Potentially ambiguous question from GT - anyone's thoughts on this?

[Phloston]

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From GT:

"An 18-year-old female presents with a two day history of knee pain that tracks down to her ankle. She denies sustaining any trauma to her knee. She reports being sexually active. On examination, her knee is red, swollen and tender to palpation. Aspiration of her knee will likely show which of the following organisms?

A. Borrelia garinii
B. Staphylococcus aureus
C. Neisseria gonorrhea
D. Escherichia coli
E. Hemophilus influenzae

Answer Explanation

The correct answer is B.

The most common mistake to make with this question is to equivocate septic arthritis in a sexually active adult with an N. gonorrhea infection. Most adults (including 18-year-olds) are sexually active. Staphylococcus aureus is the most common cause of septic arthritis in adults. In other words, septic arthritis in a sexually active adult does not automatically indicate a gonorrheal infection.

Hemophilus influenzae was the most common cause of septic arthritis in children, but is now uncommon in areas where Hemophilus vaccination is practiced. Escherichia coli is found in the elderly, IV drug users and the seriously ill. Lyme disease, caused by Borrelia species, can manifest as a chronic, septic arthritis."

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P. 420 of FA2012 has the relevant info on septic arthritis.

I'm still a bit confused on this. Given this vignette/explanation, if I were to encounter this same question on the USMLE, I'd still feel N. gonorrhoea were the better answer.

I believe that if it had not been mentioned that she were sexually active and had asked for the most likely/common cause, S. aureus might be an okay answer, but explicit sexual activity points to Gonorrhoea as the better answer.

Any thoughts?

Cheers,

 

[ohyeahbaby]

From GT:

"An 18-year-old female presents with a two day history of knee pain that tracks down to her ankle. She denies sustaining any trauma to her knee. She reports being sexually active. On examination, her knee is red, swollen and tender to palpation. Aspiration of her knee will likely show which of the following organisms?

A. Borrelia garinii
B. Staphylococcus aureus
C. Neisseria gonorrhea
D. Escherichia coli
E. Hemophilus influenzae

Answer Explanation

The correct answer is B.

The most common mistake to make with this question is to equivocate septic arthritis in a sexually active adult with an N. gonorrhea infection. Most adults (including 18-year-olds) are sexually active. Staphylococcus aureus is the most common cause of septic arthritis in adults. In other words, septic arthritis in a sexually active adult does not automatically indicate a gonorrheal infection.

Hemophilus influenzae was the most common cause of septic arthritis in children, but is now uncommon in areas where Hemophilus vaccination is practiced. Escherichia coli is found in the elderly, IV drug users and the seriously ill. Lyme disease, caused by Borrelia species, can manifest as a chronic, septic arthritis."

-----


P. 420 of FA2012 has the relevant info on septic arthritis.

I'm still a bit confused on this. Given this vignette/explanation, if I were to encounter this same question on the USMLE, I'd still feel N. gonorrhoea were the better answer.

I believe that if it had not been mentioned that she were sexually active and had asked for the most likely/common cause, S. aureus might be an okay answer, but explicit sexual activity points to Gonorrhoea as the better answer.

Any thoughts?

Cheers,

word

I agree with you.

how would you even rewrite that vignette so that the answer would in fact be n. gonorrhoea if they are saying that even though they mentioned she is sexually active, it does not mean she is sexually active? 😱

 

[ohyeahbaby]

actually i just remembered i saw a practice question exactly like that where the answer was actually Neisseria gonorrhoeae. It was the same exact vignette, but it wasn't a girl - it was a dude, and they mentioned that it hurts when he pees.

so basically always assume it's staph, even if they are having sex. If they mention just one sx related to nisseria, then I would choose it as the answer.

 

[HelpPleaseMD]

Maybe gonnocal arjtiritis would be associated with more symptoms suggestive of a gonnocoal infection such as pain or burning on urination or lower abdominal pain. This is a really weird question though

I had a similar question on one of my school exams where the answer was Staph Aureus.

