Epithelial tumours
Epidermoid cysts of the distal phalanx are rare, usually secondary to trauma with implantation of epidermis into subcutaneous tissue or even into bone. An old trauma often goes unnoticed. The cyst may develop on a scar after surgery. The phalanx progressively expands and clubbing becomes obvious. The pain is of late onset, sometimes on the occasion of a pathological fracture. Histological investigation shows an epidermoid cyst filled with orthokeratin and lined with a thin layer of epidermis....
Nail melanoma
Melanoma of the nail apparatus most commonly derives from the matrix, much less frequently from the nail bed or hyponychium. Matrix melanoma usually causes longitudinal melanonychia see Chapter 5 . Whether atypical melanocytic hyperplasia is already subungual in situ melanoma is not entirely clear. Large, atypical melanocytes in all layers of the matrix and nail bed epithelium, pycnotic melanocytes in the nail plate mirroring the pagetoid spread in the epithelium, and mitoses, are seen as proof...
Melanocytic naevus of the nail organ
Naevi may be located at any site in or around the nail organ, and may pose considerable differential diagnostic problems when they cause longitudinal melanonychia. This sign may be due to a focus of functionally active melanocytes as in ethnic pigmentation , to an accumulation of active melanocytes as in the Laugier-Hunziker-Baran syndrome , or to a common lentigo, junctional melanocytic naevus, compound naevus or malignant melanoma. Most naevi are of the junctional type. A few barely visible...
Figure 1117
Sagging multilocated mucoid cyst arrowed of the proximal nail fold sagittal -weighted image. forms 22 it was not possible to detect a connection with the distal interphalangeal joint. These cysts may develop independently from the underlying joint and result from increased production of hyaluronic acid due to the metaplasia of fibroblasts. This process may be compared to the cutaneous myxomas with a focal storage of mucoid material in the dermis. Mucoid cyst of the proximal nail fold axial...
Sculptured artificial nails
Some natural nail keratin must be present for sculptured artificial nails to be used. The natural nail is first roughened with a burr, then painted with the acrylic resins which harden at room temperature and become moulded on to the nail. The prosthesis can be filed and manicured to shape. As the nail grows out, further applications of the self-curing acrylic resins can be made to maintain a regular contour. Allergic contact dermatitis may appear, generally after 2-4 months of application, as...
Veillonella infection in the newborn
Many epidemics of subungual infection have been described among infants in postnatal wards and special care baby units. The number of fingers affected per patient ranged from one to ten the thumbs are less frequently involved than other fingers toe nails are not affected. Three stages occur first, a small amount of clear fluid appears under the centre of the nail, along with mild inflammation at the distal end of the finger. This initial vesicle lasts approximately 24 hours it sometimes...
Local causes 1
The nail may be damaged by repeated trauma or by chemical agents such as detergents, alkalis, various solvents, sugar solutions and especially by hot water. The nail plate takes a minimum of 5-6 months to regenerate and therefore it is vulnerable to daily insults. Housework is commonly the cause particularly at risk are the first three fingers of the dominant hand. Anything that slows the rate of nail growth will increase the risk. Cosmetic causes are rare. Some varnishes will damage the...
Onychomycosis
Fungal infections of the nail organ are the most common nail disorders. Even though they are usually easily diagnosable they may be indistinguishable from nail psoriasis and the conditions may in fact occur together. Superficial white onychomycosis is easy to diagnose a tangential biopsy of the nail plate is taken with a no. 15 scalpel and sent to the laboratory. Formalin fixation is not necessary. The thin nail slice is processed and cut as usual and stained with periodic acid-Schiff reagent...
Further Reading Dzz
Alessi E, Zorzi F, Gianotti R, Parafiori A 1994 Malignant proliferating onycholemmal cyst, J Cut Pathol 21 183-188. Baran R, Goettmann S 1998 Distal digital keratoacanthoma a report of 12 cases and review of the literature, Br J Dermatol 139 512-515. Baran R, Kint A 1992 Onychomatrixoma. Filamentous tufted tumour in the matrix of a funnel-shaped nail a new entity, Br J Dermatol 126 510-515. Blessing K, Kernohan NM, Park KGM 1991 Subungual malignant melanoma. Clinico-pathological features of 100...
