How to see a scabies mite? - briefly
Examine skin scrapings under a microscope at 10‑40× magnification; the mite appears as a tiny, oval organism about 0.3 mm long with four pairs of legs. A dermatoscope can also reveal the characteristic “delta sign” within the burrow.
How to see a scabies mite? - in detail
The scabies mite (Sarcoptes scabiei) measures 0.2–0.4 mm in length, making it visible only under magnification. Direct observation requires proper specimen collection, suitable microscopy, and, when necessary, staining techniques.
Collecting a specimen involves scraping the burrow or skin surface with a sterile scalpel or a fine curette. The material should be placed on a glass slide with a drop of mineral oil or a drop of 10 % potassium hydroxide solution to clear keratin. For increased contrast, a few drops of Lugol’s iodine or a Giemsa stain may be applied.
Microscopic examination proceeds as follows:
- Use a light microscope equipped with a 10×–40× objective; higher magnification (100× oil immersion) reveals detailed morphology.
- Locate the mite’s characteristic oval body, four pairs of legs, and the anterior mouthparts (gnathosoma).
- Identify the egg sacs, which appear as small oval structures containing 2–3 eggs, often situated within the same burrow.
- Examine the surrounding skin for scybala (fecal pellets) and the linear or serpentine tracks left by the mite’s movement.
Digital dermoscopy can provide a non‑invasive view of superficial burrows, but the mite itself remains invisible without magnification. Confocal laser scanning microscopy offers in‑vivo imaging at cellular resolution, though it is typically reserved for research settings.
Interpretation criteria:
- Presence of a live mite, egg, or egg sac confirms infestation.
- Detection of scybala or characteristic burrow patterns supports diagnosis when the organism is not directly observed.
Proper specimen handling, appropriate magnification, and optional staining are essential for reliable visualization of the scabies mite.