 

[Phloston]

I actually believe this question is a fluke. Given that sexual activity is explicitly mentioned, I would answer N. gonorrhoea with confidence if I were to see this on my future USMLE (i.e. I could imagine putting S. aureus on my real exam, then 24 hrs later being like, "wtf was I thinking?")

If they mentioned that she weren't sexually active or they had merely asked for the most common cause of septic arthritis, then S. aureus would be better.

I had a practice question on this some time ago (I have this info annotated into FA), where S. aureus is more common than S. epidermidis following prosthetic joint replacement, however. S. epidermidis is more common following prosthetic valve replacement.

The main point GT wants to drive is that, irrespective of sexual activity, S. aureus is more likely than N. gonorrhoea, but I think, in terms of learning to answer questions, if they mention sexual activity, it's because they want you to know the link.

 

[ohyeahbaby]

if they mention sexual activity, it's because they want you to know the link.

that's where I disagree. I see what you're saying. But it's been my experience that when they do mention something ******edly obvious, it's meant to mislead you. But again, I see what you're saying and I've definitely seen questions where they want you to see the link.

aureus is most common - this statistic is obviously taking into account the fact that people like to do each other. So if you get someone who has septic arthritis and that patient tells you they're doing someone else - that shouldn't change your judgment, since that's already been taken into account.

 

[illegallysmooth]

I actually believe this question is a fluke. Given that sexual activity is explicitly mentioned, I would answer N. gonorrhoea with confidence if I were to see this on my future USMLE (i.e. I could imagine putting S. aureus on my real exam, then 24 hrs later being like, "wtf was I thinking?")

If they mentioned that she weren't sexually active or they had merely asked for the most common cause of septic arthritis, then S. aureus would be better.

I had a practice question on this some time ago (I have this info annotated into FA), where S. aureus is more common than S. epidermidis following prosthetic joint replacement, however. S. epidermidis is more common following prosthetic valve replacement.

The main point GT wants to drive is that, irrespective of sexual activity, S. aureus is more likely than N. gonorrhoea, but I think, in terms of learning to answer questions, if they mention sexual activity, it's because they want you to know the link.

So you agree that staph is a more common cause than neiserria, even among those doing the no-pants-dance, but you'd intentionally answer the question incorrectly if they include the pt's sexual activity? What if the patient is 60 and has been in a monogamous relationship with no history of STDs?

 

[Phloston]

If they mention sexual activity and then ask for the aspirate, the better answer is N. gonorrhoea. If they mention sexual activity but the actual question is, "what is the most common cause of septic arthritis?" The better answer would be S. aureus.

Therefore, S. aureus is the better answer if they ask specifically for the most common cause (irrespective of sexual activity) or if they mention lack of sexual activity or if they mention prosthetic joint replacement. If sexual activity is mentioned but the former or latter of the previous sentence is not mentioned, N. gonorrhoea is better.

 

[ijn]

I can't believe you're going to torture yourself with this kind of stuff for the next 8 months.

 

[illegallysmooth]

If they mention sexual activity and then ask for the aspirate, the better answer is N. gonorrhoea. If they mention sexual activity but the actual question is, "what is the most common cause of septic arthritis?" The better answer would be S. aureus.

Therefore, S. aureus is the better answer if they ask specifically for the most common cause (irrespective of sexual activity) or if they mention lack of sexual activity or if they mention prosthetic joint replacement. If sexual activity is mentioned but the former or latter of the previous sentence is not mentioned, N. gonorrhoea is better.

Ok then...

 

[ohyeahbaby]

Ok then...

 

[defcon8]

that's where I disagree. I see what you're saying. But it's been my experience that when they do mention something ******edly obvious, it's meant to mislead you. But again, I see what you're saying and I've definitely seen questions where they want you to see the link.