Pemphigus And Pemphigoid
The autoimmune bullous disorders do not exhibit specific features differentiating them from skin lesions. Pemphigus vulgaris may involve the matrix and nail bed with suprabasal acantholytic cleft formation and subsequent nail thinning. Bullous pemphigoid is characterized by a subepithelial cleft formation and an eosinophil-rich infiltrate. Cicatricial pemphigoid rarely involves the nail and may cause considerable nail dystrophy. Immunofluorescence examinations, sometimes enzyme-linked...
Onycholysis
Onycholysis detachment of the nail plate from the nail bed starts in the central or lateral portion of the nail plate free margin, progresses proximally and can even involve the whole nail. The onycholytic area looks whitish because of the presence of air under the detached nail plate. It may occasionally show a greenish or brown discoloration due to colonization of the onycholytic space by chromogenic bacteria Pseudomonas aeruginosa , moulds or yeasts. Onycholysis may be idiopathic or...
Ungual fibrokeratoma
Ungual fibrokeratomas may arise from the most proximal part of the matrix and remain in a supraungual position arise from the medial portion of the matrix and remain intraungual dissecting fibrokeratoma or arise from the distal matrix or nail bed growing entirely under the nail. The lesion is histologically characterized by a dense core of longitudinally arranged collagen, almost complete lack of elastic fibres, oedema in its acral part, and hyperkeratosis of the tip which usually includes...
Acrokeratosis paraneoplastica of Bazex and Dupre
Acrokeratosis paraneoplastica occurs in association with malignant epithelial tumours of the upper respiratory or digestive tracts, in particular the pharyngolaryngeal area piriform fossa, tonsillar area, epiglottis, hard and soft palate, vocal cords, tongue, lower lip, oesophagus and the upper third of the lungs. It also occurs with metastases to the cervical and upper mediastinal lymph nodes. This 'paraneoplasia' may precede the signs of the associated malignancy, disappear when the tumour is...
Further Reading Ihg
Alexander H, Miller DL 1979 Determining skin thickness with pulsed ultrasound, J Invest Dermatol T2 17-19. Baran R, Kechijian P 1989 Longitudinal melanonychia diagnosis and management, J Am Acad Dermatol 21 1165-1175. Baran R, Klint A 1992 Onychomatrixoma, Br J Dermatol 126 510-515. Bittoun J, Leroy-Willig A, Idy I et al 1987 Relation entre rapport signal-sur-bruit et param tres d'acquisition en IRM pour un contraste donn , Ann Radiol 30 5-13. Camirand P, Rowe WF 1970 Subungual glomus tumour....
Myxoid pseudocyst
Myxoid pseudocyst is one of the most frequent degenerative lesions of the nail area. Most commonly located in the proximal nail fold, it starts with a myxomatoid degeneration of the connective tissue which at first contains thin strands of loose connective tissue and stellate fibroblasts. The mucin masses eventually enlarge and compress the marginal connective tissue to form a denser pseudocapsule. Neither immunohistochemistry nor electron microscopy has revealed a cyst lining of synovial cells...
Nail wrapping
In nail wrapping the free edge of each nail is splinted with layers of a fibrous substance such as cotton wool, paper or plastic film affixed with a variety of glues after drying, the edge is fashioned to requirements and the nail is coated with enamel. The entire procedure is repeated every 2 weeks. Nail wrapping is useful but can do significant harm if the entire nail is covered because of the occlusive nature of the material used. Allergic reactions to cyanoacrylate nail preparations painful...
Onycholemmal horn
Onycholemmal horn is historically similar to proliferating trichilemmal tumour. Clinically the lesion has a warty appearance and histologically it consists of an epithelial proliferation with keratinocytes enlarging toward the surface and producing large amounts of keratin containing necrotic keratinocytes. There is no true crater and shoulder Keratoacanthoma is a fast-growing, painful lesion usually arising from the hyponychium or the lateral nail groove. In the tip of the digit it exhibits a...
