Nail Matrix Research Articles

Onychomatricoma in the Light of the Microanatomy of the Normal Nail Unit

Onychomatricoma (OM) is an uncommon benign tumor of the nail thought to exhibit differentiation limited toward the nail matrix. Four recent articles from our laboratory have shown, in some respect, a morphological and immunohistochemical homology between the nail unit and the hair follicle at the level of the matrix and isthmus. The purposes of this article are as follows: to investigate whether the sequential pattern of hair keratin expression in the normal nail matrix is maintained in OM, to compare and contrast follicular tumors with matrix differentiation in OM, and to furnish morphological and immunohistochemical markers of the onychogenic capacity of OM. Formalin-fixed paraffin sections from 6 OM were examined using specific keratin (K) antibodies for the matrix, nail bed, and nail isthmus. Hair keratins were expressed in a sequential pattern similar to normal nail matrix. In 3 cases where the cavities were completely lined by the fibroepithelial projections, the morphological aspect and the pattern of expression of K5, K17, K6, K16, and K75 suggested a differentiation toward the nail bed and the nail isthmus. This study shows for the first time that OM can recapitulate the entire nail unit with differentiation toward the nail bed and the nail isthmus. We have identified new histopathological and immunohistochemical features in OM, and we have abridged the diversity of its histological presentation in 2 main patterns: a lobulated or foliated pattern, observed principally on transverse section, and a "glove-finger" mono- or multidigitate pattern, observed mainly on longitudinal section. We have also concluded that OM is not a nail variant of trichoblastoma, pilomatricoma, or other pilar tumors. The concept of epithelial onychogenic tumor with onychogenic mesenchyme could shed more light about the true nature of this peculiar mixed tumor. However, the term OM is short and sanctioned by usage, which justifies keeping it.

The Nude Mutant Gene Foxn1 Is a HOXC13 Regulatory Target during Hair Follicle and Nail Differentiation

Among the Hox genes, homeobox C13 (Hoxc13) has been shown to be essential for proper hair shaft differentiation, as Hoxc13 gene-targeted (Hoxc13(tm1Mrc)) mice completely lack external hair. Because of the remarkable overt phenotypic parallels to the Foxn1(nu) (nude) mutant mice, we sought to determine whether Hoxc13 and forkhead box N1 (Foxn1) might act in a common pathway of hair follicle (HF) differentiation. We show that the alopecia exhibited by both the Hoxc13(tm1Mrc) and Foxn1(nu) mice is because of strikingly similar defects in hair shaft differentiation and that both mutants suffer from a severe nail dystrophy. These phenotypic similarities are consistent with the extensive overlap between Hoxc13 and Foxn1 expression patterns in the HF and the nail matrix. Furthermore, DNA microarray analysis of skin from Hoxc13(tm1Mrc) mice identified Foxn1 as significantly downregulated along with numerous hair keratin genes. This Foxn1 downregulation apparently reflects the loss of direct transcriptional control by HOXC13 as indicated by our results obtained through co-transfection and chromatin immunoprecipitation (ChIP) assays. As presented in the discussion, these data support a regulatory model of keratinocyte differentiation in which HOXC13-dependent activation of Foxn1 is part of a regulatory cascade controlling the expression of terminal differentiation markers.

