There are a variety of common conditions that patients bring to their doctor's attention. Longitudinal ridging is a normal feature of aging. Splitting of the ends of the nails is due to trauma and too much water exposure. Separation of the nail from the nailbed is also due to excess wet work where the bonds between the nail and the underlying nail bed are weakened and the nail separates. This is known as onycholysis. Any candida found under the separated nail is a contaminant.Nails are solid keratin which is the food for dermatophyte fungii. Hence most crumbly nails are due to a dermatophyte infection but some may be due to psoriasis. Take nail clippings for culture. Nail distortion is commonly due to ageing and poorly fitting shoes.
Specific conditions involving the nails
Brittle Brittle nails
Curved Koilonychia,Pincer nails
Dystrophic Darier's disease,Lichen striatus,Psoriasis,Onychomycosis,Onychophagia,Proximal subungual onychomycosis,Trachyonychia,
Groove Digital mucous cyst
Malaligned Congenital malalignment
Onycholysis Onycholysis,(numerous causes,water,photodrug etc),Onychomycosis,Psoriasis,Traumatic,Epidermolysis bullosa aquisita,Pemphigus vulgaris,Acropustulosis of Hallopeau
Pigmentation Drug induced(AZT,Bleomycin,Methotrexate),Longitudinal melanonychia
Pits Alopecia areata
Purpura Splinter hemorrhages,Subungual hematoma
Ridges longitudinal Aging,Lichen planus,median nail dystrophy
Ridges transverse Beau's lines,Chronic paronychia,Habit nail tic deformity,
Short Brachyonychia
Thickened Chronic mucocutaneous candidiasis,nail hypertrophy and Onychogryphosis,Onychauxis,Onychomycosis,Pachyonychia congenita,Psoriasis
Coloured Blue(Blue nails drugs or Wilson's disease),Green (Pseudomonas),White(Half and half nails,Leukonychia,Muehrcke's lines,Terry's nails,White superficial onychomycosis),Yellow (Nail discoloration cigarretes,Yellow nail syndrome)
Posterior nail fold Paronychia,Chronic candidiasis,Scleroderma,Dermatomyositis (ragged cuticles)
Modified from Regional Dermatology Gary M White