Acquired longitudinal melanonychia after puberty in a whiteskinned individual
Approximately 2-3 of melanomas in whites, and 15-20 in blacks are located in the nail unit. However, malignant melanoma is rare in black people thus the number of nail melanomas does not significantly differ between these population groups. Most white patients have a fair complexion, light hair, and blue or hazel eyes. There is no sex predominance, although some reports show variable female or male predominance. The mean age at onset is 55-60 years. Most tumours are found in the thumbs or great...
Digital Herpes Simplex
Recurrent herpes simplex despite being rarely diagnosed is not infrequent. Any recurrent blistering process around a finger nail, particularly when accompanied by early lymphangitis and radiating pain, should prompt a cytological examination. The blister roof is opened and a Tzanck smear taken for microscopic investigation as well as for virus culture or molecular biological tests. Early blisters with clear watery contents exhibit mainly keratinocytes, some of which are giant and...
Keratin cysts
Various types of keratin-filled cysts may occur under or around the nail. Traumatic implantation cysts are lined by epidermis and contain orthokeratin. Intraosseous implantation cysts demonstrate the same histological features. Nail surgery that displaces matrix and or nail bed epithelium may give rise to a cyst in which parts of the wall reveal exactly the same structure as a trichilemmal cyst it might well be called an onycholemmal cyst and which contains compact eosinophilic keratin...
Brittle Nails
Nail brittleness causes several clinical symptoms including splitting, softening, lamellar exfoliation and onychorrhexis. Brittle nails are a common complaint. It is often an idiopathic condition, but can also be a symptom of a large number of dermatological nail disorders. Although brittle nails have been linked with many internal diseases, the high frequency of nail fragility in the general population makes it difficult to prove the validity of any such association. Environmental and...
Melanoticmelanocytic lesions
Benign melanocytic hyperplasia Lentigo simplex and naevocytic naevus Atypical melanocytic hyperplasia Peutz-Jeghers-Touraine syndrome Malignant melanoma Subungual warts are painful and may mimic glomus tumour. The nail plate is not often affected, but surface ridging may occur and, more rarely, dislocation of the nail. Biting, picking and tearing of the nail and nail walls are common habits in people with periungual warts. This type of trauma is responsible for the spread of warts and their...
Onychogryphosis
Chemical avulsion of the overgrowing nail plate with urea ointment is useful and provides considerable relief of the patient's discomfort. Different formulations can be used, ranging from a simple 40 urea in 60 white petrolatum preparation, to the South and Farber's ointment, which has the following formulation urea 40 , white beeswax 5 , anhydrous lanolin 20 , white petrolatum 25 , micronized silica gel 10 . Before the ointment is applied to the nail plate surface, it is mandatory to cover the...
Further reading Gln
Nail disorders are rarely subjected to thorough histopathological investigation. In contrast to skin, the nail is not easy to biopsy and many physicians as well as patients are therefore reluctant to undertake this procedure. To obtain relevant results it is necessary to consider the following 1 Nail changes usually reflect a pathological process of the matrix or much less frequenly of the nail bed. The biopsy must contain a relevant piece of matrix. 2 Some changes that are obvious to the naked...
Squamous cell carcinoma of the nail apparatus has a good prognosis compared
Trauma, chronic infection and chronic radiation exposure are possible aetiological factors human papillomavirus HPV has been incriminated in some cases. Two reported cases had associated congenital ectodermal dysplasia. Most lesions occur on the fingers, particularly the thumbs and index fingers Figure 5.31 . The presenting symptoms include pain, swelling, inflammation, elevation of the nail, ulceration, a tumour 'mass', ingrowing of the nail, 'pyogenic granuloma' and bleeding. Bone involvement...