This is similar to giving you an hbss with osteomyelitis and asking the most likely pathogen then asking you to choose between salmonella and s. aureus. Even in the hbss subset, s. aureus is still the more common organism, but then are they simply asking you to make the link with salmonella

 

[HelpPleaseMD]

This is similar to giving you an hbss with osteomyelitis and asking the most likely pathogen then asking you to choose between salmonella and s. aureus. Even in the hbss subset, s. aureus is still the more common organism, but then are they simply asking you to make the link with salmonella

This is actually different. In the case you stated sallmonela is the most common cause because sickle cell patients have no spleen and they have trouble getting rid of the SHIN organisms. The other case the person could have been treated with ceftrixone.

 

[illegallysmooth]

This is actually different. In the case you stated sallmonela is the most common cause because sickle cell patients have no spleen and they have trouble getting rid of the SHIN organisms. The other case the person could have been treated with ceftrixone.

This is correct. In sickle cell, the most common is salmonella and other gram negatives. Staph only accounts for about 1/4 of osteomyelitis cases in sickle cell.

In the septic arthritis case, the most common cause is never neisseria, whether someone is sexually active or not.

According to UpToDate

Many pathogens are capable of causing bacterial arthritis (table 1). S. aureus (including MRSA) is the most common bacterium infecting adult joints [4,6,26]. Other gram-positive organisms such as streptococci are also frequent causes of septic arthritis. Septic arthritis due to gram-negative bacilli is generally observed in the setting of trauma, intravenous drug users, neonates, the elderly, and in association with underlying immunosuppression.
Gonococcal arthritis can present with an acute monoarthritis, although migratory polyarthritis and tenosynovitis are more typical. (See "Disseminated gonococcal infection.

 

[ohyeahbaby]

This is correct. In sickle cell, the most common is salmonella and other gram negatives. Staph only accounts for about 1/4 of osteomyelitis cases in sickle cell.

In the septic arthritis case, the most common cause is never neisseria, whether someone is sexually active or not.

According to UpToDate

Many pathogens are capable of causing bacterial arthritis (table 1). S. aureus (including MRSA) is the most common bacterium infecting adult joints [4,6,26]. Other gram-positive organisms such as streptococci are also frequent causes of septic arthritis. Septic arthritis due to gram-negative bacilli is generally observed in the setting of trauma, intravenous drug users, neonates, the elderly, and in association with underlying immunosuppression.
Gonococcal arthritis can present with an acute monoarthritis, although migratory polyarthritis and tenosynovitis are more typical. (See "Disseminated gonococcal infection.

thanks for looking that up!

 

[defcon8]

This is actually different. In the case you stated sallmonela is the most common cause because sickle cell patients have no spleen and they have trouble getting rid of the SHIN organisms. The other case the person could have been treated with ceftrixone.

There was a discussion on this before:
http://forums.studentdoctor.net/showthread.php?t=192710
Cant argue with the evidence though

 

[Phloston]

This is correct. In sickle cell, the most common is salmonella and other gram negatives. Staph only accounts for about 1/4 of osteomyelitis cases in sickle cell.

In the septic arthritis case, the most common cause is never neisseria, whether someone is sexually active or not.

According to UpToDate

Many pathogens are capable of causing bacterial arthritis (table 1). S. aureus (including MRSA) is the most common bacterium infecting adult joints [4,6,26]. Other gram-positive organisms such as streptococci are also frequent causes of septic arthritis. Septic arthritis due to gram-negative bacilli is generally observed in the setting of trauma, intravenous drug users, neonates, the elderly, and in association with underlying immunosuppression.
Gonococcal arthritis can present with an acute monoarthritis, although migratory polyarthritis and tenosynovitis are more typical. (See "Disseminated gonococcal infection.

That's a bold statement you've made, because it's wrong. How did you even draw that conclusion?

