Goals and objectives 6/23/2018. Nail anatomy and nomenclature. David L. Kaplan, M.D.

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1 David L. Kaplan, M.D. Goals and objectives Become familiar with basic nail anatomy and nail physical examination Learn a systematic approach to identify source of nail changes Have a working differential for clinical presentations of nail changes Gain therapeutic options for common nail conditions Nail anatomy and nomenclature 6 components Generating Matrix Product of the matrix Nail plate Ensheathing Eponychium/cuticle Support Nail bed Anchoring Ligamentary Framing Nail folds Proximal, lateral, distal 1

2 Nail anatomy-dorsal view Cuticle is derived from the eponychium (proximal nail fold) Adheres to the nail plate then slowly detaches Hyponychium Junction of the nail plate, nail bed and the distal groove Where the nail detaches from the nail bed Nail anatomy Lunula Visible portion of the nail matrix Whitish color is due to keratinization of the epithelium Nail bed From the lunula to the onychocorneal band Onychodermal band Transition of the distal nail bed before it detaches from the plate Nail plate Final product of the nail unit Onychopathy Nail folds Swelling Erythema Color change Tenderness/pain Nail bed Color White Red Erythema Hemorrhage Blue Morphology Nail plate Morphology Longitudinal ridging Crumbling Thickened Brittle Other Rough texture Pitting Splitting Shape Color White Black Green Yellow 2

3 Nail folds Swelling Erythema Color change Tenderness/pain Swelling Infection Acute paronychia Chronic paronychia Connective tissue disease Scleroderma Lupus erythematosus Dermatomyositis Retronychia Nail fold swelling Paronychia Acute paronychia In patients with acute paronychia, only one nail is typically involved. The condition is characterized by rapid onset of erythema, edema, and discomfort or tenderness of the proximal and lateral nail folds, usually two to five days after the trauma. Nail fold swelling Acute paronychia The most common causative pathogen is Staphylococcus aureus, although Streptococcus pyogenes, Pseudomonas pyocyanea, and Proteus vulgaris can also cause paronychia Treatment Staphylococcal Doxycycline Trimethoprim/sulfamethoxa zole Streptococcal Cephalexin Clindamycin Mupirocin 3

4 Nail fold swelling Paronychia Psoriasis and reactive arthritis syndrome may also involve the proximal nail fold and can mimic acute paronychia Recurrent acute paronychia should raise suspicion for herpetic whitlow, which typically occurs in health care professionals as a result of topical inoculation. Clinical challenge This 45 year old housecleaner presented with a two day history of tender swollen finger after chewing off a hangnail. She cleans a house with 13 toilets. She is otherwise healthy. 4

5 Pending culture results which of the following would you choose? Keflex/Cephalexin Levaquin/levofloxacin Bactrim DS/tmp-smz Augmentin/Amoxicillin Clavulanate Rifampin Diflucan/fluconazole Lamisil/terbinafine Valtrex/Famvir Rocephin The culture grew out MRSA E. coli Klebsiella She had been started on Bactrim DS and rifampin. She resolved uneventfully. Nail fold swelling Chronic paronychia Chronic paronychia Chronic paronychia can be the result of numerous conditions, such as dish washing, finger sucking, trimming the cuticles, and frequent contact with chemicals (e.g., mild alkalis, acids). In chronic paronychia, the cuticle separates from the nail plate, leaving the region between the proximal nail fold and the nail plate vulnerable to infection by bacterial and fungal pathogens 5

6 Chronic paronychia Although Candida is often isolated in patients with chronic paronychia, this condition is not a type of onychomycosis, but rather a variety of hand dermatitis caused by environmental exposure. In many cases, Candida disappears when the physiologic barrier is restored Chronic paronychia Topical steroids versus systemic antifungals in the treatment of chronic paronychia: an open, randomized double-blind and double dummy study J Am Acad Dermatol Jul;47(1):73-6. The purpose of this study was to compare the efficacy of systemic antifungals (itraconazole or terbinafine) with a topical corticosteroid (methylprednisol one aceponate) in the treatment of patients with chronic paronychia. Of 48 nails treated with methylprednisolone aceponate, 41 were improved or cured at the end of the follow-up period. The statistical analysis showed a significant difference between the number of nails improved or cured by methylprednisolone aceponate and that of nails improved or cured with terbinafine (30 out of 57) or itraconazole (29 out of 64). Presence of Candida was not strictly linked to disease activity, and Candida eradication was associated with clinical cure in only 2 of the 18 patients who carried Candida at the beginning of the study. CONCLUSION:This study shows that topical steroids are more effective than systemic antifungals in the treatment of chronic paronychia, and supports the view that chronic paronychia is not a type of onychomycosis but a variety of hand dermatitis caused by environmental exposure. Clinical challenge This 16 year old female presented for evaluation of a few month history of a single tender fingernail. She was given cephalexin and TMP-SMX without improvement. She had been recommended to ID who suggested placement of PIC line for long term antibiotic treatment. She is otherwise healthy with no history of trauma. 6

