Langerhans cell histiocytosis (LCH) is a clonal proliferation of pathologic cells with the characteristics of Langerhans cells. It has a broad spectrum of manifestations, ranging from a benign single-system presentation to a severe multi-system disease.
We report a case of a generally well two-day old boy who was referred to our service for multiple papules and vesicles noted at birth that rapidly progressed into erythematous papules and macules, some topped with yellowish and hemorrhagic crusts. Initial assessment by Pediatrics was possible herpes simplex virus or varicella infection, which was supported by a positive Tzanck smear. However, pertinent laboratory examinations were negative. Skin biopsy showed proliferation of large epithelioid histiocytes with large vacuolar reniform nuclei in the dermis. Immunohistochemical staining with CD1A was positive. The results were consistent with LCH. The early onset of skin lesions, lack of systemic involvement, and rapid improvement, point to a diagnosis of a single system LCH or the congenital self-healing variant. A positive Tzanck smear in a case of LCH has previously been reported in literature and is attributed to histiocytes viewed on examination. Upon discharge, the remaining lesions were light brown macules. Monitoring was done on an outpatient basis.
LCH is diagnosed based on the histopathologic evaluation of involved skin tissue interpreted within the clinical context. It is confirmed by appropriate positive immunohistochemical staining. Relevant diagnostic examinations are needed to rule in a diagnosis of the congenital self-healing variant. While it is typically benign, monitoring is still warranted given the possibility of relapse or progression.

Human ; Male ; Infant Newborn ; Chickenpox ; Dermis ; Histiocytes ; Histiocytosis, Langerhans-cell ; Langerhans Cells ; Pediatrics ; Recurrence ; Simplexvirus ; Skin ; Skin Diseases ; Staining And Labeling ; Vacuoles

Introduction: Erythema multiforme has been known as an infection or drug-associated mucocutaneous eruption characterized by target lesions. A clinical entity, known as Mycoplasma-induced rash and mucositis seen mostly in the pediatric population is emerging and may be associated with atypical pneumonia caused by Mycoplasma pneumoniae. This presents with features overlapping with erythema multiforme and SJS-TEN spectrum but with a different trigger, prognosis, and recurrence rate. Case summary: Target lesions in the clinical setting are usually characteristically associated with erythema multiforme, a mucocutaneous condition associated with an underlying infectious trigger. We present a case of a 10-year-old Filipino boy who was initially diagnosed with erythema multiforme major. Eventual testing for the etiology of the underlying infection, Mycoplasma pneumoniae, proved to be a useful diagnostic that gave a better grasp on the case’s mechanism, sequela, and prognosis. The patient was admitted for pneumonia and his presenting mucositis was severe. Cutaneously, he had atypical target and few target lesions on the trunk and extremities. He was diagnosed as a case of Mycoplasma-induced rash and mucositis (MIRM) and treated with antibiotics and systemic steroids for which he recovered fully in three weeks. MIRM should be separated from erythema multiforme, Stevens Johnsons syndrome and toxic epidermal necrolysis as it follows a different disease course. Conclusion: Mycoplasma-induced rash and mucositis is now considered a distinct entity despite it having overlapping features with erythema multiforme and SJS-TEN spectrum. It presents usually in the younger age group with absent to sparse atypical vesiculobullous or targetoid lesions, significant mucosal involvement, and confluent necrosis on histology. It is important to identify it as a trigger because of its more frequent and severe mucosal sequelae. Management includes symptomatic relief, antibiotic therapy with a macrolide in the presence of pneumonia and systemic steroids when mucositis is severe. Majority of patients achieve full recovery.
Erythema Multiforme ; Mycoplasma pneumoniae ; Mucositis ; Exanthema

CASE SUMMARY: A 51-year-old Filipino female without comorbidities presented with cough, rhinitis, and low-grade fever. Four days later, she developed pruritic, localized wheals on the arms, gradually involving the trunk and lower extremities. A 49-year-old Filipino female without comorbidities based in the Middle East presented with cough and fever. Four days after, she developed a generalized distribution of wheals and livedoid patches on both legs. Both patients recovered from COVID-19 with complete resolution of skin lesions. CONCLUSION: To the best of our knowledge, this is the first report of COVID-19 related dermatology cases collected in the Philippines.
Mucocutaneous Lymph Node Syndrome ; SARS-CoV-2 ; COVID-19 ; Administration, Cutaneous ; Exanthema ; Skin ; Virus Diseases ; Toes

