In humans, Erysipelothrix rhusiopathiae

Erysipelothrix rhusiopathiae

Erysipelothrix rhusiopathiae is a gram-positive, catalase-negative, rod-shaped bacterium. It grows aerobically and anaerobically and does not contain endotoxin. Distributed worldwide, E. rhusiopathiae is primarily considered an animal pathogen, causing a disease known as erysipelas in animals...

infections most commonly present in a mild cutaneous form known as erysipeloid. E. rhusiopathiae can cause an indolent cellulitis

Cellulitis

Cellulitis is a diffuse inflammation of connective tissue with severe inflammation of dermal and subcutaneous layers of the skin. Cellulitis can be caused by normal skin flora or by exogenous bacteria, and often occurs where the skin has previously been broken: cracks in the skin, cuts, blisters,...

, more commonly in individuals who handle fish and raw meat. It gains entry typically by abrasions in the hand. Bacteremia

Bacteremia

Bacteremia is the presence of bacteria in the blood. The blood is normally a sterile environment, so the detection of bacteria in the blood is always abnormal....

 and endocarditis

Endocarditis

Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves . Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or even on intracardiac devices...

 are uncommon but serious sequelae. Due to the rarity of reported human cases, E. rhusiopathiae infections are frequently misidentified at presentation.

Treatment

The treatment of choice is a single dose of benzathine benzylpenicillin given by intramuscular injection

Intramuscular injection

Intramuscular injection is the injection of a substance directly into a muscle. In medicine, it is one of several alternative methods for the administration of medications . It is used for particular forms of medication that are administered in small amounts...

, or a five-day to one-week course of either oral penicillin or intramuscular procaine benzylpenicillin

Procaine benzylpenicillin

Procaine benzylpenicillin , also known as procaine penicillin, is a form of penicillin which is a combination of benzylpenicillin and the local anaesthetic agent procaine...

. Erythromycin

Erythromycin

Erythromycin is a macrolide antibiotic that has an antimicrobial spectrum similar to or slightly wider than that of penicillin, and is often used for people who have an allergy to penicillins. For respiratory tract infections, it has better coverage of atypical organisms, including mycoplasma and...

 or doxycycline

Doxycycline

Doxycycline INN is a member of the tetracycline antibiotics group, and is commonly used to treat a variety of infections. Doxycycline is a semisynthetic tetracycline invented and clinically developed in the early 1960s by Pfizer Inc. and marketed under the brand name Vibramycin. Vibramycin...

 may be given instead to people who are allergic to penicillin. E. rhusiopathiae is intrinsically resistant

Antibiotic resistance

Antibiotic resistance is a type of drug resistance where a microorganism is able to survive exposure to an antibiotic. While a spontaneous or induced genetic mutation in bacteria may confer resistance to antimicrobial drugs, genes that confer resistance can be transferred between bacteria in a...

 to vancomycin

Vancomycin

Vancomycin INN is a glycopeptide antibiotic used in the prophylaxis and treatment of infections caused by Gram-positive bacteria. It has traditionally been reserved as a drug of "last resort", used only after treatment with other antibiotics had failed, although the emergence of...

.