Unilateral ulcerations on the forehead and scalp

We describe a patient with unilateral ulcerations on the forehead and scalp, occurring 3 months after herpes zoster infection. Further investigations were unremarkable. Histology showed epidermal and upper dermal ulceration associated with a mild nonspecific dermal inflammatory infiltrate composed of lymphoid cells and histiocytes.

Acquired palmoplantar keratoderma associated with primary biliary cholangitis: Complete and persistent resolution after ursodeoxycholic acid treatment

A 57-year-old woman presenting an acquired and persisting palmoplantar keratoderma associated with primary biliary cholangitis is reported. Treatment with oral ursodeoxycholic acid was prescribed, and a complete and persistent resolution of skin lesions was noted. This observation seems to support that acquired palmoplantar keratoderma is an uncommon cutaneous manifestation of primary biliary cholangitis.

Human CLA+ Memory T Cell and Cytokines in Psoriasis

Psoriasis is a common inflammatory skin condition resulting from the interplay between epidermal keratinocytes and immunological cellular components. This sustained inflammation is essentially driven by pro-inflammatory cytokines with the IL-23/IL-17 axis playing a critical central role, as proved by the clinical efficacy of their blockade in patients. Among all the CD45R0⁺ memory T cell subsets, those with special tropism for cutaneous tissues are identified by the expression of the Cutaneous Lymphocyte-associated Antigen (CLA) carbohydrate on their surface, that is induced during T cell maturation particularly in the skin-draining lymph nodes. Because of their ability to recirculate between the skin and blood, circulating CLA⁺ memory T cells reflect the immune abnormalities found in different human cutaneous conditions, such as psoriasis. Based on this premise, studying the effect of different environmental microbial triggers and psoriatic lesional cytokines on CLA⁺ memory T cells, in the presence of autologous epidermal cells from patients, revealed important IL-17 cytokines responses that are likely to enhance the pro-inflammatory loop underlying the development of psoriatic lesions. The goal of this mini-review is to present latest data regarding cytokines implicated in plaque and guttate psoriasis immunopathogenesis from the prism of CLA⁺ memory T cells, that are specifically related to the cutaneous immune system.

Bikini textile contact dermatitis: A Sherlockian approach revealing 2.4-dichlorophenol as a potential textile contact allergen

BACKGROUND

Different textile constituents may act as allergens and/or irritants and provoke textile contact dermatitis (TCD).

OBJECTIVES

To report a case of TCD caused by ethylene glycol monododecyl ether and 2.4-dichlorophenol, present in a bikini.

METHODS

A woman presented with an eczematous, pruritic rash in the area of the bikini straps and back. Patch testing was performed with the European baseline, textile, sunscreen, and photo-patch series, the bikini "as is", and ethanol and acetone extracts of the bikini. Thin-layer chromatography (TLC) of the extracts and gas chromatography-mass spectrometry (GC-MS) analysis were used to elucidate the culprit agents.

RESULTS

Positive reactions were found to the bikini "as is" and to the ethanol and acetone extracts. Patch testing with TLC strips showed a strong reaction to spots-fractions 3 and 4. GC-MS was performed to identify substances in each fraction and those suspected to be skin sensitisers were patch tested. On day (D) 4 positive reactions to ethylene glycol monododecyl ether (irritant reaction) and 2.4-dichlorophenol (++) were observed.

CONCLUSION

A myriad of chemical compounds can be found in clothing. Ethylene glycol monododecyl ether and 2.4-dichlorophenol were identified as the potential culprits of this bikini TCD.

HIGHLIGHTS

We have combined chemical analyses (thin-layer chromatography and gas chromatography-mass spectrometry) to study a case of textile contact dermatitis. As such, the presence of a myriad of chemical compounds was found in a bikini, suggesting that clothing in general may become impregnated or contaminated by a wide range of external substances that may be harmful to the skin. Textile contact dermatitis could in this case be attributed to ethylene glycol monododecyl ether (CAS No. 4536-30-5) and 2.4-dichlorophenol (CAS No. 120-83-2), the latter not yet previously described as a textile contact allergen.

