Acute Guttate Psoriasis Patients Have Positive Streptococcus Hemolyticus Throat Cultures and Elevated Antistreptococcal M6 Protein Titers

Abstract

To further study the role of Streptococci hemolyticus infection and streptococcal M6 protein in the pathogenesis of acute guttate psoriasis, streptococcal cultures were taken from the throats of 68 patients with acute guttate psoriasis. PCR technique was applied to detect M6 protein encoding DNA from those cultured streptococci. Pure M6 protein was obtained by Sephacry/S-200HR and Mono-Q chromatography from proliferated Streptococcus hemolyticus. Antistreptococcal M6 protein titers were measured in the serum of patients with acute guttate psoriasis, plaque psoriasis and healthy controls by ELISA. A high incidence of Streptococcus hemolyticus culture was observed in the guttate psoriatic group compared with the plaque psoriasis and control groups. Fourteen strains of Streptococcus hemolyticus were cultured from the throats of 68 acute guttate psoriasis patients. Of these, 5 strains contain DNA encoding the M6 protein gene as confirmed by PCR technique. More than 85% purification of M6 protein was obtained from Streptococcus pyogenes. Applying our pure M6 protein with the ELISA methods, we found that the titer of antistreptococcal M6 protein was significantly higher in the serum of guttate psoriasis patients than in the control or plaque psoriasis groups (P < 0.01). We verified that patients of acute guttate psoriasis have a high incidence of Streptococcus hemolyticus in their throats and raised titers of antistreptococcal M6 protein in their sera.

Allergic skin diseases

“…T cells in both diseases are triggered by conventional antigens and superantigens. Some studies suggest that group A streptococcus is a superantigen for acute guttate psoriasis, which is often preceded by or concurrent with infection 37,38 and is associated with an increase in serum antistreptococcal titers. Symptoms in patients with guttate psoriasis and AD frequently improve with systemic antibiotic therapy.…”

Psoriasis: epidemiology, natural history, and differential diagnosis

“…36,37 Streptococcal infections are often triggers of guttate psoriasis, especially in children and young adults. 38 Human immunodeficiency virus (HIV) has been associated with the onset of severe plaque psoriasis which is often non-responsive to standard treatment. Medications, including beta-blockers, lithium, antimalarials, tetracycline antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), and steroid withdrawal have been associated with the onset or exacerbation of psoriasis, mostly based in case reports.…”

Clinical comparison of psoriasis in Korean adults and children: correlation with serum anti-streptolysin O titers

“…The ASO response is usually elevated following a streptococcal respiratory tract infection. Patients with acute guttate psoriasis have a high incidence of Streptococcus hemolyticus isolated from their throats and raised titers of antistreptococcal M6 protein in their sera [26]. Also, 20-30% of patients with chronic plaque psoriasis had positive throat cultures for hemolytic streptococci, and 25-30% had raised ASO titers [22].…”