Nails in systemic disease

Nail plate and nail unit abnormalities may be helpful as diagnostic tools or as a part of the puzzle for confirmation of systemic disease. There are specific and nonspecific nail signs, which can be seen involving one or more nails, that occur simultaneously or secondary to systemic disease. Occasionally these clues can be diagnostic, while most are nonspecific reaction patterns. Nail changes occur in the nail plate as a result of nail matrix abnormalities caused by systemic disease and other systemic insults such as reactions to medications. In this article we review some of the more common nail signs that can be used to help diagnose systemic disease.     

Pachyonychia Congenita Type I Presenting with Subtle Nail Changes

Abstract:   Pachyonychia congenita type I is an autosomal dominant disorder where nail abnormalities are a constant feature and develop during childhood. We report here a family with pachyonychia congenita type I and very mild nail changes to underline that this diagnosis should be considered even in the absence of severe nail thickening.     

甲扁平苔藓研究进展

甲扁平苔藓临床少见,可伴有皮肤扁平苔藓或独立存在.甲扁平苔藓的流行病学研究较少,其流行病学特点尚未完全阐明.甲扁平苔藓分5型:Ⅰ型为典型皮损伴有甲损害,Ⅱ型为不典型皮损伴有甲损害,Ⅲ型为头皮损害伴有甲损害,Ⅳ型为黏膜损害伴有甲损害,Ⅴ型为单纯甲损害.甲扁平苔藓有许多特征性临床表现,如翼状胬肉.临床上需与甲真菌病及其他可引起甲营养不良的疾病鉴别.甲扁平苔藓的组织病理特征与其他部位的扁平苔藓类似,皮肤镜有助于辅助诊断本病.本病治疗困难,缺少特效治疗方法.系统应用激素是唯一有循证研究支持的疗法.阿维A治疗甲扁平苔藓有效.甲氨蝶呤、环孢素等免疫抑制剂也可有效治疗甲扁平苔藓.甲扁平苔藓预后差,复发率高.     

Nail involvement in autoimmune bullous disorders

Autoimmune bullous disorders frequently cause nail abnormalities, particularly paronychia and onychomadesis. In pemphigus vulgaris (PV) nail abnormalities can even precede skin findings. Nail lesions often relapse just before generalized disease exacerbation or recurrence. Severe nail changes are often associated with extensive and severe disease. Fingernails are more commonly affected. A report in the literature associates hemorrhagic nail abnormalities with poor prognosis in patients with PV. Nail scarring and pterygium are a rare complication of bullous pemphigoid. Nail loss has been occasionally reported in epidermolysis bullosa acquisita.     

Treatment of inflammatory nail disorders

This article provides an updated review on diagnosis and treatment of inflammatory nail disorders including psoriasis, lichen planus, trachyonychia, and autoimmune bullous disorders. Despite the significant negative repercussion of the nail psoriasis in the quality of life of patients, treatment is often not sufficiently effective. The efficacy of topical therapies is limited to nail bed psoriasis. Intralesional corticosteroid injections are extensively utilized in nail matrix psoriasis. Systemic immunosuppressant drugs such as methotrexate and cyclosporine have shown efficacy. Biologics, particularly infliximab and etanercept, have also demonstrated high efficacy in the treatment of severe nail disease. Nail matrix lichen planus can cause nail atrophy and irreversible nail scarring and requires prompt treatment with systemic steroids. There is not gold standard therapy for trachyonychia, but in most cases the nail signs improve spontaneously and treatment is not necessary. Nail changes in pemphigus and other autoimmune disorders respond promptly to systemic therapy with steroids and immunosuppressants.     

Dermoscopy of non‐skin cancer nail disorders

Nail dermoscopy is becoming more and more frequently utilized for the diagnosis of nail disorders. It can be performed with handy dermoscope or with a video dermoscope, which allows magnifications of up to 200. Nail dermoscopy requires a good knowledge of nail anatomy and physiology and the pathogenesis of nail diseases: we have to know which part of the nail we have to look at! The nail is in fact not visible as a whole at one time, but its different parts should be observed, moving the lens back and forth and transversally. All nail disorders can be observed by dermoscopy. However, except for some diseases in which the technique really adds a lot to clinical examination, in most of the cases, nail dermoscopy only permits a better visualization of symptoms already evident to the naked eye. Dermoscopic features of nail signs are always very interesting and surprising, and may help in our understanding of nails.     

The nail in the elderly

Treating elderly patients has become common in daily clinical practice. Consequently, it is important to focus our interest on a neglected region: the nail area. Anatomy and physiology are indispensable for a good comprehension of some phenomenons. Histopathology of senile changes may explain some pathologic situations and is indispensable for diagnosing uncommon tumors. Chemical composition shows that a normal nail contains 18% water. The rate of linear nail decreases as age advances. Ridging is a normal finding on fingernails, with color varying from shades of yellow to grey. The most common disorders, however, are linked to repeated trauma, with sometimes ingrowing toenails with different appearances. Tumors in the nail area are relatively frequent. Nail fungal infection may be isolated or associated with conditions such as psoriasis and diabetes. The management of the main nail disorders observed in the elderly are presented.     

