Bacterial skin infections

Impetigo

– Infection benign contagious dermoepidermal. By germs beta-hemolytic group A streptococcus and Staphylococcus aureus, often associated on the same lesion. Transmission is by direct contact. It is favored by the lack of water and sanitation.

– Primitive forms mainly affect children. Forms complicating an itchy skin disease (pediculosis, scabies, eczema, herpes, chicken pox, etc.) are more common in adults.

Clinical signs:

– Classic form: flaccid vesicule on erythematous skin and yellowish crusts with the presence of different ages elements, leaving no scar.

Preferred locations: around the mouth and nose, members scalp. No fever.

– Bullous impetigo: large flaccid and extensive erosions bubbles anogenital among newborns and infants.

– Ecthyma impetigo digging, necrotic, leaving a scar, located in the lower limbs, favored by immunosuppression, diabetes and alcoholism.

– Rare complications:

• abscess, pyoderma, lymphangitis, osteomyelitis, septicemia;

• acute glomerulonephritis to search systematically.

Treatment:

Localised impetigo (less than 3 lesions on the same area):

• Clean with soap and water 2 times a day to dry and then apply gentian violet to 0.5%.

• For crusts soften by applying petrolatum and detach them gently.

• Keep dry (do not occlusive dressing; in children, leave uncovered buttocks, etc.).

• Cut the nails flush.

Extensive impetigo (more than 3 items or achieving several regions); impetigo

Bullous; ecthyma; Impetigo abscessed; immunocompromised patients:

• Treat locally as above.

• incise abscesses.

• Involve systematically antibiotics:

cloxacillin PO

Children: 50 mg / kg / day in 2 divided doses for 10 days

Adult: 2 g / day in 2 divided doses for 10 days

If allergic to penicillin: erythromycin PO

Child: 30 to 50 mg / kg / day divided in 2 or 3 doses for 10 days

Adult: 2-3 g / day divided into 2 or 3 doses for 10 days.

In all cases:

• Quarantine from school.

• Treat skin disease: lice, scabies, eczema, herpes, ringworm or an ENT home.

• Trace and treat contacts.

• Systematically check for proteinuria in the strip, 3 weeks after infection.

Furuncle and carbuncle

Necrotizing infection of a sebaceous follicle due to Staphylococcus aureus most often. It is favored by maceration, skin trauma, poor hygiene, diabetes, malnutrition, iron deficiency or immunosuppression.

Clinical signs:

– Boil: erythematous nodule, hot, painful pustule topped with a centered by a hair, and fluctuation, disruption and removal of necrotic product. Residual scar. Preferred locations thighs, groin, buttocks, armpits, neck, back.

No fever.

– Carbuncle: made of several boils sometimes with fever and

satellite nodes. Leaves a depressed scar.

Treatment:

– In case of single furuncle:

Clean with soap and water 2 times a day and cover with a dry dressing.

The application of warm compresses promotes spontaneous evacuation of bourbillon.

After evacuating the boil, wash and apply an antiseptic until healing.

– If you boil the face, carbuncles, multiple boils or in immunocompromised patients, treat systematically with antibiotics:

cloxacillin PO

Children: 50 mg / kg / day in 2 divided doses for 8 days

Adult: 2 g / day in 2 divided doses for 8 days

In case of allergy to penicillin:

erythromycin PO

Child: 30 to 50 mg / kg / day divided in 2 or 3 doses for 8 days

Adult: 2 to 3 g / day divided in 2 or 3 doses for 8 days

– Excision of the boil, only when the lesion is fluctuating.

– In all cases:

• Daily toilet, frequent hand washing, laundry.

• Never manipulate a furuncle of the face: there is a risk of malignant staphylococcal infection of the face (unilateral inflammation with high fever and risk of thrombophlebitis of the cavernous sinus). In this case:

cloxacillin slow IV

Children: 75 mg / kg / day in 3 injections

Adults: 3 g / day in 3 injections

Take the oral route as soon as possible, at the same doses, to complete 10 days of treatment. or if allergic to penicillin: chloramphenicol IM

Children over 2 months: 100 mg / kg / day in 3 injections

Adults: 3 g / day in 3 injections

Take the oral route as soon as possible, at the same doses, to complete 10 days of treatment.