Diagnostic Value of Genotypic Analysis in Primary Cutaneous Lymphomas using Standardized BIOMED-2 Polymerase Chain Reaction Protocols: Experience in Daily Clinical Practice

BIOMED-2 Concerted Action BMH4-CT98-3936 (BIOMED-2) PCR protocols are an important diagnostic tool in the evaluation of cutaneous lymphomas. The aim of this study was to assess the diagnostic value of the genotyping results obtained by these techniques in daily clinical practice. A total of 360 paraffin-embedded skin samples were retrospectively reviewed from 114 cutaneous T-cell lymphomas and 35 cutaneous B-cell lymphomas. A total of 249 biopsies from 180 patients with benign lymphoid infiltrates served as controls. T-cell receptor and immunoglobulin gene rearrangements were assessed using the BIOMED-2 method. A combined T-cell receptor gamma and beta assay approach reliably distinguished cutaneous T-cell lymphomas from benign skin T-cell infiltrates (sensitivity 89.4%; specificity 81.5%). Analysis of complete immunoglobulin heavy chain rearrangements also differentiated cutaneous B-cell lymphomas from benign B-cell infiltrates (sensitivity 85.7%; specificity 82.4%). In conclusion, the full BIOMED-2 protocol is a useful aid combined with clinical, histological and immunophenotypical findings for assessment of lymphoid clonality in skin lymphoid proliferations.

The Translational Relevance of Human Circulating Memory Cutaneous Lymphocyte-Associated Antigen Positive T Cells in Inflammatory Skin Disorders

Circulating memory T cells are heterogeneous in their tissue tropism. The skin-seeking T cell subset expresses the cutaneous lymphocyte-associated antigen (CLA) on their surface. CLA⁺ memory T cells not only migrate from blood to skin but also recirculate between blood and skin. Studying CLA⁺ memory T cells in cutaneous diseases has allowed a better understanding of immune-inflammatory mechanisms that take place. The analysis of the phenotypical features of these cells, their antigen specificity, cytokine production profile, and changes in relationship to clinical status and therapies among other characteristics have led to the concept that they constitute peripheral cellular biomarkers in T cell-mediated cutaneous conditions. CLA⁺ memory T cells are of relevance in the pathogenesis of several cutaneous diseases, such as psoriasis (PSO), atopic dermatitis, vitiligo, and drug-induced allergic reactions, to name a few. The interaction of circulating CLA⁺ T cells with skin-resident cells has been investigated in different ex vivo coculture models made out of clinical samples. Interestingly, microbes that are present in the skin or related with human skin diseases are preferentially recognized by CLA⁺ T cells. Thus, the interaction of Streptococcus pyogenes with CLA⁺ T cells in PSO is providing novel concepts that help to understand disease immunopathogenesis. The goal of this review is to present latest results in the field of CLA⁺ T cells in T cell-mediated inflammatory skin diseases and their translational relevance for human immunodermatology.

Diagnostic usefulness of immunohistochemical evaluation of CD1a antigen and polyclonal anti-leishmania antibodies in cutaneous leishmaniasis

BACKGROUND

Different immunohistochemical markers to detect amastigotes in cutaneous leishmaniasis have been proposed with variable diagnostic usefulness.

OBJECTIVES

To evaluate the diagnostic usefulness of immunohistochemical amastigotes identification by specific polyclonal anti-Leishmania antibodies and CD1a expression (clone EP3622) in a series of PCR confirmed cutaneous leishmaniasis.

MATERIALS AND METHODS

Thirty-three skin samples corresponding to PCR confirmed cutaneous leishmaniasis were included in the study. All samples were stained with Hematoxylin-eosin and Giemsa. Moreover, immunohistochemical studies with anti-CD1a and anti-Leishmania antibodies were performed. The patients clinical features and the observed histopathological features were also recorded.

RESULTS

From the selected 33 biopsies, Leishmania spp. amastigotes were detected in 48.4% of cases with conventional Hematoxylin-eosin stain and in 57.5% of cases by Giemsa staining. In 31/33 cases, anti-CD1a allowed us to identify parasitic structures, and in 33/33 cases amastigotes were detected with anti-Leishmania antibodies. Concordance between both techniques, anti-CD1a and anti-Leishmania, was 94% [CI 95%: (79,8%-99,3%)] ; p value <0.05. The sensitivity of anti-CD1a in comparison with the PCR was 94%, with a positive predictive value of 100%. Two cases of low parasitic index were negative for CD1a immunostaining. In cases with high parasitic index, anti-CD1a stained amastigotes in superficial and deep dermis. Only a few cases were originally diagnosed with the available histological techniques, needing PCR for Leishmania spp.

CONCLUSIONS

Anti-CD1a antibody seems to be a useful technique to identify amastigotes when PCR and anti-Leishmania antibodies are not available. The sensitivity to detect amastigotes is increased when the CD1a immunostaining is added to the classical Haematoxylin - eosin and Giemsa staining.

