Antistreptolysin O titre (ASO or ASLO) is the measure of the rate of antibodies processed by the body after contact with streptolysin O produced by streptococcus.
It is the serological test used for the diagnosis of beta-haemolytic Streptococcus type A infection.
The titre becomes positive one week after infection, reaches its peak after about 3-5 weeks, then decreases in the following months.
The titer expresses an ongoing or past antibody response evoked by a series of antigens present in beta-haemolytic Streptococcus type A.
v.n. < 200 Ul
Streptococcal infections (rhinitis, pharyngitis, tonsillitis, otitis, sinusitis, impetigo contagiosa, tooth granuloma, paronychia)
Acute articular rheumatism
Primary chronic polyarteritis