Hard Nails
Hard nails are not uncommon on the toes, where they may present as onychogryphosis. In contrast, hard finger nails are unusual and are principally observed in an ectodermal dysplasia, pachyonychia congenita. The nails become yellowish-brown usually within months after birth and show subungual hyperkeratosis with elevation of the nail plate. The nails become progressively thicker and wedge-shaped. Jadassohn had to use a hammer and chisel on the hardened nails of his patient. Nail hardness is one...
Periungual Warts
Periungual and subungual warts are usually difficult to treat and frequently recur. The life span of periungual warts may be such that they and the various treatments may exceed the patience of both patient and physician Under such circumstances intelligent placebo therapy may well be appropriate. A great variety of treatments are listed in all pharmacopoeias, reflecting their individually limited success rates. The choice of treatment depends on location periungual and subungual
Epoxy resin dermatitis Occupational Figure 53 Dermatoses
Acrodermatitis enteropathica Figure 5.6 Hallopeau's acrodermatitis Ingrowing toe nail Lichen planus Pachyonychia congenita Parakeratosis pustulosa Pemphigus Psoriasis-Reiter's syndrome Figure 5.7, 5.8 Radiodermatitis Yellow nail syndrome Systemic disease Antiretroviral drugs Cytotoxic drugs Collagen vascular diseases Figure 5.9 Paraneoplastic acrokeratosis Sarcoidosis Figure 5.10 Stevens-Johnson syndrome Toxic epidermal necrolysis Vasculitis Zinc deficiency Figure 5.11 Miscellaneous...
Figure 951
7 Multiple transverse leukonychia Figure 9.52 . Multiple transverse white bands margins separated by normal pink nail and paralleling the distal shape of the lunula result from repeated microtrauma. These appear in patients with marked visible free of the involved toe nails usually the great toe or the second toe when longer , indicating a lack of trimming and impinging on the distal part of the shoe. Transverse leukonychia from distal pressure on untrimmed nail. Transverse leukonychia from...
Trauma
Childhood malalignment Cold injury Common type Crush and squeeze injuries Ingrowing toe nail Splinters, foreign bodies Sports and sport shoe injuries Inflammation Acro-osteolysis Herpes simplex Implantation epidermoid cyst Osteomyelitis Pincer nail severe form enclosing bone Post-cryosurgery may be prolonged bone pain Prosector's wart tuberculosis Sarcoid dactylitis Subcutaneous abscess Subungual foreign body Ventral pterygium Tumours soft tissue and bone Aneurysmal bone cyst Bowen's disease...
Figure 57
Chronic paronychia in psoriasis. Squeezing the nail fold produces a cheesy material Sabouraud's medium negative . Chronic paronychia in psoriasis. Squeezing the nail fold produces a cheesy material Sabouraud's medium negative . Chronic granulomatous paronychia due to sarcoidosis. Courtesy of J. Hewitt. Chronic granulomatous paronychia due to sarcoidosis. Courtesy of J. Hewitt.
Bowens disease epidermoid carcinoma
Bowen's disease is a term for intra-epithelial squamous carcinoma Figures 5.30-5.32 . It is not as rare as might be inferred from the medical literature. Epidermoid carcinoma subungual involvement. Epidermoid carcinoma subungual involvement. a Epidermal carcinoma b epidermal carcinoma, with nail plate trimmed back to show extension of invasion. Courtesy of G. Cannata, Italy. a Epidermal carcinoma b epidermal carcinoma, with nail plate trimmed back to show extension of invasion. Courtesy of G....
Further Reading 1
Finlay AY, Frost P, Keith AD et al. An assessment of factors influencing flexibility of human fingernails. Br J. Dermatol 1980 103 357-365. Flowersheim GL. Behandlung br chiger fingern gels mit biotin. Zschr Hautkr 1991 64 31-48. Lubach D, Beckers P. Wet working conditions increases brittleness of nails, but do not cause it. Dermatology 1992 185 120-122. Saniman P. Nail disorders caused by external influences J Soc Cosm Chem 1977 28 351-356. Brosch T, Pressler S, Platt D. Age-associated changes...
