You're browsing as an anonymous user. Join the community today to view notes at your university, edit pages, and share knowledge!


From Mediwikis

Michael Edwards 02 01 2017

There is something rotten in the state of diagnosis == (with apologies to william shakespeare)

As a student you will often see doctors arranging special tests for patients without any clear idea of the diagnosis

You will also see how this leads to more and more tests, waste of time and effort, delays and, on occasion, harm to the patient

A minute’s thought at the beginning of the consultation will show up possible diagnoses, with rapid confirmation from history taking, examination and relevant tests

What’s up, doc?

(with apologies to peter Bogdanovitch)

Your first job is to find out what is up with your patient

It’s the diagnosis, stupid!

(with apologies to president bill clinton)

  • Making a diagnosis comes before treatment
  • You can make three reasonable diagnoses even before you examine the patient – see on
  • Detest tests – at this stage
  • Despite all the pressures on you, do not arrange special tests until after you have taken a full history and examined the patient

Bear these diagnoses in mind, while you continue the history, past history, review of systems, drug history, clinical examination. After all this, arrange relevant special tests

Better tests

Tests ordered at this stage will be much more relevant to confirming or ruling out the working diagnoses than tests arranged before a diagnosis has been considered

What is a diagnosis?

A diagnosis has two parts: 1 what organ? 2 what disease?

What organ? Use your knowledge of anatomy.

Eg what organ lies in the right iliac fossa?

  • Appendix
  • Terminal ileum
  • Caecum
  • Ovary
  • Fallopian tube
  • Ureter
  • External iliac artery.

what diseases can affect that organ?

Use your knowledge of pathology.

Eg what diseases can affect the appendix, say?

Use acronyms to help remember all the diseases that there are.

Eg “nice times ad”

N = neoplastic * ie “bmps” b=benign* m=malignant * p=primary * s=secondary

  • I = inflammatory*
  • C = congenital*
  • E = endocrine*
  • T = traumatic
  • I = infective*
  • M = metabolic
  • E = embolic
  • S = special
  • A = arterial
  • D = degenerative

Eg * diseases of the appendix have an asterisk. They include:

  • Carcinoid tumour
  • Adenocarcinoma
  • Acute appendicitis
  • Malrotation of the appendix to lie under the liver.
  • Yersinia infection

Start making the diagnoses

Identify six key diagnostic factors in the following order

Use the acronym “agrods” to help you remember these factors.

“agrods” = age/ gender / race / occupation / duration of symptoms / symptoms

  1. Age Date of birth is not of diagnostic value. Work out the patient’s age, which is of great diagnostic value. Eg a 20 year old patient will suffer from a range of conditions quite different from an 80 year old.
  2. Gender This will exclude all conditions of the opposite sex.
  3. Race This will point to the diseases characteristic of a particular race or country of origin. Eg. Malaria in a patient from sub-saharan africa.
  4. Occupation This will point to the diseases of that patients’ occupation and of that patient’s socio-economic group. Eg. Mesothelioma in an asbestos worker.
  5. Duration of symptoms The date of onset of a symptom , like date of birth, is not of diagnostic value. Work out the duration of symptoms for diagnostically valuable information. Eg symptoms going back three months, say, will not be caused by an acute condition.
  6. Symptoms Make sure that the patient has removed clothing to be able to show you on his/ her skin where the pain etc is felt.

Do not accept the patient pointing to his/ her clothing. Take time to identify the symptoms that point to a specific organ or a specific disease. Pain is of huge value in making progress towards a diagnosis.

No gain without pain!

Diagnosis - diagnosis - diagnosis

At this point you will have enough information to make, not one but, three provisional diagnoses. Yes! Really! This is, in fact, how you solve problems anywhere.

Elementary my dear watson!

(with apologies to sherlock holmes)

For some reason it is often overlooked in medicine.

Eg. A 20 year old female caucasian student gives a 24 hour history of right iliac fossa pain.

Three reasonable working diagnoses.

  1. Ovarian bleed
  2. Appendicitis
  3. Ectopic pregnancy

Next Explore other symptoms to focus on each diagnosis. The three diagnoses may need to be changed as you gather more information.

Eg The patient has had central abdominal (midgut) colic before the pain 
      settled in the right iliac fossa?
                     1 Appendicitis
                     2 Acute ileitis
                     3 Mesenteric ileitis

On examination, look for signs to support/ exclude each diagnosis.

Eg There is tenderness in the pouch of Douglas.

                    1 Pelvic appendicitis
                    2 Ovarian cyst
                    3 Ectopic pregnancy

Arrange special tests to support/ exclude these diagnoses.

Eg Ultrasound shows a mass in the pouch of Douglas with a normal right ovary and tube.

                   1 Pelvic appendicitis.
                   2 Salpingitis
                   3 Broad ligament hernia

The final diagnosis will be confirmed at operation.

Message Simple use of symptoms and signs is a most powerful means to ordering the correct special test(s) and to getting the diagnosis.

(the process here is based on the work of tim de dombal and david leaper, who pioneered computer aided diagnosis of the acute abdomen based on boolean statistics).