Erysipelas

Definition

Erysipelas is a superficial bacterial skin infection that is characteristically

extends into cutaneous lymphatics . It was referred to as:

Saint Anthony's Fire (= ergotism or erysipelas or Herpes zoster )

•Bacterial inoculation into an area of skin trauma is the initial event in

developing erysipelas.

Pathophysiology

The source of the bacteria in facial erysipelas is often the host's naso-pharynx, and a history of recent streptococcal pharyngitis has been reported in up to one third of cases.

Pathophysiology

Pathophysiology

Lymphoscintigraphy in patients with a first-time episode of lower extremity erysipelas has documented lymphatic impairment in both affected and non affected legs.

regional lymph node swelling and tenderness

* Streptococci are the primary cause of erysipelas. * Most facial infections are attributed to group A streptococci, *lower extremity infections being caused by non–group A streptococci.

Causative organism

causes•Streptococcal toxins are thought to contribute to the brisk inflammation that is pathognomonic of this infection.

*No clear proof has emerged that other bacteria cause typical erysipelas, although they clearly coexist with streptococci at sites of inoculation.

causesRecently, atypical forms reported to be caused by : * Streptococcus pneumoniae, *Klebsiella pneumoniae, * Haemophilus influenzae, *Yersinia enterocolitica, *Moraxella species, they should be considered in cases refractory to standard antibiotic therapy.

RaceErysipelas infections affect persons of all races.

Sex•Erysipelas is common in females. • at an earlier age it is more in males ( more activities).• However predisposing factors, rather than gender, account for any male/female differences in incidence.

Age All age groups are susiptable.The peak incidence at 60-80 years old, especially in patients := At high-risk . = immuno-compromised . = those with lymphatic drainage problems (eg, after mastectomy, pelvic surgery, bypass grafting).

Clinical

symptomsProdromal symptoms:

malaise . chills .

high fever. often begin before the onset of the skin lesions and usually are present within 48

hours of cutaneous involvement..

symptoms Pruritus .

burning . tenderness .

are typical complaints

Physical

Erysipelas begins as a small

erythematous patch that

progresses to a fiery-red,

indurated , tense, and shiny plaque.

The lesion classically exhibits raised sharply demarcated advancing margins.

Local signs of inflammation

warmth, edema,

tenderness are universal.

Lymphatic involvement often is manifested by

overlying skin streaking and

regional lymphadenopathy

More severe infections may

exhibit numerous vesicles and bullae

along with petechiae and

even frank necrosis.

Erysipelas of

the face

Erysipelas Of

the leg

Erysipelas the

buttock

Erysipelas of

the ear Pena

Differential Diagnoses

Differential Diagnoses

1) Erythema Annulare Centri-fugum2) Stasis Dermatitis3) Cellulitis4) Erysipeloid

Erythema Annulare Centrifugum

* Eruptions occur at any age. * begins as small raised pink-red spot that slowly enlarges and forms a ring shape while the central area flattens and clears. There may be an inner rim of scale.

Erythema Annulare Centrifugum

Lesions most often appear on the thighs, legs, face, trunk and arms. linked to underlying diseases , viral , bacterial or even tumor.

Stasis Dermatitis

cellulitis

Erysipeloid * acute bacterial infection of traumatized skin. * caused by Erysipelothrix rhusiopathiae (gram positive rod-shaped bacterium), which cause animal and human infections. * Direct contact between infected meat and traumatized human skin results in Erysipeloid. •more common among farmers, butchers, cooks, homemakers. * Lesions most commonly affect the hands.

Erysipeloid

* Lesions consist of well-demarcated,

bright red-to-purple plaques with a smooth, shiny

surface.•Lesions are warm

and tender.

Laboratory Studies

Laboratory Studies* In classic erysipelas, no laboratory workup is required for diagnosis or treatment.* Cultures are best reserved for immunocopromized patient in whom an atypical etiologic agent is suspected.

Imaging StudiesImaging studies are not usually indicated and are of low yield. MRI and bone scintigraphy are helpful when early osteoarticular involvement is suspected. In this setting, standard radiographic findings typically are normal.

Histological FindingsThe histological hallmarks of erysipelas are *marked dermal edema, *vascular dilatation, *streptococcal invasion of lymphatics & tissues. This bacterial invasion results in a dermal inflammatory infiltrate consisting of neutrophils and mononuclear cells. The epidermis is often secondarily involved. Rarely, bacterial invasion of local blood vessels may be seen.

Treatment

Hospitalization for close monitoring and IV. antibiotics is recommended for :1) severe cases.2) infants.3) elderly patients.4) patients who are immune-

compromised.

Medical Care* Elevation and rest of the affected limb are recommended to reduce local swelling, inflammation, and pain.* Saline wet dressings should be applied to ulcerated and necrotic lesions and changed every 2-12 hours, depending on the severity of the infection.

* penicillin has remained first-line therapy.

administered orally or IM. for 10-20 days.Dosing : AdultPenicillin G procaine: 0.6-1.2 million U IM bid for 10 dPenicillin VK: 250-500 mg PO qid for 10-14 dPediatric : Penicillin G procaine: <30 kg: 300,000 U/d >30 kg: Administer as in adults Penicillin VK:<12 years: 25-50 mg/kg/d PO divided tid/qid; not to exceed 3 g/d>12 years: Administer as in adults

Medical Care

Medical Care

*A first-generation cephalosporin or macrolide, such as erythromycin or azithromycin, may be used if the patient has an allergy to penicillin. DosingAdult250-500 mg PO qid for 10 dPediatric30-50 mg/kg/d (15-25 mg/lb/d) PO divided q6-8h; double dose for severe infection.

•Two new drugs:• roxithromycin & pristinamycin, have been reported to be extremely effective in the treatment of erysipelas. * Several studies have demonstrated greater efficacy and fewer adverse effects with these drugs compared with penicillin.

*Currently, FDA has not approved these drugs in the United States, but they are in use in Europe.

Recurrent erysipelas

Patients with recurrent erysipelas should be educated regarding :•local antisepstic . •general wound care. •Predisposing lower extremity skin lesions (eg , tineapedis , toe web intertrigo , stasis ulcers) should be treated aggressively to prevent super-infection.

Recurrent erysipelas

•Long-term prophylactic antibiotic therapy generally is accepted, but no true guidelines are available. •Treatment regimens should be tailored to the patient.

•One reported regimen is benzathine penicillin G at 2.4 MU IM. every 3 weeks for up to 2 years . Two-week intervals have also been used.

Recurrent erysipelas

Surgical CareDebridement is necessary only in severe infections with necrosis or gangrene.

Complications

1) The most common complications of erysipelas are : * abscess,* gangrene, * Thrombophlebitis .

Complications

Complications

2) Less common complications (<1%) are :

*acute glomerulonephritis , *endocarditis , *septicemia, *streptococcal toxic shock

syndrome.

Prognosis* The prognosis for patients with erysipelas is excellent. * local recurrence has been reported in up to 20% of patients with predisposing conditions