High prevalence of Demodex in eyelashes with cylindrical dandruff.
OBJECTIVE
To determine the prevalence of Demodex in eyelashes with cylindrical dandruff (CD).


METHODS
A modified sampling and counting method was applied to 55 clinical cases. Patients were divided in to group A (n = 20) with diffuse CD, group B (n = 12) with sporadic CD, and group C (n = 23) with clean lashes or greasy scales, of which the latter was divided into subgroup C1 (n = 15) without lid hygiene and subgroup C2 (n = 8) using daily lid hygiene for the past year. Each patient underwent a routine complete eye examination and modified counts of Demodex.


RESULTS
Demodex was found in all group A and B patients (n = 32) with CD, which was significantly higher than the 22% of group C patients (n = 23) without CD (P < 0.001). The Demodex counts were 4.1 +/- 1.0 and 2.0 +/- 1.2 per epilated lash with retained CD, significantly higher than the 0.2 +/- 0.5 and 0.2 +/- 0.4 per lash without retained CD in groups A and B, respectively (each P < 0.001) and than the 0.01 +/- 0.09 and 0.12 +/- 0.41 per lash in subgroups C1 and C2, respectively (each P < 0.001). Demodex was still found in CD fragments left on the lid skin after epilation. Five Demodex brevis mites were found among the 422 Demodex specimens.


CONCLUSIONS
The modified sampling and counting method showed that the prior controversy regarding Demodex has resulted from miscounting and confirmed that lashes with CD are pathognomonic for ocular Demodex infestation. Lid hygiene with shampoo reduces Demodex counts but does not eradicate the mites.
Gao
Ying-Ying
YY
Ocular Surface Center and Ocular Surface Research & Education Foundation, 7000 SW 97 Avenue, Miami, FL 33173, USA.
Di Pascuale
Mario A
MA
Li
Wei
W
Liu
Daniel Tzong-Shyue
DT
Baradaran-Rafii
Alireza
A
Elizondo
Antonio
A
Kawakita
Tetsuya
T
Raju
Vadrevu K
VK
Tseng
Scheffer C G
SC
D000328:Adult; D000818:Animals; D015822:Eye Infections, Parasitic / Q000453:epidemiology*; D005140:Eyelashes / Q000469:parasitology*; D006197:Hair / Q000469:parasitology; D006201:Hair Diseases / Q000453:epidemiology*; D006204:Hair Removal; D006801:Humans; D008875:Middle Aged; D008924:Mite Infestations / Q000453:epidemiology*; D008925:Mites; D015995:Prevalence; D012871:Skin Diseases / Q000453:epidemiology*