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Pertinent Negatives in patient note

18K views 6 replies 4 participants last post by  Rufusito 
#1 ·
The PN is really confusing to me.

What do they mean by including 'pertinent negatives' for the differential. These have to support your differential.

Do they mean negative findings that make this dx likely (ex. no murphy sign which supports diagnosis of infectious gastroenteritis) or other findings that you would expect to support that diagnosis?

Any feedback is much appreciated!! : )
 
#2 ·
Patient with fever, vomiting, and headache. It's wise to mention that he had no neck stiffness, because meningitis should be on the top of your list in such constellation of symptoms.

The pertinent negatives are only mentioned in the HPI (history part), not under the suggested diagnosis.

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#3 · (Edited)
Thanks so much for your reply Sabio! : )

But what about the section where you have to support your differential diagnosis with 'History' and 'Physical'?
It says to mention pertinent negatives on the PN.

So for instance, if you have a patient with abdominal pain and you have
cholecystitis, peptic ulcer, and gastritis on your differential...how would you write the physical in the differential??

Like this?:

Cholecystitis
+ Murphys
colicky pain

peptic ulcer disease

Gastritis

See, for the peptic ulcer and gastritis, you're not going to find anything on the physical exam, so do we leave it blank?
 
#4 ·
Or let's say peptic ulcer is highest on our differential, followed by Gastritis and cholecystitis:

peptic ulcer
- Murphys
no colicky pain
no fever

Gastritis
- Murphys
no colicky pain

Cholecystitis


What negative pertinent physical findings can we put under cholecystitis?
 
#5 ·
I wouldn't sweat too much about negative findings in the differential because it's not logical, once you put a suggested differential then only you can mention the positive findings that would support that diagnosis, it does not make sense to mention negative findings while you are suggesting a diagnosis ( it makes sense only when you refute a diagnosis, something you can do in the HPI, not in the differential list).

So ignore the negative findings for the DDx, even if it is mentioned in the PN.

As for gastritis and PUD, the SP will usually give you some epigastric tenderness but nevertheless, if you have a diagnosis that has only history findings and no physical to support then it's absolutely OK, leave the physical findings blank. Do not fabricate physical signs that you have not tested for our that you did not find in the encounter (they'll consider it fatal mistake if you do).

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#7 ·
Regarding pertinent negatives:

Both pertinent positives and negatives should be included in the following ares of the patient note: (1) History, (2) Physical Examination, (3) The differential diagnosis (supporting evidence).

The history and physical exam is self-explanatory, the DDx may be more difficult to understand. Take bilateral joint pain of the MCP joints:
DDx 1: Osteoarthritis, pertinent positive - worsening pain with use, insidious onset; Pertinent negative - no constitutional symptoms, no swelling/warmness (also can be used on PE as pertinent negative when you palpate if not present-a pertinent negative).
DDx 2: Rheumatoid arthritis, pertinent positives- bilateral joint involvement, mother with SLE (or any rheumatological disease);; Pertinent negative - no involvement of DIPs (here, since osteoarthritis is high on differential, forget the order for now, relative to OA, this pertinent negative may make RA more likely ( in some cases, pertinent negatives may help a diagnosis be ruled in not by its relative nature to another differential but intrinsic to the disease itself, e.g. step throat, pertinent negative - no cough (which is actually one of the diagnostic criteria for strep... if esophagitis was the other on the differential, no cough is not justifying step throat relative to esophagitis (because cough is often absent from this diagnosis/does not lend much support even if present)-- thus, the absence of cough (a pertinent negative) instrinsically justifies strep throT (so 2 reasons for justifying a diagnosis based on a pertinent negative finding - as in the case above with OA, no fever justifies it RELATIVE to RA, of course assuming that is on the differential.....and in the case of strep, no cough supports this diagnosis intrinsically).

One last comment - I would think that more pertinent positives would be listed vs negatives--but keeping in mind an opportunity to list a negative will certainly make your diagnosis more likely. Some believe pertinent negatives are used to RULE OUT a diagnosis (e.g no tachycardia for PE, say after listing a bunch of positives) -- I do not believe this to be what they are asking.

Please refer to the USMLE website, which put out a pdf on the clarification of this point. These are my opinions and are not fact, refer to USMLE for definitive answers.
 
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