HLA-Cw6 homozygosity in plaque psoriasis is associated with streptococcal throat infections and pronounced improvement after tonsillectomy: A prospective case series

Abstract

Background Carriage of the HLA-Cw*0602 allele is associated with a particular set of clinical features and treatment responses in psoriasis. Tonsillectomy can improve psoriasis. Objectives To evaluate whether HLA-Cw*0602 predicts a favourable outcome after tonsillectomy of psoriasis patients. Methods This prospective case series followed 28 tonsillectomized patients with plaque psoriasis for 24 months. The Psoriasis Area and Severity Index (PASI), the Psoriasis Disability Index (PDI) and the Psoriasis Life Stress Inventory (PLSI) were used for assessment. Tonsils were swabbed for bacteria and patients genotyped for HLA-Cw*0602. Results After tonsillectomy, HLA-Cw*0602 homozygotes showed significantly more improvement, compared with heterozygous and HLA-Cw*0602 negative patients. Thus, PASI was reduced by 82% in the homozygous patients compared with 42% and 31% respectively (P < .001), PDI improved by 87% compared with 38% and 41% respectively (P < .001) and PLSI was 82% reduced compared with 60% and 54% respectively (P < .001). The homozygotes had more often psoriasis onset associated with a throat infection (P = .007) and an increased frequency of streptococcal throat infections per lifetime (P = .038). Limitations Few patients were included and some data was retrospective. Conclusions Homozygous HLA-Cw*0602 carriage in plaque psoriasis may predict a favourable outcome after tonsillectomy.

The Psoriasis Risk Allele HLA-C*06:02 Shows Evidence of Association with Chronic or Recurrent Streptococcal Tonsillitis

“…As shown by others, the presence of the HLA-C*06:02 allele not only affects the frequency of the bacterial load in asymptomatic individuals but also, as seen in our clinical study population (Table 3), correlates with a clinical tonsillar disease (18). A prospective study of 28 tonsillectomy patients also points to association of HLA-C*06:02 with streptococcal throat infections and suggests that the degree of clinical improvement after tonsillectomy is associated with HLA-C*06:02 homozygocity (32). The finding that psoriasis and streptococcal tonsillitis share the same risk allele is not unexpected, because streptococcal M protein is known to induce activation of the skin-homing CLA ϩ CD8 ϩ T cells that are found in psoriasis skin lesions at high frequencies (25).…”

HLA-Cw6 and psoriasis

“…A case–control study also indicated that the prevalence of positive streptococcal throat swabs for HLA‐Cw6 ‐positive patients was twice that of HLA‐Cw6 ‐negative patients, regardless of disease phenotype . In addition, homozygous HLA‐Cw6 ‐positive patients experienced significantly more streptococcal pharyngitis per lifetime and were more likely to have psoriasis onset associated with a throat infection . Interestingly, homozygotes showed drastic improvements after tonsillectomy vs. heterozygotes and HLA‐Cw6 ‐negative patients.…”

Environmental risk factors and epigenetic alternations in psoriasis

“…Another infectious factor is Sptreprococcus in the tonsils. It is commonly known, that many upper airway tract infections may intensify psoriatic lesions [65,66,67].…”

“…Impairing work of the immune system occurs as an imbalance between the mutual microenvironment of microbiota and immune cells, which allows pathogens to extend and lead to infection [73]. On the other hand, this stimulates the immune system's reaction and usually occurs as an exacerbation, or even provokes the onset of psoriasis [65,66,67].…”