7 At this point she was started on fluconazole orally for one week then once a week for the next three months. Three months later 7

8 Differential diagnoses Staphylococcal infection (MRSA) Gram negative bacterial infection Dermatophyte infection Candida infection Factitial baseline After 3 months of treatment Treatment Topical Loprox gel Exelderm solution Clotrimazole solution Oral Ketoconazle Fluconazole Itraconazole Treatment In a double blind placebo controlled study of chronic paronychia, topical steroids were shown to be vastly superior to either Lamisil or Sporanox orally. Topical steroids versus systemic antifungals in the treatment of chronic paronychia: an open, randomized double-blind and double dummy study. JAAD (1):73-6 8

9 Nail fold color change Telangiectasia Abnormal nail fold capillaries Nail fold capillary changes Nail fold capillaroscopy changes are based on morphology. early changes (some enlarged capillaries and some hemorrhages) active disease (frequently enlarged capillaries and frequent hemorrhages late changes (irregular enlargement, severe loss of capillaries and avascular areas. Capillaries can be called dilated if they are more than three times wider than surrounding hairpinshaped capillaries. Dermoscopic observation of the nail fold capillaries is usually made on the fourth or the third finger, avoiding the thumb, whose skin has a lower transparency. Nail fold capillary changes Nail fold findings to be evaluated include enlarged capillary loops, loss of capillaries (moderate or extensive), disorganization of normal distribution, budding (bushy) capillaries, twisted (tortuous, crossing, ramified) capillaries and capillary hemorrhages (>2 punctate hemorrhages in a finger). Ohtsuka reported this pattern in 76.4% patients with systemic sclerosis; 63.6% patients with dermatomyositis and 50% patients with mixed connective tissue disease. J Dermatol 2012;39:

10 Nail plate pathology Nail plate Morphology Longitudinal ridging Crumbling Thickened Brittle Other Rough texture Pitting Splitting Shape Color White Black Green Yellow Color White/leukonychia Black Melanonychia External Green Chromonychia Pseudomonas Yellow Yellow nail syndrome External Smoking Nail polish Nail plate pathology Nail plate Morphology Longitudinal ridging Crumbling Thickened Brittle Other Rough texture Pitting Splitting Shape Color White Black Green Yellow Longitudinal ridging age Crumbling Psoriasis Fungal infection Thickened Fungal infection Brittle Nutritional Other Rough texture Lichen planus Pitting Psoriasis Alopecia areata Splitting/onychoschizia Trauma Shape Spoon Clubbing Size Nail patella syndrome Nail plate pathology Longitudinal ridging or onychorrhexis Normal aging changes 10

11 Clinical challenge This 46 year old dentist presented for evaluation of a chronic hand dermatitis of one years duration. He had standard patch testing that was negative. He was prescribed a high potency steroid cream which controls it but does not clear it. He no other rashes elsewhere. He takes no other medications. 11

12 Differential diagnoses Contact dermatitis Psoriasis Lichen planus Dermatophyte infection Atopic dermatitis Bonus question: What would you look for or ask to assist in the diagnosis? Additional history revealed that the patient had been undergoing a divorce in addition to his hand washing and trauma from his work contributing to his psoriasis. 12

13 Nail plate Psoriasis Commonly psoriasis Topical treatment Urea Corticosteroids Vitamin D3 analogues 5-Fluorouracil Cyclosporin A Tazarotene Anthralin Corticosteroids + vitamin D3 analogues Corticosteroids + retinoids Corticosteroids + tazarotene Intralesional treatment Corticosteroids MTX Phototherapy PUVA UVA/UVB Topical treatments are often the first choice, but their effectiveness is limited to nail bed psoriasis; they are not effective on nail matrix psoriasis because they do not penetrate the nail plate and proximal nail fold. Use of clobetasol propionate (0.05%) cream twice a week, for a total of 6 months. The authors reported a reduction of hyperkeratosis by 35.2% in fingernails Acta Derm Venereol. 2002; 82(2):140. In a controlled double-blind study of 58 patients for a period of 6 months, the authors demonstrated that twice a day of calcipotriol ointment had a similar efficacy as betamethasone dipropionate (0.05%) in treating subungual hyperkeratosis after 3 9 months. Br J Dermatol Oct; 139(4):655-9 Similar efficacy of tazarotene (0.1%) cream and clobetasol propionate (0.05%) cream treatment in a doubleblind study involving 46 patients for 12 weeks. Acta Derm Venereol. 2007; 87(2): Nail plate Psoriasis Systemic treatment for psoriatic nails Methotrexate 5-15 mg/week IL corticosteroids Cyclosporine 3-4 mg/kg daily Worked better when combined with calcipotriene Acitretin mg/kg daily Biologics Psoriasis patients with nail involvement appear to correlate with psoriatic arthritis Clin Rheumatol Aug;35(8): Clinical Challenge This 71 year old male presented for evaluation of painful growths on his feet of six years duration. He has tried various topical creams without improvement. 13

