Acne keloidalis nuchae in renal transplant patients receiving tacrolimus and sirolimus

Immune cells and associated molecular markers in dermal fibrosis with focus on raised cutaneous scars

Raised dermal scars including hypertrophic, and keloid scars as well as scalp-associated fibrosing Folliculitis Keloidalis Nuchae (FKN) are a group of fibrotic raised dermal lesions that mostly occur following cutaneous injury. They are characterized by increased extracellular matrix (ECM) deposition, primarily excessive collagen type 1 production by hyperproliferative fibroblasts. The extent of ECM deposition is thought to be proportional to the severity of local skin inflammation leading to excessive fibrosis of the dermis. Due to a lack of suitable study models, therapy for raised dermal scars remains ill-defined. Immune cells and their associated markers have been strongly associated with dermal fibrosis. Therefore, modulation of the immune system and use of anti-inflammatory cytokines are of potential interest in the management of dermal fibrosis. In this review, we will discuss the importance of immune factors in the pathogenesis of raised dermal scarring. The aim here is to provide an up-to-date comprehensive review of the literature, from PubMed, Scopus, and other relevant search engines in order to describe the known immunological factors associated with raised dermal scarring. The importance of immune cells including mast cells, macrophages, lymphocytes, and relevant molecules such as cytokines, chemokines, and growth factors, antibodies, transcription factors, and other immune-associated molecules as well as tissue lymphoid aggregates identified within raised dermal scars will be presented. A growing body of evidence points to a shift from proinflammatory Th1 response to regulatory/anti-inflammatory Th2 response being associated with the development of fibrogenesis in raised dermal scarring. In summary, a better understanding of immune cells and associated molecular markers in dermal fibrosis will likely enable future development of potential immune-modulated therapeutic, diagnostic, and theranostic targets in raised dermal scarring.

High Frequency of Obesity in Acne Keloidalis Nuchae Patients: A Hypothesis from a Brazilian Study

Acne keloidalis nuchae (AKN) is a chronic inflammatory condition that almost exclusively affects the occipital and nape areas. Although not completely understood, its etiopathogenesis seems to be multifactorial, including association with metabolic syndrome (MetS). Despite being commonly seen in patients with MetS, obesity per se as a possible related factor for AKN has yet to be studied. The aim of this study was to evaluate the relationship between obesity and AKN in a series of patients. Eight male patients, with a median age of 38 years (range 15–48), were included. Overweight/obesity was found in 8/8 (100%), with median BMI of 32.2 (range 27.7–43.85 kg/m²), including 2 patients with class 3 obesity. We hypothesize adipose tissue accumulation in the nape, the only moving part of the scalp, leads to redundant skin folds, more friction, and inflammation, triggering AKN. This paper highlights the possible relationship between AKN and overweight/obesity, hypothesizing a mechanism for their contribution to the etiopathogenesis of this scalp disorder. To the best of our knowledge, this is the first study focused specifically in this association. While general physicians should pay attention to the appearing of AKN in overweight/obese patients, dermatologists must be aware that AKN patients should be assessed beyond the skin.

Acne keloidalis nuchae in Asian: A single institutional experience

Acne keloidalis nuchae, a type of folliculitis involving the back of the neck, is common in black men, although rare cases have been reported in patients of other ethnicities. We analyzed the clinicopathological features of acne keloidalis nuchae in 17 Asians. Patients’ age at the time of presentation ranged from 20 to 69 years. Most patients experienced the disease over 2 years (range, 3 months–20 years); follow-up data were available for 11 (65%) patients (range, 2–95 months). Nine (53%) patients had comorbidities, but none had a history of other skin disease or a family history of acne keloidalis nuchae. Macroscopically, seven (41%) patients had multiple erythematous pustulopapular lesions, and 10 (59%) had a single large plaque. Histopathologically, deep scarring folliculitis containing naked hair shafts was identified. In all cases, inflammation was most severe in the upper two-thirds of the dermis, and the differences in pustulopapular and plaque lesions were more prominent in the peri-inflammation area. Of the seven patients with plaque lesions treated with steroids alone or steroids and cryotherapy, three experienced plaque reduction. Acne keloidalis nuchae occurring in Asian patients frequently present with typical clinicopathological features, and therefore in spite of very low incidence the diagnosis of this disease entity should be considered in idiopathic scarring folliculitis of the posterior neck.