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Chioveanu FG, Niculet E, Torlac C, Busila C, Tatu AL. Beyond the Surface: Understanding Demodex and Its Link to Blepharitis and Facial Dermatoses. Clin Ophthalmol 2024; 18:1801-1810. [PMID: 38948346 PMCID: PMC11213710 DOI: 10.2147/opth.s440199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Accepted: 04/29/2024] [Indexed: 07/02/2024] Open
Abstract
Demodex represents the most frequent ectoparasite found in humans. Although Demodex mites are considered commensals of human pilosebaceous units, an abnormally high mite density can cause several ocular and cutaneous symptoms and signs, sometimes to a severe degree. Both Demodex spp. (folliculorum and brevis) play a significant part in eye pathology and facial dermatoses. These mites have been related to blepharitis, ocular rosacea, meibomian gland dysfunction and various skin diseases, including rosacea, demodicosis and seborrheic dermatitis. Understanding the importance of Demodex in both eye and skin conditions is crucial for accurate diagnosis and appropriate management strategies, which may involve targeted treatments to control the mite population and reduce associated symptoms.
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Affiliation(s)
- Flavia Giorgiana Chioveanu
- Hexamed” Ophthalmology Clinic, Braila, Romania
- Biomedical Doctoral School, “Dunarea de Jos” University, Galati, Romania
| | - Elena Niculet
- Department of Morphological and Functional Sciences, Faculty of Medicine and Pharmacy, “Dunarea de Jos” University, Galaţi, Romania
- Multidisciplinary Integrated Center of Dermatological Interface Research MIC-DIR, “Dunarea de Jos” University, Galaţi, Romania
| | - Cristina Torlac
- Biomedical Doctoral School, “Dunarea de Jos” University, Galati, Romania
- Individual Medical Office - Dentistry, Galati, Romania
| | - Camelia Busila
- Dunarea de Jos University of Galati, Faculty of Medicine and Pharmacy, Galati, Romania
- Sf. Ioan Emergency Clinical Paediatric Hospital, Galati, Romania
| | - Alin Laurentiu Tatu
- Multidisciplinary Integrated Center of Dermatological Interface Research MIC-DIR, “Dunarea de Jos” University, Galaţi, Romania
- Clinical Medical Department, Faculty of Medicine and Pharmacy, “Dunarea de Jos” University, Galaţi, Romania
- Dermatology Department, “Sf. Cuvioasa Parascheva” Clinical Hospital of Infectious Diseases, Galaţi, Romania
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Udomwech L, Tawanwongsri W, Mordmuang A. Chicago sky blue gel for better visualization of Demodex in patients with Demodex blepharitis. PeerJ 2023; 11:e16378. [PMID: 38025681 PMCID: PMC10658889 DOI: 10.7717/peerj.16378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
Background Demodex blepharitis is a common chronic disease. The number of mites is associated with ocular discomfort. The accurate number derived from well-stained specimens is, hence, in favor of diagnosing, monitoring, and determining treatment responses. Methods A cross-sectional study was conducted between April and July 2022 at the dermatology and ophthalmology clinic, Walailak University, Thailand. Adult participants with clinical suspicion of Demodex blepharitis were recruited. We examined eyelashes under light microscopy to quantify the number of Demodex mites before and after adding CSB gel. The mite counts, evaluated by an untrained investigator and an experienced investigator, were recorded and compared. Results A total of 30 participants were included for final analysis, among which 25 (83.3%) were female. The median age was 64.0 years (IQR, 61.0-68.0). The median Demodex counts evaluated by the experienced investigator before and after adding CSB gel were 1.0 (IQR, 0.0-1.0) and 2.5 (IQR, 2.0-3.0), respectively (p < 0.001). Moreover, the median Demodex counts evaluated by the untrained investigator before and after adding CSB gel were 1.0 (IQR, 0.0-1.0) and 2.0 (IQR, 1.0-3.0), respectively (p < 0.001). The correlation coefficient between Demodex counts after the addition of CSB counted by the experienced investigator and those counted by the untrained investigator was 0.92 (p < 0.001). CSB gel is a promising product to identify and quantify the number of Demodex mites. The findings supported the consideration of CSB gel as one of the diagnostic stains.
