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55 yo man with monoarthritis of knee joint

3450 Views 7 Replies 4 Participants Last post by  tkourkou
A 55 yo man comes to the ED complaining for recent onset pain in his right knee. This incident happened 2 days after he returned home after an all day long golf game during a hot summer day, followed by meat and beer consumption. Examination reveals a hot, red and swollen knee joint with limited mobility. Examination of the joint fluid has the following characteristics:
-Negative birefringent crystals phagocytosed by leucocytes
-Few red cells
-55,000 WBCs
At which should you aim your treatment?

a) Gout
b) Pseudogout
c) Septic arthritis
d) Medial collateral ligament tear
e) Dehydration
f) Counseling on the dangers of increased sun exposure
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I would also think gout - reasons being the negatively birefringent crystals, and the history of beer consumption alongwith the knee joint being affected which is the second most common form.

however, acutely hot joint - with a high WBC count and without any culture certainly in a younger male would be confusing for septic arthritis.... specially if the golf game was replaced by a beer party in a singles club :D
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Thank you guys for the replies!:happy::happy::happy::happy::happy:

The purpose of the question is to stress out the importance of WBC numbers in the differential diagnosis of acute monoarthritides. Whilst 2,000-50,000 cells indicate an inflammatory condition, any value above 50,000 is highly indicative of a septic arthritis. It is important to know that gouty flares and septic arthritides can often coexist, as in this patient! The question, cleverly asks about to which condition should you aim your treatment, which is septic arthritis, due to the highly destructive and debilitating nature of the disease. It is better to empirically treat this condition until the culture results show the clear nature of the underlying illness.

Another important issue here is the presence of INTRA-CELLULAR crystals which are more indicative of a gouty flare. If the crystals are EXTRA-CELLULARLY it drives us away from the possibility of an acute gouty flare.
great question thanks - i was thinking the same thing with 50,000 WBC count - the magic number in kaplan.. but didnt know that it would coexist... interesting indeed.
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