Late-Onset Hydroxyurea-Induced Melanonychia and Tongue Hyperpigmentation in a Patient With Polycythemia Vera: A Case Report

In a rare case, a 70-year-old female with polycythemia vera developed late-onset melanonychia, a seldom-documented side effect of hydroxyurea. Typically, melanonychia emerges within months of treatment, but this case is unique as it occurred four years into therapy. Notably, the patient, with darker skin, also had hyperpigmentation of her hands and tongue. Her history of hydroxyurea-associated ulcers and symptoms worsening with dose adjustment suggested drug involvement. While mucocutaneous hyperpigmentation from hydroxyurea is known, melanonychia and tongue hyperpigmentation are rarely reported, mostly in early treatment. This case highlights the importance of recognizing these side effects, especially in diverse populations and darker skin tones. The diverse skin tones seen in Sub-Saharan Africa add complexity to diagnosing such dermatological conditions, highlighting the need for awareness. Melanonychia can mimic severe conditions such as subungual melanoma, emphasizing the significance of accurate recognition and management without invasive tests. Educating clinicians and patients about these benign drug-related phenomena is essential for precise identification and management. This case contributes to understanding late-onset hydroxyurea-induced melanonychia and tongue hyperpigmentation, enhancing clinical knowledge in diverse populations.

Melanoma in skin of color: Part I. Epidemiology and clinical presentation

Although there is a higher incidence of melanoma among non-Hispanic White individuals, melanoma is diagnosed at more advanced stages and associated with worse survival rates among individuals with skin of color (SOC). The proportions of melanoma subtypes differ across racial groups, with acral lentiginous melanoma and mucosal melanoma representing higher proportions of melanoma diagnoses in individuals with SOC compared to White individuals. The recognition of distinct differences in anatomic locations and dermatoscopic patterns may facilitate the appropriate differentiation of physiologic from pathologic pigmentation. The first article of this continuing medical education series will focus on the epidemiology and clinical presentation of melanoma in individuals with SOC, with the aim of improving early diagnoses and clinical outcomes.

Clinical and dermoscopic features of nail unit melanoma in an Australian nail clinic cohort

Nail unit melanoma carries diagnostic challenges conferring with its poor prognosis. This audit aims to characterise both clinical and dermoscopic features of nail unit malignant lesions and compare them with biopsied benign lesions. It focuses on informing future practice by aiding in the stratification and recognition of malignant diagnostic patterns in the Australian context.

Incipient Melanonychia: Benign Finding or Occult Malignancy? A Case Report of Subungual Melanoma

Subungual melanomas are rare neoplasms that tend to debut as longitudinal melanonychia. They are primarily found in patients over 60 years of age and are usually diagnosed late, representing a diagnostic challenge. We present a case report of a 59-year-old female Hispanic patient who initially presented with melanonychia and was eventually diagnosed with subungual melanoma in situ. She was surgically treated and, after three months, remained healthy. Relevant risk factors, clinical and onychoscopic findings, diagnostic criteria, and treatment options are also discussed. Since many benign entities present similarly, high clinical suspicion is critical for diagnosing this entity.

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

Melanocytic lesions in the nail apparatus are often challenging. Both subungual melanomas (SUM) and blue naevus of the nail are very rare. Occasionally, melanomas may mimic blue naevus histologically. Benign and malignant blue melanocytic lesions are commonly associated with G protein mutations, a distinct abnormality not associated with conventional subungual melanomas. We describe the clinical, histological and immunohistochemical features of nine cases of SUM with blue naevus-like morphological features. Mutations in exon 4 and 5 of GNAQ and GNA11 were investigated in two cases, which showed no mutations. RNA-seq of one case revealed unknown mutations along with mutations in ATM, METK and ARID1A. Our study delineates a variant of SUM that mimics blue naevus. Awareness of this pitfall is important when evaluating heavily pigmented lesions around the nail in order to avoid misdiagnosis. Appropriate sampling of subungual lesions and clinicopathological correlation are paramount to reach the correct diagnosis.

