Nail disorders Flashcards
The difference in pitting between alopecia areata and psoriasis?
Irregular spaced in psoriasis and in alopecia areata, it is rather organized and symmetric.
What are Beau’s lines?
Transverse depressions of nail plate.
What causes Beau’s lines?
A temporary disruption in mitotic activity in proximal nail matrix
What is the most common cause of Beau’s lines?
Mechanical trauma or dermatologic dz of proximal nail fold (eczema, psoriasis, paronychia)
What is the cause of Beau’s lines if all the nails are involved?
Systemic cause (febrile illness, drugs)
What is onychomadesis?
Nail shedding
What is the pathophysiology of onychomadesis?
A proximal detachment of nail plate, due to complete arrest of nail matrix activity (causes are the same as beau’s lines)
Pathophysiology of nail pitting?
Parakeratosis on the proximal nail matrix
Causes of pitting?
Psoriasis, alopecia areata, lichen planus, and eczema
What disease is pitting most specific for?
Alopecia areata
What is the difference between the nail pitting in psoriasis vs alopecia areata?
In psoriasis, it is more haphazard and centrally oriented. In alopecia areata, it is more evenly spaced and involves the lateral nail.
What is onychorrhexis?
Longitudinal ridges and fissures with thinned nail plate
What causes onychorrhexis?
Due to diffuse nail matrix dz, trauma, tumors compressing nail matrix, others
Mild longitudinal ridges are common features of aging
What is trachyonychia?
Twenty nail dystrophy/sandpaper nails, opaque, lusterless and rough nails
Most common things associated with trachyonychia?
Alopecia areata (most common), LP, psoriasis, and eczema
What is true leukonychia?
White, opaque discoloration due to parakeratotic cells on ventral plate (most common cause trauma)
Types of true leukonychia?
Punctate, striate, or diffuse
What is pseudoleukonychia?
Friable, fungi in nail plate with superficial white onchyo
What is apparent leukonychia?
Discoloration, nail bed edema, due to hypoalbuminemia or chemotherapy drugs
What is koilonychia?
spoon nails, thinned concave nails.
Causes of koilonychia?
Physiologic in toenails of kids, occupational or severe iron deficiency in adults
What is onycholysis?
Distal nail plate detachment
What causes onycholysis?
Trauma, psoriasis, or onychomycosis
Pigmentation in onycholysis is due to?
microbial colonization or blood
What is photo-onycholysis?
UV light alone or in combo with (tetracycline)
What are the 6 main things associated with onycholysis?
enviromental, primary skin diosrders, infections, drugs, metabolic/systemic disorders, tumors
What metabolic conditions can lead to onycholysis?
hyperthyroidism
What is onychauxis?
Thickened nail ue to subungual hyperkeratosis?