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

L-lysine: its antagonism with L-arginine in controlling viral infection. Narrative Literature Review

Knowledge about viral characteristics, mechanisms of entry into the host cell and multiplication/dissemination can help in the control and treatment of viral pathologies. Several nutritional factors linked to the host may favor viral multiplication and their control, may lead to new prophylactic alternatives and/or antiviral therapies. The objective of this review is to discuss the relationship between the amino acid L-lysine and the control of viral infections, aiming at a possible therapeutic property. This research used databases such as PubMed, Web of Science, Scielo, Medline and Google Scholar, as well as searching for references cited by journals. The time frame covered the period between 1964 and January 2022. The observed studies have shown that the usual antiviral therapies are not able to interfere with the viruses in their latent state, however, they can interfere with the adhesion and fusion of viral particles or the production of proteins, which play an important role in viral epidemiology and control, particularly in the initial moment and in the reactivation. Lysine is an amino acid that can interfere mainly in the formation of capsid proteins and DNA by a competitive antagonism with amino acid arginine, which is an essential amino acid for some viruses and also by promoting the increase of arginase, increasing the catabolism of arginine. Although there is evidence of the importance of L-lysine in viral control, more studies are needed, with a view to new antiviral therapies.

Pityriasis Rosea: An Updated Review

BACKGROUND

Pityriasis rosea is a common acute, self-limited papulosquamous dermatosis that primarily affects children and young adults. The condition and its clinical variants may pose a diagnostic challenge, especially in the absence of the herald patch.

OBJECTIVE

This article aimed to familiarize pediatricians with clinical manifestations, evaluation, diagnosis, and management of pityriasis rosea.

METHODS

A search was conducted in March 2020 in Pubmed Clinical Queries using the key term " pityriasis rosea". The search strategy included all clinical trials (including open trials, non-randomized controlled trials, and randomized controlled trials), observational studies, and reviews (including narrative reviews and meta-analyses) published within the past 10 years. Only papers published in the English literature were included in this review. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Pityriasis rosea occurs mainly in individuals between 10 and 35 years of age with a peak during adolescence. Human herpesvirus (HHV)-7 and HHV-6 have been implicated as the causative agents in some patients with pityriasis rosea. A mild prodrome consisting of headaches, fever, malaise, fatigue, anorexia, sore throat, enlarged lymph nodes and arthralgia is present in about 5% of patients. The most common presenting sign, found in approximately 80% of patients, is a "herald" or "mother" patch which is larger and more noticeable than the lesions of the later eruption. A generalized, bilateral, symmetrical eruption develops in approximately 4 to 14 days and continues to erupt in crops over the next 12 to 21 days. Typical lesions are 0.5 to 1 cm, oval or elliptical, dull pink or salmon-colored macules with a delicate collarette of scales at the periphery. The long axes tend to be oriented along the skin lines of cleavage (Langer lines). Lesions on the back may have a characteristic "Christmas tree", whereas lesions on the upper chest may have a V-shaped pattern. There are many conditions that may mimic pityriasis rosea. Pityriasis rosea in the absence of the herald patch and its variants may pose a diagnostic challenge. The typical course is 6 to 8 weeks. In the vast majority of cases, reassurance and symptomatic treatment should suffice. Active intervention may be considered for individuals with severe or recurrent pityriasis rosea and pregnant women with the disease. Treatment options include acyclovir, macrolides (in particular, erythromycin), and ultraviolet phototherapy. If active intervention is needed, there is evidence supporting the use of oral acyclovir to shorten the duration of illness.

CONCLUSION

Pityriasis rosea is a common, acute, self-limiting exanthematous skin disease that primarily affects children and young adults. The condition is characterized by a "herald patch" after which oval erythematous squamous lesions appear along Langer's lines of cleavage on the trunk and proximal extremities, giving it a "Christmas tree" appearance. The disease presenting in its classical form can easily be diagnosed. Clinical variants of the disease may pose a diagnostic challenge for the general pediatrician. Knowledge of the disease is essential to allow prompt diagnosis and to avoid unnecessary investigations.

L-lysine therapy to control the clinical evolution of pityriasis rosea: Clinical case report and literature review

Pityriasis rosea (PR) is a dermatological disease with an erythemato-papulosquamous manifestation, distributed on the trunk and extremities affecting healthy people, especially children and young people between 10 and 35 years of age. The evolution is 6 to 8 weeks and may remain for 3 to 6 months. It regresses spontaneously and can leave changes in the skin color but reversibly. Acyclovir is indicated to minimize clinical manifestations with the suspected of viral association (HHV-6 and 7). Another group of the human herpesvirus family (HHV-1 and 2), causes herpes simplex that is controlled with the antivirals, including acyclovir, as well as the amino acid L-lysine, both showing positive and similar results in reducing the number of annual manifestations and the healing time of the lesions. The aim of this study is to report a case of PR in a child, to review the literature on the etiopathogenesis of the disease and on the effects of L-lysine as well as another amino acid in the treatment. An 11-year-old girl, phototype II, presented lesions diagnosed as PR. The cycle would be 6 to 8 weeks on average. A solution of L-lysine was prescribed for 30 days, on an empty stomach. After the fourth day of therapy, the cycle of new eruptions was interrupted, initial lesions regressed, accelerating the repair of larger lesions resulting in an improvement of the clinical condition. We concluded that the administration of L-lysine, in therapeutic doses, can be a safe alternative for the PR control.