| What is impetigo? | Common superficial bacterial skin infection, most commonly seen in children 2-5 yrs, older and adults can be affected, contagious, easily spread w/close contact, mostly due to S.aureus, S.pyogenes, combination.
Two types:
non-bullous (AKA impetigo contagiousum, most common form, papules surrounded by erythema, progress form pustule enlarge and break down to form thick honey crusts)
Bullous (seen in young children, flaccid bullae w/clear yellow fluid later becomes purulent, leave thick brown crust, common locations are face, extremities and diaper area) |
| What is secondarily infected skin disease? | Most common form in adults, bacteria penetrate skin barrier via scratch/injury, search systematically for pruritic dermatitis, scabies, pediculosis, eczema, herpes and chickenpox |
| How is dx of impetigo? | clinical, bacterio exam (complicated cases, resistant, abnormal)
Basic lesion/clinical aspect (bubble fragile pustule breakup honey crust, may result in polycyclic circumferential contours)
Classic location (children around mouth and all areas may be affected, general condition preserved, no fever and possible satellite lymph node) |
| What is ecthyma? | Ulcerative lesion extends to epidermis, punched out ulcers covered w/yellow crust surrounded by raised margins.
Heals slowly and may scar, S.aureus /Strep may be the cause.
Deep impetigo (ulcer of dermis GAS, precariousness, ecthyma gangrenosum, immunocompromised can be caused by pseudomonas)
Covered with thick crust and surrounded by dark inflammatory halo located on lower limbs, for adults induced by poor hygiene, immune suppression, diabetes, chronic alcoholism, caused by strep, heal slowly and leave a scar |
| How is tx of impetigo? | Topical mupirocin ointment or fucidic acid (as effective as oral Abx if localized lesion and healthy pt w/no outbreak, otherwise use Abx)
Disinfection (70% alcohol bactericidal)
Oral Abx (when extensive or affecting several people (close contact, most important is clindamycin) |
| What are complications of impetigo? | Rare (post-strep glomerulonephritis, RF)
Control of proteinuria 3 weeks post infectious episode. |
| What is folliculitis? | Superficial bacteria infection of hair follicules, small raised erythematous and occasionally pruritic pustules <5mm diameter.
Genital folliculitis may be STD, commonly S.aureus, if there has been an exposure to hot tub/swimming pool consider pseudomonas as a possible cause.
Pustules associated w/erythema in groin may be candidiasis
Variable in number (thighs, perineum, arms, thorax, back)
Clinical forms include stye (eyelash) and sycosis (beard -induced by shaving chronicity), may be pseudomonas |
| What is tx of folliculitis? | Antibacterial soap, superficial pustules drain and rupture spontaneously.
Oral/topical anti staph mupirocin/retapamulin, clindamycin, deep lesions of folliculitis small follicular abscess should be drained |
| What is a furuncle/boil? | A furuncle (boil) is an acute, round, tender, circumscribed, perifollicular abscess that generally ends in central suppuration.
