I think my children breathed a huge sigh of relief when they all eventually went somewhere else to get their hair cut. I can’t say I particularly enjoyed the experience either; not only was there the stress of getting things even and balanced on either side of the head but there was always the worry that something fleshier than hair might be inadvertently snipped off.
And what has this got to do with dermatology? Well, there was an interesting case report in the March/April 2018 edition of Pediatric Dermatology on a skin condition caused by a home haircut.
[Winkler A, Prendaville B, Wiss K. Curvilinear, erythematous plantar patch in a toddler. Pediatr Dermatol 2018; 35(2):251-2.]
Well, it wasn’t the home haircut that specifically caused the skin problem. It was more the fact that the child had walked barefoot through the pile of freshly cut hair from his most recent hair cut shortly before the skin problem started.
And what happened?
The child presented to dermatology with a 4-day history of a painful red line on the sole of his foot. The mother noticed that the curved red line moved towards his toes over the subsequent days.
There was no problem with the rest of his skin, no family history of skin problems and there was no history of recent travel outside the state nor exposure to sand or soil.
What was the cause of the red line?
A dark line could be seen within the painful red line, consistent with a hair. However, as the child was only 2 years old, the dark line could not be extracted. A high percentage urea cream was applied to the affected area for a week and when the hair became more superficial it was extracted easily with immediate improvement.
As with many dermatological conditions, it has a more complicated sounding name – cutaneous pili migrans.
Is it common?
It actually is rather uncommon. Most of the cases reported in the literature are from South East Asia. It is thought that the high tensile strength of Asian hair allows the hair to penetrate the skin layers with friction.
[Khare S, Sengar SS. Cutaneous pili migrans: A creeping eruption like condition easy to diagnose and cure. Med J Arm Forces India 2016;72:94-101.]
[Kim YH, Kim, JI, Hwang SH. Cutaneous Pili Migrans. Ann Dermatol 2014;26:534-5.]
Should we be worried?
As dermatologists, we worry when we see linear red lines on the soles of the feet that it is due to a condition called cutaneous larva migrans or creeping itch or eruption. This is caused by hookworm larvae penetrating the skin. There is often a history of walking barefoot on sand infested with the larvae, generally due to contamination with animal faeces. Beaches at high risk of infestation of hookworm larvae are mainly in central and south America. The red line on the sole of the foot moves as the larva migrates under the skin layers and is usually intensely itchy.
How can you tell the difference?
Apparently, cutaneous pili migrans tends to move in a linear fashion in one direction only whereas cutaneous larva migrans can move in any direction and the tracts are more serpiginous.
Also, the lesions in cutaneous pili migrans tend to either cause no problems or may be painful whereas in cutaneous larva migrans the lesions are extremely itchy.
The diagnosis is made on the history and close inspection of the lesion and removal of the hair is simple enough.
So if you’re still in that era of child rearing where the home hair cut is necessary, just make sure you don’t walk barefoot through the hairs after!
Dr Sandy Flann, Consultant dermatologist.