PATHOLOGY OF THE FINGER NAIL IN PSORIASIS

Summary.— Psoriasis of the finger nail produces metaplastic change of the nail matrix and nail bed to skin-like epithelium, following which the histological changes are essentially similar to those seen in the skin. The resulting lesions of the finger nail are of 2 types: (1) Nail plate abnormalities, the nature of which depends upon the site and the duration of disease in the matrix; (2) Nail bed abnormalities, consisting of onycholysis, subungual keratosis and splinter haemorrhages.     

Nail changes during childhood

Nail changes occur frequently in adults, but are relatively rare in children. There are, however, certain nail changes that emerge particularly during childhood. Ingrown nails, onychoschizia, congenital slanted alignment of the large toenail, and psoriasiform nail dystrophies can be frequently observed in toddlers and in schoolchildren the syndrome of an ingrown nail, nail artifacts, periungual warts or fibromas, trachyonychia, and nail mycoses. Connatal nail changes can appear as isolated events or together with other symptoms whereas acquired nail changes are caused by infections, traumatic injuries, or tumors, in conjunction with skin diseases or general illnesses, or even develop spontaneously.     

Genetics of human isolated hereditary nail disorders

Human hereditary nail disorders constitute a rare and heterogeneous group of ectodermal dysplasias. They occur as isolated and/or syndromic ectodermal conditions where other ectodermal appendages are also involved, and can occur associated with skeletal dysplasia. ‘Nail disorder, nonsyndromic congenital’ (OMIM; Online Mendelian Inheritance in Man) is subclassified into 10 different types. The underlying genes identified thus far are expressed in the nail bed and play important roles in nail development and morphogenesis. Here, we review the current literature on nail disorders and present a coherent review on the genetics of nail disorders. This review will pave the way to identifying putative genes and pathways involved in nail development and morphogenesis.     

斑秃患者2000例中甲病变的临床分析

我们对2000例斑秃（alopecia areata,简称AA）患者甲病变的临床表现，发生率及病理改变，进行了观察，并以2130例普通人群作为对照，结果AA的甲病变明显高于普通人群，尤其是全秃和普秃型的患者，甲病变以凹点和白点为最多，病理改变以聚集大量的角化不全细胞为主，本文还分析了甲病变与AA的病程及病情的关系。     

Nail changes in alopecia areata: an update and review

Nail changes are a common feature of alopecia areata (AA) and are a significant source of cosmetic disfigurement and functional impairment. This review provides an update of the prevalence, clinical and histopathological features, pathogenesis, differential diagnosis, clinical course, prognosis, and management of nail changes in patients with AA. Searches for peer‐reviewed journal articles were conducted using the PubMed/MEDLINE database with the search terms “nail changes alopecia areata,” “alopecia areata nails,” and specific searches on “trachyonychia alopecia areata” and “pitting alopecia areata.” Other sources of articles included the reference lists of retrieved articles. Nail changes are a common feature of AA, with an average prevalence of 30%, and can cause significant disfigurement and loss of function. Pitting and trachyonychia were by far the most common manifestations of AA, with an average prevalence of 20 and 8%, respectively. Red spotted lunulae, onycholysis, and punctate leukonychia were other reported findings. Other etiologies, such as onychomycosis or lichen planus, may coexist with or confound the diagnosis. There is limited published data on the clinical manifestations of AA‐associated nail changes and therapeutic options. Larger controlled trials are necessary to guide treatment decisions.     

The thyroid

The integument contains many components whose function is influenced by thyroid hormone. Thus, an increase or decrease in hormone levels results in a variety of cutaneous, hair, and nail changes. These changes are important to recognize, as they may aid in the early diagnosis of thyroid disorders. Other cutaneous disorders are more prevalent in patients with thyroid disease, and their recognition may likewise be helpful. Finally, several syndrome complexes occur with which thyroid disorders are regularly associated.     

Nail changes in patients with liver disease

Background Liver cirrhosis, hepatitis C virus (HCV) and hepatitis B (HBV) virus infections are known to be associated with different skin disorders. Nail changes are additional important criteria, which would help in identification of these systemic diseases. Objective To record the nail abnormalities in patients with liver disease which were not reported before, especially those with HCV and HBV infection. Patients and methods The study comprised 100 patients with HCV, HBV and liver cell failure, and 100 normal healthy controls. Both groups underwent full history taking and thorough general examination, complete blood picture, hepatitis B antigen, hepatitis C antibody, liver function tests, abdominal ultrasonography and PCR were performed in patients with liver disease. Full nail examination was performed. Results Nail changes were more prevalent in patient group (68%) than in the control group (35%). The nail infection, onychomycosis, was the most common finding in 18% of patients and that in controls was 10% followed by in a descending order, longitudinal striations, brittle nails, onychorrhexis, clubbing of fingers, dystrophic nails, leukonychia and longitudinal melanonychia. Conclusion Nail changes are observed with not only liver cirrhosis but also with HCV and HBV infection, and this will add additional clinical criteria for general practitioners and dermatologists to help them with diagnosis of these common systemic infections.     