Deep and necrotic infection of the pilosebaceous follicle
S. aureus +++. If recurrent abscess evolution undergoing small family epidemics: toxinogenic research infection (Panton-Valentiner leucocidinresponsible for necrosis) and chronic carriage
Clinical feature: inflammatory papule or nodule, painful, centered by a pustule on a hairy area (the hair has disappeared due to necrosis); evolution towards a central necrotic zone in a few days |
| What is furuncle differential? | • Other infectious folliculitis: ->fungal: dermatophytes (kerion of the scalp: inflammatory dermatophyte, folliculitis to pityrosporum), Candida albicans, ->gram-negative bacillae
• Pseudofolliculitis (non infectious): Crohn's disease,
eosinophilic folliculitis
• Hidradenitis suppurativa (Verneuil's disease): chronic
inflammation of the pilosebaceous follicles and sweat
glands in areas rich in apocrine glands (axillary, sub- mammary and anoperineal folds)
• Epidermal inflammatory cyst or superinfected cyst:
Preexisting cyst (face) |
| What are furuncle complications? | • Anthrax: conglomerate of several boils
• Furunculosis: boils of chronic evolution, disrupted role of triggering factors such as diabetes or immunosuppression
• Primary abscess
• Lymphangitis
• Systemic complications (very rare): bacteremia,
septic secondary localizations
• Malignant Staphylococcal disease of the face:
emergency case, rare |
| What is malignant staph disease of the face? | • Secondary to the inadvertent manipulation of a
furuncle of the face localized in an area delimited
by the internal canthus, the labial commissure
and the wing of the nose
• Decreasing of the general state, fever, with
edema of the face, possible indurated venous
cord palpable
• Mechanism: superficial septic thrombophlebitis;
severe complication: thrombophlebitis of the
cavernous sinus (vital risk involved) |
| What is a carbuncle? | A carbuncle is a coalescence of several inflamed follicles into a single inflammatory mass with purulent drainage from multiple follicles
• Furuncles and carbuncles are a subtype of abscesses, which preferentially occur in skin areas containing hair follicles exposed to friction and perspiration Common areas include the back of the neck, face, axillae, and buttocks
• Usually caused by Staphylococcus aureus
• Patients are commonly treated with oral antibiotics
• For a solitary small furuncle: warm compresses to promote
drainage may be sufficient
• For larger furuncles and carbuncles: manage as you would an abscess |
| What is tx of folliculitis and boils? | General hygiene measures (wash, don't handle boil)
• Local antiseptic care in a topical form (solution, creams,
ointments): chlorhexidine, polyvidone iodine. .
For boils: systemic oral antibiotic therapy active on the
S. aureus, if comorbidities and / or risk of
complications: penicillin group M (oxacillin or
cloxacillin). Macrolides or pristinamycin in case of
allergy and / or contra-indication • duration of
treatment: 10 days
• In case of furunculosis: In addition to the previous
measures:
• Disinfection of the portages, armpits, perineum,
nasal vestibules and external auditory canal,
• Antiseptic toilet and application (repeated,
sequential) of topical antibiotic (fucidic acid,
mupirocine except on the mucous membranes ...) |
| What is whitlow (panaris)? | • Infection of the ungual fold
• Elemental lesion: periungual erythematous
and edematous fold, painful
• Treatment: local antiseptics; oral antistaphylococcal antibiotic in case of resistance and/or collection and / or complication; incision and drainage in case of purulent collection |
| What is abscess? | • A skin abscess is a collection of pus within the
dermis and deeper skin tissues
• Present as painful, tender, fluctuant and
erythematous nodules
• Often surmounted by a pustule and surrounded
by a rim of erythematous edema
• Often absent fever, lymphangitis and / or
sometimes associated satellite adenopathies. Good general condition
• Spontaneous drainage of purulent material may
occur |
| What is tx of abscess? | • Abscesses require incision and drainage (I & D) Most experts recommend clearing pus and debris and probing the entire cavity following incision and drainage
• Antibiotics are recommended for abscesses associated with: Severe
or extensive disease (e.g., involving multiple sites)
• Rapid progression in presence of associated cellulitis
• Signs and symptoms of systemic illness
• Associated comorbidities or immunosuppression
• Extremes of age
• Abscess in an area difficult to drain (e.g., face, hand, or genitalia)
• Associated septic phlebitis
• Lack of response to I&D alone |
| What is lymphangitis? | • Due to S. aureus or Streptococcus pyogenes
•Clinical appearance:
-linear inflammatory erythematous lines between the site of infection and the first regional lymph node -palpable lymph nodes -fever +/-, general condition preserved
•Treatment: systemic antibiotherapy linked to
bacteriological culture |
| What is superficial septic thrombophlebitis? | • Superficial septic venous thrombosis
• Linked to thrombogenic activity of S. aureus, risk
of deep spread and septic emboli
• Clinical presentation: Common form: Venous
Inflammatory cord at the point of infusion,
indurated on palpation, fever
• Treatment: Removal of catheter / gateway to an
infection. Antiseptics; systemic antibiotic therapy
if resistance / complication; rare form: malignant
staphylococcal disease of the face |
| What is cellulitis? | • Cellulitis is a very common infection occurring in up to
3% of people per year
• Most do not require hospitalization
• Results from an infection of the dermis that often
begins with a portal of entry that is usually a wound,
maceration between toes (strepto component), or
fungal infection (e.g., tinea pedis)
• Presents as a spreading erythematous, non-fluctuant
tender plaque
• More commonly found on the lower leg
• Streaks of lymphangitis may spread from the area to
lymph nodes |
| What are risk factors of cellulitis? | • Risk factors for cellulitis include: Local trauma (bug
bites, laceration, abrasion, puncture wound)
– Spread of a preceding or concurrent skin lesion
(furuncle, ulcer) Secondary cellulitis from blood-borne
infection or from direct spread of subjacent infections (e.g.
