When you start Nurse Practitioner (NP) school, you’ll begin hearing about differential diagnosis. Soon enough, these two words will become part of your daily vocabulary and central to many of your assignments. We’re discussing what differential diagnosis is, its purpose and why it’s important. At the end, I’ll be sharing a list of differential diagnosis resources that are great for school and for clinical practice too.
What is differential diagnosis?
Simply speaking, it is a list of possible conditions that could be causing a patient’s symptoms and signs. Typically, the differential diagnosis includes common conditions and must not miss diagnoses. Not to miss diagnosis = if you don’t recognize this problem, it could cause serious complications or death. You’ll likely learn a lot about differential diagnosis in your primary care/ management courses.
What’s the purpose?
A list of differential diagnoses helps guide your workup of the patient’s problem. Firstly, it guides what questions you need to ask to get more information about his symptoms. Secondly, what physical exam you should complete. And finally, what diagnostic testing or referrals need to be ordered. With further diagnostic testing, exam, and history, the list of possible conditions can be narrowed down. Ideally, this process leads to the correct and final diagnosis.
Can you give an example of what differential diagnosis looks like?
Say a 12-year-old patient comes in with acute abdominal pain, nausea, and vomiting. Before seeing the patient, you think about common conditions and serious conditions that you need to consider for the patient. You consider possible causes of abdominal pain plus nausea/vomiting including gastroenteritis, constipation, appendicitis, UTI, or intussusception as a few examples. When you go and see the patient, you’ll get more information by asking questions and completing your exam with special attention to rule out serious/life-threatening conditions.
You ask specific questions and do special physical exams to determine whether this patient may have appendicitis. Basically, you need to make sure this patient does not have appendicitis or intussusception before you send him home with a diagnosis of gastroenteritis. Creating a list of differential diagnosis forces you to consider possible causes of this patient’s symptoms. This ensures you don’t miss a potentially serious or emergent cause of your patient’s symptoms. It also helps you arrive at the correct diagnosis.
Why is differential diagnosis important?
Differential diagnosis is an essential skill for NPs, Physicians, and Physician’s Assistants (PAs) to make an accurate diagnosis. By creating a list of possible diagnoses, then further narrowing it down to probable diagnoses as you collect more information, you are in a strong position to make the correct diagnosis and provide the best treatment.
What are the best resources for differential diagnosis?
Apps/Webpages
Cost: $99.95 for a 1 year subscription.
Available as an app, webpage, and a book. It is a comprehensive resource not only for differential diagnosis, but it has information for diagnosing and treating more than 500 diseases and conditions. In addition, your subscription also includes access to Diagnosaurus DDx as listed below.
Cost: $199/year for students and $559/year for NPs, but it is often available through school, work or your clinical sites at no cost to you.
Though not as easy or straightforward to find in other apps, UpToDate can be searched to find a list of differential diagnoses. There is no one way to find this information, but you can usually find it in 2 different ways. Method #1 – Search, for example, “cough differential diagnosis” to find a list of other diagnoses to consider. Or method #2 – It is usually in the Clinical Manifestation and Diagnosis topic page for each condition or disease.
Cost: $174.99/year. It may be available for free through school, work or your clinical site.
Differential Diagnosis can be easily found in the disease lookup section of the app or webpage. To get the disease lookup feature, you’ll have to upgrade from the free version.
Cost: $4.99.
Search by a sign, symptom or disease to see what diagnoses you should consider.
Textbooks
Advanced Health Assessment and Clinical Diagnosis in Primary Care
Cost: $88 *as of 8/20/20
This book is very helpful when formulating your differential diagnosis. It is organized by chief complaint. Under each chief complaint, you’ll see possible differential diagnoses based on symptoms and exam findings.
Symptom to Diagnosis – An Evidence Based Guide
Cost: $66 *as of 8/20/20
This book is all about the diagnostic process including differential diagnosis for common symptoms in primary care and internal medicine.
Current Medical Diagnosis and Treatment
Cost: $76.50 *as of 8/20/20
This book gets updated every year. It is another great resource for formulating your differential diagnosis plus so much more.
For Derm
We all know how challenging rashes and other skin conditions can be to diagnose. This app makes it a little less daunting. I highly recommend checking it out! It allows you to put in signs and symptoms for skin issues and helps you build a differential diagnosis list complete with pictures of each condition.
Cost: $399.99/year. Definitely expensive – ask your school, work or clinical site if this is available for you to access.
Differential Diagnosis and Resources Summary
Differential Diagnosis is a challenging but fun and important skill to learn in Nurse Practitioner school. By knowing what common conditions and serious or rare conditions could be causing your patient’s symptoms, you’ll be better equipped to ask the right questions, do an appropriate exam, and order the right diagnostic tests. Finally, these resources are all helpful tools to have as you think through your differential diagnosis.
Share below – do you find differential diagnosis challenging? What are your favorite resources to use?
Make sure to check out other recent posts and visit the resource page:
- Interview Tips for New Nurse Practitioners
- FNP Certification Exam Study Tips
- Your NHSC Loan Repayment Program Guide
- Lessons Learned as a New Nurse Practitioner
- New Graduate Nurse Practitioner Checklist
Disclosure: Some of the links above are affiliate links. This means that, at zero cost to you, I will earn an affiliate commission if you click through the link and finalize a purchase.