A Traditional Chinese Herb Citri Reticulatae Pericarpium Induced Melanonychia

The common causes for melanonychia include melanoma, repetitive trauma, underlying systemic diseases, onychomycosis, pseudomonas infection and drugs. Drug-induced melanonychia usually affects numerous nails and appears as light brown to black pigmentation on the deck or nail bed with longitudinal, transverse or diffuse distribution. In previous cases, a number of chemotherapeutic agents such as azathioprine, bleomycin sulfate, cyclophosphamide, hydroxyurea and methotrexate were usually linked to melanonychia. Citri reticulatae pericarpium (CRP) is a traditional Chinese herb which is widely used in many foods and health care products in China. Up till now, there were no adverse reactions of CRP reported throughout the literature. Herein, we firstly reported a case of melanonychia in a 67-year-old man caused by CRP for external use.

Nail discoloration in pediatric skin of color patients

Nail pigmentation in children can cause significant anxiety in parents and clinicians. Different pigments of the nails, such as yellow, orange, and green, can all occur; however, this paper will focus on the dark pigments: brown, gray, and black pigmentation of the nails. Many causes of dark coloration of the nails exist; almost all causes in pediatric patients are benign and require no treatment. Melanoma is the one diagnosis that physicians do not want to miss. Fortunately, this is extremely rare in children.

Distribution of cellular remnants of melanocytes in the nail plate: Clue to the diagnosis of subungual melanoma

BACKGROUND

Previous studies reported that cellular remnants in the nail plate could be a diagnostic clue for subungual melanoma (SUM). We sought to characterize the histopathologic features of cellular remnants in the nail plates of SUM patients.

METHODS

A retrospective case-control study was conducted in a single tertiary center from 2012 to 2019. Twenty-three patients with pathologically diagnosed SUM and eight nail matrix nevi (NMN) patients were recruited. The analysis of the nail plate specimens focused on large cellular remnants of melanocytes (LCRMs). Longitudinal linear density and vertical distribution pattern of the LCRMs were scrutinized for possible features distinguishing SUM from NMN.

RESULTS

The median linear density of the LCRMs was significantly higher in the SUM samples than in the NMN samples. LCRMs in the SUM samples were more dorsally distributed than those in the NMN samples. In invasive SUM, LCRMs were more likely to be found in the dorsal part of the nail plate compared to SUM in situ.

CONCLUSION

Nail plate specimens should not be overlooked in the histopathological examination of melanonychia. High-density LCRMs with more dispersion to the dorsal side might be suggestive of SUM.

Clinical and onychoscopic features of histopathologically proven onychopapillomas and literature update

BACKGROUND

Onychopapilloma is a benign tumor of the distal nail matrix and proximal nail bed with heterogeneous clinical presentations. It poses a diagnostic challenge because it could mimic subungual malignancies and inflammatory conditions. Clinical, onychoscopic, and histopathological clues play critical roles in diagnosis.

METHODS

We performed a retrospective chart review of onychopapilloma cases collected over 10 years, and characterized the clinical, onychoscopic, and histopathological features of onychopapilloma at an academic institution.

RESULTS

We obtained 17 biopsy-confirmed cases of onychopapilloma. Among our cases, we found manifestation of onychopapilloma as longitudinal erythronychia, longitudinal leukonychia, yellow-brown chromonychia, and longitudinal melanonychia. Long longitudinal or short splinter hemorrhages may be present. Distal fissuring with V-shaped notch, subungual keratotic mass, and onycholysis are other discernable features. Histopathological features include papillomatosis, epidermal hyperplasia, acanthosis of the distal nail bed, premature keratinization, matrix metaplasia, hyperkeratosis, and splinter hemorrhages; histopathological signs of malignancy were not observed in any of our cases.

CONCLUSIONS

Onychopapilloma has polymorphic clinical and morphological features. Onychoscopic and histopathological studies are important to help exclude malignant mimickers. Consider onychopapilloma in the differential diagnoses of a monodactylous longitudinal streak in the nail, especially on the left thumb of an adult female.

