Categorization	White blood cell count	Polymorphonuclear neutrophilic leukocytes	Examples
Normal	0 to 200 per mm3 (0 to 0.2 × 109 per L)	< 25% (0.25)	—
Noninflammatory	< 2,000 per mm3 (2 × 109 per L)	< 25% (0.25)	Osteoarthritis, internal derangement, myxedema
Inflammatory	2,000 to 50,000 per mm3 (2 to 50 × 109 per L)	>75% (0.75)	Rheumatoid arthritis, psoriatic arthritis, gout, pseudogout, Neisseria gonorrhoeae infection
Septic	> 50,000 per mm3 (50 × 109 per L); usually > 100,000 per mm3 (100 × 109 per L)	Usually > 90% (0.90)	Septic arthritis (primary concern); occasionally, gout, pseudogout, reactive arthritis, Lyme disease