I went to PubMed, and per this article:

Rheumatol Int. 2008 Nov;29(1):81-5. Epub 2008 May 24.
Acute septic arthritis: remember gonorrhea.
Dalla Vestra M, Rettore C, Sartore P, Velo E, Sasset L, Chiesa G, Marcon L, Scarano L, Simioni N, Bacelle L, Patrassi GM.

Virtually every bacterial organism has been reported to cause
septic arthritis [1]. The microorganisms responsible for bacterial arthtritis are largely dependent on host factors. In fact,
the pathogenesis depends on the interaction of the host
immune response and the invading pathogen. The most common etiological agent of septic arthritis in adults in Europe is
Staphylococcus aureus. After S. aureus, Streptococcus spp.
are the next most commonly isolated bacteria from adult
patients with septic artrithis. Streptococcus pyogenes is usually the most common streptococcal isolate. Gram-negative
bacilli account for approximately 10–20% of cases. The most
common Gram-negative organisms are Pseudomonas aeruginosa and Escherichia coli [1–6]. Anaerobes are also isolated in a small subgroup of patients, usually in diabetic
patients or in patients with prosthetic joints. Approximately,
10% have polymicrobial infections. Septic arthritis may also
be caused by Shighella spp., Salmonella spp., Campylobacter
spp. and Yersinia spp. A rare form of migrating arthritis has
been described to be caused by Streptobacillus moniliformis.
In HIV-infected patients, S. aureus continues to be the most
common isolate; however, in these patients also opportunistic pathogens are often isolated including S. pneumoniae,
mycobacterial species and fungal species [7, 8]. In western
Europe, the number of cases of gonorrheae decreased by
about 70% in the last two decades and septic arthritis caused
by Neisseria gonorrhoeae is actually relatively rare [9].
However, recent reports demonstrated an increase in the rate
of gonococcal infection in the last few years, expecially in
men who have sex with men. These increased incidence rates
may result in larger number of gonococcal artrithis cases to
be observed. In the USA, with 339,593 gonorrhea cases
reported in 2005, gonorrhea is the second most common
communicable disease and N. gonorrhoea is the most common cause of septic arthritis [10]


----

Conclusion: on the USMLE, if they mention sexual activity and don't mention surgery/trauma, N. gonorrhoea is correct.

 

[defcon8]

That's a bold statement you've made, because it's wrong. How did you even draw that conclusion?

I went to PubMed, and per this article:

Rheumatol Int. 2008 Nov;29(1):81-5. Epub 2008 May 24.
Acute septic arthritis: remember gonorrhea.
Dalla Vestra M, Rettore C, Sartore P, Velo E, Sasset L, Chiesa G, Marcon L, Scarano L, Simioni N, Bacelle L, Patrassi GM.

Virtually every bacterial organism has been reported to cause
septic arthritis [1]. The microorganisms responsible for bacterial arthtritis are largely dependent on host factors. In fact,
the pathogenesis depends on the interaction of the host
immune response and the invading pathogen. The most common etiological agent of septic arthritis in adults in Europe is
Staphylococcus aureus. After S. aureus, Streptococcus spp.
are the next most commonly isolated bacteria from adult
patients with septic artrithis. Streptococcus pyogenes is usually the most common streptococcal isolate. Gram-negative
bacilli account for approximately 10–20% of cases. The most
common Gram-negative organisms are Pseudomonas aeruginosa and Escherichia coli [1–6]. Anaerobes are also isolated in a small subgroup of patients, usually in diabetic
patients or in patients with prosthetic joints. Approximately,
10% have polymicrobial infections. Septic arthritis may also
be caused by Shighella spp., Salmonella spp., Campylobacter
spp. and Yersinia spp. A rare form of migrating arthritis has
been described to be caused by Streptobacillus moniliformis.
In HIV-infected patients, S. aureus continues to be the most
common isolate; however, in these patients also opportunistic pathogens are often isolated including S. pneumoniae,
mycobacterial species and fungal species [7, 8]. In western
Europe, the number of cases of gonorrheae decreased by
about 70% in the last two decades and septic arthritis caused
by Neisseria gonorrhoeae is actually relatively rare [9].
However, recent reports demonstrated an increase in the rate
of gonococcal infection in the last few years, expecially in
men who have sex with men. These increased incidence rates
may result in larger number of gonococcal artrithis cases to
be observed. In the USA, with 339,593 gonorrhea cases
reported in 2005, gonorrhea is the second most common
communicable disease and N. gonorrhoea is the most common cause of septic arthritis [10]