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Affiliation(s)
- Lunla Udomwech
- Department of Ophthalmology, School of Medicine, Walailak University, Thasala, Nakhon Si Thammarat, Thailand
| | - Weeratian Tawanwongsri
- Division of Dermatology, Department of Internal Medicine, School of Medicine, Walailak University, Thasala, Nakhon Si Thammarat, Thailand
| | - Auemphon Mordmuang
- Department of Microbiology, School of Medicine, Walailak University, Thasala, Nakhon Si Thammarat, Thailand
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Chudzicka-Strugała I, Gołębiewska I, Brudecki G, Elamin W, Zwoździak B. Demodicosis in Different Age Groups and Alternative Treatment Options-A Review. J Clin Med 2023; 12:jcm12041649. [PMID: 36836184 PMCID: PMC9961532 DOI: 10.3390/jcm12041649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 01/26/2023] [Accepted: 02/01/2023] [Indexed: 02/22/2023] Open
Abstract
Infestation with Demodex mites is a common occurrence, especially in adults and the elderly. More recent attention has been paid to the presence of Demodex spp. mites in children, even ones without comorbidities. It causes both dermatological and ophthalmological problems. The presence of Demodex spp. is often asymptomatic, thus it is suggested to include parasitological investigation tests in dermatological diagnostics, in addition to bacteriological analysis. Literature reports show that Demodex spp. are related to the pathogenesis of numerous dermatoses, including rosacea or demodicosis gravis, and common eye pathologies reported by patients such as dry eye syndrome or ocular surface inflammatory conditions, such as blepharitis, chalazia, Meibomian gland dysfunction, and keratitis. Treatment of patients is a challenge and is usually prolonged, therefore it is important to carefully diagnose and properly select the therapy regimen for the treatment to be successful, and with minimal side effects, especially for young patients. Apart from the use of essential oils, research is ongoing for new alternative preparations active against Demodex sp. Our review was focused on the analysis of the current literature data on the available agents in the treatment of demodicosis in adults and children.
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Affiliation(s)
- Izabela Chudzicka-Strugała
- Department of Medical Microbiology, Poznan University of Medical Sciences, Rokietnicka 10, 60-806 Poznan, Poland
| | - Iwona Gołębiewska
- Earth and Life Institute (ELI), Université Catholique de Louvain, Croix du Sud 2, 1348 Louvain-La-Neuve, Belgium
- Correspondence:
| | - Grzegorz Brudecki
- Group 42 (Healthcare), Masdar City, Abu Dhabi P.O. Box 112778, United Arab Emirates
| | - Wael Elamin
- Group 42 (Healthcare), Masdar City, Abu Dhabi P.O. Box 112778, United Arab Emirates
| | - Barbara Zwoździak
- Department of Medical Microbiology, Poznan University of Medical Sciences, Rokietnicka 10, 60-806 Poznan, Poland
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Serarslan G, Makbule Kaya Ö, Dirican E. Scale and Pustule on Dermoscopy of Rosacea: A Diagnostic Clue for Demodex Species. Dermatol Pract Concept 2021; 11:e2021139. [PMID: 33614217 DOI: 10.5826/dpc.1101a139] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2020] [Indexed: 01/17/2023] Open
Abstract
Background Demodex mites are highly found in the skin of patients with rosacea. The diagnosis of Demodex can be made by standardized skin surface biopsy. Dermoscopy is a tool used in the noninvasive diagnosis of various dermatological diseases. Objectives To determine whether dermoscopic features of demodicosis are associated with the result of standardized skin surface biopsy in patients with rosacea and to compare dermoscopic features of rosacea in Demodex-positive and negative samples and Demodex type. Methods A total of 30 patients (7 male, 23 female) were included in the study. Dermoscopic examination was performed on both the clinically most severely affected areas and adjacent healthy skin. The skin surface biopsy sample was taken from the same place from where the dermoscopic image was taken. Results A total of 83 (lesion n = 60, non-lesion n = 23) areas were evaluated. Demodex was detected in 60.2% (n = 50) of the samples. Half of these samples revealed only Demodex folliculorum, and the remaining half revealed D folliculorum and Demodex brevis. Of the Demodex-positive samples, 88% had Demodex tails (P =0.001) and 68% Demodex follicular openings (P = 0.002) on dermoscopy. In D folliculorum+D brevis-positive samples, the rate of scale and pustule was higher than D folliculorum-positive samples (P = 0.017 and P = 0032, respectively). Conclusions The sensitivity and specificity of Demodex tail are higher than Demodex follicular opening and scale and pustule detection with dermoscopy and may indicate the coexistence of both D folliculorum and D brevis.