Erysipelas

Dermo acute cellulitis, necrotizing not due to beta-hemolytic streptococcus group A. Common in adults, rare in children.

Clinical signs:

– “Big acute febrile red leg”: lupus, closet edematous, painful, lower limb with high fever, lymphadenopathy and satellite lymphangitis.

– Location possible face: very edematous closet, bilateral, with peripheral rim.

– Look for a cutaneous gateway: ulcer, wound, intertrigo.

– Local complications: most commonly superficial abscess, sometimes deep (secondary staphylococcal infection), rarely develops into necrotising fasciitis.

– Rare generalized complications: septicemia, acute glomerulonephritis, erythema nodosum.

Treatment:

Procaine benzylpenicillin IM

Children: 50 000 IU / kg / once daily

Adults: 1.5 MIU / once daily

until no fever and clinical improvement, then change to oral to complete 7 to 10 days of treatment with:

PO phenoxymethylpenicillin

Children less than one year: 250 mg / day in 4 divided doses

Children from 1 to 5 years: 500 mg / day in 4 divided doses

Children 6 to 12 years: 1 g / day in 4 divided doses

Adult: 2 g / day in 4 divided doses

or

amoxicillin PO: 50 mg / kg / day divided into 2 or 3 doses

If allergic to penicillin: erythromycin PO

Children: 50 mg / kg / day divided into 2 or 3 doses for 7 to 10 days

Adults: 3 g / day in 3 divided doses for 7 to 10 days

– Admit if marked constitutional symptoms, local complications, poor ground (chronic disease, the elderly) or if there is a risk of non-adherence to outpatient treatment.

Note: other bacteria (Staphylococcus aureus, gram-negative bacilli) may be responsible for acute dermal-hypodermal resembling erysipelas. Think about it in case of failure of treatment with penicillin and change to amoxicillin + clavulanic acid (co-amoxiclav).

– In all cases:

• Bed rest with leg elevated.

• Non-steroidal anti-inflammatory drugs are cons-indicated (risk of necrotizing fasciitis).

• Treatment of the door (ulcers, intertrigo, etc.).

• Systematically check for proteinuria in the strip, 3 weeks after infection.

Dermo-necrotizing bacterial cellulitis

Necrosis of the hypodermis and the dermis and vascular thrombosis sometimes necrosis of the superficial fascia (fasciitis). Clinical presentations vary depending on the causative organism.

The group A streptococcus is often isolated, often associated with other bacteria (Staphylococcus aureus, anaerobic, enterobacteria, enterococci).

Clinical signs:

Erythematous plaque, ill-defined, with intense pain, swelling and severe sepsis. Then develop hemorrhagic blisters and bluish or blackish, cold, hypoaesthetic. The presence of gas or crepitation on palpation is linked to certain bacteria (Clostridium perfringens, enterobacteria).

Treatment:

Necrotizing fasciitis and gas gangrene: refer

– Surgical drainage of the wound and excision of necrotic tissue.

– Antibiotic treatment (the length of treatment varies depending on the clinical course):

• Necrotizing fasciitis:

benzylpenicillin IV

Child: 600 000 IU (360 mg) / kg / day divided in 6 injections or infusions given every 4 hours

Adults: 24 MIU (14.4 g) / day in 6 injections or infusions given every 4 hours + clindamycin IV

Children: 40 mg / kg / day in 3 divided infusions every 8 hours (maximum 1.3 g / day)

Adult: 1.8 g / day in 3 divided infusions 8:00

Gas gangrene:

benzylpenicillin IV as above + metronidazole IV

Children: 30 mg / kg / day in 3 divided infusions every 8 hours (maximum 1.5 g / day)

Adult: 1.5 g / day in 3 divided infusions every 8 hours + gentamicin IM

Children and adults: 3 to 6 mg / kg / day in 2 divided injections