Introduction: Atopic dermatitis (AD) is a complex disease with an interplay of genetic and environmental factors. In the United States, AD affects 10.7% of children andyc 7.2% of adults. Similarly in the Philippines, the prevalence of AD is 12.7% in the under 18 population, and 2% in the over 18 population. While AD affects all ages, the burden of the disease is greater in the pediatric population. The pathogenesis of AD is multifactorial. Variations in genes responsible for epidermal barrier function, keratinocyte terminal differentiation, and the innate and adaptive immune responses have been linked to AD. A null mutation involving the filaggrin gene is the strongest known risk factor for AD. This mutation results in a loss of filaggrin (FLG) protein by at least 50%. Filaggrin breakdown products form part of the natural moisturizing factor (NMF) of the skin, which is essential in skin hydration. A decrease in NMF and an increase in transepidermal water loss (TEWL) are observed in AD patients with FLG mutation. The defective barrier in AD patients decreases skin defenses against irritation and allergen penetration. Exposure to certain environmental chemicals like formaldehyde may worsen this barrier. This may lead to increased skin permeability to aeroallergens that leads to dermatitis in sensitized patients. Barrier defects may also play a role in epicutaneous sensitization and the subsequent development of other atopic conditions, such as bronchial asthma and allergic rhinitis. The Philippine Dermatological Society (PDS) consensus on AD aims to provide a comprehensive guideline and evidence-based recommendations in the management of this condition, with consideration of cultural factors that are often encountered in the Philippine setting. These guidelines are intended to provide practitioners with an overview of the holistic approach in the management of AD, ameliorating the negative effects of the disease and improving overall quality of life.. Methodology: A group of 21 board-certified dermatologists from the Philippine Dermatological Society (PDS) convened to discuss aspects in the clinical management of AD. Database and literature search included the full-text articles of observational studies, randomized controlled clinical trials, and observational studies using the Cochrane library, PubMed, Hardin (for Philippine based studies) as well as data from the PDS health information system. The terms used in combinations from the literature included “atopic dermatitis”, “atopic eczema”, “emollients”, “topical corticosteroids”, “topical calcineurin inhibitors”, “anti-histamines” and “phototherapy”. A total of fifty (50) full text articles were reviewed and found applicable for the scope of the study. Articles were assessed using the modified Jadad scale, with score interpretations as follows: (5- excellent, 3- good, 1– poor). Consensus guidelines for AD from within and outside of the region were also reviewed, from the 2013 Asia-Pacific guidelines, 2014 Taiwanese Dermatological Association consensus, 2016 guidelines in the management of AD in Singapore, 2014 American Academy of Dermatology guidelines, and the 2020 Japanese guidelines for AD. From the literature review, proposed consensus statements were developed, and a Delphi survey was conducted over two separate virtual meetings. Individual dermatologists provided Likert Scoring (1- strongly disagree to 5- strongly agree) based on consensus statements. A consensus was deemed reached at mean scores of > 4.00, a near consensus at > 3.5, and no consensus at <3.5. Summary: AD is a chronic relapsing condition with a significant burden of disease, most commonly affecting the pediatric population. The PDS AD Consensus Guidelines summarizes the standards of therapy and the therapeutic ladder in the management of AD based on published clinical trials and literature review. While these modalities remain the cornerstone of therapy, an individualized approach is the key to the holistic management of an AD patient. Knowledge and awareness of frequently associated conditions, whether in the realm of food allergies, contact allergies, or secondary infections, is paramount. In addition to the standard therapeutic armamentarium, the physician must also consider cultural practices and be knowledgeable of alternative therapeutic options. Referral to a specialist is recommended for recalcitrant cases of AD, or when initiation of systemic immunosuppressive agents, phototherapy, or biologic agents is contemplated.