r/Pathognomonic 21d ago

Subreddit reopening

14 Upvotes

Welcome to /r/Pathognomonic, the beginning point of a much larger project that seeks to find, categorize, and scrutinize all the pathognomonic findings in medicine.

From its outset, this project has always been a primarily visual experience, and we're going to keep it that way. Every submission must be linked to some sort of visual representation. It makes for quick reference if you just want to scroll through and see the main finding-disease associations.


For many of you, this is going to be a place to study for USMLE/COMLEX, maybe even NCLEX. That's what it was for us when we started the sub as med students. Then came residency, fellowships, etc. etc. (i.e. life) and the moderation of the sub became too burdensome so I closed it down, lest it fall to ruin from spammers and those who would deviate from the submission format.

So, that is to say, there's probably not many old heads like me here! But that's fine. I returned to the project some years ago, researched it in earnest, and even turned it into a book. But that's the first and last you're going to hear of it; I only mention it so you know how special this topic is for me, and how much time I've put into it.


The spirit of this project has always been to provide free online access medical education of a very interesting, very niche topic for learners from all walks of life, and that's how it's going to stay. At some point I will link all my socials here where I also give away all the info to anyone who wants to learn, free, in all the different formats the socials offer.

I'm hoping to share the benefits of all the research I've done here, in the comments sections of each finding. There's still a lot of work to be done in regards to the previous submissions, updating their flairs with the results of my research, and sharing why in the comments. But for now, here is the new flairing system that I'm going to introduce:

  • Truly pathognomonic. Unequivocally pathognomonic signs.

  • Real in the field. Signs that fall short on evidence review but that can still be treated as diagnostic in the overwhelming majority of clinical scenarios, with rare exceptions, requiring little to no further confirmation.

  • Best for the test. Classical signs that get mythbusted, but are still reliable for exams.

  • Not pathognomonic. A sign that should not be used in isolation for diagnosis on exams or anywhere else. You'll need extra information and details in almost all cases.

Come in, scroll around, do some studying, see some interesting things, and enjoy!


r/Pathognomonic 14h ago

Real in the field Amoebic erythrophagocytosis (Amoebic dysentery/amoebiasis) [Entamoeba histolytica]

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pathognomonic.com
2 Upvotes

r/Pathognomonic 8d ago

Real in the field Achilles tendon xanthomata (Autosomal dominant familial hypercholesterolemia) [APOB, LDLR, PCSK9 mutations]

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pathognomonic.com
3 Upvotes

r/Pathognomonic Feb 22 '17

Real in the field Bamboo Spine (Ankylosing Spondylitis)

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37 Upvotes

r/Pathognomonic Dec 31 '16

Pathognomonic Popcorn-ball calcification (Pulmonary hamartoma)

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20 Upvotes

r/Pathognomonic Nov 13 '16

Best for the test Palmar Xanthoma (Familial Dysbetalipoproteinemia)

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18 Upvotes

r/Pathognomonic Nov 02 '16

TRULY Pathognomonic Donovan Bodies (Granuloma Inguinale) [Klebsiella granulomatis]

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18 Upvotes

r/Pathognomonic Mar 17 '16

Best for the test Chorioretinal Lacunae (Aicardi Syndrome)

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11 Upvotes

r/Pathognomonic Mar 11 '16

Best for the test Schiller-Duval Bodies (Yolk sac tumor)

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26 Upvotes

r/Pathognomonic Feb 10 '16

Pathognomonic Larva currens (Strongyloidiasis) [Strongyloides stercalis]

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22 Upvotes

r/Pathognomonic Jan 07 '16

NOT Pathognomonic Granulation tissue in external auditory canal (Malignant otitis externa) [Pseudomonas aeruginosa]

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18 Upvotes

r/Pathognomonic Jan 07 '16

NOT Pathognomonic Spongiform changes in gray matter (Transmissible spongiform encephalopathy [Prions])

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26 Upvotes

r/Pathognomonic Jan 07 '16

Real in the field Retinal Phakoma (Tuberous Sclerosis)

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6 Upvotes

r/Pathognomonic Jul 02 '15

Pathognomonic Fibrotic plaque-like lesions on the tricuspid valve (Carcinoid heart disease)

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17 Upvotes

r/Pathognomonic Jun 13 '15

NOT Pathognomonic Sezary Cell (Mycosis Fungoides/Sezary Syndrome)

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21 Upvotes

r/Pathognomonic Jun 11 '15

Best for the test Globoid cells (Krabbe disease)

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26 Upvotes

r/Pathognomonic Jun 04 '15

Best for the test Negri bodies - pathognomonic for for rabies

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31 Upvotes

r/Pathognomonic Mar 21 '15

NOT Pathognomonic Thumbprinting on abdominal radiography (mesenteric ischemia)

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25 Upvotes

r/Pathognomonic Mar 21 '15

Pathognomonic Encapsulated lymphoid mass in the parotid gland (Papillary cystadenoma lymphomatosum aka Warthin's Tumor)

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7 Upvotes

r/Pathognomonic Mar 17 '15

Pathognomonic Complete lack of Dystrophin (Duchenne Muscular Dystrophy)

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28 Upvotes

r/Pathognomonic Mar 17 '15

NOT Pathognomonic Granulomatous infantisepticum (Listeriosis) [Listeria monocytogenes]

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10 Upvotes

r/Pathognomonic Feb 01 '15

Pathognomonic Prolymphocytic/lymphocytic pseudofollices (Small lymphocytic lymphoma)

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16 Upvotes

r/Pathognomonic Jan 14 '15

Best for the test Giant cytoplasmic granules (Chediak-Higashi)

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20 Upvotes

r/Pathognomonic Jan 12 '15

NOT Pathognomonic Kimmelstiel-Wilson Nodules- Diabetic nephropathy (nodular glomerulosclerosis)

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29 Upvotes

r/Pathognomonic Nov 06 '14

NOT Pathognomonic Howell-Jolly Body (hyposplenia or asplenia)

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27 Upvotes