Rotating Through the Demodex World with an Icon: Part 1
Michael S. Cooper, OD
Dr. Katherine Mastrota is Director of Optometry for the New York Hotel Trade Council Employee Benefit Funds. She and her team of 18 are responsible for providing expert, comprehensive primary and secondary eye care to a patient base of 95K individuals.
Throughout the years from my vantage point as a student and clinician observer, Katherine has engineered instrumentation, lectured extensively, taken part in numerous journal/literature writings, and shaped medicine with her astute participation on a multitude of advisory steering committees. Most importantly though, she has been a wonderful scientific ambassador that all of us should strive to be some day. That's why she is a legendary icon in my book! Please enjoy the interview.
1. Now that the cat is out of the bag on the icon, tell us something unique that the audience may not know about you.
I love fairy tales and mystery stories. I am a HUGE Columbo fan (the television show). I think that patient care, especially dry eye and ocular surface disease management, satisfies both of these interests. Every case is a mystery to unwind. I love working through the patient history clues and exam data to reach a diagnosis and develop a management plan. Then, hopefully, the fairy tale part is when the patient lives "happily ever after" with clear and comfortable vision.
2. As you know, Demodex has been a hot topic for the past few years. What is your take on their impact within the ocular surface biome?
Certainly, the ocular biome is as extraordinarily complex and dynamic as the tear film that monitors it. Populations of symbiotic bacteria maintain a protective balance for the ocular surface. Challenges to the ocular surface, including the normal flora itself, may lead to a subtle shift in type and numbers of bacterial populations, upsetting this delicate balance and allowing for subsets of bacteria, normally commensal, to take on a more virulent nature.
Demodex organisms themselves are associated with their own families of bacteria. We don’t know how these microscopic organisms fit into the biome-balance puzzle.
It is possible that the Demodex story is similar in nature: populations of mites exist harmlessly in their chosen environment (skin pores, body hair or eyelash follicles, oil-producing glands) until something stimulates a population explosion, or a shift in the mite from benign to inflammation-provoking.1,2 There has yet to be a study to highlight a positive role for Demodex that could play a critical function in skin maintenance akin to the important role of gut bacteria; however, we should consider that this may be the case.
3. Digging deeper (pun intended), do you believe these mites and various bacterial species such as Staph are in some respect competitive co-inhabitants in an overcrowded space for which amplifies a component of the inflammatory response we see on the lid margin and periorbital eyelid and cheek areas?
Our bodies are teeming with microscopic life.3 There is a fine line between calm symbiosis and environmental upheaval of these sub-populations that can result in inflammation, infection and loss of local function. For example, bacterial surveillance on our skin (our largest organ) and in our gut protects us from non-habitant, or particularly unwanted, foreign microbes. Without the vigilance of these ride-along organisms, we would be perpetually suffering infection, malnourishment, and open to all sorts of pathogenic squatter organisms.3,4 The flip side, of course, is when changes in the host allow for resident microorganisms to thrive and reach abnormally high populations levels. Quorum sensing (the ability to detect and to respond to cell population density by gene regulation) in bacteria can incite benign commensals to become virulent.5 Regulation of gene expression or gene regulation includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products. Sophisticated programs of gene expression are widely observed in biology, for example, to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. I wonder if there is a parallel pathway or mechanism for Demodex, or perhaps a product of its own resident bacteria, which causes what we believe to be Demodex-associated ocular surface and blepharitis.
Proposed mechanisms for manifest Demodex blepharitis include but are not limited to an altered immune system, especially in immune-deficient individuals, hypersensitivity against the mite itself and/or an inflammatory immune response to antigenic proteins related to a bacterium isolated from a D. folliculorum mite, Bacillus oleronius.6
In the voice of Peter Falk (Columbo), one more thing…Dr. Mastrota will be back to discuss her diagnostic protocol, treatment methods, and practice management pearls for those interested in creating a new niche in this trending area.
Stay tuned and humble!
Hom MM, Mastrota KM, Schachter SE. Demodex. Optom Vis Sci. 2013; 90(7):198-205.
Mastrota KM. Method to identify Demodex in the eyelash follicle without epilation. Optom Vis Sci. 2013; 90(6):172-174.
Naik S, Bouladoux N, Wilhelm C, et al. Compartmentalized Control of Skin Immunity by Resident Commensals. Science. 2012; 337(6098):1115-1119.
Rutherford ST, Bassler BL. Bacterial Quorum Sensing: Its Role in Virulence and Possibilities for Its Control. Cold Spring Harb Perspect Med. 2012; 2(11):a012427.
O’Reilly N, Bergin D, Reeves EP, et al. Demodex-associated bacterial proteins induce neutrophil activation. Br J Dermatol. 2012; 166(4):753–760.
Michael S. Cooper, OD currently practices and is the Director of Research and Technological Innovation at Solinsky EyeCare in the Greater Hartford area. He specializes in anterior segment disease, treating a variety of conditions including dry eye and external lid diseases, allergy, and uveitis. He has produced research, participated on expert ocular surface disease round tables, and lectured domestically on topics such as corneal disease states, uveitis management, Lyme disease, emerging pathogens, complex glaucoma management, sports-related eye injuries in children, and AMD pedigree relationships. Currently, he is actively involved in global clinical studies for novel anti-infective therapeutics, ocular surface diagnostic validation, and AMD genetic research.