A 41-year-old man comes to the Emergency Department for three days of swelling and pain in the right knee, with functional impotence and fever Two weeks earlier he had had a self-limited diarrhea. On examination there is joint effusion, so we proceed to perform an arthrocentesis and obtain 50 cc of cloudy fluid, with decreased viscosity and the following analytical parameters: leukocytes 40. 000/microL (85% neutrophils), glucose 40 mg/dL, absence of crystals, Gram stain: no microorganisms are observed. Which of the following statements about this patient is 'CORRECT:
Gram negative does NOT rule out infection. We mark four.
Treatment with cloxacillin and ceftriaxone should be initiated pending the result of the fluid culture.
It is advisable to perform daily arthrocentesis to relieve symptoms and avoid joint destruction.
If the culture is negative, it is probably reactive arthritis.
The negativity of the Gram stain rules out septic arthritis.
Gram negative does NOT rule out infection.