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Affiliation(s)
- Gamze Serarslan
- Department of Dermatology, Mustafa Kemal University, Hatay, Turkey
| | | | - Emre Dirican
- Department of Biostatistics, Mustafa Kemal University Hatay, Turkey
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Zhang AC, Muntz A, Wang MTM, Craig JP, Downie LE. Ocular Demodex: a systematic review of the clinical literature. Ophthalmic Physiol Opt 2020; 40:389-432. [PMID: 32691894 DOI: 10.1111/opo.12691] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 04/06/2020] [Accepted: 04/14/2020] [Indexed: 12/11/2022]
Abstract
PURPOSE There is increasing clinical and research interest in the potential contribution of Demodex to ocular surface disease. The aim of this systematic review was to summarise and synthesise current clinical evidence relating to the aetiology, diagnosis and treatment of ocular Demodex. RECENT FINDINGS A comprehensive literature search was performed in OVID Medline, OVID Embase, and clinical trial registries, for studies published between 1990 and August 2019, examining Demodex on the ocular surface. The review included primary clinical research studies and systematic reviews of primary clinical research studies, where Demodex was considered in the context of the ocular surface and/or adnexa. Studies were categorised using the National Health and Medical Research Council evidence hierarchy. Risk of bias assessment was performed using validated tools for studies categorised as providing Level I or II evidence. A total of 87 studies were eligible for inclusion, including two systematic reviews. Most studies (60%) were observational, describing the prevalence of ocular Demodex in different clinical populations. There was a high degree of variability in the epidemiological data derived from cross-sectional aetiology studies. There was mostly consistent evidence to support an association between ocular Demodex and chronic blepharitis. Seven diagnostic test-accuracy studies were identified, which considered a range of techniques, including slit lamp examination for cylindrical eyelash collarettes and/or eyelash manipulation techniques, light microscopic evaluation of epilated eyelashes and in vivo confocal microscopy. There is currently no accepted gold-standard diagnostic method for ocular Demodex. For intervention studies, there was one systematic review, 11 published randomised trials, six trial registry entries, and nine case series. Despite a number of recent trials, the appropriate treatment regimen for ocular Demodex (including the optimal criteria and timing of an intervention) is not clearly established. CONCLUSIONS This comprehensive narrative synthesis has captured the landscape of clinical evidence relating to the prevalence, aetiology, diagnosis and treatment of ocular Demodex. There remain opportunities to enhance understanding of its role in ocular surface disease, best diagnostic approaches and optimal treatment protocols.
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Affiliation(s)
- Alexis Ceecee Zhang
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Alex Muntz
- Department of Ophthalmology, New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand
| | - Michael T M Wang
- Department of Ophthalmology, New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand
| | - Jennifer P Craig
- Department of Ophthalmology, New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand
| | - Laura E Downie
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
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Lacey N, Russell-Hallinan A, Zouboulis CC, Powell FC. Demodex mites modulate sebocyte immune reaction: possible role in the pathogenesis of rosacea. Br J Dermatol 2018. [PMID: 29532463 DOI: 10.1111/bjd.16540] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Rosacea is a common facial skin disorder mainly affecting middle-aged adults. Its aetiology is unknown and pathogenesis uncertain. Activation of the host innate immune response has been identified as an important factor. The Demodex mite population in the skin of rosacea patients is significantly higher than in patients with normal skin, suggesting that they may be of aetiological importance in this disorder. OBJECTIVES To determine the potential of Demodex mites to interact with the host immune system. METHODS Live Demodex mites were extracted from normal facial skin of control subjects and used in cell stimulation experiments with the immortalized SZ95 sebocyte line. Time- and mite-dose-dependent experiments were performed. Direct effects of Demodex and effects of the medium in which Demodex had been cultured were evaluated on the Toll-like receptor (TLR) signalling pathway on both a gene and protein expression level. RESULTS Mites modulated TLR signalling events on both mRNA and protein levels in SZ95 sebocytes. An initial trend towards downmodulation of genes in this pathway was observed. A subsequent switch to positive gene upregulation was recorded after 48 h of coculture. Demodex secreted bioactive molecules that affected TLR2 receptor expression by sebocytes. High numbers of Demodex induced proinflammatory cytokine secretion, whereas lower numbers did not. CONCLUSIONS Demodex mites have the capacity to modulate the TLR signalling pathway of an immortalized human sebocyte line. Mites have the capacity to secrete bioactive molecules that affect the immune reactivity of sebocytes. Increasing mite numbers influenced interleukin-8 secretion by these cells.
