[Androgenetic alopecia: where do we stand in 2024?] / Alopécie androgénétique : où en est-on en 2024 ?

Androgenetic alopecia, the most prevalent type of hair loss, is characterized by a receding hairline in men and diffuse thinning of hair in women. Despite being considered a benign condition, it can exert a considerable psychological toll, especially on women and young men. Despite its high prevalence, only a limited number of medications have received approval for its treatment. In this article, we review the available treatment options, assessing their efficacy and potential side effects. Additionally, we explore minimally-invasive strategies such as photobiomodulation, micro-needling and platelet-rich plasma therapy. Furthermore, we delve into discussions on hair transplantation and camouflage methods.

L'alopécie androgénétique (AAG) est la forme la plus fréquente de perte de cheveux, caractérisée par le recul de la ligne frontale des cheveux chez les hommes et l'élargissement des lignes de partage des cheveux chez les femmes avec épargne de la ligne frontale. L'AAG, considérée comme une pathologie bénigne, a toutefois un impact psychologique pouvant être très important, notamment chez les femmes et les jeunes hommes. Bien qu'il s'agisse d'une entité très répandue, peu de médicaments sont approuvés pour son traitement. Dans cet article, nous parcourons les différentes options thérapeutiques disponibles, leurs efficacités et effets secondaires ainsi que les traitements minimalement invasifs tels que la photobiomodulation, aiguilletage de la peau ou encore le plasma riche en plaquettes. Nous discutons également de la greffe capillaire et des méthodes de camouflages.

Perforating Fibrous Histiocytoma Mimicking Keratoacanthoma: A Case Report.

A 31-year-old male presented with a firm, well-demarcated, erythematous, crateriform, and ulcerated nodule in the left lumbar region, which persisted for 3 months. Clinically, a keratoacanthoma was suspected. The histological analysis was consistent with perforating fibrous histiocytoma, a rare histopathologic variant of fibrous histiocytoma. To our knowledge, this is the third case reported in the literature.

Pseudomalignancies in Children: Histological Clues, and Pitfalls to Be Avoided.

The term "pseudomalignancy" covers a large, heterogenous group of diseases characterized by a benign cellular proliferation, hyperplasia, or infiltrate that resembles a true malignancy clinically or histologically. Here, we (i) provide a non-exhaustive review of several inflammatory skin diseases and benign skin proliferations that can mimic a malignant neoplasm in children, (ii) give pathologists some helpful clues to guide their diagnosis, and (iii) highlight pitfalls to be avoided. The observation of clinical-pathological correlations is often important in this situation and can sometimes be the only means (along with careful monitoring of the disease's clinical course) of reaching a firm diagnosis.

Pityriasis Lichenoides: A Large Histopathological Case Series With a Focus on Adnexotropism.

INTRODUCTION: Pityriasis lichenoides (PL) is an infrequent skin disorder. The clinical manifestations are usually specific enough for a reliable diagnosis, although the histopathological assessment of a biopsy is sometimes needed to differentiate between PL and a range of other diseases. The objectives of this study were to review cases of PL managed in our hospital, confirm the classical histopathological features of PL, and identify signs that may be of value in the diagnosis of PL. MATERIALS AND METHODS: All cases of PL assessed in our pathology department between January 2007 and December 2017 were retrieved, and all slides were reviewed. Cases were selected only if a diagnosis of PL was initially suggested by a dermatologist and then confirmed by the histopathological assessment. RESULTS: Seventy-one cases met the study criteria. The following features were almost always present: vacuolar changes or necrotic keratinocytes (100%), both superficial and deep lymphocytic infiltrates (99%), and the infiltration of lymphocytes into the adnexal epithelium (97%). The inflammatory cells were always small- to medium-sized lymphocytes. There were no eosinophilic infiltrates. Superficial perivascular and/or intraepidermal red blood cells were observed in 83% of cases. DISCUSSION: We highlighted the presence of a deep dermal lymphocytic infiltrate, with a "T-shaped" periadnexal arrangement along the full length of the follicular and sudoral epithelia. This might be a feature that enables the differentiation of PL from other diseases. Our findings also prompted a number of physiopathological hypotheses for PL. CONCLUSIONS: Our present results confirmed the classical histological aspects of PL and provided some useful new diagnostic features.

Cutaneous Mucormycosis Resulting from Hematogenous Dissemination of Rhizomucor pusillus in an Immunocompromised Patient.

Rhizomucor pusillus is an opportunistic fungus that causes infections (mucormycosis) in patients with a predisposing disease, such as diabetes mellitus and immunodeficiency. Classic manifestations are sinus, pulmonary, and skin infections. Skin lesions consist of tender, erythematous, indurated, and necrotic plaques. The diagnosis is made by identification of the organisms by histopathological analysis of the lesion, showing nonseptate fungal hyphae in the dermis and invasion of the vessel walls, or by means of cultures. Amphotericin B and surgery are the treatments of choice.

Morphological Analysis of Dermatoporosis by in vivo Reflectance Confocal Microscopy and Ultrasonography.