Wound infection by Pantoea agglomerans after penetrating plant injury

Pantoea agglomerans is a ubiquitous gram-negative bacterium that has been linked to skin and joint infections secondary to plant injuries. Herein we report a 58-year-old woman who presented with 2 erythematous nodules with purulent discharge on the anterior aspect of the right leg that developed after a penetrating plant injury. The patient was initially treated with amoxicillin-clavulanic acid, cloxacillin and clindamycin without improvement. P. agglomerans was isolated from both exudate and skin biopsy cultures. Healing of the lesions was achieved after the spontaneous release of a retained plant fragment and treatment with cotrimoxazole. Identification of P. agglomerans in persistent exudative lesions should alert the clinician regarding a possible previous plant injury and retained vegetal fragments. Conventional antibiotic treatment and the extraction of retained foreign bodies usually lead to complete resolution.

Burden of Psoriasis in Catalonia: Epidemiology, Associated Comorbidities, Health Care Utilization, and Sick Leave

BACKGROUND AND OBJECTIVES

Epidemiologic and disease burden data are essential for disease control and optimal health care resource planning. The aims of this study were to estimate the epidemiologic burden of psoriasis and evaluate associated comorbidities, health care utilization, and sick leave.

MATERIAL AND METHODS

We collected data from the 2016 Catalan Health Survey (ESCA), the Catalan Registry of Morbidity and Utilization of Health Care Services (MUSSCAT) (2016), and the database of the Catalan Medical Evaluations Institute (ICAM) (2012-2016).

RESULTS

The prevalence of psoriasis in Catalonia according to 2016 ESCA data is approximately 1.8%. The MUSSCAT registry data indicate that the incidence has remained stable in recent years. The most common comorbidities associated with psoriasis are hypertension (35%) and diabetes (15%). Forty percent of patients with psoriasis have a moderate to high risk for death or high health resource utilization. Annual use of resources by psoriasis patients is high: they make a mean of 8.7 primary care visits, 2.8 outpatient visits, 0.5 emergency and day hospital visits, 0.2 mental health visits, and use 6.1 medications. Sick leave due to psoriasis or psoriatic arthritis accounted for 0.04% of all cases.

CONCLUSIONS

The prevalence of psoriasis in Catalonia is high at 1.8%. The disease burden is also high, both in terms of comorbidities and health care utilization.

Medicolegal Aspects of Teledermatology

Teledermatology has facilitated specialist care during the crisis caused by the coronavirus disease 2019 pandemic, eliminating unnecessary office visits and the possible exposure of patients or dermatologists. However, teledermatology brings forward certain ethical and medicolegal questions. A medical consultation in which the patient is not physically present is still a medical act, to which all the usual ethical and medicolegal considerations and consequences apply. The patient's right to autonomy and privacy, confidentiality, and data protection must be guaranteed. The patient must agree to remote consultation by giving informed consent, for which a safeguard clause should be included. Well-defined practice guidelines and uniform legislation are required to preserve the highest level of safety for transferred data. Adequate training is also needed to prevent circumstances involving what might be termed «telemalpractice».

Diffuse dermal mucinosis secondary to colony-stimulating factor 1 receptor monoclonal antibody treatment: A novel and peculiar drug-induced diffuse cutaneous mucinosis

Colony-stimulating factor 1 receptor (CSF1R) inhibitors represent a new class of immune-modulatory drugs, mostly investigated in clinical trials in different malignant neoplasms. Four patients, diagnosed with recurrent or advanced malignant neoplasm and treated with a combination of anti-programmed death ligand 1 and anti-CSF1R monoclonal antibodies, developed an asymptomatic cutaneous eruption characterized by an ill-defined pseudoedematous to waxy diffuse infiltration with a reticular cobblestone-like pattern. Histopathological examination revealed diffuse mucin deposition involving the superficial and mid-dermis with fragmented and scattered elastic fibers. The exact pathogenic mechanisms implicated in the development of mucin deposits in patients treated with CSF1R inhibitors remain to be elucidated. A reduced degradation and clearance of components of the extracellular matrix by macrophages secondary to CSF1 pathway inhibition may be hypothesized. Shredding and fragmentation of elastic fibers may be a result of the increased accumulation of mucopolysaccharides. This observation illustrates the new spectrum of skin-related toxicities secondary to new targeting therapies. This may contribute to a better understanding of the underlying pathogenic mechanisms in skin diseases characterized by a persistent dermal glycosaminoglycan deposition.

