Luis J. Borda

Seborrheic Dermatitis and Dandruff: A Comprehensive Review

Seborrheic Dermatitis (SD) and dandruff are of a continuous spectrum of the same disease that affects the seborrheic areas of the body. Dandruff is restricted to the scalp, and involves itchy, flaking skin without visible inflammation. SD can affect the scalp as well as other seborrheic areas, and involves itchy and flaking or scaling skin, inflammation and pruritus. Various intrinsic and environmental factors, such as sebaceous secretions, skin surface fungal colonization, individual susceptibility, and interactions between these factors, all contribute to the pathogenesis of SD and dandruff. In this review, we summarize the current knowledge on SD and dandruff, including epidemiology, burden of disease, clinical presentations and diagnosis, treatment, genetic studies in humans and animal models, and predisposing factors. Genetic and biochemical studies and investigations in animal models provide further insight on the pathophysiology and strategies for better treatment.

Wound Dressings: A Comprehensive Review

Purpose of ReviewThis comprehensive review covers the advantage and limitations of some dressing materials and the current knowledge on wound dressings and emerging technologies to achieve proper wound healing.Recent FindingsTraditional and modern dressings are helpful in the wound healing process; however, they cannot substitute lost tissue. Human skin equivalents have been developed conceptually to fill this void as they do not only facilitate wound healing but also may replace lost tissue. Several studies have shown that the addition of mesenchymal stem cells, such as in human placenta, has promising results in wound healing.SummaryA wound is defined as a disruption in the continuity of the skin or mucosa due to physical or thermal damage, or an underlying medical condition. Wound healing is a complex, dynamic, and multistep process which occurs after skin damage leading to tissue repair. Although the skin normally undergoes repair after a disruption, the healing process can be affected in different conditions such as diabetes mellitus, infections, venous/arterial insufficiency, among others. To enhance healing, a wide range of wound dressings are available; however, a thorough wound assessment (e.g., wound type, size, depth, or color) is required to choose the appropriate dressing. The emergence of new dressings has brought a new perspective of wound healing, but there is no superior product yet to treat acute and/or chronic wounds. Therefore, wound dressing research studies need to be carried out in order to help improve wound healing.

Loss of MPZL3 function causes seborrhoeic dermatitis‐like phenotype in mice

Seborrhoeic Dermatitis (SD) is a common inflammatory skin disorder. It is chronic and relapsing, affecting 1%–3% of the general adult population.1 SD presents as pink to red greasylooking skin with yellowish scales in seborrhoeic areas such as the scalp, face (nasolabial folds, upper lip, eyelids and eyebrows), retroauricular area and the upper chest. It can be pruritic and socially embarrassing. Current treatment includes antifungals, antiinflammatory and immune modulators, but treatment in some patients may cause adverse effects such as skin atrophy and telangiectasia if used long term. Sebaceous secretion, yeast Malassezia infection and individual susceptibilities such as host immunity and epidermal barrier integrity have all been identified as predisposing factors and may work together to worsen disease. In 2006, Birnbaum et al.2 demonstrated that a frameshift mutation in ZNF750, a zinc finger transcription factor and master regulator of epidermal differentiation, causes early onset (<10 years of age) autosomal dominant seborrhoealike psoriasiform dermatitis with 100% penetrance (OMIM #610227). Yet, how ZNF750 dysfunction causes the SD phenotype remains unknown. We have previously generated knockout mice to determine MPZL3 (myelin protein zerolike 3) function in the skin. Mpzl3 encodes an immunoglobulin protein and is expressed in the suprabasal layers of mouse epidermis, the sebaceous gland and anagen hair follicles.3,4 Not surprisingly, Mpzl3 knockout mice showed various skin abnormalities, including epidermal and sebaceous hyperplasia and hair loss.3–5 Interestingly, these mice also developed early onset skin inflammation with dandrufflike flakes.4 Importantly, ZNF750 was recently shown to directly bind to MPZL3 promoter and activate its transcription in cultured human keratinocytes.6 Therefore, Mpzl3 knockout mice can serve as a useful model to understand SD pathogenesis caused by ZNF750 dysfunction.

Patients’ prediction of their wound healing time: Patients’ prediction of wound healing time

Understanding and managing patients’ expectations can help improve their adherence to treatment for chronic wounds; however, little is known concerning about their expectations regarding healing time. Recruited subjects were asked to predict how long their wounds would take to heal and their charts were reviewed to retrieve real time of healing. We recruited 100 subjects from which 77% have healed. Fifty‐three subjects (68.8%) had a longer healing time than they predicted (underestimated), and 17 (22.1%) had a shorter healing time than they predicted (overestimated). Subjects with shorter wound duration history tended to predict shorter healing time than subjects with longer wound duration (p < 0.01). However, wound duration did not affect prediction accuracy (p = 0.65). Subjects with chronic wounds seem more often to underestimate their time of healing. Wound duration significantly influenced patients’ prediction time, although it did not make their prediction more accurate. Patient education about expectations may be important as patients often expect their wounds to heal faster than they actually do.

Treatment of seborrheic dermatitis: a comprehensive review

Abstract Seborrheic dermatitis (SD) is a chronic, recurring inflammatory skin disorder that manifests as erythematous macules or plaques with varying levels of scaling associated with pruritus. The condition typically occurs as an inflammatory response to Malassezia species and tends to occur on seborrheic areas, such as the scalp, face, chest, back, axilla, and groin areas. SD treatment focuses on clearing signs of the disease; ameliorating associated symptoms, such as pruritus; and maintaining remission with long-term therapy. Since the primary underlying pathogenic mechanisms comprise Malassezia proliferation and inflammation, the most commonly used treatment is topical antifungal and anti-inflammatory agents. Other broadly used therapies include lithium gluconate/succinate, coal tar, salicylic acid, selenium sulfide, sodium sulfacetamide, glycerin, benzoyl peroxide, aloe vera, mud treatment, phototherapy, among others. Alternative therapies have also been reported, such as tea tree oil, Quassia amara, and Solanum chrysotrichum. Systemic therapy is reserved only for widespread lesions or in cases that are refractory to topical treatment. Thus, in this comprehensive review, we summarize the current knowledge on SD treatment and attempt to provide appropriate directions for future cases that dermatologists may face.

Acute mucocutaneous methotrexate toxicity with marked tissue eosinophilia

Methotrexate toxicity in mucocutaneous areas is usually not associated with tissue eosinophilia. We describe a case of acute methotrexate-induced mucocutaneous erosions with interface dermatitis and eosinophils. A 76-year-old African-American woman with a history of bullous pemphigoid on methotrexate therapy presented with lower extremity cellulitis, developing oral and cutaneous erosions during hospitalization after daily dosage of methotrexate. Shallow circular cutaneous erosions were found on chest, abdomen and limbs. Laboratory results showed pancytopaenia and elevated liver function tests. Skin biopsy revealed irregular acanthotic epidermis with interface dermatitis, individual dyskeratotic cells and superficial perivascular lymphocytic infiltrate with numerous eosinophils. Methotrexate was stopped and leucovorin was administered, leading to improvement. The histopathological changes in acute mucocutaneous toxicity range from pauci-inflammatory erosions with dyskeratotic keratinocytes to interface dermatitis and infrequently seen eosinophils. This case exemplifies that interface dermatitis with a marked eosinophilic infiltrate can be found in the setting of acute mucocutaneous methotrexate toxicity.