BACKGROUND: Dermatoporosis is defined as a chronic cutaneous fragility and insufficiency syndrome. It results from chronological aging, long-term and unprotected sun exposure, genetic factors, or the chronic use of topical and systemic corticosteroids. There is currently a lack of noninvasive tools for the evaluation and quantification of dermatoporosis. OBJECTIVES: The aim of this study was to define the dermal-epidermal modifications which characterize dermatoporosis using noninvasive methods such as in vivo reflectance confocal microscopy (RCM) and ultrasound (US). SUBJECTS AND METHODS: Seventeen patients with stage I dermatoporosis and 14 healthy volunteers were included in the study. The posterior surface of the right forearm was analyzed in all subjects, and stellate pseudoscars and senile purpura in patients with dermatoporosis were analyzed when possible. We used a commercially available reflectance confocal microscope and measured different histometric parameters (thickness of the epidermis and its different layers, cellular architecture, aspect of the dermal-epidermal junction and the dermis). We also used a commercially available US skin system to define the dermal-epidermal thickness (DET) in all subjects. RESULTS: The DET measured with the US skin system was significantly different between the two groups: mean value 1.19 mm (volunteers group) versus 0.81 mm (patient group). The significant differences measured with RCM were (1) epidermal thickness, (2) number of dermal papillae, and (3) thickness of solar elastosis. Stellate pseudoscars are also characterized by a modified dermis, with a linear organization of the collagen bundles. CONCLUSION: US and in vivo RCM are useful tools for the diagnosis of dermatoporosis. Dermal-epidermal atrophy, reduction of dermal papillae/area, and the thickness of dermal elastosis seem to be the major histometric parameters which characterize dermatoporosis.

Successful Treatment of Scalp Myxedema with Injected Hyaluronidase: A Case Report.

Localized myxedema is an uncommon complication of Graves' disease. It is characterized by the accumulation of glycosaminoglycans, particularly hyaluronate. Here we describe the case of a 51-year-old female patient suffering from Graves' disease, who has presented for years a thickening of the scalp, consistent with myxedema, and successfully treated with repeated injections of hyaluronidase.

[Evaluation and management of hyperhidrosis]. / Evaluation et prise en charge de l'hyperhidrose.

Hyperhidrosis is excessive sweating beyond what is expected for thermoregulatory needs. Nearly 3 % of the population has hyperhidrosis. It may be primary or secondary to medications or general medical conditions, including diabetes mellitus, hyperthyroidism, Parkinson disease, etc. History taking and clinical examination are essential to differentiate primary from secondary origins. Blood tests and a consultation with a specialist (endocrinologist, neurologist) is sometimes necessary to establish the diagnosis. The management of secondary hyperhidrosis involves the treatment of the underlying cause. For primary hyperhidrosis, it depends on its severity and the sites affected. This article will review the treatments for primary hyperhidrosis.

L'hyperhidrose est définie par une production de sueur qui dépasse les quantités nécessaires à la thermorégulation. Elle toucherait jusqu'à 3 % de la population. Elle peut être primaire (idiopathique), ou secondaire à un médicament ou diverses affections médicales, telles que le diabète, l'hyperthyroïdie, la maladie de Parkinson, etc. Une anamnèse et un examen clinique complets permettent de détecter les origines secondaires. Un bilan biologique et éventuellement une consultation par un spécialiste (endocrinologue, neurologue) seront parfois nécessaires pour le diagnostic. La prise en charge de l'hyperhidrose secondaire passe par le traitement de la cause sous-jacente, tandis que pour l'hyperhidrose primaire, elle dépend de sa sévérité et des sites touchés. Cet article passera en revue les différents traitements reconnus de l'hyperhidrose primaire.

Injected Hyaluronidase Reduces the Volume of Exogenous Hyaluronate Fillers in Mice and Results in Clinical Improvement in a Patient with Pretibial Myxedema.

BACKGROUND: Hyaluronidases are essential for the breakdown of hyaluronate (HA) in tissues and may be used to prevent the adverse effects of HA fillers. OBJECTIVES: We explored the effect of hyaluronidase on exogenous and endogenous HA in vitro and in vivo. MATERIALS AND METHODS: HA fillers were incubated with different concentrations of hyaluronidase and visualized by electrophoresis. HA fillers were injected in the skin of hairless mice, and 4 h later hyaluronidase was injected in the papules of exogenous HA. Hyaluronidase was injected in the nodule of pretibial myxedema of a male patient with Graves' disease. Skin sections of mice and of the patient were performed, and a skin ultrasound system was used to monitor the evolution of skin lesions. RESULTS: Hyaluronidase showed a degrading effect on HA with increasing concentrations. Hyaluronidase injection significantly decreased the content of exogenous HA within 3 days. Intralesional injection of hyaluronidase resulted in dissolution of the nodule of pretibial myxedema with no recurrence during 3 months. CONCLUSION: These results show that the injection of hyaluronidase is capable of degrading exogenous HA in mouse skin and endogenous HA in human skin in vivo and may be a therapeutic option for skin diseases characterized by abnormal accumulation of HA.

[Skin symptoms of psoriasis associated with spondylarthropathies]. / Manifestations cutanées du psoriasis associées aux spondylarthropathies.

The term spondylarthropathy summarizes a heterogenous group of diseases with spinal involvement as the common denominator. In this paper, we will primarily focus on cutaneous manifestations of psoriasis, as this dermatosis is associated with psoriatic artrhritis, one of the major diseases classified as spondylarthropathy. We will describe the clinical manifestations of psoriasis as well as the underlying pathophysiology, the latter allowing to understand the differences in efficacy of numerous Disease Modifying Anti-Rheumatic Drugs (DMARDs) on joint versus skin symptoms. Additionally, we address the exacerbation of pre-existing psoriasis under DMARD therapy.