Pityriasis rosea of Gibert: immunological aspects

Coronavirus disease 2019 and pityriasis rosea: A review of the immunological connection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterized by the activation of a cytokine storm derived from an excess release of cytokine (interleukin [IL]-6, interferon [IFN] I, C-X-C motif chemokine ligand [CXCL]10, tumor necrosis factor [TNF]-α, macrophage inflammatory protein [MIP]1) due to an uncontrolled immune activation. There has been a fivefold increase in the number of cases of pityriasis rosea during the SARS-CoV-2 pandemic. Using the keywords "pityriasis" and "COVID-19", we carried out a PubMed search, including all articles in the English language published until November 2021. We aimed to investigate the possible connection between SARS-CoV-2 and pityriasis rosea (PR). Pityriasis could be considered an immunological disease due to the involvement of cytokines and chemokines. Our analysis yielded 65 articles of which 53 were not considered; the others (n = 12) concerning the association between PR and COVID-19 were included in our study. We suggest two mechanisms underlying the involvement of the skin in viral infections: (i) viruses directly affecting the skin and/or inducing host immune response thus causing cutaneous manifestations; and (ii) viruses as a possible inducer of the reactivation of another virus. The first mechanism is probably related to a release of pro-inflammatory cytokine and infection-related biomarkers; in the second, several pathways could be involved in the reactivation of other latent viruses (human herpesviruses 6 and 7), such as a cytokine-cytokine receptor interaction, the Janus kinase-signal transducer and activator of transcription signaling pathway, and the IL-17 signaling pathway. We thus believe that a cytokine storm could be directly or indirectly responsible for a cutaneous manifestation. More investigations are needed to find specific pathways involved and thus confirm our speculations.

Effectiveness of acyclovir in the treatment of pityriasis rosea. A systematic review and meta-analysis

BACKGROUND

There is a lack of evidence to support acyclovir administration in pityriasis rosea.

OBJECTIVE

To determine the efficacy of acyclovir in patients with typical pityriasis rosea.

METHODS

A systematic review and meta-analysis of experimental studies was performed in MEDLINE, SCOPUS, EMBASE and others, from January 1990 to October 2016 on acyclovir for pityriasis rosea. Random effect model was used to find the pooled Risk Ratio. Outcomes, evaluated between weeks 1 to 8, were regression of lesions, cessation of lesions, decrease of symptoms and duration of disease. Comparisons were acyclovir vs. placebo; acyclovir vs. symptomatic treatment; acyclovir vs. antibiotic; acyclovir vs. observation and combined therapy (acyclovir plus symptomatic treatment) vs. symptomatic treatment alone.

RESULTS

Seven papers were analyzed with 324 participants, of which 159 received acyclovir and 165 were controls. Acyclovir was superior to placebo for complete regression of lesions at week 1 (Risk Ratio 5.72, CI95% 2.36-13.88). However, combined therapy was not superior to symptomatic treatment at week 4 (Risk Ratio 1.46, CI95% 0.93-2.29). Individual studies showed the superiority of acyclovir for the control of symptoms and pruritus.

STUDY LIMITATIONS

We faced differences designs of trials and inconsistency between reports.

CONCLUSION

Symptomatic treatment is a reasonable option for pityriasis rosea, and the addition of acyclovir is justified for the control of symptoms and pruritus.

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.

Red Cell Distribution Width and Mean Platelet Volume in Patients With Pityriasis Rosea

Background

Pityriasis rosea (PR) is an inflammatory skin disorder of unknown etiology. However, it is suggested to be related with the reactivation of human herpes virus 7 (HHV-7) and/or HHV-6. It is sometimes diffucult to distinguish PR from PR-like drug eruptions and other inflammatory disorders, so we need new parameters which are cheap and easy in determining PR. Red blood cell distribution width (RDW) and mean platelet volume (MPV) have been studied as inflammatory markers in recent studies. However, the RDW and MPV in PR patients have not been investigated. This is the first study investigating RDW and MPV parameters in PR.

Methods

This was a retrospective study of 127 patients and 127 healthy controls. MPV, RDW and the other laboratory tests were recorded.

Results

RDW levels of patients with PR were significantly lower than those of the controls (13.66 ± 2.68 and 14.00 ± 1.39, P < 0.01). The other inflammatory markers such as MPV (9.97 ± 0.99 and 10.0 ± 1.06, P = 0.7) and platelet (2.66.29 ± 62.85 and 277.41 ± 63.50, P = 0.3) were studied and statistically significant differences were not obtained. There were no significant differences found between the patient group and healthy controls in terms of hemoglobin, hematocrite, C-reactive protein (CRP), sedimentation, mean corpuscular volume (MCV), aspartate aminotransferase (AST), red blood cell (RBC), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine parameters (P > 0.05).

Conclusion

RDW can be used as a marker in diagnosing PR.

Psoriatic arthritis and psoriasis: differential diagnosis

Psoriasis frequency ranges from 1 to 3 % in white population, and arthritis occurs in 10-40 % of psoriasis patients, representing a relevant health issue. Psoriatic arthritis (PsA) is an inflammatory arthropathy, associated with psoriasis, in which ocular-, intestinal-, metabolic-, and cardiovascular-related manifestations can variably coexist. In order to favor early PsA and psoriasis diagnosis, it is crucial to rule out other conditions that can resemble the disease and delay appropriate therapeutic approach. Therefore, the aim of this review is to focus on PsA and psoriasis differential diagnosis.