14 Differential diagnoses Plantar keratoderma Psoriasis Dermatophyte infection Lichen planus Atopic dermatitis Poor foot hygiene 14

15 A skin biopsy confirmed the diagnosis of psoriasis. How would you treat him?! Topical therapy 40% urea cream Potent topical corticosteroids Topical calcipitrione or calcitrol Topical tazarotene Systemic treatment Podiatrist Nail Plate Differential Dx Infection Dermatophyte Disease Psoriasis Aging Normal water content of the nail is 18% (range 10-30%) Relative humidity affects nail hardness 15

16 Nail plate Onychoschizia Household daily chores are particularly damaging. Among the acquired general causes, hypochromic anaemia and sideropaenia, arthritic deformities of the distal joints, peripheral vascular impairment and endocrinopathies are the best known. Useful therapeutic approaches are updated. They entail protection with plastic gloves worn over light cotton glove linings, the use of nail hardeners composed of two main types of products: a modified nail varnish that functions as a base coat or a hardener, such as dimethyl urea, which overcomes the objections related to formaldehyde; a systemic drug, biotin, is still useful. J Cosmet Dermatol Jul;3(3):131-7 Nail Plate Dermatophytes Onychomycosis has 5 main subtypes, as follows: Distal lateral subungual onychomycosis (DLSO) White superficial onychomycosis (WSO) Proximal subungual onychomycosis (PSO) Endonyx onychomycosis (EO) Candidal onychomycosis Nail Plate Dermatophytes Diagnosis Though estimates vary, about 10% of Americans have it, and this increases to about 20% in people over 60 and up to 50% of those over 70. The most commonly used methods are direct KOH examination, culture, and nail biopsy Sensitivity values have been reported: % for culture % for KOH % for biopsy. The diagnostic tests independently evaluated in this meta-analysis of 2858 patients show acceptable validity, performance, and efficiency, with nail clipping with PAS staining outperforming the other two tests BMC Infect Dis 2017; 17:

17 Treatment of onychomycosis Mimickers Psoriasis Lichen Planus Bacterial Infections Onychogryphosis Traumatic onychodystrophies Yellow Nail Syndrome Toenail Cellulitis Contact Dermatitis Nail-bed Tumors Onycholysis, nonspecific Pachyonychia Congenita Norwegian scabies Two systemic treatments, terbinafine and itraconazole, are approved by the US Food and Drug Administration (FDA) for onychomycosis, taken orally for three months A statistically significantly greater percentage of the terbinafine group than itraconazole group showed negative mycology (73% vs 45.8%) Patients who were clinically cured or had only minimal symptoms at the end of the study (76.2% vs 58.1% J Am Acad Dermatol May;38(5 Pt 3):S57-63 Treatment of onychomycosis Itraconazole works by inhibiting ergosterol synthesis via cytochrome P- 450 (CYP450)-dependent demethylation step. This azole antifungal agent is metabolized in the liver by cytochrome P-450 3A4 (CYP3A4), and therefore has the potential to interact with drugs metabolized through this pathway. Terbinafine, an allylamine, is fungicidal and remains at therapeutic levels in keratinized tissues, but with a short plasma half-life of 36 hours. Terbinafine has the advantage in that it does not inhibit CYP3A4 isoenzyme during its metabolism where some 50% of all commonly prescribed drugs are metabolized. cytochrome P-450 2D6 (CYP2D6) Griseofulvin acts by disrupting the fungal mitotic spindle, inhibiting cell wall synthesis Griseofulvin is poorly absorbed, unless micronized, coated with polyethylene glycol, or given with fatty meals Griseofulvin is not indicated for those with porphyria and hepatocellular failure. Patients on warfarin-type anticoagulants may need an adjustment of their anticoagulant dose. These may cause contraceptive failure especially of low dose pills. The major drug interactions noted are with phenobarbital, anticoagulants, and oral contraceptives. In adults, it is contraindicated in pregnancy and the manufacturers caution against men fathering children for 6 months after therapy. Ketoconazole and fluconazole are FDA approved for onychomycosisi Terbinafine quarterly dosing regimen Terbinafine reaches a steady state in the nail after 1 week of treatment, whereas itraconazole may require 3 12 weeks; these levels are then sustained in the nail plate for several months. After many years of experience with terbinafine, the FDA subsequently removed the LFT monitoring recommendation from the terbinafine label Medwatch 2001 A sequence of 4 groups of office patients with DSO (n = each) were treated with pulsedosed terbinafine for 7 consecutive days at intervals of 2, 3, and 4 months (250 mg/d for 7 consecutive days every 2-4 months) Thirty-nine (93%) of the 42 patients in the first 3 groups were cured (95% binomial confidence interval, 67%- 100%) with no evidence of decrease in efficacy. However, the group of patients who received the 7- day pulse treatment every 4 months experienced significantly more failures Arch Dermatol Jun;140(6):

