Pili bifurcati L67

Giovannini 1893, Weary et al. 1973

Rare clinical picture in which bifurcations of the hair shaft can be detected by light microscopy. Parallel branches are formed.

Prevalence is not known; only a few cases have been described so far.

The cause of pili bifurcati is a temporary duplication of the papilla tip during the anagen phase, temporarily forming two complete shafts in the same follicular matrix. These emerge through a single hair channel. When both papilla tips merge again, the parallel branches reunite to form a single shaft. Repeated duplications of the optic disc tip during the anagen phase may result in a series of circumscribed bifurcations along the shaft. This finding is called "Pili multi-bifurcati".

Clinically, the affected patients are characterized by focal or diffuse alopecia reminiscent of trichotillomania or pili torti.

Pili bifurcati can occur in normal hair, in Pili canaliculi or in Monilethrix (see there).

Pili bifurcati have been found in mosaic trisomy 8 syndrome, in Pseudo-Monilethrix and in protein deficiency conditions.

Furthermore, the occurrence of pili bifurcati in ulcerative colitis and extensive bowel resection has been reported.

There is no specific therapy.

Under a therapy with minoxidil improvements have been described (Singh G et al. 2016). A change in diet towards a protein-rich diet is recommended.

Damaging mechanical and/or thermal hair procedures for hair care should be avoided.

1. Camacho F, Jorquera E (1995) Pili bifurcati. Eur J Dermatol 5: 88-89
2. Camacho FM, Happle R, Tosti A, Whiting D (2000) The different faces of pili bifurcati. A review. Eur J Dermatol 10: 337-340
3. Singh G et al (2016) Prognosis and Management of Congenital Hair Shaft Disorders withoutFragility-Part
   II. Pediatric Dermatol 33:481-487.
4. Weary PE, Hendricks AA, Warner Ajgaonkar G (1973) Pili bifurcati: New anomaly growth. Arch Dermatol 108: 403-407