Table 2

Stains characteristics in cases

Stains characteristicsCases N (%)*
Time of stain appearance (years)
 1–415 (31)
 5–92 (4)
 ≥1031 (65)
Suffering due to the stain3 (6)
Physical/chemical attempt to remove the stain23 (48)
Variation over time (stain size or intensity)18 (37)
Median (IQR) stains per cases3 (2–4)
 Nails stained2 (1–3)
 Stains on skin1 (0–2)
Median (IQR) number of fingers discoloured per case3 (2–4)
 First finger25 (52)
 Second finger45 (94)
 Third finger37 (77)
 Fourth finger1 (2)
 Fifth finger0 (0)
Median (IQR) total skin area stained per case (square centimetre)1.9 (1.0–3.1)
  • Values are numbers of cases (percentage) unless stated otherwise.

  • IQR 25–75%.

  • *Stain location, size and colour intensity were impossible to determine for one patient due to peripheral cyanosis at the time of examination. In another three cases, the precise size of stains present on the skin (five stains) was not measured because of scant demarcation of the stain.