Musculoskeletal and nail ultrasound findings in children with psoriasis: a case-control study.

FOXN1 Is Critical for Onycholemmal Terminal Differentiation in Nude (Foxn1nu) Mice

Dear Editor: The nail unit is one of the most specialized organs in the body and composed of specialized epithelial tissue, which includes the nail matrix, nail bed, nail plate, and specialized mesenchymal tissue. The nail plate mainly originates from the nail matrix and is firmly attached to the nail bed, which may contribute to formation of the nail plate1. The specialized nail mesenchyme-onychodermis-is located below the nail matrix and nail bed and differs from the skin dermis2. Subungual melanoma (SUM) is an uncommon variant of melanoma that occurs in the nail unit. It usually arises from the nail matrix but may involve other components of the nail unit, such as the proximal nail fold, nail matrix, nail bed, and hyponychium3. As SUM progresses in the nail unit, it tends to spread into the nail bed, hyponychium, and proximal nail fold, with the clinical presentation of Hutchinson's sign4. Previously, Izumi et al.4 reported that in early SUM proliferation, atypical melanocytes are more prominent in the hyponychium than in the nail bed or nail matrix. However, the frequency of dermal invasion in each part of the nail unit and progression pattern of SUM is not yet known. Here, we report a case of SUM showing tumor invasion with sparing of the nail matrix dermis. A 51-year-old man presented with a pigmented lesion on his finger, which persisted for 8 years. Skin examination showed total melanonychia with dark brown macules around the 4th fingernail (Fig. 1A). Although we recommended biopsy, the patient did not comply with it. Approximately 6 months later, he returned to our department with a large tumor on the 4th finger (Fig. 1B). However, the nail deformity was not apparent even with the presence of a large tumor with black pigmentation and smaller tumors on the skin of the 4th finger. Punch biopsy from the tumor revealed invasive melanoma. The patient was transferred to the Department of Plastic Surgery, and the finger was amputated. Subsequently, several sections were taken for evaluation of the finger specimen. Transverse sections on the proximal nail matrix showed melanoma in situ without dermal invasion (Fig. 1C, D). A transverse section through the nail plate showed melanoma in situ on the nail bed and large invasive melanoma on the lateral side of the finger (Fig. 1E). Fig. 1 (A) The patient presents with total melanonychia and dark brown macules around the 4th fingernail. (B) Six and a half months later, he shows a large tumor on the 4th finger without any definite nail deformity. Line C and line E indicate each section orientations ... Clinically, SUM presents as melanonychia in the early stages, but may be associated with nail deformity in the later stages5. In our case, the nail deformity was not clinically definite, even with the presence of a large tumor on the skin around the nail. Histopathologically, dermal invasion in the nail matrix area was not noted despite the presence of a protruding large invasive melanoma on the lateral side of the finger. The nail matrix is a germinative and proliferative compartment, and its cells have the property of upward growth to produce the nail plate, making invasion of the matrix difficult. This may explain the absence of dermal invasion in the nail matrix area in our case. Our findings suggests that dermal invasion of SUM in the nail matrix area may be much less or occur later as compared to that in other areas of the nail unit. A previous study on SUM reported a case in which the nail matrix was spared in dermal invasion4. In our case, the absence of dermal invasion in the nail matrix area and nail bed may be related to the presence of onychodermis (specialized nail mesenchyme) below the nail matrix and nail bed in the nail unit. Further studies are needed to clarify the progression of SUM in association with dermal invasion.

Background and Aims:Melanonychia can be a manifestation of benign or malignant pathology and often poses a diagnostic challenge on clinical examination. Even with distinguishing dermoscopic features (nail plate), it can be quite difficult to determine the nature of pigmentation as complete assessment of nail bed and matrix is still not possible. Intraoperative dermoscopy (IOD) can serve as a useful tool to appreciate the bed and matrix changes. The aim here is to study the intraoperative dermoscopic features in patients with melanonychia and correlate with histopathology.Methods:20 consecutive patients with melanonychia were recruited. Inclusion criteria was melanonychia of sudden onset, progressive nature, irregular width/color/symmetry on dermoscopy, positive Hutchinson sign, solitary nail involvement or associated nail dystrophy. Preoperative dermoscopy was performed and recorded. Patients were planned for nail matrix biopsy, during which IOD was performed over nail matrix and bed after removal of the nail plate. Images were recorded and analyzed and correlated with the histopathology.Results:Out of 20 patients, 12 were females and 8 males. On IOD-histopathological correlation, 2 patients were found to have melanoma of the nail unit, 5had nail lichen planus, 9 had benign melanocytic nevi, and 4 had fungal melanonychia. IOD revealed fine, parallel and regular lines of pigmentation localized to proximal nail bed and matrix in all patients with benign melanonychia, while dark thick bands with irregular borders, dots, globules, streaks and structureless areas in the two patients with melanoma. Fungal melanonychia revealed an unremarkable nail bed and matrix on IOD.Conclusion:Intraoperative dermoscopycan help in determining the nature of melanonychia and obviate the need to perform biopsy in certain cases. It can also aid in delineating the most suitable site for biopsy, along with grossly assessing the extent of involvement in case of malignancy.