The value of dermoscopy of the nail plate free edge and hyponychium

The non-invasive examination of the nail unit using a dermoscope is known as onychoscopy. This technique has become increasingly appreciated to facilitate the clinical diagnosis of nail disorders, opening up a valuable second front with a potential to avoid invasive diagnostic procedures. During a nail consultation, the nail unit should always be examined with the aid of a dermatoscope in all its components. The aim of this paper is to provide practical information about onychoscopy of the nail plate free edge and hyponychium, two components of the nail unit difficult to evaluate at naked eye and often forgotten, but of paramount importance.

Fungal Melanonychia as a Solitary Black Linear Vertical Nail Plate Streak: Case Report and Literature Review of Candida-Associated Longitudinal Melanonychia Striata

Longitudinal melanonychia striata, presenting as a black linear vertical band of the nail plate, can be caused by pigmented lesions and non-pigmented etiologies. A fungal infection of the nail plate, also referred to as onychomycosis or tinea unguim, can result from dermatophytes, non-dermatophyte molds, and Candida. Albeit rare, Candida-associated fungal melanonychia can present as a longitudinal black nail plate streak. The case of a 79-year-old man who developed a solitary linear black streak on his right fourth fingernail after a prior history of recent trauma to the digit’s nail folds is described; the fungal culture grew Candida parapsilosis. Including our patient, Candida-associated longitudinal melanonychia striata has been described in four women and two men ranging in age from 40 to 79 years (median, 70 years) at diagnosis. The black streak, present from one month to one year (median, seven months), affected either a hand digit (five patients) or the great toe (one patient). Fungal organisms were visualized on either a potassium hydroxide preparation (one patient), pathologic evaluation of a nail plate specimen (three patients), or both (one patient). Culture grew Candida parapsilosis (two patients), Candidaspecies (two patients), Candida albicans (one patient), and Candida tropicalis (one patient). All of the patients experienced clinical improvement after treatment. Topical treatment (5% amorolfine hydrochloride nail lacquer for two patients or modified Castellani paint and 1% clotrimazole cream for one man) or oral itraconazole (either as monotherapy for two women or combined with 5% amorolfine hydrochloride nail lacquer for one woman) was successfully used. Although the clinical presentation of fungal melanonychia can mimic subungual melanoma when it appears as a solitary black linear vertical nail plate streak, investigative studies--such as a potassium hydroxide preparation, nail plate pathology, nail matrix biopsy, and/or fungal culture--can be used to establish the diagnosis of Candida-associated longitudinal melanonychia striata and exclude the diagnosis of a pigmented melanocytic tumor.

Dermoscopic findings of fungal melanonychia

Introduction

There are very few studies about dermoscopic findings of fungal melanonychia (FM) apart from the case reports.

Aim

To reveal and identify dermoscopic findings which facilitate diagnosis of the FM.

Material and methods

The study included a total of 42 nails from 33 patients diagnosed with FM on the basis of the clinical history, physical examination, dermoscopic findings and microbiological investigation. All of the dermoscopic images were retrospectively reviewed and the findings identified were recorded in a period of 1 year.

Results

The most common presentation was homogenous brown pigmentation (n = 15, 35.7%). The other presentations included: homogenous black (n = 9, 21.4%), homogenous grey (n = 9, 21.4%), clumped/granular black (n = 7, 16.6%) and irregular longitudinal black (n = 4, 9.5%) pigmentation. Superficial transverse striation was observed in 11 (26.1%) nails. Twenty (47.6%) nails showed white streaks (white longitudinal striae) and 6 (14.2%) nails showed distal white jagged edge (also known as "spikes"). Twenty-two (52.3%) nails had at least one of white streaks and jagged edge findings. 4 (9.5%) nails showed pseudo Hutchinson's sign.

Conclusions

To the best of our knowledge, this is the most comprehensive study regarding the dermoscopic patterns of FM. Here, we also evaluated onychomycosis associated dermoscopic findings like white longitudinal striae and jagged edges. Our study, along with the previous studies, showed that dermoscopy can be a very helpful method in the diagnosis of FM. Long disease duration, homogenous pigmentation pattern, presence of white streaks and jagged edges are the main clues to FM.

Intra-Operative Dermoscopy in Assessment of Melanonychia and as a Guide for Biopsy

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.

