This document provides a pictorial guide to nail abnormalities and their associated conditions and diseases. It discusses various nail disorders including fungal infections, trauma-related injuries, deficiencies, genetic disorders, infections, and more serious conditions like melanoma. Each abnormality is accompanied by a brief description and list of potential causes or associated systemic illnesses. The guide aims to help identify nail issues and their underlying etiologies.

1. A Pictoral Ddx for Nail Health
-What do your nails say about you?

2. Anatomy:

3. Infectious:

4. Onychomycosis
(fungal infection)
• Tinea unguium - 50% of
all nail infections; nail
can turn white, yellow,
black or green, thicken,
become chalky, and
crumble (caused by
Trichophyton rubrum or
T. mentagrophytes)
• These fungi cause
ringworm of the skin

5. Onychomycosis - progression

6. Onchomycosis
• Yellowing and
thickening due to
Monilia - yeast
infection

7. Paronychia
(Infection around the nail bed)
• Staph or Strep infection
often associated with
nail biting, manicuring,
or frequent water
immersion

8. Onychia
(inflammation and pus around nail
folds)
Associated condition:
• Microscopic pathogens
that enter through
small wounds
*Often associated with
ingrown nails

9. Inflammatory:

10. Nail Pitting
• Sarcoidosis
• Psoriasis
• Chemical dermatitis
• Alopecia

11. Cuticle Invasion
Associated Condition:
• Lichen Planus

12. Transverse Ridging
Associated Conditions:
• Atopic dermatitis
• Psoriasis
• Parakeratosis (increased
cell turnover causing
thinning)

13. Onychorrhexis
(brittle nails)
Associated Conditions:
• Atopic Chemical exposure
(strong soaps, nail polish
remover, formaldehyde, etc)
• Hypothyroidism
• Anemia
• Malnutrition
• Oral retinoid therapy
(treatment for
keratinization disorders)
• Darier’s Disease (genetic;
associated with skin rash)

14. Onychoschiza
(Nail Splitting)
Associated Conditions:
• Psoriasis
• Folic Acid deficiency
• Vitamin C deficiency

15. Trachyonychia
(Sand-paper nails)
Associated Conditions:
• Lichen planus
• Tight shoes/heels

16. Cuticle Invasion - Pterygium
Associated Condition:
• Lichen planus
• Trauma
• Steven Johnson
Syndrome

17. Other:

18. Distal Onycholysis
(detachment from the the nail bed)
Associated Conditions:
• Fungal infection
• Trauma / excess manicuring
• Hyperthyroidism
• Peripheral ischemia
• Photosensitive drug reactions
• Atopic dermatitis
• Amyloidosis
• Connective tissue disorders
• Psoriasis
• Bronchiectasis
• Syphilis
• Hyper and hypothyroidism
• Raynaulds
• Hepatocellular dysfunction

19. Trauma:

20. Onchogryphosis
(Ram’s Horn nails)
Associated Conditions:
• Peripheral Vascular
Disease
• Trauma
• Failure to cut nails
*Often seen in the elderly

21. Subungual Hematoma
Associated Condition:
• Blood pools under the
nail(hematoma) due to
acute injury or
repetitive
• Painful
*Note: treatment involves
drilling a hole in and
releasing the blood

22. Onychoptosis
(nail shedding)
Associated conditions:
• Trauma
• Syphilis
• Hand Foot and Mouth
disease
• Fever
• Drug reactions

23. Deficiencies:

24. Koilonychia
(spooning)
Associated Condition:
• Iron deficiency anemia

25. Leukonychia
(white spots)
Associated Conditions:
• Vigorous and repeated
manicuring
• Zn deficiency
• Calcium deficiency
• Sickle cell anemia

26. Vertical Ridges
Associated Conditions:
• Hypochlorhydria
(associated with aging)
• Rheumatoid arthritis
(more severe ridging)

27. Muehrcke’s Lines
(hypopigmentation below the nail and
without ridges )
• Decreased protein
synthesis (metabolic
stress, chemotherapy)
• Increased protein loss /
hypoalbuminemia
(Nephrotic Syndrome)
• Malnutrition

28. Genetics:

29. Ectodermal dysplasia / Anonychia
congenital
(absence of nails)
• Genetic disorder
affecting the
development of teeth,
hair, nails, and sweat
glands)

30. Mental / Emotional:

31. Bitten nails
• Onychotillomania –
compulsive picking or
tearing off of nails
• Onychophagia – nails
are bitten and chewed
off due to anxiety
• Dermatillomania – the
skin around the nail is
bitten or scratched

32. More serious conditions:

33. Brown-gray Nails (Melonychia)
Associated Conditions:
• Cardiovascular disease
• Diabetes mellitus
• Vit B12 def
• lichen planus
• Syphilis
• Atopic dermatitis (hair dye,
varnish, formaldehye, etc)
• Inflammatory disorders
• Breast cancer
• Malignant melanoma
• Addison’s
• Nicotine use (smoking)

34. Green-black nails (chromonychia)
Associated Condition:
• Candida infection
• Pseudomonas infection
(m/c is P. aeruginosa)
*note: black is most
common associated with
pseudomonas

35. Dark longitudinal lines on nails
Associated Conditions:
• Repetitive trauma
(running in small shoes)
• Systemic and
inflammatory disorders
• Trauma
• Fungal infections
• Drug reaction
• Subungual melanoma
• Benign melanocytic
hyperplasias

36. Splinter hemorrhage
Associated Conditions:
• Bacterial Endocarditis (if
left untreated can lead
to heart failure)

37. Red Nails
Associated Conditions:
• Polycythemia (dark red)
• Lupus
• Carbon Monoxide
(cherry red)
• Angioma
• Malnutirion

38. Longitudinal Erythronychia
(red bands)
Associated conditions:
• Dariers Disease
• Lichen Planus

39. White Nails (Terry’s Nails)
Associated Conditions:
• Anemia
• Renal failure
• Liver cirrhosis
• Congestive heart failure,
• Diabetes mellitus
• Chemotherapy
• Genetic (rare)
*anything causing
decreased blood flow to the
nails.

40. Half & half Nails
(white at the base)
Associated Condition:
• Hepatic necrosis

41. Yellow Nails
Associated Conditions:
• Yellow nail syndrome
(associated with swelling
in other parts of the
body)
• Amyloidosis
• Jaundice
• Diabetes mellitus
• Median/ulnar nerve
injury
• Bronchiectasis
• Thermal injury

42. Beau’s Lines
(horizontal ridges in the nail plate)
Associated Conditions:
• Systemic conditions like
Raynauds (especially
after cold exposure)
• Pemphigus
• Trauma
• Uncontrolled diabetes
• Infectious: scarlet fever,
measles, mumps,
pneumonia

43. Mees’ Lines
(discoloration in the nail plate)
Associated Conditions:
• Arsenic poisoning
• Heart failure
• Hodgkins
• Carbon monoxide
poisoning
• Chemotherapy
• Leprosy

44. Clubbing
Associated Conditions:
• Heart and Lung diseases
• Gastrointestinal and
Liver diseases
(malabsorption, crohns,
colitis, cirrhosis)
• Graves Diseases
• Malignancy
*red line = clubbing

45. Onychomatricoma
(tumour of the nail matrix)
• Make sure to biopsy this
one as it can mimic
many other pathologies