BackgroundOther spectral Doppler parameters can assess joint impairment caused by psoriatic arthritis and psoriasis1.ObjectivesTo detect and compare Doppler velocimetric indexes changes in 3 groups of patients.MethodsThirty – eight patients were...

BackgroundNail psoriasis occurs frequently in patients with psoriatic disease, it can lead to functional impairment, pain, discomfort, decreased quality of life and can also be a predictor for the development of arthritis. Early recognition of this condition can provide early and effective treatment and prevent structural impairment. This study aims to identify nail ultrasonographic characteristics in three groups: psoriasis (PsO), psoriatic arthritis (PsA) and controls patients, to determine if the ultrasonography (US) can identify early signs of nail psoriatic impairment or local inflammation. We conducted nail US to determine nail matrix resistance index (NMRI), nail bed resistance index (NBRI), and power Doppler (PD) and grayscale (GS) parameters in these 3 groups.MethodsSingle-center, cross-sectional study. GS, PD, and spectral doppler images of bilateral 2nd and 3rd fingernails were acquired from 35 PsO, 31 PsA, and 35 controls patients. An US equipment with an 18 MHz linear transducer for GS and 8.0 MHz for PD was used. PD, NMRI, NBRI, nail plate thickness (NPT), nail bed thickness (NBT), nail matrix thickness (NMT), and morphostructural characteristics of the trilaminar structure (TS) were evaluated in saved images, blind.ResultsMean NMRI and NBRI did not differ between groups. Linear regression analysis detected no relationships between PsO or PsA and NMRI or NBRI. Nail PD grade did not differ between groups. Type I and IV TS changes were more frequent in PsO; types II and III changes were more frequent in PsA (p < 0.001). NPT was greater in PsA and PsO groups than controls: PsA 0.73 ± 0.14 mm, PsO 0.72 ± 0.15 mm, Controls 0.67 ± 0.10 mm (p = 0.001).ConclusionEchographic TS characteristics of the nail plate and NPT evaluated by GS are useful and can distinguish PsO and PsA nails from controls. NMRI, NBRI, and US nail microcirculation parameters could not distinguish psoriatic nails.Trial registration72762317.4.0000.5327 (Certificate of Presentation of Ethical Appreciation – CAAE - Plataforma Brasil) Avaiable in https://plataformabrasil.saude.gov.br/login.jsf.

Subungual melanoma with blue naevus-like morphological features: a clinicopathological retrospective analysis of nine cases

Surgical Pearl: Hemostat-assisted nail avulsion revisited

The nail unit (unguis, onyx=nail) consists of four epidermal structures: nail matrix, nail bed,hyponychium,and the proximal nail fold. The bony phalanx is part of the nail apparatus. The nail sits between the proximal and lateral nail grooves,which are invaginations of the corresponding nail folds. Size and shape of the distal bone, the nail plate, and the periungual tissue make up the final form of the nail. The nail plate is produced by the nail matrix, which extends 3-6 mm under the proximal nail fold; its distal part is visible as a white semicircular structure, the lunula. The proximal nail fold is attached to the nail plate, usually sealing this cul-de-sac. The nail plate continually slides over the nail bed to which it is firmly attached. The nail bed is richly vascularized and contains glomus organs. The nail plate is translucent, revealing the pink-colored nail bed. Transmission of radiation depends on the wave length and thickness of the nail plate. Approximately less than 1%-3% of UV B, some 5%-10% of UV A, but 10%-20% of visible light pass through a normal nail plate. Distal to the nail bed is the hyponychium, which represents an extension of the epidermis under the nail plate and ends at the distal groove.