----

Conclusion: on the USMLE, if they mention sexual activity and don't mention surgery/trauma, N. gonorrhoea is correct.

I will further support this..:

Uptodate states: "Gonococcal infection — Disseminated gonococcal infection (DGI) is the most common cause of acute nontraumatic monoarthritis or oligoarthritis in young adults."
(Article - Evaluation of the adult with monoarticular pain)

PubMed
TIMonarthritis: differential diagnosis.
AUSack K
SOAm J Med. 1997;102(1A):30S.

Acute monarthritis should be regarded as infectious until proved otherwise. Early evaluation is crucial because of the capacity of some infectious agents to destroy cartilage rapidly. The history and physical examination can provide highly suggestive clues, but a definitive diagnosis may depend on arthrocentesis and analysis of synovial fluid. The diagnosis of acute monarthritis is rarely established by radiography. The most common cause of bacterial arthritis is Neisseria gonorrhoeae. Staphylococcus aureus and streptococci are the organisms most frequently implicated in nongonococcal bacterial arthritis, although the possibility of Gram-negative bacteria or anaerobes should not be overlooked in intravenous drug users or immunocompromised patients. Inflammation in a large joint, particularly the knee, might arouse suspicion of Lyme disease. Other, less frequently encountered infectious causes of acute monarthritis include tuberculosis and other mycobacteria, fungi, and viruses. Arthroscopic examination and synovial tissue biopsy may be necessary to diagnose such processes. Microscopic examination of the synovial fluid may reveal a crystalline etiology for monarthritis. Monosodium urate crystals induce gout, usually in the toe, ankle, or midfoot, while calcium pyrophosphate crystals cause pseudogout, most often in the knee or wrist. Acute monarthritis is sometimes a manifestation of osteoarthritis or an early sign of a systemic arthritis such as rheumatoid or reactive arthritis. Processes underlying acute monarthritis can also evolve into a more chronic clinical picture as exemplified by the spondyloarthropathies.
ADDepartment of Medicine, University of California, San Francisco 94143-0326, USA.
PMID9217557

 

[illegallysmooth]

That's a bold statement you've made, because it's wrong. How did you even draw that conclusion?

I went to PubMed, and per this article:

Rheumatol Int. 2008 Nov;29(1):81-5. Epub 2008 May 24.
Acute septic arthritis: remember gonorrhea.
Dalla Vestra M, Rettore C, Sartore P, Velo E, Sasset L, Chiesa G, Marcon L, Scarano L, Simioni N, Bacelle L, Patrassi GM.