Immunohistochemical Study of 40 Cases of Longitudinal Melanonychia

The etiology of longitudinal melanonychia (LM) is difficult to establish by clinical and dermoscopic examinations alone. Microscopic examination of the nail matrix remains crucial. Two groups of LM may be identified: melanocytic activation (melanic pigmentation of the matrix epithelium without any increase in the density of melanocytes) and melanocytic proliferation (lentigo, nevus, or melanoma). The histological examination is challenging, and immunohistochemical investigations can be helpful. The objective of this study was to analyze the immunohistochemical findings with routinely used markers in melanocytic tumors-S-100 protein, HMB-45, and Melan-A-in LM. A series of 40 cases were analyzed: 10 activations, 4 lentigines, 7 nevi, 12 in situ melanomas, and 7 invasive melanomas. The sensitivity of S-100 protein is weak in benign and malignant intraepithelial melanocytes of the nail matrix, and if this marker is performed alone, it may be wrongly reassuring. However, the use of S-100 protein is essential to differentiate invasive melanoma, lacking an intraepithelial component, and particularly desmoplastic melanoma, from epithelial and mesenchymal tumors. HMB-45 and Melan-A are more sensitive than S-100 protein for the evaluation of intraepithelial melanocytic proliferation of the nail apparatus, with HMB-45 being the most intense marker. In the dermal component, HMB-45 and Melan-A were less sensitive than S-100 protein. In conclusion, we recommend that the panel of antibodies used for histological evaluation of LM should include HMB-45 and/or Melan-A and S-100 protein only if an invasive melanoma is suspected.

Mees' Lines

There are different nail manifestations of systemic diseases. This case represents Mees' lines. In the current report, this phenomenon was caused by chemotherapy agents used for treatment of leukemia. It was caused by medication insult to the nail matrix. Nonblanching and impalpable nail bands, migration with the nail growth, and thumb involvement differentiate Mees' from Beau's and Muehrcke's lines.

Proximal nail fold-lunula double punch technique: A less invasive method for sampling nail matrix without nail avulsion

Proximal nail fold-lunula double punch technique: A less invasive method for sampling nail matrix without nail avulsion

Nail Matrix Phenolization for Treatment of Ingrowing Nail: Technique Report and Recurrence Rate of 267 Surgeries

Nail Matrix Phenolization for Treatment of Ingrowing Nail: Technique Report and Recurrence Rate of 267 Surgeries

Partial nail avulsion: habit or evidence based?

Onychocryptosis is a relatively common condition that can cause significant pain and discomfort. Partial nail avulsion (PNA) with phenolisation is a straightforward procedure performed by podiatrists on a daily basis. The procedure has shown a high rate of efficacy and low recurrence rate, and can be performed on high risk patients with close post-operative monitoring and those with concomitant infection. PNA with phenolisation of the nail matrix is a non-invasive procedure that does not require the use of an operating theatre and can be carried out in the podiatrist’s rooms. Pre-operative measures do need to be taken, a local sterile field should be set up and the toe and forefoot should be scrubbed. Once the procedure has been completed healing can be expected in 4-8 weeks. The PNA procedure has been taught to undergraduate podiatrists since the late 1970’s and has developed many small variations in how the procedure is carried out. Variations vary from pre-operative management (type of antisepsis used), phenolisation time (reported to be between 1 to 5 minutes), type of post phenol irrigation (saline, isopropyl alcohol or no irrigation) and post-operative dressing regimen. These variations however are usually operator dependant and based on personal experience. Post-operative management of PNA wounds have attracted a lot of interest, with the use of different dressings (provodone-iodine impregnated gauze and paraffin gauze) and topical medicaments (manuka honey, intrasite gel) aimed at increasing the healing rate and reducing the rate of infection, but quantitative analysis of the colonisation of the wound bed shows a bacterial count of zero after the use of phenol. The case of the phenolised wound is an interesting one, an acute wound that heals by secondary intention and freely discharges for 2-4 weeks postoperatively. After the application phenol and the destruction of all microbiological matter the post-operative focus should be in nurturing the recolonisation of the nail bed. Wounds that have a high as well as a low bacterial count have been shown to have an effect healing rates, but no studies have investigated the microbiological behaviour of a phenolised PNA wound.

Outbreak of Nail Matrix Arrest Following Hand-Foot-Mouth Disease

Outbreak of Nail Matrix Arrest Following Hand-Foot-Mouth Disease

Phenol application to distal nail matrix for the treatment of nail thickening

Phenol application to distal nail matrix for the treatment of nail thickening

Correction of Pincer Nail Deformity Using Dermal Grafting

Pincer nail deformity is characterized by excessive curvature and distortion of the nail in the transverse dimension, and particularly at the distal part of the nail plate. This deformity leads to pinching off and loss of soft tissue in the affected digit, causing severe pain. Many treatment methods have been proposed; however, an effective long-term method preserving the nail matrix has not yet been established. We present here a case of pincer nail in the left thumb in a 49-year-old woman who was treated successfully with dermal grafting under the nail bed. We describe the surgical method and the treatment results. To the best of our knowledge, this is the first report in the Korean medical literature on the use of dermal grafting for the treatment of pincer nail deformity.

