Disorders of the nails

Professor Danka Švecová MD, PhD Dept.of Dermatovenerology Faculty of Medicine, Comenius University Disorders of the nails

Nail complex – a structural and functional unit; consists of→ the plate, bed, matrix, proximal and lateral and distal grooves, proximal and lateral folds, hyponychium

Healthy unit – important function → protection of the distal phalanges, fingertip and surrounding soft tissue from external injury; precise delicate movement of the distal digits Disorders of the nail plate Spontaneous separation at distal free margin; progressing to the proximal edge; less often separation of nail plate begins at the proximal nail and extends to its free edge (psoriasis of the nails - onychomadesis)

Exogenous causes → repetitive minor mechanical trauma or maceration (water, sugar onycholysis in confectioners) allergic reaction triggered by various nail cosmetics Disorders of the nail plate Onycholysis

Endogenous causes → iron deficiency, anemia, diabetes mellitus, hyperthyroidism, hypothyroidism, pregnancy, scleroderma, pemphigus vulgaris

The most common skin diseases associated with onycholysis → psoriasis, , contact dermatitis, atopic dermatitis Disorders of the nail plate Onychorhexis „Brittle nails“- brittleness with breakage of nails may result from dryness of the nails

Causes → excessive strong soap, water exposure, nail polish remover, hypothyroidism, after oral retinoid therapy; vitamin B deficiency, iron deficiency, malnutrition; 20% of population Disorders of the nail plate Onychogryhosis „claw or talon nails“ Causes → trauma, peripheral vascular disorder, neglection of trimming the nails for a very long period

Predisposing factors → chronic venous insufficiency, anatomic anomalies (halux valgus), association with some disorder of keratinization; long term pressure exerted on the nails from shoes Disorders of the nail plate Onychogryhosis

Thickened nail plate → brownish-grey with rough surface, rounded along its longitudinal axis resembling a claw, the nail becomes distorted by growing away from its bed; it is impossible to trim the nail;

The toes nails of elderly patients are affected, fingernails less Disorders of the nails Thin and concave nails with everted edges „spoon-like shape“; often combine with several or even all nails are affected Causes → nutritional deficiencies → iron; in Raynaud disease, peripheral vascular diseases, repetitive mechanical or chemical damages, familial forms Disorders of the nails Platonychia The nails are flat and broad;

Causes → trauma, chronic nail bites, thyroid disease, vitamin deficiencies; transitory stage between a normal nail and koilonychia Disorders of the nails Onychodystrophy

Damage incurred to the nail matrix → apparent as the nail grows distally Disorders of the nails Onychodystrophy Beau´s lines → transverse furrows; begin in the matrix; progress distally as the nail grows one or more convex transverse lines run across the nail bilateral or unilateral Causes → acute febrile illness, drug reactions, , psoriasis, erythroderma; minor repetitive trauma to the nail fold and cuticule →horizontally ridged nails (chronic manipulation of cuticule, recurrent paronychial infections Disorders of the nail plate Median canal dystrophy

Longitudinal splitting or canal formation in the midline of the nail; the split may resemble a fir tree occurs at the cuticle and precedes outward as the nail grows usually the thumbnails are involved;

Causes → idiopathic, may bee inherited; repetitive trauma, it persists for years Changes of the nail color

„white nails“→ congenital or acquired Leukonychia punctata - most common form, otherwise normal nails; may follow a current episode of trauma Leukonychia striata – may be hereditary, trauma or systemic origin Partial leukonychia – associated with tuberculosis, nephritis, Hodgkin´s disease, metastatic carcinoma, leprosy, or idiopathic Changes of the nail color Leukonychia

Leukonychia totalis associated with typhoid fever, leprosy, cirrhosis majority of cases → idiopathic whitening appears spontaneously or due to minor trauma; white color is due to incomplete keratinisation, and subsequent retention of nuclear debris in the nail plate Changes of the nail color Leukonychia

Mees lines → transverse lines of the same color as lunula; cause → arsenic poisoning, thallium poisoning, or sudden nail matrix damage Changes of the nail color Leukonychia

Longitudinal white strakes → in Darier´s disease

DifDg – whitening of other origin: fungal infection, pallor of the nail bed in hypalbuminemia Changes of the nail color Half-and-half nails

Half-and-half nails → associated with renal diseases

The proximal nail bed is white and the distal half is red-brown Changes of the nail color Marked thickening and yellow to yellowish green discoloration of the nails Nails are over-curved both transversely and longitudinally grow very slowly, often onycholysis In systemic disease→ compromised respiration and lymphoedema Changes of the nail color Terry nail Terry nail → proximal end or the entire nail plate has white appearance → result of changes in the nail bed the distal nail is of normal pink colour Systemic disorders → cirrhosis, hypalbuminaemia, chronic congestive heart failure, in very elderly patients Paronychia disorders Paronychia

Soft tissue infection around a fingernail it results from a breakdown of the protective barrier between the nail and nail fold →results in bacterial or fungal colonization of the area;

Risk factors → diabetes mellitus, obesity, hyperhidrosis, immunologic defects, drug-induced immunosuppression Paronychia disorders Acute paronychia history of minor trauma to the fingertip or by nail manipulation painful, tenderness and swelling in one of the lateral folds of nail, Staphylococcus aureus → causative agent Paronychia disorders Chronic paronychia six weeks or longer; inflammation, pain, swelling – episodically after an exposure to water or moist environment, tender nail folds without fluctuation, cuticles and nail folds may separate from the nail plate, forming a space for the invasion of various microorganisms; Candida albicans → causative agent most often Paronychia disorders Chronic paronychia most often on the hands in person repeatedly exposed to moist environments, prolonged and repeated contact with irritants → housekeepers, dishwashers, bartenders, swimmers; Skin disorders → psoriasis, mucocutaneous candidiasis, drug toxicity e.g. retinoids (Unguis incarnatus)

Ingrown nail results from an alteration in the proper fitting of the nail plate in it´s usual nail groove

Sharp spicule of the nail lateral margin → drives into the dermis of the nail groove →the nail acts as a foreign body Ingrown nail (Unguis incarnatus)

Nail as a foreign body → inflammatory response – erythema, edema, focal tenderness, later crusting, purulence at the nail fold and nail plate junction → protuberant granulation tissue extends over the nail plate; Ingrown nail (Unguis incarnatus)

Generally it occurs of poorly fitted footwear

Prior trauma resulting in an irregularly shaped nail, painful, the discomfort worsens with weight bearing and ambulation Nail changes associated with systemic disorders

Impaired peripheral circulation ( e.g. Raynaud disease) thinning – flattening or koilonychia; onycholysis; white color in contrast →impaired circulation in older persons → thickening of the nail plate with onycholysis; Acute digital ischemia may cause „blue nails“ Lymphoedema →yellow nail syndrome no lunula Nail changes associated with systemic disorders

Chronic pulmonary disease →clubbing – bulbous, club-like deformation of the distal portion of fingers and toes from connective-tissue proliferation; later, the distal phalanx becomes enlarged → increase in size →not specific →idiopathic, familial, or associated with billiary cirrhosis, ulcerative colitis Nail changes associated with systemic disorders

Gastrointestinal disease malabsorption leading to malnutrition → horizontal ridges or altering bands of discoloration, lunula may be absent Renal disease half-and-half nails, about 30% of dialysis patients have no lunula