Counting Demodex Mites with a Confocal Laser Microscope

Written by on June 25, 2012 in Demodex Mites with 2 Comments


This paper describes a new way of counting facial demodex mites. A type of microscope called a Confocal Laser Scanning Microscope was used to look for `roundish or lengthy cone-shaped structures’ on the skin, and these were counted as demodex mites. This type of approach is less invasive than a scraping or biopsy.

Thus rosacea sufferers now have a confirmed, non-invasive way of quantifying the number of demodex mites that are present on their skin.

All we need it easy access to such a microscope. The microscope pictures is the Zeiss LSM 700, and is an example of an industrial standard for a CLSM. Pricing for one of these beasts is not available online, so you should assume that they are very expensive and only available in professional and academic offices.

The advantage of a confocal microscope is that it can merge multiple images from multiple depths of field such that the surface of the skin is easy to visualise and thus the mites are easy to see.

How Many Mites are Too Many?

A high demodex density is considered to be more than 5 mites per square cm.

I assume from the description of the test that a method was devised where you could place your face near the microscope, eliminating the need to remove a sample of skin to prepare a specimen. The abstract doesn’t detail how this works, only that the method was less invasive than a scraping or biopsy.

Other Methods

A 2010 paper compared the microscopic examination of fresh secretions of sebaceous glands with standard surface skin biopsy and concluded that a biopsy was a more reliable method of clinical diagnosis.

The count of mites using the biopsy was higher in most cases, suggesting a more accurate count would be possible with a direct physical sample from a biopsy.

Latest Abstract

Non-invasive in vivo detection and quantification of Demodex mites by confocal laser scanning microscopy.

Br J Dermatol. 2012 Jun 20.

Sattler EC, Maier T, Hoffmann VS, Hegyi J, Ruzicka T, Berking C.

Background: In many Demodex-associated skin diseases Demodex mites are present in abundance and seem to be at least partially pathogenic. So far all diagnostic approaches such as scraping or standardized superficial skin biopsy are (semi-) invasive and may cause discomfort to the patient.

Aim of this study was to see whether confocal laser scanning microscopy (CLSM) – a non-invasive method for the visualization of superficial skin layers – was able to detect and quantify Demodex folliculorum in facial skin of patients with rosacea.

Material and Methods: 25 patients (34-79 years of age) with facial rosacea and 25 age- and gender-matched normal controls were examined by CLSM.

Mosaics of 8×8 mm and 5×5 mm were created by scanning horizontal layers of lesional skin and quantification of the mites per follicle and per area as well as of the follicles per area was performed.

Results: In all patients Demodex folliculorum could be detected by CLSM and presented as roundish or lengthy cone-shaped structures.

CLSM allowed the quantification of Demodex mites and showed significant differences (p-value < 0.0001): The mean number of mites was 165.4 per 8×8 mm area and 94.2 per 5×5 mm area in the patients compared to 34.7 and 22.4, respectively, in the controls.

The corresponding mean number of mites per follicle was 0.7 and 0.8, respectively, in the patients and 0.1 and 0.2, respectively, in the controls.

Conclusion: With the help of CLSM it is possible to non-invasively detect, image and quantify Demodex mites in facial skin of patients with rosacea.

Related Articles


Read more about: Demodex Mites

About the Author

About the Author: David Pascoe started the Rosacea Support Group in October 1998. .

Follow Rosacea Support

Subscribe via RSS Feed

2 Reader Comments

  1. Brady Barrows says:

    Thanks David for finding a photo of the device. Hopefully this device will be used in the future to obtain some quantitative data on the number of cases of demodectic rosacea vs other variants and subtypes of rosacea. I have added your photo and credit to this article on my post about Demodectic Rosacea here:

  2. rebecca says:

    How do I find someone to text to see if I have demodex mites?

Leave your comment here


Discover more from Rosacea Support Group

Subscribe now to keep reading and get access to the full archive.

Continue reading

Subscribe to Rosacea News

Enter your email address to receive the latest news about rosacea in your inbox.