Sero-prevalence of anti-streptolysin ‘O’ antibodies at tertiary care hospital: A two year of prospective study

Streptococcus pyogenes (Group A Streptococcus/GAS) is the most prevalent human bacterial pathogens amongst streptocoocus species. It causes a wide range of suppurative infections in the respiratory tract and skin, life-threatening soft tissue infections, and certain types of toxin associated reactions. Some of these infections may, in addition, result in severe non-suppurative sequelae due to adverse immunological reactions induced by the infecting streptococci. As the diagnosis of non-suppurative infection caused Streptococcus pyogenes is only depends on immunological reaction, present study was carried out to see the sero-prevalence of Anti-streptolysin O antibodies in our region.

In the present prospective study was carried out in the Department of Microbiology under serology section at a tertiary care hospital from January 2015 to December 2016. Blood samples were taken from clinical suspicion cases of streptococcal infection. All samples were tested by using qualitative and semi-quantitative antibody detection method as per the standard guidelines.

A total of 1526 blood samples were collected and processed for the detection anti-streptolysin O antibodies. Out of which 92 (6.03%) were positive for ASO, among them 59 were from out door-patients department and 33 were from indoor-patients department. Out of 92 positive cases, 48 were males and 44 were female patients. Highest positive cases were found in the age group of 11–20 years (7.15), followed by the age group of 21–30 years where the prevalence was found to be 6.40%.

The presence of elevated streptococcal antibody titers in such population, which probably reflects a high background prevalence of streptococcal infections, should be taken into consideration when evaluating the role of the group A streptococcus in non-purulent complications of infections.