Demodex folliculorum and Demodex brevis as a cause of chronic marginal blepharitis.
BACKGROUND
Intensive long-term studies of Demodex spp. (D.) and its role in chronic blepharits have been carried out in recent years by scientists from the Pomeranian Medical University in Szczecin. It has resulted in numerous publications, spurring a lot of interest worldwide. A few of the papers have been cited in leading American medical journals. In recent years many papers dealing with demodicosis of the eyelids have been published worldwide. Based on the growing interest in the role of Demodex spp. in chronic blepharitis we decided to present and discuss the results of the latest experimental and clinical studies.


METHODS
A review of the literature concerning the role of D. folliculorum and D. brevis in the pathogenesis of chronic blepharitis was done.


RESULTS
Demodex spp. are intradermal parasites, which thrive in follicles and sebaceous glands of humans and animals. D. is spread by direct contact and probably by dust containing eggs (figs. 1, 2, 3). Currently, it is thought that pathological changes in the course of demodicosis of the eyelids are consequences of: (1) blockage of follicles and leading out tubules of sebaceous glands by the mites and by reactive hyperkeratinization and epithelial hyperplasia; (2) a mechanical vector role of bacteria; (3) host's inflammatory reaction to the presence of parasite's chitine as a foreign body; and (4) stimulation of the host's humoral responses and cell-mediated immunological reactions under the influence of the mites and their waste products. It has been established that: (1) D. folliculorum and D. brevis are cosmopolitan in terms of their distribution; (2) Infection of Demodex spp. often occurs in the course of chronic blepharitis; (3) With the increase in age, the prevalence rate of eyelid demodicosis rises; (4) Demodicosis of the eyelids may be the effect of the decrease of immunity of some patients. Treatment of demodicosis of the eyelids as a general rule lasts a few months. The use of yellow mercurial ointment, sulphur ointment, camphorated oil, crotamiton, choline esterase inhibitors, sulfacetamide, steroids, antibiotics, as well as antimycotic drugs offers some improvement. A good response has been observed after oral application of ivermectin along with topical application of cream permethrin. However, the best results were obtained after 2% metronidazole gel or ointment treatment. Medical University in Szczecin. It has resulted in numerous publications, spurring a lot of interest worldwide. A few of the papers have been cited in leading American medical journals. In recent years many papers dealing with demodicosis of the eyelids have been published worldwide. Based on the growing interest in the role ofDemodex spp. in chronic blepharitis we decided to present and discuss the results of the latest experimental and clinical studies. Material and methods: A review of the literature concerning the role of D. folliculorum and D. brevis in the pathogenesis of chronic blepharitis was done. Results: Demodex spp. are intradermal parasites, which thrive in follicles and sebaceous glands of humans and animals. D. is spread by direct contact and probably by dust containing eggs (figs. 1, 2, 3). Currently, it is thought that pathological changes in the course of demodicosis of the eyelids are consequences of: (1) blockage of follicles and leading out tubules of sebaceous glands by the mites and by reactive hyperkeratinization and epithelial hyperplasia; (2) a mechanical vector role of bacteria; (3) host's inflammatory reaction to the presence of parasite's chitine as a foreign body; and (4) stimulation of the host's humoral responses and cell-mediated immunological reactions under the influence of the mites and their waste products. It has been established that: (1) D. folliculorum and D. brevis are cosmopolitan in terms of their distribution; (2) Infection ofDemodex spp. often occurs in the course of chronic blepharitis; (3) With the increase in age, the prevalence rate of eyelid demodicosis rises; (4) Demodicosis of the eyelids may be the effect of the decrease of immunity of some patients. Treatment of demodicosis of the eyelids as a general rule lasts a few months. The use of yellow mercurial ointment, sulphur ointment, camphorated oil, crotamiton, choline esterase inhibitors, sulfacetamide, steroids, antibiotics, as well as antimycotic drugs offers some improvement. A good response has been observed after oral application of ivermectin along with topical application of cream permethrin. However, the best results were obtained after 2% metronidazole gel or ointment treatment.
Katedra i Klinika Okulistyki Pomorskiej Akademii Medycznej w Szczecinie al. Powstańców Wlkp. 72, 70-111 Szczecin.
Damian
D
Czepita
Wanda
W
Kuźna-Grygiel
Maciej
M
Czepita
Andrzej
A
Grobelny
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000818:Animals; D000977:Antiparasitic Agents / Q000627:therapeutic use; D001762:Blepharitis / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology / Q000469:parasitology*; D002648:Child; D002908:Chronic Disease; D005260:Female; D006790:Host-Parasite Interactions; D006801:Humans; D015994:Incidence; D007559:Ivermectin / Q000627:therapeutic use; D008018:Life Cycle Stages; D008297:Male; D008924:Mite Infestations / Q000188:drug therapy / Q000453:epidemiology / Q000469:parasitology; D008925:Mites / Q000145:classification* / Q000502:physiology; D011044:Poland / Q000453:epidemiology; D017678:Sex Distribution; D013045:Species Specificity
D000977:Antiparasitic Agents; D007559:Ivermectin