A novel influenza a (H1N1) virus as a possible cause of pityriasis rosea?

Does influenza subtype H1N1 have a place in the etiology of pityriasis rosea?

Introduction

Pityriasis rosea (PR) is an acute, inflammatory skin disease of unknown cause. Various infectious agents including viruses have been proposed as causative agents and presence of influenza subtype H1N1 was shown in case reports with PR, but the relation was not conclusive. We hypothesited that there may be a relation between PR and H1N1, since both of them are prevalent in the same period as winter or season transitions.

Aim

To investigate the effect of the H1N1 virus in PR in this study.

Material and methods

Twenty-one female and 12 male PR patients who applied to Kırıkkale University Faculty of Medicine Hospital Dermatology Outpatient Clinic were included in the study. Influenza subtype H1N1 IgM and IgG antibodies were detected by enzyme immunoassay (EIA) in sera of patients; tissue biopsy specimens were examined for influenza subtype H1N1 RNA by PCR.

Results

Seven (23%) of the 33 patients had positive IgM and IgG antibodies. Influenza subtype H1N1 RNA was not detected in the tissue samples of 33 PR patients.

Conclusions

According to the results of this study, we can say that influenza subtype H1N1 does not play a role in PR etiology.

New Onset Guttate Psoriasis Following Pandemic H1N1 Influenza Vaccination

Since the introduction of H1N1 influenza vaccine in the wake of the 2009 H1N1 pandemic, many serious and non-serious vaccine-related adverse events have been reported. The vaccination could induce pain, erythema, tenderness, and induration on injected areas. These symptoms usually disappear in a few days after the vaccination. In this case, we observed a 26-year-old woman with multiple erythematous scaly macules scattered on the extremities and trunk. She was injected with an inactivated split-virus influenza A/H1N1 vaccine without adjuvant (Greenflu-S®, Green Corp.) on her left deltoid area 10 days earlier. The first lesion appeared on the injection site three days after the vaccination, and the following lesions spread to the trunk and extremities after a few days. Histopathological examinations showed neutrophilic collections within the parakeratotic cornified layer, moderate acanthosis, diminished granular layer, elongation and edema of the dermal papillae, and dilated capillaries. The lesions were successfully treated with topical steroids and ultraviolet B phototherapy within three weeks, and there was no relapse for the following fourteen months. We assumed that pandemic vaccination was an important trigger for the onset of guttate psoriasis in this case.