Fthyriasis

The causative agent is the pubic louse Phthirus pubis (genus en: Phthirus , family en: Pthiridae , order Phthiraptera , class Insecta , type Arthropoda , kingdom Animalia ). The size of the male is about 1 mm, the female is 1.5 mm. The parasite feeds on human blood, often with small interruptions, the volume of a single bloodsucking is 0.1 ml, the duration of fasting is up to 12 hours.

Pubic louse can be transmitted from a sick partner to a healthy one, moving through the pubic hair during sexual intercourse. Also, infection can occur through bedding and underwear while sleeping in the same bed. Often cases of infection in baths, saunas, pools.

In the presence of severe itching, patients comb the lesions. In this case, lichenization and excoriation are formed. Secondary infection may join. Sometimes blue spots appear on the skin. This color is formed due to the breakdown of hemoglobin by the action of lice saliva enzymes. Rashes are localized in the inguinal region and in the armpits. Hips, trunk, chest, face may be affected.

Sometimes the ploshchits are located in the area of ​​the auricles, cervical-occipital region, with developed hair cover of lice can be found throughout the body.

Phytiasis is considered a sexually transmitted disease. If there is phthyriasis, there is a 30% chance of having another sexually transmitted disease at the same time.

With bites of clothes ^{[ specify ]} lice itching is not as pronounced as with pediculosis, but there is also a reaction to bites due to insect saliva entering the bloodstream and subsequent reaction with blood in the form of bluish-blue rounded spots ( Maculae coerulae , maculae caeruleae ). The spots do not disappear when pressed, have a size of 5 to 15 mm. These spots remind spotty syphilide (see. Syphilis ), syphilitic or typhoid roseola .

Papules and vesicles appear on the skin , with intense itching - excoriation, peeling, hemorrhagic crusts and complication of pyoderma . Pustules with impetinization, dermatitis , an eczema-like reaction may develop.

A differential diagnosis with the appearance of spots should be carried out with typhoid roseola, syphilis .

Pubic pediculosis treatment today is carried out with aerosols containing pyrethrin , which has neurotoxicity for pubic lice. The drug is sprayed with a uniform layer over the entire affected surface, then after exposure (30 minutes - 1 hour), a toilet with soap under running water is carried out.

Bed linen, clothes must be washed in hot water (preferably boiling). Then, after ironing, it is sealed in plastic bags for a period of at least 3 days. Treatment is indicated for all sexual partners with whom contacts have taken place for 1-2 months.

• Pediculosis
• Lice

• Samuel Lilienthal. “Treatment of skin diseases”, 2005.

• Pediculosis and phthiasis - new in diagnosis and therapy
• Skin Diseases: Phytiasis (link not available)
• Fthyriasis