Virtually every bacterial organism has been reported to cause
septic arthritis [1]. The microorganisms responsible for bacterial arthtritis are largely dependent on host factors. In fact,
the pathogenesis depends on the interaction of the host
immune response and the invading pathogen. The most common etiological agent of septic arthritis in adults in Europe is
Staphylococcus aureus. After S. aureus, Streptococcus spp.
are the next most commonly isolated bacteria from adult
patients with septic artrithis. Streptococcus pyogenes is usually the most common streptococcal isolate. Gram-negative
bacilli account for approximately 10–20% of cases. The most
common Gram-negative organisms are Pseudomonas aeruginosa and Escherichia coli [1–6]. Anaerobes are also isolated in a small subgroup of patients, usually in diabetic
patients or in patients with prosthetic joints. Approximately,
10% have polymicrobial infections. Septic arthritis may also
be caused by Shighella spp., Salmonella spp., Campylobacter
spp. and Yersinia spp. A rare form of migrating arthritis has
been described to be caused by Streptobacillus moniliformis.
In HIV-infected patients, S. aureus continues to be the most
common isolate; however, in these patients also opportunistic pathogens are often isolated including S. pneumoniae,
mycobacterial species and fungal species [7, 8]. In western
Europe, the number of cases of gonorrheae decreased by
about 70% in the last two decades and septic arthritis caused
by Neisseria gonorrhoeae is actually relatively rare [9].
However, recent reports demonstrated an increase in the rate
of gonococcal infection in the last few years, expecially in
men who have sex with men. These increased incidence rates
may result in larger number of gonococcal artrithis cases to
be observed. In the USA, with 339,593 gonorrhea cases
reported in 2005, gonorrhea is the second most common
communicable disease and N. gonorrhoea is the most common cause of septic arthritis [10]


----

Conclusion: on the USMLE, if they mention sexual activity and don't mention surgery/trauma, N. gonorrhoea is correct.

I was talking about septic arthritis period, because that's the question that was asked - which is the most common pathogen in septic arthritis, period. I drew that conclusion by reading UpToDate, which is, well... up to date. In the absence of other specific factors, staph is the most common bacterium infecting adult joints. If you then want to give a different age range, eliminate factors like trauma, prosthesis, etc, you could surely come up with a population in which neisseria will be most common.

Why did you bother making this post if your heels are dug in and you're going to be an argumentative tool about it? If you just want to post to broadcast your opinion, fine, cool, but don't bother asking for other people's opinions then.


These are the refs for that-
4
PubMed
TISeptic arthritis: current diagnostic and therapeutic algorithm.
AUMathews CJ, Coakley G
SOCurr Opin Rheumatol. 2008;20(4):457.

ADDepartment of Rheumatology, Queen Elizabeth Hospital NHS Trust, Stadium Road, Woolwich, London, UK. [email protected]
PMID18525361
6
PubMed
TIBacterial arthritis.
AUGoldenberg DL, Reed JI
SON Engl J Med. 1985;312(12):764.

AD
PMID3883171
26
PubMed
TIHow common is MRSA in adult septic arthritis?
AUFrazee BW, Fee C, Lambert L
SOAnn Emerg Med. 2009;54(5):695.

 

[Phloston]

I wouldn't say I'm argumentative. I'm just debating. If you heard my voice, I'm actually thankful for your input regardless.

 

[illegallysmooth]

I wouldn't say I'm argumentative. I'm just debating. If you heard my voice, I'm actually thankful for your input regardless.

Ok then. Sorry for calling you a tool.

 

[defcon8]

I was talking about septic arthritis period, because that's the question that was asked - which is the most common pathogen in septic arthritis, period. I drew that conclusion by reading UpToDate, which is, well... up to date. In the absence of other specific factors, staph is the most common bacterium infecting adult joints. If you then want to give a different age range, eliminate factors like trauma, prosthesis, etc, you could surely come up with a population in which neisseria will be most common.

Why did you bother making this post if your heels are dug in and you're going to be an argumentative tool about it? If you just want to post to broadcast your opinion, fine, cool, but don't bother asking for other people's opinions then.


These are the refs for that-
4
PubMed
TISeptic arthritis: current diagnostic and therapeutic algorithm.
AUMathews CJ, Coakley G
SOCurr Opin Rheumatol. 2008;20(4):457.

ADDepartment of Rheumatology, Queen Elizabeth Hospital NHS Trust, Stadium Road, Woolwich, London, UK. [email protected]
PMID18525361
6
PubMed
TIBacterial arthritis.
AUGoldenberg DL, Reed JI
SON Engl J Med. 1985;312(12):764.

AD
PMID3883171
26
PubMed
TIHow common is MRSA in adult septic arthritis?
AUFrazee BW, Fee C, Lambert L
SOAnn Emerg Med. 2009;54(5):695.

