Future directions in managing aniridia-associated keratopathy

Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies.     

The impact of sensory neuropathy and inflammation on epithelial wound healing in diabetic corneas

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes, with several underlying pathophysiological mechanisms, some of which are still uncertain. The cornea is an avascular tissue and sensitive to hyperglycemia, resulting in several diabetic corneal complications including delayed epithelial wound healing, recurrent erosions, neuropathy, loss of sensitivity, and tear film changes. The manifestation of DPN in the cornea is referred to as diabetic neurotrophic keratopathy (DNK). Recent studies have revealed that disturbed epithelial-neural-immune cell interactions are a major cause of DNK. The epithelium is supplied by a dense network of sensory nerve endings and dendritic cell processes, and it secretes growth/neurotrophic factors and cytokines to nourish these neighboring cells. In turn, sensory nerve endings release neuropeptides to suppress inflammation and promote epithelial wound healing, while resident immune cells provide neurotrophic and growth factors to support neuronal and epithelial cells, respectively. Diabetes greatly perturbs these interdependencies, resulting in suppressed epithelial proliferation, sensory neuropathy, and a decreased density of dendritic cells. Clinically, this results in a markedly delayed wound healing and impaired sensory nerve regeneration in response to insult and injury. Current treatments for DPN and DNK largely focus on managing the severe complications of the disease. Cell-based therapies hold promise for providing more effective treatment for diabetic keratopathy and corneal ulcers.     

Acquired acrodermatitis enteropathica due to zinc‐depleted parenteral nutrition

Well‐known causes of zinc deficiency, also referred to as acrodermatitis enteropathica (AE), include defects in intestinal zinc transporters and inadequate intake, but a rare cause of acquired zinc deficiency discussed here is an iatrogenic nutritional deficiency caused by parenteral nutrition administered without trace elements. While zinc‐depleted parenteral nutrition causing dermatosis of acquired zinc deficiency was first reported in the 1990s, it is now again relevant due to a national vitamin and trace element shortage. A high index of suspicion may be necessary to diagnose zinc deficiency, particularly because early clinical findings are nonspecific. We present this case of acquired zinc deficiency in a patient admitted to a pediatric intensive care unit for respiratory distress and atypical pneumonia, who subsequently developed a severe bullous eruption due to iatrogenic zinc deficiency but was treated effectively with enteral and parenteral zinc supplementation, allowing for rapid re‐epithelialization of previously denuded skin.     

Evaluation of corneal biomechanical properties in mustard gas keratopathy

Background

Degenerative biomechanical factors and immunologic processes with effect on collagen and corneal reparative process are known as the main cause of ocular surface dysfunction in mustard gas keratopathy (MGK) and may cause changes in the corneal biomechanical values. Therefore, we evaluate corneal biomechanical properties of these patients.

Amniotic Membrane Transplant for Bullous Keratopathy: Confocal Microscopy & Anterior Segment Optical Coherence Tomography

Purpose: To assess amniotic membrane retention after amniotic membrane transplant in bullous keratopathy patients and whether there were any corneal structural changes that may hinder further penetrating keratoplasty

Methods: A retrospective study including 22 patients who have undergone amniotic membrane transplant from 1 Jan 1998 till 30 Jun 2016. Confocal microscopy and anterior segment optical coherence tomography (ASOCT) were performed to assess the retention of amniotic membrane and to detect any corneal structural changes. The comparison was made with 5 controls who had bullous keratopathy awaiting endothelial keratoplasty.

Results: Patients had a mean follow-up of 61 ± 33.7 months. Pain reduction was significant (p < .001) although it did not significantly correlate with the regularity of the superficial, intermediate or basal epithelial layers, nor with the retention of the amniotic membrane. No long-term structural changes that may hinder future penetrating keratoplasty were detected.

Conclusion: This procedure is a safe and effective long-term treatment for symptomatic bullous keratopathy patients.     

Successful treatment of hemorrhagic bullous Henoch‐Schonlein purpura with intravenous immunoglobulins

Henoch‐Schonlein purpura (HSP) is the most common systemic vasculitis in childhood. There is no consensus about the management for isolated cutaneous manifestations in HSP. We describe a case of HSP presenting with severe skin lesions that did not respond to standard therapy with corticosteroids. The 11‐year‐old child was treated with intravenous immunoglobulins, which induced rapid and persistent resolution of symptomatology.     

Bullous pemphigoid induced by vildagliptin: a report of three cases

To report three cases of bullous pemphigoid in patients treated with vildagliptin. Case 1: An 86‐year‐old woman presented with bullous pemphigoid after 1 month of treatment with vildagliptin and metformin. After introduction of clobetasol, the symptoms resolved although vildagliptin was continued. However, the skin lesions reappeared 3 months later. Sustained remission was achieved only after definitive withdrawal of vildagliptin. Case 2: A 79‐year‐old man presented with bullous pemphigoid after 37‐month treatment with gliclazide, vildagliptin and metformin. The disease at first responded to clobetasol but 3 months later the lesions reappeared. They finally regressed when the gliptin was discontinued. Case 3: A 77‐year‐old woman, treated with gliclazide and vildagliptin for 26 months, presented with bullous pemphigoid, which responded well to discontinuation of the gliptin and topical clobetasol. Gliptins are new molecules for treatment of type 2 diabetes mellitus, which have been suspected of implication in bullous pemphigoid. Such cases have been described in the literature (seven with vildagliptin and three with sitagliptin). In nine of these cases, the gliptin was associated with metformin, but the latter had never been considered responsible. The mechanism implicated in the development of bullous pemphigoid has not yet been clearly identified, but may involve a modified immune response or alteration of the antigenic properties of the epidermal basement membrane. These reports support the risk of bullous pemphigoid in patients exposed to gliptins.     

诱导性协同共刺激分子及程序性死亡受体1在大疱性类天疱疮皮损中的表达及意义

【摘要】 目的 通过检测滤泡辅助性T细胞（Tfh）相关分子诱导性共刺激分子（ICOS）及程序性死亡受体1（PD?1）在大疱性类天疱疮（BP）患者皮损中的表达，探讨Tfh在BP发病机制中的作用。方法 收集大连市皮肤病医院2014—2017年间确诊的BP患者石蜡组织标本21份，其中女7例，男14例，平均年龄72.57岁。应用免疫组化SP法检测BP皮损中ICOS与PD?1的表达，以10例正常皮肤组织作为对照组。结果 ICOS、PD?1在BP皮损中均主要表达于表皮基底层、棘细胞层、颗粒层、角质层，以棘细胞层表达最为显著，细胞质、细胞核均见表达，偶见细胞膜表达，真皮层炎症细胞中亦有表达；正常皮肤组织中ICOS、PD?1表达少见。BP组ICOS表达率为85.71%（18/21），PD?1表达率为47.62%（10/21），均高于正常对照组（均为0），差异有统计学意义（P值分别＜0.001、＜0.05）。结论 Tfh细胞相关分子ICOS、PD?1在BP发病机制中可能发挥重要作用。