Nail psoriasis: a retrospective study on the effectiveness of systemic treatments (classical and biological therapy)

Nail psoriasis represents a challenge for specialists. There is no comparative study of systemic treatment's effectiveness at this site. Evaluate the response of nail psoriasis to classical and biological therapy and to compare the effectiveness and safety of the different treatments. We performed a retrospective study of 84 patients with moderate-severe psoriasis seen at our Department between January 2006 and January 2009. Psoriasis was severe in 53.4%. In 75% of cases, the fingernails were affected, and the mixed form was the most frequently subtype. The mean baseline scores on the PASI and the NAPSI were 23.12 and 14.7 respectively; the correlation between the two scores fell at weeks 12 and 24 but had risen again at week 48. The baseline NAPSI score tended to be lower in women and significantly higher in patients over 65 years of age, family history of psoriasis, severe psoriasis and nail matrix involvement. In our series, 58.3% received classical treatment (acitretin, methotrexate, cyclosporin, PUVA, NUVB, REPUVA, RENUVB) and 41.7% received biological treatment (infliximab, efalizumab, etanercept, adalimumab).Significant reductions were found (P < 0.05) in the mean NAPSI scores at 12, 24 and 48 weeks with all the antipsoriatic agents except NUVB; significantly greater with cyclosporine (P < 0.01) and biological as infliximab and adalimumab at 12 and 24 weeks (differences between treatments disappeared at 48 weeks). The response to treatment is slower in the nail lesions than in the skin lesions. The improvement of nail psoriasis is significant both with the classical treatments significantly higher in cyclosporin; and biological treatment (infliximab and adalimumab at 12 and 24 weeks).

Evaluation of the efficacy of methotrexate and cyclosporine therapies on psoriatic nails: a one‐blind, randomized study

Treatment of psoriatic nail is difficult. The aim of this study was to evaluate and compare the efficacy and safety of methotrexate and cyclosporine in psoriatic nail. Thirty-seven psoriatic patients with nail involvement were randomized to treatment with methotrexate (initial dose, 15 mg per week) or cyclosporine (initial dose, 5 mg per kg of bodyweight per day) for 24 weeks. The primary outcome was the Nail Psoriasis Severity Index (NAPSI). The Psoriasis Area and Severity Index (PASI), doctor and patient global score were also measured. The scores were determined by a blinded observer. Seventeen patients completed the study in each group. The mean percentages of reduction of the NAPSI score after methotrexate and cyclosporine treatments were 43.3% and 37.2%, respectively. No significant differences between the treatment groups was found for in the NAPSI, PASI, physician's and patient's global score at the end of the study period. The methotrexate group showed a significant improvement in nail matrix scores and the cyclosporine group in nail bed score. Moderate effectiveness on psoriatic nail was found in the two treatment agents and there were no significant differences in efficacy between the groups. A significant improvement was detected in methotrexate group for the nail matrix findings, and in cyclosporine group for the nail bed findings.

Subtilisin-γ-Glutamyl Transpeptidase: A Novel Combination as Ungual Enhancer for Prospective Topical Application

