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ULY CLINIC

24 Septemba 2025, 14:59:08

Subungual hemorrhage

Subungual hemorrhage refers to bleeding beneath the nail plate, often presenting as linear or diffuse reddish-brown streaks. Linear hemorrhages, known as splinter hemorrhages, extend from the distal edge toward the proximal nail fold. Subungual hemorrhages may result from systemic diseases, trauma, or infections.

Pathophysiology

Splinter hemorrhages occur when capillaries in the nail bed rupture, releasing blood beneath the nail plate.
Causes include:
- Infective endocarditis: Microemboli damage nail bed capillaries.
- Systemic infections: Trichinosis may produce similar capillary damage.
- Trauma: Direct injury to the nail matrix or bed produces larger, localized hemorrhages.
The appearance and pattern help differentiate systemic causes from localized trauma.

Examination Technique

Inspection: Ask the patient to extend the fingers and toes. Observe all nails for:
- Linear streaks (splinter hemorrhages)
- Diffuse subungual blood accumulation
Lighting: Use bright light to enhance visualization.
Documentation: Record:
- Number of nails involved
- Distribution (fingernails vs. toenails)
- Pattern (linear, diffuse, or punctate)
Additional assessment: Consider cardiac auscultation if infective endocarditis is suspected.

Clinical Features

Feature	Manifestation
Appearance	Thin, linear, reddish-brown streaks (splinters) or larger diffuse areas
Distribution	Often fingernails in systemic disease; toes more in trauma
Onset	Subacute for systemic disease; acute after trauma
Associated symptoms	Fever, malaise, or signs of systemic infection if underlying disease present
Pain	Usually absent unless due to trauma

Differential Diagnosis

Condition	Key Feature	Notes
Subacute bacterial endocarditis	Multiple splinter hemorrhages in fingernails	Often accompanied by fever, heart murmur, or systemic symptoms
Trauma	Single or few nails with hemorrhage	History of crush, nail injury, or repeated friction
Trichinosis	Splinter hemorrhages with myalgia, fever	Associated systemic infection signs
Psoriasis / Nail dystrophy	Pitting or onycholysis with occasional streaks	Usually chronic, with other skin manifestations
Vasculitis	Nail bed hemorrhages with other purpura	Systemic inflammation signs present

Pediatric considerations

Splinter hemorrhages are rare in children unless secondary to trauma or systemic infection.
Always assess for signs of infective endocarditis or vasculitis.

Geriatric considerations

Older adults may have vascular fragility, increasing risk for trauma-related subungual hemorrhages.
Consider underlying cardiovascular disease if multiple nails are involved.

Limitations

Small hemorrhages may be overlooked without adequate lighting.
Cannot alone diagnose systemic disease; must consider clinical context.
Differentiation between trauma and systemic cause may require history, labs, or imaging.

Patient counseling

Explain the likely cause of the hemorrhage (trauma vs. systemic).
Advise protection of nails from further injury.
Recommend medical evaluation if multiple nails are involved or systemic symptoms are present.

Conclusion

Subungual hemorrhage is a clinical sign of capillary damage under the nail, which may result from trauma, infection, or systemic illness. Recognition of splinter hemorrhages can provide early clues to subacute bacterial endocarditis or other systemic conditions, guiding further evaluation and management.

References

Habib G, Lancellotti P, Antunes MJ, et al. 2015 ESC Guidelines for the management of infective endocarditis. Eur Heart J. 2015;36(44):3075–3128.
Scher RK, Daniel CR. Nail Disorders: Diagnosis and Management. Philadelphia: Saunders Elsevier; 2005.
Tosti A, et al. Disorders of the Nails: A Clinical Guide. 2nd ed. Boca Raton: CRC Press; 2016.
Lyon VB, et al. Splinter hemorrhages in systemic disease. Am J Med. 1987;83(6):1017–1022.