The rise of staphylococcal super antigens in psoriatic patients: a case-control study

Staphylococcus aureus, the major virulence factor of hospital and community acquired infections, secretes numerous exotoxins (super antigens), which may affect immunological and inflammatory status in psoriatic skin lesion.

This study is designed to compare the S. aureus super antigens level in sera of psoriatic patients with normal cases (nevus).

A case control study was performed in dermatology ward of Rasoul Hospital in Tehran, IR Iran (2008 - 2010). Staphylococcal super antigens (Entrotoxin A, B, D and TSST1) were measured in serum of 41 psoriatic patients and 28 normal persons (Nevus) by ELISA. Chi square values (CI 95%, P value < 0.05) were calculated for all categorical variables.

In this study 63.4% (26) of cases were male, 36.6% (15) were female. Age ranged from 4 months to 64 years old, with a mean age of 33.7 ± 15.4 years. Type of skin disease in cases: 20% (8) were inflicted by the Gutate form of the disease; 59% (23) with chronic plaque psoriasis (CPP), 7.7% (3) with erythrodermic and 12.8% (5) had other types of the disease (plaque, pustular, inverse). TSST (toxic shock syndrome toxin) was detected in 47% (20/41) of cases and in 6% (1/28) of the controls with a significant difference. (P value = 0.000) Entrotoxins (A, B, D) were detected in the sera of 48.8% (21/41) of cases; and only 6 %( 1/21) of controls, showed significant differences (P value = 0.000) positive TSST was more common in spring, and correlates with CPP type of psoriasis, but not related to patient`s gender and age.

In this study, S. aureus were 25 times more in psoriatic patients. Super antigens should be first detected in the serum samples; if negative, the skin lesions should be examined by PCR especially in chronic types of disease. Adding the antibiotics against S. aureus to other conventional treatments might be helpful. It has a more important and significant role in children with acuteinfection.