18 Itraconazole pulse dosing 90 patients in 3 groups: standard itraconazole pulse therapy (200mg twice per day, one week each month for three pulses) long-term pulse therapy (200mg twice per day, one week each month for six pulses) low-dose and long-term pulse therapy (200mg/day, one week per month for six pulses) The complete cure rates were 32.43% for three cycles and 75% for six cycles (p < 0.001). For six cycles, despite the administration of half-dose for patients weighing no more than 55 kg, there was no statistical difference in the complete cure rate For patients weighing no more than 55 kg, long-term halfdose itraconazole pulse therapy is recommended. Mycoses Jun 12. Fluconazole pulse dosing Study comparing the safety and efficacy of onceweekly fluconazole (150, 300, and 450 mg) for up to 12 months After two weekly doses, 30% to 33% of steady-state concentrations had been achieved in healthy nails and 22% to 29% in affected nails. Steady state was achieved in 3 to 5 months. 86% to 89% of patients in the fluconazole treatment groups were judged clinical successes as defined above compared with 8% of placebo-treated patients. Clinical cure (completely healthy nail) was achieved in 28% to 36% of fluconazoletreated patients compared with 3% of placebo-treated patients Mycologic eradication rates of 47% to 62% at the end of therapy compared with 14% for placebo The clinical relapse rate among cured patients over 6 months of follow-up was low at 4% J Am Acad Dermatol Jun;38(6 Pt 2):S Onychomycosis treatment Network Meta-Analysis of Onychomycosis Treatments. Terbinafine 250 mg was significantly superior to all treatments except itraconazole 400 mg pulse therapy. Itraconazole 400 mg pulse regimen was significantly superior to all topicals except efinaconazole 10% nail solution. Itraconazole 200 mg was significantly superior to all topical treatments, while fluconazole mg, efinaconazole 10% nail solution, tavaborole 5% nail solution, ciclopirox nail lacquer 8%, terbinafine nail solution, and amorolfine 5% nail lacquer were significantly superior to placebo. Skin Appendage Disord Sep;1(2):

19 Nail plate Rough texture Diseases Lichen planus Twenty nail dystrophy Trauma Onychotillomania Trachyonychia Nail plate Trachyonychia Trachyonychia follows an insidious disease course and is most common in the pediatric population In children, all twenty nails are usually affected and trachyonychia is more commonly idiopathic Often referred to as 20 nail dystrophy Nail plate Trachyonychia The extent of inflammation in the nail matrix is thought to contribute to the wide range of severity observed in trachyonychia. Trachyonychia is a clinical diagnosis and there is no indication for a nail biopsy in these patients. Trachyonychia never causes permanent nail damage or pterygium, including cases of trachyonychia caused by lichen planus, and for this reason, there is no necessity for a nail matrix punch or longitudinal nail biopsy, which is invasive and can cause scarring Skin Appendage Disord Sep; 2(1-2):

20 Nail plate Trachyonychia In a case series, 50% of patients (n = 12) experienced resolution or considerable improvement in 6 years regardless of treatment Australas J Dermatol Aug; 47(3): A more recent study of 36 patients with 432 affected nails has found significant improvement in 98.6% of nails after 6 months of treatment with calcipotriol/betamethasone dipropionate ointment Ann Dermatol Aug; 27(4):371-5 Nail plate Pitting A pit indicates a defect in the uppermost layer of the nail plate, which arises from the proximal nail matrix. Clusters of parakeratotic cells in the stratum corneum disrupt the process of normal keratinization. As the nail plate grows outward, these parakeratotic foci are exposed to the surrounding environment and there is a gradual sloughing of these cells leaving a distinct depression within the nail plate Nail plate Pitting Common causes Psoriasis Lichen planus Alopecia areata Eczematous dermatitis Renal failure Vitiligo Normal variant 20

21 Nail plate Lamellar splitting Onychoschizia in vitro nail changes produced by several organic solvents, detergents, water, other polar materials, and both acidic and basic solutions was studied. There was a progressive increase in severity with prolonged wetting and drying over 3 weeks Layering (peeling) was seen only after repeated hydration and dehydration. Nail plate Onychoschizia Treatment 14 patient study using electron microscopy and the effects of biotin The thickness of the nails increased by 25% and the incidence of splitting decreased J Am Acad Dermatol Dec;23(6 Pt 1): Nail plate Ridges Diseases Beau s lines Trauma Tic habit injury 21

22 Nail plate Transverse ridges Beau s lines Beau lines are horizontal grooves on the nail plate and generally involve most or all of the nails. They reflect an interruption of nail bed mitosis childbirth, surgery, severe illness, pemphigus, high fever, or chemotherapy are examples Nail plate Longitudinal splitting Tic habit Median nail dystrophy Nail plate Tic habit Habit-tic deformity is also known as onychotillomania, which includes nail biting (onychophagia), nail picking, and finger sucking. The deformity is the result of repetitive nail bed trauma from the conscious or unconscious manipulation of the cuticle. The characteristic findings include a midline furrow in the nail plate, often yellow in color, running the length of the nail, with a series of transverse ridges. Treatment includes physically covering the nails with bandages or glue to prevent further trauma. In addition, behavioral therapy and SSRIs have been tried, given the obsessive-compulsive nature of the habit J Gen Intern Med Feb;30(2):264 22