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Affiliation(s)
- N Lacey
- The Charles Institute of Dermatology, University College Dublin, Belfield, Dublin 4, Ireland
| | - A Russell-Hallinan
- The Charles Institute of Dermatology, University College Dublin, Belfield, Dublin 4, Ireland
| | - C C Zouboulis
- Departments of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane, Dessau, Germany
| | - F C Powell
- The Charles Institute of Dermatology, University College Dublin, Belfield, Dublin 4, Ireland
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Murillo N, Raoult D. Skin microbiota: overview and role in the skin diseases acne vulgaris and rosacea. Future Microbiol 2013; 8:209-22. [PMID: 23374126 DOI: 10.2217/fmb.12.141] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
As the first barrier to environmental exposures, human skin has developed an integrated immune system to protect the inner body from chemical, physical or microbial insults. Microorganisms inhabiting superficial skin layers are known as skin microbiota and include bacteria, viruses, archaea and fungi. The microbiota composition is crucial in the instruction and support of the skin's immune system. Changes in microbiota can be due to individual, environmental or behavioral factors, such as age, climate, hygiene or antibiotic consumption, which can cause dysbiosis. The contribution of skin microbiota to disease development is known in atopic dermatitis, where there is an increase in Staphylococcus aureus. Culture-independent studies have enabled more accurate descriptions of this complex interplay. Microbial imbalance is associated with the development of various diseases. This review focuses on microbial imbalances in acne vulgaris and rosacea.
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Affiliation(s)
- Nathalia Murillo
- Université Aix Marseille, URMITE, UMR CNRS 7278, IRD 198, INSERM 1095, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
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Kaya S, Selimoglu MA, Kaya OA, Ozgen U. Prevalence of Demodex folliculorum and Demodex brevis in childhood malnutrition and malignancy. Pediatr Int 2013; 55:85-9. [PMID: 23039878 DOI: 10.1111/j.1442-200x.2012.03740.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 09/05/2012] [Indexed: 12/01/2022]
Abstract
BACKGROUND Hair follicle mites, Demodex folliculorum and Demodex brevis, are known to accompany immune-deficiency states, however no study so far has investigated their presence in malnutrition. In this study we aimed to determine the prevalence of those mites in childhood malnutrition, malignancy and risk factors. METHODS One hundred children with malnutrition, 31 children with malignancy and 63 children without any chronic disease and infection were included in this study. History, physical examination, anthropometric measurements and routine laboratory findings were recorded. Demodex spp. were investigated by standard superficial skin biopsies. RESULTS Demodex was found in 25 patients (25%), 10 patients (32.3%), and one patient (1.6%) among malnutrition, malignancy, and control groups, respectively (P = 0.001). By using multilogistic regression binary method, it was found that malnutrition, malignancy and low socioeconomic level increased the risk 17.37 times (P = 0.006), 27.29 times (P = 0.002), and 2.3 times (P = 0.037), respectively. Of 22 children who were evaluated after 6 months, 13 (59.1%) were negative for Demodex. In 11 (84.6%) of those 13, nutritional status was improved. CONCLUSION Demodex was detected in approximately in one-quarter and one-third of children with malnutrition and malignancy, respectively. Eliminating the cause of immunosuppression, such as poor nutritional status, seems also to be an effective method for eliminating Demodex.
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Affiliation(s)
- Sadik Kaya
- Department of Pediatrics, Faculty of Medicine, Inönü University, Malatya, Turkey
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Jarmuda S, O'Reilly N, Żaba R, Jakubowicz O, Szkaradkiewicz A, Kavanagh K. Potential role of Demodex mites and bacteria in the induction of rosacea. J Med Microbiol 2012; 61:1504-1510. [PMID: 22933353 DOI: 10.1099/jmm.0.048090-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Rosacea is a common dermatological condition that predominantly affects the central regions of the face. Rosacea affects up to 3 % of the world's population and a number of subtypes are recognized. Rosacea can be treated with a variety of antibiotics (e.g. tetracycline or metronidazole) yet no role for bacteria or microbes in its aetiology has been conclusively established. The density of Demodex mites in the skin of rosacea patients is higher than in controls, suggesting a possible role for these mites in the induction of this condition. In addition, Bacillus oleronius, known to be sensitive to the antibiotics used to treat rosacea, has been isolated from a Demodex mite from a patient with papulopustular rosacea and a potential role for this bacterium in the induction of rosacea has been proposed. Staphylococcus epidermidis has been isolated predominantly from the pustules of rosacea patients but not from unaffected skin and may be transported around the face by Demodex mites. These findings raise the possibility that rosacea is fundamentally a bacterial disease resulting from the over-proliferation of Demodex mites living in skin damaged as a result of adverse weathering, age or the production of sebum with an altered fatty acid content. This review surveys the literature relating to the role of Demodex mites and their associated bacteria in the induction and persistence of rosacea and highlights possible therapeutic options.
