A furuncle is an acute purulent inflammation caused by pyogenic bacteria invading the hair follicle and surrounding tissues. A single lesion is called a furuncle, presenting as a painful, hemispherical red nodule. Later, the center undergoes purulent necrosis and eventually ruptures or is absorbed. Multiple and recurrent occurrences are termed furunculosis. It commonly affects areas such as the head, face, neck, and buttocks, and is more frequently seen in summer and autumn.

bubble_chart Etiology

The causative bacteria are mainly Staphylococcus aureus, followed by Staphylococcus albus, which invade hair follicles or sweat glands. Skin abrasions, erosions, etc., are conducive to bacterial invasion and reproduction. Excessive sebum secretion and frequent occupational exposure to mineral oils also predispose individuals to boils. Furunculosis mostly occurs during the hot summer months. High temperatures, humidity, and profuse sweating facilitate the invasion of pathogenic bacteria into the skin. Poor skin hygiene is a significant contributing factor. Reduced body resistance, weakness, diabetes, nephritis, anemia, and other conditions can serve as predisposing factors for this disease.

bubble_chart Clinical Manifestations

Initially, there is a small red inflammatory papule at the hair follicle, which gradually enlarges into a round nodule. The overlying skin becomes tight, with localized redness, swelling, heat, and pain. The edges are not very distinct. As the nodule matures, the center softens and becomes fluctuant upon palpation, while the surface skin thins and a yellow dot appears at the apex. Soon, it ruptures, discharging pus and necrotic tissue, immediately relieving the pain. The redness and swelling gradually subside, eventually healing and leaving a scar. Sometimes, the red, swollen nodule gradually resolves without suppuration or rupture.

Histopathology shows the formation of small abscesses centered around a hair follicle, sebaceous gland, or sweat gland. At the lesion site, the normal tissue structure is destroyed. The pus, composed of numerous pus cells, neutrophils, and necrotic tissue, contains pathogenic bacteria. After expelling pus, the area is repaired by granulation tissue, eventually forming fibrous scar tissue.

bubble_chart Treatment Measures

1. Pay attention to skin hygiene, avoid spicy and irritating foods as well as alcohol, and it's best not to consume too many sweets. Never use squeezing methods to expel pus, especially for boils on the face and upper lip. For recurrent furunculosis, identify underlying factors and eliminate internal infection foci. Check for conditions such as anemia and diabetes, and treat promptly if detected.

2. Antibiotic injections and oral administration. Apply sufficient antibiotics early. Penicillin is the first choice, but lincomycin 0.6g intramuscular injection twice daily can also be used, as well as cephalosporins, ofloxacin, and sulfonamides.

3. Autogenous vaccine or mixed staphylococcal vaccine therapy, and autologous blood therapy. Alternatively, subcutaneous injection of transfer factor 2mg/dose, twice weekly, for five weeks as one course.

4. Early-stage boils should not be incised for drainage. Mature boils that have suppurated and softened may be incised to expel pus. However, boils on the face and upper lip must never be squeezed or casually incised. For non-suppurative boils, apply pure ichthammol or ichthammol-sulfur paste daily to promote inflammation resolution.

5. Ultraviolet, infrared, or ultrashort wave irradiation can be performed to alleviate inflammation.

1. Multiple sweat gland abscesses also occur in summer, commonly seen on the head, forehead, and other areas of infants and weak postpartum women. The skin lesions are multiple subcutaneous abscesses with surface tenderness and mild inflammation. There are no pus plugs, and scars remain. It is usually accompanied by a lot of prickly heat. Commonly known as "heat rash toxin," it is also referred to as pseudofurunculosis (Pseudofurunculosis).

2. Hidradenitis suppurativa is more common in young women, with skin lesions presenting as subcutaneous nodules. These develop into subcutaneous abscesses, followed by redness, swelling, heat, pain, and eventual ulceration and scarring. The lesions frequently occur in the armpits, groin, genital and perianal areas, and around the navel.