Nail apparatus melanoma has a poorprognosis with up to 50 of patients dying
Subungual melanoma has a poor prognosis. The reported 5-year survival rates range from 35 to 50 . Most patients present with advanced subungual melanoma however, even early diagnosis is not a guarantee of a good prognosis. Women have a better prognosis than men. Factors contributing to a poor prognosis are delay in diagnosis and, as a result of this, inadequate treatment. The tumour may be mistaken for a traumatic dystrophy, and valuable time may be lost before the diagnosis is made. Treatment...
Nail abrasion
Thick nails caused by diseases such as psoriasis, pityriasis rubra pilaris and pachyonychia congenita can be abraded. Hyperkeratosis is prone to be associated with onychomycosis of the toes. Nail abrasion helps to expose the nail bed to antifungal chemicals, especially in elderly people in whom systemic treatment is not advisable. Abrasion is a good way to improve the contour of an abnormal nail, for example in onychogryphosis. In selected cases of ingrowing toe nail, repeated thinning of the...
Malignant
Bowen's disease_Features clinically typical of subungual melanoma After Baran and Kichijian 1996 . LM, longitudinal melanonychia. a, b Malignant melanoma amelanotic. a, b Malignant melanoma amelanotic. without a history of severe trauma. It may follow repeated minor trauma which escapes the patient's attention, such as in 'tennis toe', or follow trauma from wearing hard ski boots. Although haematoma following a single traumatic event usually grows out in one piece, rather than as a longitudinal...
Figure 957
a Acute paronychia with pus tracking into the nail bed b treatment by transverse section of the nail plate. Radiodermatitis and radionecrosis of the bony phalanx following treatment of epidermal carcinoma. Radiodermatitis and radionecrosis of the bony phalanx following treatment of epidermal carcinoma. Implantation cyst following surgical treatment for ingrowing toe nail. Implantation cyst following surgical treatment for ingrowing toe nail. pulp, is richly innervated. Each 'space-occupying'...
Tumours of the perionychium
In the authors' institution the main indications for MRI are vascular tumours and mucoid cysts. Numerous other lesions are explored, such as epithelial tumours warts, epidermoid cysts, onychomatricomas, keratoacanthomas , soft-tissue tumours fibrokeratomas, fibromas, tenosynovial giant cell tumours , and osteochondral lesions exostoses, chondromas, osteoid osteomas, chondrosarcomas . The accurate location of the tumour with MRI associated with its signal patterns is important for diagnosis....
True leukonychia
In this rare condition Figure 7.1 the nail may be milky, chalky, bluish, ivory or porcelain white in colour. The opacity of the whiteness varies when it is faintly opaque, it may be possible to see transverse streaks of leukonychia in a nail with total leukonychia. A transition to black has been observed in the distal nail plate portion in patients suffering from severe cholestatic jaundice. Accelerated nail growth may be associated with total leukonychia.
Ultrasonography
Ultrasonography should be more widely used in imaging the nail unit. However, its dependence on operator skills and the moderate experience of radiologists in this anatomical region are limiting factors. High-frequency 7.5-20 MHz probes dedicated to musculoskeletal or skin imaging are suitable. An inter-position material is necessary for the study of the most superficial structures. The nail bed presents a somewhat homogeneous hypoechoic appearance, separating the high-intensity echoes of the...
Periungual and subungual warts
Common warts are caused by human papillo-maviruses of different biological types Figures 5.16-5.18 . They are benign, weakly infective, fibre-epithelial tumours with a rough keratotic surface. Usually periungual warts are asymptomatic, although fissuring may cause pain. Subungual warts initially affect the hyponychium, growing slowly toward the nail bed and finally elevating the nail plate. Bone erosion from verruca vulgaris occasionally occurs although some of these cases may have been...
Chronic paronychia is not a primary infection Chronic paronychia of the hands
of clothes. Clinically, the proximal and lateral nail folds show erythema and swelling. The cuticle is lost and the ventral portion of the proximal nail fold becomes separated from the nail plate. This newly formed space has an important additional role in maintaining and aggravating chronic paronychia it becomes a receptacle for microorganisms and environmental particles that potentiate the chronic inflammation. With time the nail fold retracts and becomes thickened and rounded. The course of...
