Abscess L02.9

Localized, encapsulated inflammation in the epidermis, hair follicles, in eccrine or apocrine sweat glands, in the dermis and/or subcutis, caused by pus-inducing substances or pathogens (bacteria or fungi), accompanied by tissue melting, and melting centrally after 4-5 days.

Pus is the constellation of neutrophilic granulocytes, cellular debridement, and liquefied tissue. Abscess is the name given to the purulent, fluctuant, cutaneous or subcutaneous formation of a cavity. Epidermal or infundibular accumulations of pus are called pustules or, in the minus variant, microabscesses (e.g. Munro microabscess in psoriasis vulgaris).

Notice. The microabscess named after Pautrier, which consists of lymphocytes and not neutrophilic granulocytes, is to be understood as a misnomer.

Mostly staphylococci (especially Staphylococcus aureus), less frequently gram-negative germs (E. coli, Proteus mirabilis) or mixed flora. The typical manifestation is determined by the pathogenic properties of the pathogens. Staphylococci produce the enzyme coagulase, which activates coagulation and slows down the spread of inflammation in the interstitium.

Dead parasites or their remains are further causes of abscess formation.

Fungi can also lead to abscesses in rarer cases.

Bacterial follicular and non follicular pustules are treated locally with antiseptic and internally with antibiotics. Dermal abscesses must be sufficiently incised and drained; penicillinase-resistant penicillin, possibly after antibiogram.

Alternative: Clindamycin 3x300mg/day p.o. for 10 days

Alternative: Trimethoprim-Sulfmethoxazole 2x 160TMP/800 SMXmg/day p.o. over 10 days

1. Miller LG et al (2015) Clindamycin versus trimethoprim-sulfamethoxazole for uncomplicated skin infections.N Engl J Med 372:1093-1103