Onychoscopy of non‐infectious nail abnormalities in patients after allogeneic haematopoietic stem cell transplantation

Nail abnormalities after allogeneic haematopoietic stem cell transplantation procedure (alloHSCT) are often reported. Usually, they are related to chronic graft‐versus‐host disease (cGvHD). So far, only clinical manifestations of selected nail abnormalities have been described, without the presentation of dermoscopic images. In this article, we present morphologic and dermoscopic manifestations of potential non‐infectious nail abnormalities in patients after alloHSCT procedure based on reviewed literature and our own experience with dermoscopic iconography. In majority of studies published till now, nail changes are not connected to severity of other cGvHD symptoms; however, e.g. the presence of pterygium inversum unguis may be an indicator of lung dysfunction. As nail changes may be an early sign of cGvHD and always present in association with other manifestations, routine clinical assessment should include nails examination. Knowledge of possible presentation of nail involvement after alloHSCT may be valuable for treating physician.     

Nail changes in epidermolysis bullosa: clinical and pathogenetic considerations

Nail changes in epidermolysis bullosa (EB) are common, but although they are highly suggestive of the disease, they are not pathognomonic. They are the result of abnormalities of the nail matrix and nail bed, associated with the pathogenetic alterations of the dermo-epidermal junction which occur in EB. In addition, secondary trauma in the areas of epidermal-dermal separation, and chronic inflammation of the nail matrix, are probable contributory factors, even in non-scarring forms of EB. Recent developments in the molecular and cell biology of the cutaneous basement membrane zone have greatly advanced our understanding of the pathomechanisms underlying different subtypes of EB. Defects in genes coding for the structural proteins of the basement membrane zone have been defined in some EB subtypes, and abnormal expression of structural proteins in others. The data accumulated from study of these genetic disorders will contribute to knowledge of the role of the dermo-epidermal junction in the normal physiology and differentiation of the nails, and be of value n discerning the aetiopathogenesis of acquired nail diseases.     

Clouston syndrome can mimic pachyonychia congenita

We studied three families suffering from nail abnormalities who had previously been diagnosed as pachyonychia congenita. No keratin gene mutations were detected. Sequencing of connexin 30 (GJB6 gene) in these patients identified heterozygous missense mutations G11R and A88V that are known to be associated with Clouston syndrome. This unexpected finding expands the Clouston syndrome phenotype and suggests that some patients diagnosed with pachyonychia may in fact be suffering from Clouston syndrome.     

Clinical study of nail changes in leprosy and comparison with nail changes in diabetic patients

Background Nail changes in leprotic patients are not specific to leprosy, and may be observed in other peripheral neuropathies. Diabetes is one of the diseases that present with nail dystrophy secondary to peripheral neuropathy, vasculopathy, trauma and infections. Therefore, nail changes in diabetic neuropathy are expected to be very similar to that of leprosy. Objectives To evaluate the frequency and pattern of nail changes in Egyptian leprotic patients with the different spectrums of the disease, and to compare nail changes in leprosy with those seen in patients with diabetic neuropathy. Methods The study included 115 leprosy patients and 60 patients with diabetic peripheral neuropathy. Nail examination was thoroughly carried out and various nail changes were recorded including the location of the involved nails (fingers, toes). Results Our study detected similar incidence of nail changes in both multibacillary (MB) (86%) and paucibacillary (PB) patients (86%). Flag sign (alternating horizontal bands of whitish and pinkish discoloration of the nail) observed in our study was not reported before. It was more commonly seen in MB patients (21%) than in PB patients (14%). Our results also revealed that the nail changes were more commonly seen in leprosy patients (86%) than in diabetic patients (68%). Conclusion Nail changes in leprosy are multifactorial, and could be related to one or more of the following: neuropathy, endarteritis, trauma, drugs or superimposed infections. Nail changes in leprosy may be used as an additional clue that helps in the diagnosis.     

An unusual case of factitious onychodystrophy

Nail disorders are a common dermatologic problem, and when such disorders are self-induced, the diagnosis and treatment can be challenging. We present an unusual instance of factitious onychodystrophy with associated erythronychia of the nail bed.     

Drug-induced nail abnormalities

This article reviews the different nail symptoms produced by drugs. Drug-induced nail abnormalities may result from toxicity to the matrix, the nail bed or the periungual tissues. The most common symptoms include Beau's lines/onychomadesis, melanonychia, onycholysis, and periungual pyogenic granulomas. Nail changes usually affect several nails and in most cases are asymptomatic. Drugs that most frequently produce nail abnormalities include retinoids, indinavir, and cancer chemotherapeutic agents. In this article, we also include nail adverse effects as a result of radiotherapy since they are commonly observed in clinical practice.