23 Median nail dystrophy A nail disorder character ized by a paramedian canal or split in the nail plate of one or more nails. Small cracks or fissures extend laterally from the central canal or split to ward the nail edge, resul ting in an appearance similar to an inverted fir tree. The condition is usually symmetrical and most of ten affects the thumbs. Nail plate shape Spoon/koilonychia Koilonychia is a condition in which the nail becomes increasingly concave and therefore is often called spoon nail. It commonly occurs in association with iron deficiency anemia. Koilonychia can be a normal finding in infants, disappearing within the first few years of development. Reported also with hemochromatosis, trauma, Raynaud disease, hypothyroidism, systemic lupus erythematosus, occupational exposure to petroleum-based solvents, nailpatella syndrome Nail plate shape Clubbing Clubbing involves thickening of the nail bed's soft tissue, particularly in the proximal end. This condition usually affects all of the fingernails and rarely occurs in a single digit. Hypervascularization of the nail bed has been observed in the microanatomy on highresolution MRI and associated with clubbed appearance of the nails. J Rheumatol Mar;41(3):

24 Nail plate shape Clubbing Clubbing can be clinically diagnosed with an examination showing Schamroth sign; absence of the diamond-shaped opening that normally appears when the digits are opposed). Lovibond angle; the angle that forms between the nail plate and the soft tissue of the distal digit) is diagnostic of clubbing if it is greater than 180 degrees. Nail plate shape Clubbing Unilateral: hemiplegia, vascular disorders Bilateral: empyema, cystic fibrosis, pulmonary fibrosis, celiac sprue, bronchiectasis, cardiac disease, cirrhosis, chronic obstructive pulmonary disease, inflammatory bowel disease 1 Clinical challenge This otherwise healthy patient presents with a groove in the nail of one finger. There is no history of trauma or infection. 24

25 Differential diagnoses Wart Cyst Amelanotic melanoma Subungual exostosis psoriasis Digital mucous cyst It is suggested digital mucous cysts are associated with osteoarthritis and osteophytes in the elderly, and usually have a communicating pedicle with the joint. One cause is by the herniation of tendon sheaths or synovial linings and is associated with degenerative joint diseases and osteophytes in the elderly The other type is caused by overproduction of mucin by fibroblasts Surgical excision is a standard therapy with a high cure rate. Chromonychia: nail color changes Brown Black White Green Yellow Red Blue 25

26 Nail plate color White Leukonychia punctatum Superficial dermatophyte infection Mees lines Leukonychia punctata Also known as "true" leukonychia, this is the most common form of leukonychia, in which small white spots appear in the nail plate Histopathologic evaluation of the leukonychia punctata r evealed multiple discrete parakeratotic foci throughout the entire thickness of the nail plate, suggesting both proximal and distal matrix involvement Arch Dermatol Nov;121(11): Superficial dermatophyte infection Superficial White Onychomycosis (SWO) is characterized by opaque, friable, whitish superficial spots on the nail plate, beginning at the dorsal surface, mainly of the feet. Baran et al. demonstrated that SWO may show infection in patches or in a striate pattern and it may sometimes be combined with either distal and lateral subungual onychomycosis or proximal white subungual onychomycosis, which is a common form of nail alterations found in patients infected with HIV and therefore a contributing factor for the diagnosis J Am Acad Dermatol. 2007;57:

27 Nail color White Classic superficial white onychomycosis (SWO) is characterized by superficial nail plate involvement. Another subcategory of SWO presents a double invasion of the nail plate, either superficial or ventral difficult to determine if it is due to superficial involvement or proximal white subungual variant. The latter may be observed in children (with thin nail plates) and is often present in HIV-positive individuals. A deep and diffuse SWO, characterized by massive penetration of the nail plate by fungi, also called pseudo-swo, represents the third subcategory J Eur Acad Dermatol Venereol Sep; 18(5): Nail plate color Mees lines Mees' lines can appear after an episode of poisoning with arsenic, thallium or other heavy metals, and can also appear if the subject is suffering from renal failure. They have been observed in chemotherapy patients. Nail plate color Black Racial Radiation therapy Malnutrition Infection Medications Minocycline Antimalarials Chemotherapy Toxic Arsenic Endocrine Addison s disease Melanocytic 27

