Infective arthritis
Bacterial infection  (Acute suppurative arthritis)
                                Staphylococcus aureus
  Streptococcus pyogenes
Diplococcus pneumoniae
Neisseria gonorrhease
Haemophilus influenzae
Gram-negative organism
Borrelia burdorferi (Lyme Disease)
Mycobacterium tuberculosis (Tuberculous arthritis)
 
Virus-associated arthritis
Fungal arthritis (rare)