From GT:

"An 18-year-old female presents with a two day history of knee pain that tracks down to her ankle. She denies sustaining any trauma to her knee. She reports being sexually active. On examination, her knee is red, swollen and tender to palpation. Aspiration of her knee will likely show which of the following organisms?

A. Borrelia garinii
B. Staphylococcus aureus
C. Neisseria gonorrhea
D. Escherichia coli
E. Hemophilus influenzae

Answer Explanation

The correct answer is B.

Ok lets all calm down.. take home message.. young adult who is sexually active with no history of trauma.. most likely cause of septic arthritis is gonococcus 🙂

 

[Phloston]

Ok lets all calm down.. take home message.. young adult who is sexually active with no history of trauma.. most likely cause of septic arthritis is gonococcus 🙂

For some reason I had read this as young adult who is sexually attractive with no history of trauma, and was like wtf. 🙂

 

[ohyeahbaby]

I get where everyone is coming from. However, for me, if it only mentions that there's sexual activity, then I will put staph aureus, and I will assume that they are using protection. If it mentions sexual activity AND there's a gonorrhea sx, I would put gonorrhea.

If it mentions sexual activity AND it says they are not using protection, without giving us any other information, then I don't know what I would put honestly. But between Uworld, USMLErx and the random questions I've found online, I've come across at least 5 or 6 of these questions. I've never gotten them wrong because usually everything you need is in there.

 

[defcon8]

For some reason I had read this as young adult who is sexually attractive with no history of trauma, and was like wtf. 🙂

 

[BlueArc]

That's a bold statement you've made, because it's wrong. How did you even draw that conclusion?

Conclusion: on the USMLE, if they mention sexual activity and don't mention surgery/trauma, N. gonorrhoea is correct.

Hey phloston you're still sticking to this?

 

[Phloston]

Hey phloston you're still sticking to this?

Yeah. If they specifically mention the patient is sexually active, the answer is N. gonorrhea.

 

[madchemist89]

The answer has been changed to Neisseria gonorrhea.

 

[Ionian]

Came across a similar Rx question.
24 year old male.
Denies trauma.
Knee pain, knee appears red, warm and swollen, with no signs of scratches or trauma.

Answer. Gonorrhea.

Answer says hes at the right age to be sexually active, wasn't even part of the question.

But I'm still wondering why this was in issue?
Without external trauma, why were people assuming he has an infection with skin flora?

 

[notbobtrustme]

Came across a similar Rx question.
24 year old male.
Denies trauma.
Knee pain, knee appears red, warm and swollen, with no signs of scratches or trauma.

Answer. Gonorrhea.

Answer says hes at the right age to be sexually active, wasn't even part of the question.

But I'm still wondering why this was in issue?
Without external trauma, why were people assuming he has an infection with skin flora?

you don't need external trauma for S. aureus, although osteomyelitis usually follows trauma.

The reason everyone hates on that question is because the pt has no risk factors for N. gonorrhea osteomyelitis and the #1 cause (both in sexually and non-sexually active persons) is S. aureus. The question is a poor test of knowledge for that reason.

 

[Ionian]

you don't need external trauma for S. aureus, although osteomyelitis usually follows trauma.

The reason everyone hates on that question is because the pt has no risk factors for N. gonorrhea osteomyelitis and the #1 cause (both in sexually and non-sexually active persons) is S. aureus. The question is a poor test of knowledge for that reason.

Huh? I believe we are talking septic arthritis here, again why I don't understand the problem?

I've always had it down:
Osteomyelitis: #1 Staph aureus, #2 Gonorrhea
Septic arthritis: #1 Gonorrhea #2 Staph aureus (thus where's the confusion? who is saying its staph? Again as I said, the Rx question didn't mention sexual history at all and that was still the answer so I guess I agree with the OP, yes.... Gonorrhea)

idk