A feather degrading strain of Bacillus licheniformis ER-15 was isolated which also degraded α-keratin of hooves. A detailed analysis revealed that a novel monomeric γ-glutamyl transpeptidase (GGT(30)), a proteolytic product of heterodimeric 67 kDa γ-glutamyl transpeptidase (GGT(67)), assists subtilisin during its action on α keratin. An equimolar combination of subtilisin and GGT(30) was designated as KerN and was used as ungual enhancer for topical application. KerN was effective in releasing proteins from nail plate surface and 300 µg of enzyme could release 41 µg protein/mg of nail after 24 h treatment. Scanning electron micrograph (SEM) revealed loosening of nail matrix confirming the action of KerN on nail keratin. Drug permeation studies revealed permeation of clotrimazole through both enzymatically pretreated nail plates and also through nail plates in presence of KerN. Nearly 58% drug could be retained by nail plates after 24 h of 300 µg/mL KerN which further enhanced up to 97% by prolonging the enzyme application. The enzyme was found to be stable in presence of drug even after 72 h. Thus, KerN can be used as an additive in formulation of topical drug for onchomycosis.

A New Surgical Technique for the Correction of Pincer-Nail Deformity: Combination of Splint and Nail Bed Cutting

Pincer nail is a kind of nail deformity characterized by a transverse overcurvature of the nail that increases along the longitudinal axis. Many conservative and surgical treatment modalities have been reported. Widening the nail bed and use of aspiration tube splint in pincer nail surgery. Pincer nail was treated by surgery with splinting in 11 patients. In this procedure, the nail bed is enlarged in a transverse direction using incisions on the nail bed. RESULTS The postoperative follow-up ranged from 12 to 19 months (mean 15 months). Excellent results were obtained in all patients. No further complications were reported. The splint can prevent contracture of the nail matrix and nail bed. Widening and flattening the nail bed using an aspiration tube splint provided a longstanding effective treatment of pincer nail deformity and pain relief. The authors have indicated no significant interest with commercial supporters.

Relationship between the deletion of GSTM1, GSTT1 genes and susceptibility to malignant of nail matrix naevus

Objective To study the relationship between the deletion of glutathione S transferase M1 ( GSTM1), glutathione S transferase T1 ( GSTT1 ) and susceptibility to Malignant of nail matrix naevus and its mechanism. Methods Using the method of PCR to detect the genotypes of GSTM1 and GSTT1 in 77 Malignant of nail matrix naevus patients and 107 nail matrix naevns people. Results There were 58.4% (45/77) malignant patients with GSTM1 null genotype in all cases and 42. 1% (45/107) persons with GSTM1 null genotype in the nail matrix naevus people, and there was significant difference between the two groups (x2 = 4. 811, P ＜ 0. 05 ), and its OR was 1. 938 (95% CI 1. 095-3. 581 ); There were 57. 1% (44/77) malignant patients with GSTT1 null genotype in all cases and 50. 5% (54/107) persons with GSTT1 null genotype in the nail matrix naevus people, and there wasnt significant difference between the two groups (x2 = 0. 802, P ＞ 0. 05 ) ;There were 26 cases with GSTM1 null/GSTT1 null genotype in malignant patients which was significantly higher than those in the nail matrix naevus people, and its OR was2.451 (95%CI 1.067-5.633). Conclusion GSTM1 null genotype and GSTM1/GSTT1 combined null genotype laid in much more malignant of nail matrix naevus patients than nail matrix naevus people,and it could highly increase the risk of malignant of nail matrix naevus occurrence. Key words: Nail matrix naevus; Glutathione S transferase M1; Glutathione S transferase T1

Standing nail deformity of the great toes with multiple brachymetacarpia and brachyphalangia of the hand

We report the surgical treatment of two patients who had rare complex anomalies of the foot and hand. The nails of their great toes curved dorsally as if they were standing on the nail matrix. They had difficulty in flexing the interphalangeal joint of the great toe. Their hands showed multiple and sporadic brachymetacarpia and brachyphalangia.

Une nouvelle cause de périonyxis chronique : la rétronychie

Retronychia is the phenomenon of ingrown nail resulting in inflammation of the proximal subungual fold and is a newly described entity. Herein, we report a new case revealed through chronic proximal perionyxis. A 52-year-old woman followed up for hypothyroidism, for which she was receiving treatment, consulted for pain in the lateral fold of the left big toe that had been ongoing for four months and for which glomic tumour was the suspected cause. Questioning revealed repeated microtrauma due to wearing of tight shoes and lack of growth of the toenail over the previous four months (in contrast with the contralateral toenail). Examination showed painful proximal perionyxis of the left big toe, with discharge from the subungual fold. Ultrasound examination of the subungual fold revealed effusion of fluid around the matrix, and this was confirmed by MRI. Surgical avulsion of the nail was carried out, and recovery was complete. Retronychia is the result of a loss of continuity between the nail plate and the nail matrix, generally as a result of mechanical factors (distal trauma). However, unlike onychomadesis or Beau's lines, there is a disturbance of alignment between the two parts of the nail, which is normally maintained by the proximal subungual fold. This prevents newly formed nail from progressing towards the distal part of the plate, which itself is pushed into the nail bed and forced towards the proximal fold, causing inflammation of the latter structure. In our case, the pain recorded in the lateral fold was misleading, hence the ultimately unnecessary use of MRI to rule out the hypothesis of glomic tumour. Paronychia, discontinuation of nail growth and weeping through the subungual fold all argued in favour of a diagnosis of retronychia, which was confirmed by surgery. Surgical nail removal is the curative treatment for retronychia and results in complete cure without relapse or occurrence. Retronychia should be suspected in the event of persistent proximal perionyxis, particularly in a setting of trauma with interrupted nail growth. Nail avulsion constitutes both a diagnostic and a therapeutic procedure.

Ist die Hakenplatte die geeignete Osteosynthese zur Versorgung der dorsalen Endphalanxbasisfraktur (knöcherner Strecksehnenausriss) beim Sportler mit starker Belastung der Finger?

Aim of the presented investigation was to work out the short- and mid-term outcomes after operative treatment of distal phalanx fractures near to the base of type Doyle IVb and IVc (osseous pull out of the extensor tendon) by means of a hook plate in patients with extreme exposure of the hand by athletic activities. Between February 2002 and September 2009 77 patients were treated by operation in our hospital by means of a hook plate due to a traumatic fracture of the dorsal distal phalanx near to the base of type Doyle IVb and IVc (osseous pull out of the extensor tendon) by means of a hook plate (Aerni plate/S2-Prong-Plate) of Stryker Leibinger. 64 of these 77 patients incur the fracture while exercising sport. 46 of these 64 patients were clinically and radiologically followed up within a retrospective study. To assess the therapy's outcome a specific scoring scheme containing subjective and objective parameters was elaborated in order to gain a transparent result of the treatment. According to this scoring scheme 84.79 % of the patients reached a very good or good result. Nail growth defects by an intraoperative injury of nail matrix represents an essential complication of the presented surgical method. By means of the presented method in the majority of the cases good or very good results could be achieved. That method represents a simple, safe and less complicate possibility to treat the distal phalanx fractures near to the base type IVb and IVc according to Doyle and it is considered as a useful alternative to other procedures.

Transverse ridging of the nails

A 70-year-old man with hormone-refractory prostate cancer who had been treated with three cycles of docetaxel and prednisone chemotherapy presented with three evenly spaced, transverse lines on all of his nails (Fig. 1). Diagnosis of transverse ridging of the nails, also known as Beau’s lines, was made. Beau’s lines are typical signs of acute toxicity to the nail matrix keratinocytes with transient arrest in the nail plate production. The nail shows a transverse depression that migrates distally as the nail grows. These nail abnormalities are not exclusive to drugs, but are commonly seen after trauma or systemic illness. Drug-induced Beau’s lines are usually dose-related and reproducible with re-administration of the drug. Multiple Beau’s lines in the same nail indicate repetitive cycles of drug intake, as illustrated in this patient, and reflect repeated interruptions to the normal rate of nail growth (approximately 0.1 mm per day). There are no preventive measures or treatments, and the changes generally resolve as the nails grow out.

Revised UK guidelines for the management of cutaneous melanoma 2010

These guidelines for the management of cutaneous melanoma present an evidence-based guidance for treatment, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of epidemiology, diagnosis, investigation, and follow-up.