Nail-Bed Splinter Hemorrhage Workup
Splinter hemorrhage is diagnosed clinically as nonblanchable, narrow, longitudinal red to reddish-brown hemorrhage lines under the nail plate. [1] Most distal splinter hemorrhages are caused by nail-bed trauma. [2] Workup should focus on excluding infectious endocarditis and systemic disease when the pattern, location, or associated symptoms increase concern. [3]
Immediate Clinical Assessment
History should assess recent nail trauma or repeated microtrauma (including occupational or behavioral causes). [2] Physical examination should document laterality, number of nails involved, and proximal versus distal location on the nail bed. [4] Additional assessment should screen for systemic symptoms that increase suspicion for infective endocarditis (eg, fever or constitutional symptoms) and other peripheral stigmata. [3]
Benign Trauma-Pattern Splinter Hemorrhage
If the hemorrhage is distal and corresponds with recent or plausible trauma, no extensive diagnostic testing is typically required. [2] Observation is appropriate when there are no systemic features and the lesion behaves as an isolated post-traumatic finding. [5]
Infective Endocarditis–Oriented Workup
Splinter hemorrhages are recognized as peripheral stigmata of infective endocarditis. [3] Further evaluation for endocarditis should be pursued when clinical suspicion is moderate or high or when splinter hemorrhages fit a higher-risk pattern. [3]
Endocarditis laboratory evaluation and blood culture strategy
Blood cultures should be obtained before starting antibiotics when infective endocarditis is suspected. [3] Common blood work in suspected endocarditis includes CBC with differential and inflammatory markers such as ESR and CRP. [6]
Cardiac imaging
Echocardiography should be performed to identify valvular abnormalities in patients with moderate or high suspicion of infective endocarditis. [7]
Systemic Disease Evaluation Outside Endocarditis
Splinter hemorrhages can be associated with psoriasis. [9] Splinter hemorrhages can also be associated with renal, pulmonary, and endocrine diseases. [9] Splinter hemorrhages are also reported in systemic hematologic conditions and systemic inflammatory disorders, so associated symptoms should be reviewed to guide targeted testing. [9]
Medication- and Coagulopathy-Related Evaluation
Medication use that impairs vascular integrity or platelet function can be associated with splinter hemorrhages. [5] Bleeding diathesis risk should be assessed through history of easy bruising, prior bleeding, and anticoagulant or antiplatelet exposure. [5]
When Diagnostic Testing Is Most Likely to Change Management
Endocarditis-directed testing is most warranted when any of the following are present: systemic symptoms compatible with infection, significant cardiac risk factors, or other peripheral stigmata in the same clinical context. [3] Targeted systemic evaluation is most warranted when splinter hemorrhages are multiple, persistent, or not attributable to trauma. [9]
Common Pitfalls to Avoid
Splinter hemorrhages are not pathognomonic for any single disease, so attribution to trauma should be avoided when the distribution or clinical context is atypical. [9] Overtesting for isolated distal post-traumatic hemorrhage should be avoided when there are no concerning associated findings. [2]