Definiton
Diseases caused by mites in general are called acariosis, whereby certain mite species can cause characteristic skin rashes. While house dust allergy is a common disease caused by certain excretion products of house dust mites, a highly itchy skin rash caused by so-called digger mites, which lay eggs in corridors under the skin, is rather less common – the latter is best known under the clinical picture of scabies. The itching of the skin rash caused by mites is often accompanied by differently sized, often reddish papules, nodes or blisters.
Causes
The skin rash caused by mites is usually caused by so-called female grave mites or scabies mites (Sarcoptes scabiei). They are able to bore through the uppermost skin layer and deposit eggs and excrements in the smallest channels. The excretion products cause the characteristic symptoms (itching, wheals, blisters, papules, etc.). The laying of eggs, on the other hand, serves for reproduction. With an intact immune system and adequate hygienic conditions, this disease occurs very rarely or is kept at a low level of severity.
Diagnosis
The diagnosis of suffering from a skin rash caused by mites can often be made based on medical history and clinical appearance alone. Classically, the itching of the rash occurs most during the night and often affects several family members or several people in the immediate vicinity (e.g. community facilities) at the same time. To confirm the diagnosis, the treating family doctor or dermatologist can also examine the skin with a so-called dermatoscope to detect the small mites directly or take a small skin sample from an affected area of skin to examine it under a microscope.
Symptoms
Characteristic symptoms of the rash caused by mites (scabies) are similar to those of an allergic reaction. The first characteristic feature can (but does not necessarily have to be) reddish, often comma-shaped, up to 1cm long ducts in the skin (preferred location in the spaces between the fingers and toes), at the end of which the mites can stand out as tiny black dots. Approximately 3-4 weeks after the mite infestation, the severe itching with a rash develops, which is characterized by wheals, blisters, papules and crusts. It is strongest at night and in bed warmth and is aggravated by scratching.
All articles in this series:
