Pathophysiology of scabies

The pathophysiology of scabies is worthwhile and everyone ought to know the cardinal symptoms and how to prevent them.


Oftentimes people of all races and backgrounds are affected by the infestation of sarcoptes scabiei mite, as well as the human itch mite worldwide, this infestation is generally known as scabies.

Sarcoptes scabiei,  falls under the class of Arachnida and infect both human and animal at varying degrees.


Introduction to the pathophysiology of scabies

A readily treatable infestation, scabies remains common primarily because of diagnostic difficulty, inadequate treatment of patients and their contacts, and improper environmental control measures. Scabies is a great clinical imitator.

Its spectrum of cutaneous manifestations and associated symptoms often results in delayed diagnosis. In fact, the term “7-year itch” was first used with reference to persistent, undiagnosed infestations with scabies

In humans, the availability of mites will determine how contagious the infestation will be.

for instance, incrusted or Norwegian scabies {because it was first analyzed in Norway} is highly contagious due to thousands of these microscopic mites present. The availability of these mites is because of a compromised immune system like in the case of HIV/AIDS.


Pathophysiology of scabies

The pathogen responsible for scabies is sarcoptes scabiei mite. This infectious agent burrows under the skin using its mouth and the sophisticated front legs, the male and female act synergistically.

When a fertile female finds its way under the skin, as it burrows it lays eggs which later hatch to larva. The larva attacks the hair follicle under the skin and equally makes the skin vulnerable to opportunistic dermatological diseases.

The movement of the mites brings about the itching sensation which gets worsens in the presence of eggs. The pathology is more mechanical than chemical.

Cardinal symptoms of scabies

Unrelenting Itching is brought about by the movement of the mite under the skin.

Uneasy scratching of the affected part might equally make the skin vulnerable to secondary infections like dermatitis. Reddish rashes of varying sizes are equally pronounced.

Others may include;

The hotness of the affected area `and Sores

The part of the body, mostly affected by this parasitic mite are the hidden areas of the body and joints like the in between the fingers, armpit, elbow, wrist, knee, genitalia, and gluteus.

The contraction of scabies is by direct contact with an infected person or by using the same bedding with an infected fellow.

Types of scabies

  • Typical scabies
  • Nodular
  • Crusted

Typical scabies on the pathophysiology of scabies

Typical or classic scabies is the most common. It causes an itchy rash on the hands, wrists, and other common spots. However, it doesn’t infest the scalp or face.

Classic scabies has a distribution involving the axillae, elbow flexures, wrists and hands, and genital area. In infants and small children, burrows are commonly located on the palms and soles.

One- to 3-mm erythematous papules and vesicles are seen in typical distributions in adults. The vesicles are discrete lesions filled with clear fluid, although the fluid may appear cloudy if the vesicle is more than a few days old.

Nodular scabies on the pathophysiology of scabies

as the name implies this type of scabies may develop as itchy, raised bumps, or lumps, it may also present as persistent nodules for months even after specific treatment of scabies. It oftentimes appears around the genital areas, groin or armpit.

Crusted scabies on the pathophysiology of scabies

pathophysiology of scabies

Some people with scabies may develop another form of scabies known as Norwegian scabies or crusted scabies. This is a more severe and extremely contagious type of scabies. People with crusted scabies develop thick crusts of skin that contain thousands of mites and eggs which usually arise from individuals that are immune-compromised.

How can one prevent the spread of Scabies?

The best way to prevent getting scabies is to avoid direct skin-to-skin contact with a person known to have scabies.

It’s also best to avoid unwashed clothing or bedding that’s been used by a person infected with scabies. Make sure you wash all your bedding materials in hot water that reaches 122°F (50°C).

These items should then be dried in the dryer on very high heat for at least 10 to 30 minutes.

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