Melanonychia - Clues for a Correct Diagnosis

Melanonychia represents a brown to black discoloration of the nail plate that may be induced by benign or malignant causes. Two main mechanisms are involved in the appearance of melanonychias, i.e., melanocytic activation and melanocytic hyperplasia. The distinction between the two can be made based on the medical history of the patient, the clinical picture, dermoscopy, and histopathological examination and is essential for the adequate management of the patient. We review the main causes of melanonychia, with emphasis on the clues to the diagnosis of subungual melanoma.

Melanonychia: Etiology, Diagnosis, and Treatment

Melanonychia is a very worrisome entity for most patients. It is characterized by brownish black discoloration of nail plate and is a common cause of nail plate pigmentation. The aetiology of melanonychia ranges from more common benign causes to less common invasive and in situ melanomas. Melanonychia especially in a longitudinal band form can be due to both local and systemic causes. An understanding of the epidemiology, pathophysiology and clinical details is necessary for adequate patient care and counseling. It not only helps in the early recognition of melanoma but also prevents unnecessary invasive work up in cases with benign etiology. An early diagnosis of malignant lesion is the key to favourable outcome. Though there are no established guidelines or algorithms for evaluating melanonychia, a systematic stepwise approach has been suggested to arrive at a probable etiology. We, hereby, review the aetiology, clinical features, diagnostic modalities and management protocol for melanonychia.

The Importance of Dermatoscopy for the Diagnosis of Melanonychia

Melanonychia is the brown or black color of the finger or toe nail due to melanin deposition or melanocytes in the nail plate. The evidence of melanocytic disease is made by the dermatoscope, which allows to highlight the anomalies of the plate. The purpose of our study was to evaluate dermatoscopically the melanonychia, both in the form of stain and longitudinal on finger and/or toe nails in order to establish the type of nail hyperpigmentation.

MATERIALS AND METHOD

33 patients with longitudinal and stain melanonychia were examined with 30x Molemax HD computerized dermatoscope between May 2017-septembre 2018 in this prospective study conducted in the Department of Dermatology of Medical Center Dr. Ianosi (Craiova, Romania). Clinical data included: type of melanonychia, number and name of involved fingers, the presence or absence of fungal infections, nail apparatus tumors or hemorrhage.

RESULTS

The most frequent nail diagnosis was fungal infection (onychomycosis) observed in 18 patients (54.54%), malignant melanoma was diagnosed in 1 patient (3.03%) and the junctional nevus in 4 patients (12.12%). In 18 patients which has longitudinal melanonychia, the most frequent involved finger was the big toe, and in 15 patients which has stain melanonychia, all of them (100%) had affected the big toe, 7 (46.66%) patients had affected the thumb and the same percent the forth finger.

CONCLUSION

Nail dermatoscopy is an important method in establishing the diagnosis of melanonychia and allowed to avoid unnecessary biopsy for melanonychia.

Spectrum of cutaneous lupus erythematosus in South Africans with systemic lupus erythematosus

BACKGROUND

Cutaneous involvement is very common in systemic lupus erythematosus. We describe the prevalence and spectrum of lupus-specific (cutaneous lupus erythematosus) and non-specific cutaneous features amongst mostly black South Africans with systemic lupus erythematosus.

PATIENTS AND METHODS

A retrospective record review of 298 South Africans (262 blacks and 36 non-blacks) with systemic lupus erythematosus was carried out. Cutaneous features were classified according to the Gilliam and Sontheimer classification of cutaneous lupus.

RESULTS

Most (81.5%) patients were black African females. The mean (SD) age at diagnosis and follow-up duration were 35.0 (11.8) and 8.0 (5.9) years, respectively. Cutaneous lupus erythematosus was seen in 76.1% of patients, mainly chronic cutaneous lupus erythematosus with the discoid lupus erythematosus subtype seen in 52.1% of patients. Acute cutaneous lupus erythematosus was seen in 30.2% of patients and was more common in non-blacks than blacks (odds ratio = 3.8 (1.9-7.9)); localized acute cutaneous lupus erythematosus was more common than generalized acute cutaneous lupus erythematosus (odds ratio = 2.6 (1.6-4.4)). Non-specific cutaneous features occurred in 77.2%, with oral/nasal ulcers and Raynaud's phenomenon each occurring in approximately 40% of patients. Diffuse melanonychia at initial diagnosis was present in 37.4% of patients and was more common in blacks than non-blacks (odds ratio = 3.1 (1.3-7.3)). Acute cutaneous lupus erythematosus was associated with renal disease (odds ratio = 2.8 (1.6-4.7)) and chronic cutaneous lupus erythematosus with arthritis (odds ratio = 2.02 (1.24-3.29)). Diffuse melanonychia was associated with less renal disease and anti-dsDNA antibody positivity (odds ratio = 0.4 (0.3-0.7) and 0.4 (0.2-0.6), respectively) and significantly lower lupus severity index scores (mean (SD) = 5.99 (1.11) vs 6.56 (1.36) in patients with no melanonychia, p < 0.05)).