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Affiliation(s)
- Stanisław Jarmuda
- Department and Clinic of Dermatology, University of Medical Sciences, Poznań, Poland
| | - Niamh O'Reilly
- Department of Biology, National University of Ireland Maynooth, Co. Kildare, Ireland
| | - Ryszard Żaba
- Department and Clinic of Dermatology, University of Medical Sciences, Poznań, Poland
| | - Oliwia Jakubowicz
- Department and Clinic of Dermatology, University of Medical Sciences, Poznań, Poland
| | | | - Kevin Kavanagh
- Department of Biology, National University of Ireland Maynooth, Co. Kildare, Ireland
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Silveira R, Ribeiro R, Cruz A, Almeida L, Carvalho E. Demodicose suína no norte do estado do Rio de Janeiro: relato de caso. ARQ BRAS MED VET ZOO 2012. [DOI: 10.1590/s0102-09352012000300005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Um leitão oriundo de um criatório do norte do estado do Rio de Janeiro, mantido no biotério do Hospital Veterinário da Universidade Estadual do Norte Fluminense Darcy Ribeiro e utilizado como caso piloto de projeto de pesquisa para investigações sobre o acesso videolaparoscópico retal (NOTES - Natural Orifice Translumenal Endoscopic Surgery), foi eutanasiado e necropsiado. Amostras do ponto de acesso do tubo de inserção na região mucocutânea anal foram colhidas, fixadas em formalina neutra tamponada a 10%, processadas por inclusão em parafina e coradas pela hematoxilina e eosina para histologia. Observou-se o comprometimento de folículos que, dilatados, exibiam formações que lembravam Demodex spp. cortados em vários sentidos e, por se tratar de ácaros espécie-específicos, concluiu-se como D. phylloides. Na citopatologia, o ácaro foi recuperado e identificado a fresco, mostrando-se alongado, com quatro pares de patas ventrais e no terço anterior do corpo. Este se refere ao primeiro registro de demodicose suína no estado do Rio de Janeiro.
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Using environmental scanning electron microscopy (ESEM) as a quantitative method to analyse the attachment of Giardia duodenalis to epithelial cells. Micron 2012; 43:494-6. [DOI: 10.1016/j.micron.2011.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 08/15/2011] [Indexed: 11/20/2022]
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Forton F. Papulopustular rosacea, skin immunity and Demodex: pityriasis folliculorum as a missing link. J Eur Acad Dermatol Venereol 2011; 26:19-28. [DOI: 10.1111/j.1468-3083.2011.04310.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Morphobiometrical and molecular study of two populations of Demodex folliculorum from humans. Parasitol Res 2011; 110:227-33. [PMID: 21647672 DOI: 10.1007/s00436-011-2476-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 05/17/2011] [Indexed: 10/18/2022]
Abstract
A morphobiometrical and molecular study of two populations of Demodex folliculorum from humans isolated from different habitats, skin and eyelashes follicles, were carried out. Morphological and biometrical studies revealed two closely related populations with any distinctive characteristics. For molecular study, a 436-bp region of the 16S rDNA gene and a 453-bp region of the cytochrome oxidase I (COI) gene from individual mites of each population considered were sequenced. Intraindividual and interindividual sequence variation was studied in both populations. Our data show that 16S rDNA is not a useful marker to discriminate between populations; however, COI gene sequences can help to identify the two populations considered, which are morphologically very close and difficult to separate by classic methods. These results are in agreement with the morphological and biometrical differences detected between D. folliculorum from eyelashes and human skin. This study appeals for the revision of the taxonomic status of the D. folliculorum populations, as well as for the species included within genus Demodex.
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