Two-Step Digital Follow-up of Patients at High Risk for Melanoma: a Retrospective Analysis of 152 Patients

BACKGROUND

Digital dermoscopy (DD) has been found to improve the accuracy of melanoma diagnosis in high-risk patients. A 2-step approach combining DD and total-body photography (TBP) can facilitate the detection of new lesions or early macroscopic changes in existing lesions.

OBJECTIVES

The aim of this study was to determine the number of biopsies needed to diagnose melanoma and to describe the clinical and dermoscopic characteristics of melanoma diagnosed in patients with pigmented lesions under follow-up with DD and TBP.

PATIENTS AND METHODS

Retrospective study of 152 patients with a high risk of melanoma who were followed using a 2-step digital approach at Hospital del Mar in Barcelona, Spain, between 2002 and 2016. We analyzed the characteristics of pigmented lesions excised after macroscopic changes were detected by periodic DD and TBD.

RESULTS

Biopsy results of 99 lesions (84 dysplastic nevi, 13 melanomas, and 2 compound melanocytic nevi) showed a ratio of benign melanocytic lesions to melanomas of 1:6.6. The mean Breslow thickness was 0.19 mm. Macroscopic changes were significantly more common in melanomas than in melanocytic nevi (P = 0.018). Dermoscopic findings associated with melanoma were asymmetric growth and focal structural changes (P < 0.001). The specific features associated with a diagnosis of melanoma were asymmetry (P < 0.001), a reverse pigment network (P = 0.011), atypical globules (P = 0.011), and polymorphous vessels (P = 0.045).

CONCLUSIONS

TBP follow-up is a useful tool for the early diagnosis of melanoma. In our series, 50% of melanomas diagnosed during digital follow-up were detected by observation of a new lesion via TBP mapping or macroscopic changes in an existing lesion. Dermoscopic follow-up is essential in patients at high risk for melanoma as both melanocytic nevi and melanoma show a range of specific dermoscopic features, and a diagnosis of melanoma can only be based on a record of changes in the appearance of lesions during follow-up.

Medicolegal aspects of teledermatology

Teledermatology has facilitated specialist care during the crisis caused by the coronavirus disease 2019 pandemic, eliminating unnecessary office visits and the possible exposure of patients or dermatologists. However, teledermatology brings forward certain ethical and medicolegal questions. A medical consultation in which the patient is not physically present is still a medical act, to which all the usual ethical and medicolegal considerations and consequences apply. The patient's right to autonomy and privacy, confidentiality, and data protection must be guaranteed. The patient must agree to remote consultation by giving informed consent, for which a safeguard clause should be included. Well-defined practice guidelines and uniform legislation are required to preserve the highest level of safety for transferred data. Adequate training is also needed to prevent circumstances involving what might be termed "telemalpractice."

Severe Autoinflammatory Manifestations and Antibody Deficiency Due to Novel Hypermorphic PLCG2 Mutations

Autoinflammatory diseases (AIDs) were first described as clinical disorders characterized by recurrent episodes of seemingly unprovoked sterile inflammation. In the past few years, the identification of novel AIDs expanded their phenotypes toward more complex clinical pictures associating vasculopathy, autoimmunity, or immunodeficiency. Herein, we describe two unrelated patients suffering since the neonatal period from a complex disease mainly characterized by severe sterile inflammation, recurrent bacterial infections, and marked humoral immunodeficiency. Whole-exome sequencing detected a novel, de novo heterozygous PLCG2 variant in each patient (p.Ala708Pro and p.Leu845_Leu848del). A clear enhanced PLCγ2 activity for both variants was demonstrated by both ex vivo calcium responses of the patient's B cells to IgM stimulation and in vitro assessment of PLC activity. These data supported the autoinflammation and PLCγ2-associated antibody deficiency and immune dysregulation (APLAID) diagnosis in both patients. Immunological evaluation revealed a severe decrease of immunoglobulins and B cells, especially class-switched memory B cells, with normal T and NK cell counts. Analysis of bone marrow of one patient revealed a reduced immature B cell fraction compared with controls. Additional investigations showed that both PLCG2 variants activate the NLRP3-inflammasome through the alternative pathway instead of the canonical pathway. Collectively, the evidences here shown expand APLAID diversity toward more severe phenotypes than previously reported including dominantly inherited agammaglobulinemia, add novel data about its genetic basis, and implicate the alternative NLRP3-inflammasome activation pathway in the basis of sterile inflammation.