|Establishing patient history is a useful first step in the diagnosis of scabies. A definitive scabies diagnosis requires the identification of mites, eggs, eggshell fragments, or feces in the skin.||Adult female and her eggs in the top left burrow. Scabies lesions are characterized by well-defined intraepidermal vesicles|
Primary Methods of Diagnosis:
1. Skin scrapings: Physician uses a #15 blade to scrape a burrow site. The scraping should be mounted with a drop of 10% potassium hydroxide or mineral oil and observed under a microscope. Since there are so few mites in the entire body, they are difficult to find. Accordingly, failing to identify a mite does not rule out a positive scabies diagnosis.
2. Skin biopsy: If skin scrapings are inconclusive, a biopsy can confirm the presence of scabies mites. However, mites may not be in the stratum corneum, in which case the histology would reveal a nonspecific, hypersensitivity reaction.
Differential diagnosis of scabies is not rare. The parasitic disease is commonly mistaken for:
1. Insect bites (they resemble scabies without the burrow marks)
2. Eczema variations, particularly atopic dermatitis
|Scabietic burrow containing eggs with embryos||Norwegian scabies: mites in all developmental stages are arranged in hierarchical tiers|