Examining the Fingernails When Evaluating Presenting Symptoms in Elderly Patients

Observing Nail Color

Abnormalities of the Lunula

If the lunula is absent, consider anemia or malnutrition (Figure 16). A pyramidal lunula might indicate excessive manicure or trauma (Figure 17). A pale blue lunula suggests diabetes mellitus. If the lunula has red discoloration, consider the following causes among others (Figure 18):

• Cardiovascular disease;
  
  
• Collagen vascular disease; and
  
  
• Hematologic malignancy.

Figure 16. Absent lunula.

Figure 17. Pyramidal lunula.

Figure 18. Lunula with red discoloration.

Transverse White Lines (Mee's lines)

Any acute illness can produce transverse milky white lines. In addition, they might be caused by heavy metal toxicity (classically arsenic) or chemotherapy. The time of event may be determined from the location of the lines on nail (Figure 19).

Figure 19. Note the Mee's line approximately one third of the way up the nail, suggesting a significant illness 2 months previously.

Leukonychia Striae

Leukonychia striae are white splotches caused by minor trauma to the nail matrix (Figure 20). The timing can be determined by the location of the splotches on the nail.

Figure 20. Example of leukonychia striae. Note location of white splotches, which can indicate timing of the traumatic event.

Longitudinal Brown Lines

Longitudinal brown lines form because of increased melanin produced by nail matrix melanocytes (Figure 21). They are associated with:

• Addison's disease;
  
  
• Nevus at the nail base;
  
  
• Breast cancer;
  
  
• Melanoma (check for periungal pigmentation); and
  
  
• Trauma.

Figure 21. Longitudinal brown lines.

Splinter Hemorrhages

Splinter hemorrhages are caused by hemorrhage of the distal capillary loop (Figure 22). Note the thickness of these areas. They are associated with the following:

• Subacute bacterial endocarditis;
  
  
• Systemic lupus erythematosus;
  
  
• Trichinosis;
  
  
• Pityriasis rubra pilaris;
  
  
• Psoriasis; and
  
  
• Renal failure.

Figure 22. Splinter hemorrhages tend to be fat.

Terry's Half and Half Nails

With Terry's half and half nails, the proximal portion is white (edema and anemia) and the distal portion is dark. These nails imply either renal or liver disease (Figures 23A, 23B).

Figure 23A. This example of Terry's half and half nails suggests liver disease (no brown lines).

Figure 23B. Half and half nails imply renal disease when there is a brown band at the junction of the erythema and the free edge. Image courtesy of www.dermnet.com Used with permission.