Incontinentia pigmenti with painful subungual tumors: a two-generation study

Phänotypisches und genetisches Spektrum von Incontinentia pigmenti – eine große Fallserie

HINTERGRUND

Incontinentia pigmenti ist eine seltene X-chromosomal dominant vererbte Systemerkrankung, die vor allem die Haut, aber auch andere neuroektodermale Gewebe wie Zähne, Haare, Augen und das zentrale Nervensystem betrifft.

PATIENTEN UND METHODIK

Diese multizentrische Fallserienstudie wurde an drei europäischen Hautkliniken durchgeführt und umfasste 30 Patienten mit Incontinentia pigmenti. Zwanzig Patienten wurden klinisch und genetisch untersucht, weitere zehn nur genetisch.

ERGEBNISSE

Die Studie umfasste 28 Frauen und zwei Männer mit einem medianen Alter von drei Jahren. Kutane Manifestationen zeigten sich bei allen 20 Patienten mit klinischen Daten. Stadium I wurde in 90 % dieser Patienten beobachtet. Stadium IV wurde bereits im Alter von einem Jahr beobachtet. Zahn- (81 %), Haar- (78 %) und neurologische Anomalien (53 %) waren häufiger als in bisherigen Berichten. Vierzehn Hautbiopsien zeigten typische Merkmale des entsprechenden Stadiums. Genetische Tests wurden bei 24 Patienten durchgeführt, von denen 14 die häufige Exon 4-10-Deletion und sieben andere pathogene Varianten aufwiesen, darunter drei unveröffentlichte Mutationen. In drei weiteren Fällen wurden keine genetischen Veränderungen gefunden.

SCHLUSSFOLGERUNGEN

In dieser Studie reichte der Phänotyp von lediglich subtil ausgeprägter Hautbeteiligung bis hin zu schweren Multisystemerkrankungen. Die extrakutane Beteiligung sollte zum Zeitpunkt der Diagnose und in regelmäßigen Abständen evaluiert werden, da sich einige Manifestationen erst mit der Zeit entwickeln.

SUMMARY

Background and objectives Incontinentia pigmenti is a rare X-linked dominantly inherited systemic disease affecting primarily the skin but also other neuroectodermal tissues such as teeth, hair, eyes, and the central nervous system. Patients and methods This multicenter case series study was conducted at three European departments of Dermatology including 30 patients with incontinentia pigmenti. Twenty patients were evaluated clinically and genetically, another ten only genetically. Results The study included 28 females and two males with a median age of three years. Cutaneous manifestations were present in all 20 patients with clinical data. Stage I was observed in 90 % of those patients. Stage IV was observed as early as one year of age. Dental (81 %), hair (78 %) and neurological anomalies (53 %) were more frequent than previously reported. Fourteen skin biopsies showed typical features of the corresponding stage. Genetic testing of 24 patients revealed the common exon 4-10 deletion in 14 cases and seven other pathogenic variants, including three unpublished mutations. In another three cases, no genetic alterations were found. Conclusions In this study, the phenotype ranged from only subtle cutaneous involvement to severe multisystemic disorders. Extracutaneous involvement should be evaluated at the time of diagnosis and in regular intervals, as some manifestations may develop over time.

Phenotypic and genetic spectrum of incontinentia pigmenti - a large case series

BACKGROUND AND OBJECTIVES

Incontinentia pigmenti is a rare X-linked dominantly inherited systemic disease affecting primarily the skin but also other neuroectodermal tissues such as teeth, hair, eyes, and the central nervous system.

PATIENTS AND METHODS

This multicenter case series study was conducted at three European departments of Dermatology including 30 patients with incontinentia pigmenti. Twenty patients were evaluated clinically and genetically, another ten only genetically.

RESULTS

The study included 28 females and two males with a median age of three years. Cutaneous manifestations were present in all 20 patients with clinical data. Stage I was observed in 90 % of those patients. Stage IV was observed as early as one year of age. Dental (81 %), hair (78 %) and neurological anomalies (53 %) were more frequent than previously reported. Fourteen skin biopsies showed typical features of the corresponding stage. Genetic testing of 24 patients revealed the common exon 4-10 deletion in 14 cases and seven other pathogenic variants, including three unpublished mutations. In another three cases, no genetic alterations were found.

CONCLUSIONS

In this study, the phenotype ranged from only subtle cutaneous involvement to severe multisystemic disorders. Extracutaneous involvement should be evaluated at the time of diagnosis and in regular intervals, as some manifestations may develop over time.

Pathology of the Nail Unit

This article discusses the histologic findings in key nail unit diseases, including inflammatory, infectious, and neoplastic conditions. The emphasis is on clinicopathologic correlates, best practices to demonstrate the relevant histopathologic features, and pitfalls in diagnosis. Understanding the pathology of these disorders enhances clinical acumen and may affect the choice of biopsy procedures and treatment measures, with the outcome of better clinical care for patients with nail disease.

Keratoacanthoma-Like Growths of Incontinentia Pigmenti Successfully Treated with Intralesional Methotrexate

We report the case of a 17-year-old girl with incontinentia pigmenti who developed multiple large hyperkeratotic tumors within Blaschkoid hyperpigmented patches on her left leg. Biopsy demonstrated an endoexophytic nodule with irregular invaginations of keratinizing squamous epithelium and a central keratin-filled crater, consistent with keratoacanthoma-like lesions of incontinentia pigmenti. The tumors were successfully treated with intralesional methotrexate.