28 Melanonychia Melanonychia can occur because of melanocytic activation or because of melanocytic proliferation due to benign or malignant causes. Three steps are needed in the evaluation of melanonychia: (1) establishing whether the pigment is melanin or not (2) determining whether the development of melanonychia is due to activation or proliferation of matrix melanocytes (3) assessing whether there is proliferation in order to determine whether the disease is benign or malignant Melanonychia is pigmentation of nail plate due to melanin; however, many nonmelanin pigments may also deposit in nail and are diagnostic confounders The first step is to ensure that the pigment is melanin and not blood Melanonychia Dermoscopy is very useful for the first step. Generally, melanotic pigmentation is brown-black, and within the nail plate and the aspect is a longitudinal band, whereas exogenous pigmentation includes different substances that adhere to the nail plate and it does not usually have a longitudinal appearance. Common causes of amelanotic pigmentation are subungual hematoma, fungal melanonychia, and Pseudomonas infection. Melanonychia The next step is to assess whether melanin is a result of melanocyte activation (gray bands) or proliferation (brownblack bands) Bands caused by melanocyte activation are benign and need not be evaluated pathologically. Number of digits that are involved: if more than 1 digit is affected, the first thought should be melanocytic activation, such as in drug-induced melanonychia, which appears with a gray background of the band with thin grayish regular and parallel lines 28

29 Melanonychia Number of digits that are involved: if more than 1 digit is affected, the first thought should be melanocytic activation, such as in drug-induced melanonychia, which appears with a gray background of the band with thin grayish regular and parallel lines Benign proliferations produce regular patterned, brownblack bands with uniform color and thickness, regularly spaced and parallel placed Melanonychia Benign proliferations produce regular patterned, brownblack bands with uniform color and thickness, regularly spaced and parallel placed Another way is to examine the free edge of nail plate For pigment located in the upper portion of free edge of nail plate, the source is likely to be in the proximal matrix whereas for pigment in the lower portion, the origin is probably in the distal matrix Melanonychia When melanonychia involves only 1 digit, a proliferative process has to be considered, and this poses the diagnostic dilemma over whether it has a benign or a malignant origin The band can be very different: the color can be more or less pronounced and homogeneous; the borders can be well defined or less sharp; and its width can range from a few millimeters to the entire nail plate. The corresponding nail plate can show some changes or be completely normal. Brown-black periungual pigmentation (Hutchinson sign) may be present. Hyperpigmentation can be present on the proximal nail fold, hyponychium as well as the periungal areas 29

30 Melanonychia Other factors Age Nail matrix nevi are typically seen in childhood, and they may be congenital or acquired. Nail melanoma in children is extremely rare Dermoscopic parameters used in adults are not valid for children Pediatr Clin North Am Apr; 61(2): ½ year old Melanonychia Longitudinal pigmented band with brownish background discoloration and pigmented lines which are parallel, regular in color, width and spacing. This picture is suggestive of a nail matrix nevus Melanonychia Other factors Age Nail matrix nevi are typically seen in childhood, and they may be congenital or acquired. Nail melanoma in children is extremely rare Dermoscopic parameters used in adults are not valid for children Pediatr Clin North Am Apr; 61(2): Dermoscopic criteria for benign and malignant nail melanocyte lesions began in 2007 but it is not always reliable in the management of pigmented nail lesions An Bras Dermatol Mar- Apr; 88(2): A recent study demonstrated a strong association between clinical and dermoscopic findings in nail band pigmentation, helping to distinguish whether a band is benign or malignant. The authors identify 3 important dermoscopic patterns that could help in this distinction: (1) the width of the band, involving more than two-thirds of the nail plate in melanoma (2) the presence of a gray-toblack color (3) the presence of nail dystrophy, which increases the risk of detecting a nail melanoma 3 times. J Eur Acad Dermatol Venereol Apr; 31(4):

31 Melanonychia Dermoscopic parameters used in adults are not valid for children Pediatr Clin North Am Apr; 61(2): Dermoscopic criteria for benign and malignant nail melanocyte lesions began in 2007 but it is not always reliable in the management of pigmented nail lesions An Bras Dermatol Mar-Apr; 88(2): Melanonychia Micro-Hutchinson s Dermoscopy of the hyponychium and periungual tissues permits discovering the micro- Hutchinson sign, a periungual pigmentation seen with a dermoscope but not with the naked eye that corresponds to the initial radial growth of melanoma into adjacent tissue. Micro Hutchinson sign was defined by the visibility on dermoscopy of a pigmentation of the periungual tissues that could not be seen with the naked eye Melanonychia Pseudo-Hutchinson s sign Studies evaluating the diagnostic test characteristics of Hutchinson sign are lacking in both the adult and pediatric populations. Aside from nail unit melanoma and congenital nevi, other entities to consider in the differential diagnosis include the following: ethnic pigmentation, trauma, systemic medical illness such as hyperthyroidism and Cushing syndrome, depositional disorders, medications, and syndromes of mucocutaneous hyperpigmentation 31

32 Melanonychia More criteria A (age, Afro-Americans, native Americans and Asians): fifth and seventh decades; B (nail band): color from brown to black, 3mm wide, irregular borders; C (change): rapid increase in size of band and/or change in nail morphology; D (digit involved): thumb > hallux > index finger, dominant hand, only one digit; E (extension): Hutchinson s sign; F (family): personal or familial history of nevi dysplastic syndrome and melanoma. J Am Acad Dermatol Feb; 42(2 Pt 1): Melanonychia Even more criteria Not pathognomonic of melanoma such as non-homogeneous pigmentation with different colored lines the proximal area wider than the distal area (triangular) Triangle sign An Bras Dermatol Mar- Apr;88(2): Nail plate color Green Chloronychia Caused by Gram-negative bacteria, usually P. aeruginosa, but can also be caused by Klebsiella spp. and Gram-positive bacteria like Staphylococcus aureus More than half of all clinical isolates produce the bluegreen pigments pyoverdin and pyocyanin Chloronychia is more common in homemakers, barbers, dishwashers, bakers and medical personnel. 32