Background The early diagnosis of psoriatic arthritis (PsA) on patients with psoriasis (PsO) is challenging, but may prevent functional impairment. Patients with nail psoriasis have an odds ratio of nearly 3.0 of developing psoriatic arthritis. Ultrasonography is a replicable, radiation-free method that could be used to identify nail changes before clinical manifestations. Objectives To verify if nail changes identified via ultrasonography can differentiate between PsA and PsO patients as well as between PsA/PsO patients and a control group. Methods Single-center, cross-sectional study. PsA patients were consecutively enrolled, PsO and controls were matched by age and gender with the PsA group. PsO patients must have had the diagnosis of psoriasis of any subtypes. PsA patients had to fulfill the CASPAR criteria. Exclusion criteria, for all groups included: other joint inflammatory disease; dermatological or systemic disease that could modify the nail structure. Ultrasound examination was performed using a MyLab 50 system (Esaote Biomedica, Genova, Italy), equipped with a linear probe of 18 MHz in greyscale (GS) and 8.0 MHz in power doppler (PD). The exams were performed in a room with temperature between 22°C and 26°C, after a 10 minutes rest period. Patients were seated, with hands and fingers in a neutral position over the table. The nails were scanned on a longitudinal plane. The 2nd and 3rd fingernails of both hands were examined. Through GS, the following characteristics were assessed: 1) the trilaminar appearance of the nail plate (NP), that was classified according to Wortsman characterization of changes on psoriatic nails (I – IV), 2) the nail plate thickness (NPT), 3) the nail bed thickness (NBT), and 4) the nail matrix thickness (NMT). The signal of PD in the nail matrix and in the nail bed were evaluated together and classified according to Gutierrez et al.’s score (1-3). Comparisons between independent means were analyzed using ANOVA or Kruskal-Wallis test. The association between categorical variables was calculated by chi-squared test or Fisher’s exact test. Results In the trilaminar structure (TS) evaluation, 137(99.3%) of the nails from control group had no change in the TS; for PsO group, 32 of the analyzed nails presented TS alterations, as follows: 9 type I, 5 type II, 7 type III and 11 type IV. For PsA group, there were also 32 of the analyzed nails that presented TS changes; 4 type I, 15 type II, 9 type III and 4 type IV. The mean NPT± SD (mm) was higher on both PsA and PsO groups when compared to the control group: 0.73 ±0.14 and 0.72 ±0.15 vs.0.67±0.10 (p=0.001), respectively. NBT and NMT means did not differ among groups. There was also no statistical difference between groups regarding the degree of nail PD, as well as no difference in the grayscale and PD evaluated parameters between PsA/PsO nails both with or without clinical involvement. Conclusion Alterations of the trilaminar structure of the NP and the NPT show differentiation between psoriatic nails and the control group, but no differentiation between PsO and PsA nails. PD, NMT and NBT means also had no differences between groups. Studies with larger sample sizes are necessary to clarify the utility of these parameters in the evaluation of psoriatic patients.

Aim of the Study The aim of the study was to conduct an ultrasound (US) assessment of changes in fingernails in psoriatic patients with nail involvement. Material A total of 69 patients with psoriatic changes in nails participated in the study, including 38 patients with psoriasis (Ps) and 31 with psoriatic arthritis (PsA) and 30 people in the control group. A total of 988 nails were examined. Results The thickness of the nail plate, nail bed, and matrix as shown in an ultrasound examination increased with the mNAPSI index (r=0.328, p=0.021; r=0.219, p=0.036; and r=0.422, p=0.011, respectively). The thickness of nail plate, bed, and matrix in patients with onycholysis and hyperkeratosis-type changes (concomitant or present separately) was significantly greater than when only pitting-type changes occurred (p=0.007, p=0.035, and p=0.023, respectively). An examination of nails with only pitting-type changes showed an increase in the matrix thickness compared to the control group (p=0.018). The focal hyperechoic involvement of the dorsal plate (80%) was the change most often observed in an US examination in Ps patients, whereas loosening of the borders of the ventral plate was most often observed in PsA patients. The thickness of nail bed in PsA patients increased with the duration of arthritis (r=0.399, p=0.022) and was correlated with the number of swollen digits (r=0.278, p=0.041). Conclusions The findings of this study may indicate an association of an inflammation in the nail bed with PsA development. Apart from a direct assessment of the described morphological changes of nails, a US examination could prove useful in an assessment of intensity of a local inflammation as a prognostic factor for PsA development.

Nail abnormalities occur in all age groups but are more prevalent in older adults. Nail disorders account for 10% of dermatologic disorders. Nail abnormalities can be categorized as surface texture irregularities, color changes, defects of nail plate attachment/nail shedding, tumors, or a combination of these. Brittle nails affect up to 20% of the population but are most prominent in older women and on fingernails. Different patterns of brittle nails can be seen in the same patient or can coexist in the same nail. Beau lines are transverse grooves caused by decreased keratinocyte activity in the proximal nail matrix. Nail pitting is due to abnormal keratinization in the proximal nail matrix. More than one-half of patients with psoriasis will have some nail involvement, and pitted nails are just one manifestation of nail psoriasis. Color changes may appear in the nail plate, nail bed, or nail matrix. In the nail unit, melanocytes are located only in the nail matrix. Brown-black nail changes are known as melanonychia and are caused by melanocyte activation or proliferation. Melanoma typically presents as longitudinal brown-black nail lines, but in approximately 30% of cases, it may present as a nail mass. Abnormal growth in the nail unit should raise concern for benign or malignant tumors, including the most common malignant tumor, squamous cell carcinoma. Nail clippings, ultrasonography, dermoscopy, and biopsy are useful for the diagnosis of nail abnormalities. Dermoscopy can assist in triaging lesions and differentiating those that can be safely observed from those that should be biopsied.

BackgroundClinical physical examination can detect superficial nail changes in psoriatic patients. However, the nail matrix and bed are not accessible for clinical assessment. Recently, ultrasonography (US) has emerged as a...

Incorporation of Thymidine-Methyl-H3 and Glycine-2-H3 in the Nail Matrix and Bed of Humans

Subungual acantholytic dyskeratotic acanthoma: an unusual cause of longitudinal erythronychia

Chapter 44 - Nail Signs of Systemic Disease