Dermatological
Amyloid primary Basal cell carcinoma Bacterial infection Bowen's disease Fungal infection Laugier-Hunziker-Baran syndrome Lichen planus Malignant melanoma Peutz-Jeghers-Touraine syndrome Porphyria cutanea tarda Radiotherapy and radiodermatitis Regional and local Carpal tunnel syndrome Repeated minor injuries Friction significant abnormalities can produce brown or black discoloration Table 7.2 . Most of the causes will be self-evident at the time of presentation, either from the history or on An...
Myxoid pseudocysts of the digits
The many synonyms for mixed pseudocyst of the digits reflect the controversial nature of this lesion dorsal distal interphalangeal joint ganglion digital mucinous pseudocyst focal myxomatous degeneration Whereas some authors regard it as a synovial cyst, most now believe it to be a periarticular degenerative lesion. Myxoid cysts occur more often in women. They are typically found in the proximal nail fold of the fingers and rarely on toes Figures 5.27-5.29 . Usually asymptomatic, these lesions...
Figure 948
Nail shedding in a long-distance runner. self-inflicted anonychia of the toe nails is associated with small or absent nails and crushing due to traumatic bleeding periodic shedding of the nails can result from biomechanical causes and is frequently seen in runners. Worn-down nail Figures 9.49, 9.50 see Chapter 2 koilonychia toes of rickshaw pullers 4 Brittle nails see Chapter 6 . 5 Onychogryphosis and hypertrophic nail see Chapter 4 . 6 Frictional melanonychia Figure 9.51 frictional...
Ethnic nail pigmentation
Ethnic nail pigmentation is usually easy to recognize by its familial inheritance and the polydactylic distribution of the bands. When observed with epiluminescence microscopy the bands have a fairly homogeneous grey background and thin grey lines comparable with those observed in lentigo Figure 12.10 . Ungual lentigo in an adult's finger nail. Dermoscopy reveals a Ungual lentigo in an adult's finger nail. Dermoscopy reveals a relatively homogeneous greyish background between the two short...
Ragged Cuticles And Hangnail
Thickened, hyperkeratotic, irregular ragged cuticles Figure 5.12 are most commonly seen in dermatomyositis Figure 5.13 . Perionychial tissues are constantly subjected to trauma. In nail biters and 'pickers' the cuticles and nail folds may show considerable damage, erosions, haemorrhage and crusting. The ulnar side of the nail fold and cuticle is most vulnerable and there may be small trian-gular tags of skin hangnail, Figure 5.14 and separated spicules of nail, still attached proxi-mally....
Alteration of the nail itself
This category includes 1 Self-inflicted injury Figures 9.45-9.47 the habit of pushing back the cuticle see Chapter 2 Heller's median nail dystrophy see Chapter 2 self-inflicted nail damage may cause longitudinal melanonychia LM nail artefacts, caused by deliberate acts of injury to the nail apparatus with the intention of creating a 'diversion for personal gain' they may also be caused 'subconsciously'. Nail artefacts take various forms. Such patients usually have psychological problems....
Fragile Brittle And Soft Nails
Many of the nail diseases that disrupt nail formation and structure cause secondary brittleness and fragility. In this chapter only those conditions leading to nail fragility or brittleness as a major sign are considered in any detail Figures 6.1-6.7 . 'Hapalonychia' is the term used for cryptogenic soft nail cases for which there is no primary specific local nail disease to explain the change. Diseases and conditions associated with this include
Magnetic Resonance Imaging
There have been a few reports of MRI investigations of subungual tumours, particularly glomus tumours. In practice the perionychium may be routinely imaged by MRI with the ability to obtain high spatial resolution images with small surface coils dedicated to wrist or finger Figure 11.3 . A voxel height close to 100 m, about the thickness of the epithelial layer of the nail bed, is necessary. Nevertheless, unlike the skin, which is a superficial structure, the nail unit may require evaluation of...