33 Nail plate color Green Treatment Cutting off the detached nail plate and treating with a 2% sodium hypochlorite solution twice daily Topical silver sulfadiazine, ciprofloxacin, and gentamicin Nail plate color yellow Yellow Infections Stains Nail polish True yellow nail syndrome Nail plate color Yellow nail Infections Candida-, Aspergillusor dermatophytecaused nail mycosis may cause such discoloration 33

34 Nail plate color Yellow nail syndrome Based on a triad associating yellow nail discoloration, pulmonary manifestations (chronic cough, bronchiectasia, pleural effusion) and lower limb lymphedema. Chronic sinusitis is frequently associated with the triad. Etiology of remains unknown Lymphatic involvement is often evoked to explain lymphedema, pleural effusion (particularly chylothorax) or nail discoloration Oral vitamin E is the only agent that successfully treated YNS. prescribed at IU/day with incomplete or inconstant efficacy Nail bed color Blue nails Blue nail is most commonly caused by drugs, including minocycline, antimalarials, cyclosphosphamide, doxorubicin and bleomycin Nail bed pathology Morphology Nail bed Color White Red Erythema Hemorrhage Blue Morphology Morphology Onycholysis Tumors Benign Malignant 34

35 Nail bed pathology Onycholysis Trauma Infections Dermatophyte Candida Pseudomonas Opportunistic Medication 5-fluorouracil Antibiotics Diseases Psoriasis Oil slick Lichen planus Neoplastic Warts Thyroid disease Clinical challenge This 19 year old female presented for evaluation of fingernail problems after taking doxycycline 100 mg twice a day for a presumed staphylococcal infection by her regular physician. She is otherwise healthy and does not have any other rashes. 35

36 Differential diagnoses Onychomycosis Candida onycholysis Photo-onycholysis Traumatic injury Psoriasis This patient had developed a photoonycholysis while taking the doxycycline. The discontinuation of therapy will result in the slow but steady improvement. 36

37 Nail bed color Terry s nails Terry s nail is defined as a mm brown to pink distal band with proximal nail bed whiteness occupying approximately 80 % of nail bed This condition is frequently associated with cirrhosis, chronic congestive heart failure, and adult-onset diabetes mellitus J Gen Intern Med 2016 Aug; 31(8): 970. Nail bed color Lindsay s nails Lindsay s nails, or half-andhalf nails, were described in 1967 as red, pink, or brown bands occupying 20 to 60% of the nail bed in patients with chronic kidney disease. In Lindsay s nail, the proximal part of the nail is white, while the distal portion occupying 20 % to 60 % of nail bed is reddishbrown and does not fade with pressure This condition can be found in up to 40 % of patients of chronic kidney disease Also referred to as half and half nails Nail bed erythema Red nail or erythronychia can involve the nail bed either longitudinally or diffusely or be limited to the lunulae. Several conditions, including Darier s disease, lichen planus, amyloidosis, warty dyskeratoma, glomus tumour, onychopapilloma, Bowen s disease, and melanoma, have been reported to cause longitudinal erythronychia 37

38 Nail bed color Red lunula Connective tissue diseases Rheumatoid arthritis Lupus erythematosus Dermatomyositis Heart failure Psoriasis Alopecia areata Lupus erythematosus Nail bed hemorrhages Splinter hemorrhages Splinter hemorrhages are redbrown, longitudinal lines occurring in the nail bed (not the nail plate) that develop secondary to leaky capillaries. Splinter hemorrhages historically have been associated with endocarditis, typically appearing in the midportion of the nail. However, only 15 percent of patients with endocarditis have them Many causes of the condition have been identified. The most common cause is trauma Nail bed color Muehrcke s nails Muehrcke lines are pairs of transverse white lines caused by localized pathology (e.g., edema from hypoalbuminemia) within the nail bed. Because they originate in the nail bed and not the nail plate, the lines do not migrate distally as the nail grows. The nail bed has abnormal vascular architecture that can be visualized microscopically. The lines disappear when pressure is applied to the nail plate because the abnormal blood supply is compressed 38

