tests:
blood examinations
a CT scan to look for possible brain bleeding
an MRI scan to look for signs of damage in the brain tissue
an ECG or EKG to look for heart problems that may have contributed to the stroke
How to Interpret the Findings
Before receiving a definitive diagnosis, a person may need multiple in-office examinations and diagnostic tests.
Some patients may receive several negative test results before receiving a diagnosis. Each negative test result, on the other hand, brings the doctor one step closer to determining the cause of a person’s symptoms.
Some people may need to begin treatment before their diagnosis has been confirmed by a doctor. This could be the case if one of the possible causes of a person’s symptoms necessitates immediate treatment to avoid further complications.
A person’s reaction to a particular treatment can reveal important information about the cause of their symptoms.