'Hints' in the horn: diagnostic clues in the stratum corneum

The stratum corneum or horny layer is the uppermost layer of the epidermis, and is mainly responsible for the skin's barrier function. In spite of its complexity at the ultrastructural and molecular level, the features accessible to visualization on conventional histology are relatively limited. Nevertheless, knowledge of subtle clues that one may observe in the stratum corneum can prove useful in a wide range of situations in dermatopathology. We herein review a selection of common and rare entities in which the horny layer may reveal significantly important hints for the diagnosis. These clues include parakeratosis and its different patterns (focal, confluent, alternating, associated with spongiosis, epidermal hyperplasia or lichenoid changes), subcorneal acantholysis, infectious organisms in the stratum corneum (including fungal, bacterial and parasitic), thickening or thinning of the stratum corneum and the presence of different kinds of pigment. Even when normal, the horny layer may prove to be useful when seen in association with severe epidermal damage, a combination of features testifying to the acute nature of the underlying pathological process.

Dermatologic Manifestations of the Lower Extremity: Nail Surgery

Nail surgery is a fundamental component of podiatric surgery. Nail disorders are common and may cause significant morbidity and occasionally mortality. Diagnosis of inflammatory and infectious conditions, and of benign or malignant tumors, often requires a biopsy of the nail unit. Excisional surgery may also be curative for certain tumors. This article reviews key elements of nail anatomy, surgical preparation, local anesthesia, and methods to achieve and maintain a bloodless field. A familiarity with these concepts should allow clinicians to develop a surgical plan and approach when patients present with a nail disorder requiring biopsy or surgical treatment.

Keratoacanthoma (KA): An update and review

Keratoacanthoma (KA) is a common but underreported tumor of the skin. Two striking features of KA are its clinical behavior with spontaneous regression after rapid growth and its nosological position on the border between benignity and malignancy. We review current knowledge on the clinical, histopathological, and dermoscopic features of KA to ensure a proper diagnosis and describe its variants, including different types of multiple KAs. We highlight current concepts of KA ethiopathogenesis with special emphasis on the genetic background of multiple familial KA, the role of Wnt signaling pathway, and induction of KA by BRAF inhibitors and procedures of esthetic dermatology. Finally, treatment strategies are presented with surgical excision as a first option, followed by other modalities, including intralesional chemotherapy, topical and systemic agents, lasers, cryotherapy, and photodynamic therapy.

Incontinentia pigmenti

Incontinentia pigmenti is a rare genodermatosis in which the skin involvement occurs in all patients. Additionally, other ectodermal tissues may be affected, such as the central nervous system, eyes, hair, nails and teeth. The disease has a X-linked dominant inheritance pattern and is usually lethal to male fetuses. The dermatological findings occur in four successive phases, following the lines of Blaschko: First phase - vesicles on an erythematous base; second phase - verrucous hyperkeratotic lesions; third phase - hyperchromic spots and fourth phase - hypochromic atrophic lesions.

Nail histopathology

The structure of the nail unit is complex and many dermatologists and dermatopathologists have an incomplete understanding of it. Familiarity with the anatomy and histology of this unit, however, is a key factor in improving the diagnostic yield of nail biopsy. Inflammatory or infectious conditions that affect the nail can have a marked impact on a patient's quality of life. A wide-ranging variety of tumors can also develop in this region and they may be life-threatening or require surgery that will result in functional defects. The author reviews the anatomy and histology of the nail unit as well as the basic histopathologic findings in the most common conditions affecting the nails.

Benign subungual tumors

A variety of benign and malignant processes may affect the subungual region; however, most are relatively rare lesions. We present a review of the current literature regarding benign tumors affecting the subungual region.

X-linked incontinentia pigmenti or Bloch-Sulzberger syndrome: a case report

Incontinentia pigmenti is a rare X-linked genodermatosis that affects mainly female neonates. Skin manifestations are the most common and occur in four quite distinct phases. A female infant presented vesiculobullous lesions on trunk and limbs, and a verrucous lesion on the right palm. Biopsy revealed eosinophil exocytosis and pigment incontinence, confirming the clinical hypothesis. Although uncommon, incontinentia pigmenti should be taken into consideration as a possible differential diagnosis when vesiculobullous and verrucous lesions are present in childhood.

The two-faced NF-kappaB in the skin

The role of the transcription factor NF-kappa B, particularly its coupling to inflammation and cancer, has generated considerable interest in recent years. NF-kappa B in the skin is crucial for morphogenesis and homeostasis. Perturbations in its activity are linked to developmental skin defects, inflammatory skin disease, and skin cancer. However, the most striking aspect of NF-kappa B function in the skin is its two-faced behavior--both activation and inhibition of the pathway causes inflammation. In this review, we focus on the role of NF-kappa B in the skin and summarize the current knowledge in the field arising from animal models as well as human disease studies.

Linear atrophoderma of Moulin together with leuconychia: a case report

Linear atrophoderma of Moulin has a distinctive disease pattern characterized by hyperpigmented atrophoderma and was described originally in 1992. It follows the line of Blaschko, and occurs without preceding inflammation, subsequent induration or scleroderma. The lesions usually develop during childhood or adolescence, and the prognosis is good. The diagnosis is made clinically and histopathologically. In our 18-year-old male patient, there were atrophic plaques unilaterally located on the trunk and arm, and white discoloration on all finger nails. Histopathological examination revealed epidermal atrophy together with disruption of collagen fibres.