39 Nail bed morphology Morphology Onycholysis Tumors Benign Malignant Pincer nail Nail bed tumors Onychopapilloma Onychopapilloma is a benign tumor of the nail bed and distal matrix It is the most common cause of localized longitudinal erythronychia Characterized by localized distal subungual keratosis Thought that this tumor develops when the distal nail matrix differentiates precociously into nail bed epithelium with formation of a hyperplastic nail bed Dermoscopy of the free edge of the nail plate showing a small subungual keratotic mass where the band reaches the nail plate margin provides a clue for the diagnosis. The diagnosis of onychopapilloma can be made from a nail clipping provided it includes the entire distal nail plate. Histopathology shows a localized asymmetric keratotic portion underneath the free edge of the nail, comprised of layered hyperkeratosis Skin Appendage Disord 2017 Jan; 2(3-4): Nail bed tumors Malignant tumors Subungual tumors are rare Squamous cell carcinoma is the most frequent among all of the histological variants in contrast to basal cell carcinoma, which almost never affects nail beds Chronic infection, chemical or physical trauma/microtrauma, genetic disorders such as congenital ectodermal dysplasia, radiation, tar, arsenic or exposure to minerals, sun exposure, immunosuppression, and previous HPV infection have all been discussed as etiologic factors that may contribute to malignant transformation Open Access Maced J Med Sci 2017 Jul 25; 5(4 39

40 Clinical challenge This 25 year old male presented with a growing lesion on his distal index finger. He does not remember any injury. It is slightly tender and bleeds a lot. It has been present for only 2 weeks. Differential diagnoses Cellulitis Pyoderma gangrenosum Pyogenic granuloma Pyoderma vegetans Herpetic whitlow 40

41 Pyogenic granuloma is a rapidly growing vascular lesion that arises from minimal trauma and bleeds easily. The only satisfactory treatment is surgical removal. Nail bed tumor warts Periungual warts Nongenital warts occur in 7% to 10% of the general population, with the incidence peaking between the ages of 12 and 16 years. Viral warts occur equally in both sexes in children ages 2 to 12 years and are among the three most common dermatoses treated. Periungual warts occur anywhere along the nail margins, including the proximal nail fold and hyponychium, which can subsequently lead to onychodystrophy from nail matrix damage and onycholysis from nail bed warts. Nail biters commonly exhibit multiple periungual warts involving several nails. Nail bed tumor warts Medical treatments, usually topical, include keratolytic agents, virucidal agents, and immunomodulators. All choices have been utilized successfully, but keratolytic agents are the best first-line approach. Medical treatments Home remedies Hypnosis Garlic extract Duct tape Warts completely resolved in 85% of the duct tape arm of the study versus only 60% in the cryotherapy group Arch Pediatr Adolesc Med Oct; 156(10):971-4 Salicylic acid Cantharidin Since 1992, the drug is no longer available in the United States but can be purchased in Canada. Glutaraldehyde Formaldehyde Bleomycin IL Candida antigen 5-fluorouracil Cimetidine Imiquimod 41

42 Nail bed tumor warts Surgical treatments include cryotherapy, surgical excision, electrosurgery, infrared coagulation, localized heating with a radiofrequency heat generator and laser therapy Clinical challenge This 45 year old female was referred by another dermatologist for treatment of her warts (diagnosed on biopsy) with a laser since she had failed to respond to cryotherapy with liquid nitrogen. She is otherwise healthy with no history of immunosuppression. 42

43 Treatment options Repeat cryotherapy Intralesional bleomycin Laser treatment Repeat skin biopsy Duct tape Reviewing the outside pathology, which was not interpreted by a dermatopathologist, did not definitively show evidence of viral infection. On closer clinical inspection, it was felt that most of her disease was factitial and she did admit to constantly manipulating the affected area. Duct tape and treatment for OCD behavior would be the first treatment approach Pincer nails Pincer nail Pincer nail is a transverse overcurvature of the nail plate and may be inherited or acquired. The exact etiology is unknown, but the condition has been associated with betablocker use, psoriasis, onychomycosis, tumors of the nail apparatus, systemic lupus erythematosus, Kawasaki disease, and malignancy 43

44 Clinical challenge This 55 year old male was admitted for unexplained weight loss with GI symptoms for a malignancy workup. His evaluation was unremarkable. He gained weight while he was at the hospital but promptly started losing weight when he returned home. He was sent for a dermatology evaluation. Based on these nail changes where else would you look? Both hair and nail clippings were obtained showing excessive levels of arsenic. He had recently married a much younger woman and she did not manifest any of his symptoms. Clippings of her hair did not reveal any arsenic though they ate all their meals together. The local sheriff s office was alerted to get a search warrant. Dermatological changes are a common feature and the initial clinical diagnosis is often based on hyperpigmentation, palmar and solar keratosis. Hyperpigmentation occurs as diffuse dark brown spots, or less discrete diffuse darkening of the skin, or has a characteristic rain drop appearance A manifestation of arsenic deposition are prominent transverse white lines in the fingernails and toenails called Mee s lines. 44

45 The fortune teller can read the future in a palm but it is the physician who can read the past in a fingernail Walter Shelley Pediatr Dermatol Mar-Apr; 14(2): What you do in this world is a matter of no consequence. The question is what you make people believe you have done. Arthur Conan Doyle As quoted by Robert Baran Skin Appendage Disord 2017 Mar; 3(1): 2 6 THE END 45