CONCLUSION

In this study of South Africans with systemic lupus erythematosus, the skin was the most commonly affected organ. In general, cutaneous lupus erythematosus was associated with less severe systemic disease. Acute cutaneous lupus erythematosus was less common in blacks, whereas discoid lupus erythematosus was more common than reported in Caucasians. Diffuse melanonychia was a distinctive finding and was associated with milder systemic disease.

Use of Nail Dermoscopy in the Management of Melanonychia: Review

The term melanonychia describes a black-brown-gray pigmentation of the nail plate that, in most cases, appears as a longitudinal band. Melanonychia can be observed at any age, affecting one digit or several digits, in both fingernails and toenails. Its causes can be difficult to differentiate clinically and depend on the number of bands and on their color, edge, and width. For this reason, especially in adults and when the pigmentation is localized in one single digit, biopsy and histopathological examination still represent the gold standard for a definitive diagnosis. Dermoscopy should be used routinely in the evaluation of a pigmented nail, as it provides important information for the management of melanonychia and can help avoid unnecessary nail biopsies. In cases of melanonychia it is important to establish whether the pigment is melanin or not and to determine whether the pigmentation of melanin is due to activation or proliferation and whether it is benign or malignant.

Onychoscopy: an observational study in 237 patients from the Kashmir Valley of North India

Background

Nail disorders comprise approximately 10% of all dermatological conditions. Because diagnosis is not always possible by clinical means alone, additional diagnostic procedures may be required at times. Dermoscopy of nails (onychoscopy) has shown promising results in diagnosing various nail disorders and also avoids time-consuming investigations such as culture and biopsy.

Objective

To study the dermoscopic features of various nail disorders to determine the correlation between KOH examination and onychoscopic patterns in patients with the clinical suspicion of onychomycosis, and to differentiate benign pigmented lesions from malignant ones.

Methods

An open, observational and cross-sectional study of 237 patients was conducted. All patients underwent clinical examination and the affected nails were examined with a dermatoscope. The onychoscopic patterns were identified and recorded.

Results

The study included 237 patients with the following diagnoses: 81 onychomycosis, 63 psoriasis, 27 lichen planus, 30 longitudinal melanonychia, 24 connective tissue disorders, 5 onychophagia and nail tics, 3 subungual verrucae, 2 glomus tumor, 1 Darier disease, and 1 enchondroma. The most common onychoscopic findings were spiked pattern in cases of onychomycosis, dilated and tortuous capillaries in cases of psoriasis, longitudinal streaks and nail fragmentation in cases of lichen planus, and enlarged capillaries in cases of connective tissue diseases.

Limitations

The study was only observational and did not compare the results to biopsy and culture.

Conclusions

Onychoscopy may be used as an important diagnostic tool when evaluating nail disorders. It should be used to aid in the diagnosis of various nail disorders and to avoid unnecessary and time-consuming investigations.

"Dots and lines": A melanonychia striata in regression: Report of a case

A 2-year-old Caucasian boy with melanonychia striata with multiple striking pits on the nail plate of one fingernail is described. Nail disorders often pose diagnostic and therapeutic challenges for clinicians, especially melanonychia striata, because of the fear of a subungual melanoma. Only a few childhood cases of melanonychia striata have been described, and the multiple pits are even less common. Dots distributed along melanotic lines is a finding referred to as "dots and lines" and can be a sign of regression of melanonychia in childeren.