osteomyelitis) is rare
• Following a preexisting skin infection due to compromise of skin barrier (intrerdigital strep, tinea pedis)
• Inflammation (local dermatitis, radiation therapy)
• Edema and impaired lymphatics in the affected area |
| What is etiology of cellulitis? | • 80% of cases are caused by gram positive organisms
• Group A streptococcus is most common; other strep less so
• Staphylococcus aureus is less common but occurs with open wound or penetrating trauma as with needle injection with
drug abuse
• Think of other organisms if there have been unusual
exposures or conditions: Pasteurella multocida (animal
bites)
• Eikenella corrodens (human bites)
• MRSA (with concurrent MRSA elsewhere/illicit drug
use/purulent drainage) |
| What is cellulitis tx? | • It is important to recognize and treat cellulitis early as untreated cellulitis may lead to sepsis and death
• The following guidelines are for empiric antibiotic therapy: For outpatients with nonpurulent cellulitis: empirically treat for β-hemolytic streptococci (group A streptococcus) as cephalexin, amoxicillin, amoxicillin-clavulanate, dicloxacillin, or clindamycin
• For outpatients with purulent cellulitis (purulent drainage or exudate in the absence of a drainable abscess)/injection drug use/other penetrating trauma/MRSA presence elsewhere: empirically choose treatment to cover community-associated MRSA as well as strep, as clindamycin; work with dermatology and infectious disease specialists
• For unusual exposures: cover for additional bacterial species based on such exposure; work with dermatology and infectious disease specialists |
| How is cellulitis monitoring? | • Monitor patients closely and revise therapy if there is a poor response to initial treatment; usually a 5 day course of antibiotics is sufficient
• Treat underlying derm disorder/condition, as venous eczema
• Elevation of the involved area
• Treat tinea pedis, toe maceration (strep) if present
• Consideration of concurrent oral steroid treatment to decrease post- inflammatory lymphatic damage; more studies needed
• For hospitalized patients: empiric therapy for MRSA should be considered
• Cultures from abscesses and other purulent skin and soft tissue infections (SSTIs) are recommended in patients to be treated with antibiotic therapy but if case has a typical presentation, they need not be performed |
| What are MRSA risk factors? | • Healthcare-associated MRSA (HA-MRSA) and community-associated MRSA (CA- MRSA) risk factors include:
. Antibiotic use
•Prolonged hospitalization
•Surgical site infection
•Intensive care
•Hemodialysis
•MRSA colonization
• Proximity to others with MRSA colonization or infection
• Skin trauma
• Cosmetic body shaving
• Group facilities
• Sharing equipment that is not cleaned or laundered between users/body contact as in sports |
| What is erysipelas? | • Erysipelas is a superficial cellulitis with marked dermal lymphatic involvement (causing the skin to be edematous or raised) Main pathogen is group A streptococcus
• Also caused by Staph aureus, Haemophilus, and others
• Usually affects the lower extremities and face
• Presents with pain, bright erythema, and plaque-like edema with a sharply defined margin to normal tissue
• Plaques may develop overlying blisters (bullae)
• May be associated with a high white count (>20,000/mcL)
• May be preceded by chills, fever, headache, vomiting, and joint pain |
| How is appearance of erysipelas? | • Dermo-hypodermal bacterial acute non necrotizing infection of the legs or face
• Predominantly on the lower limbs in 85% of cases
• The incidence of the disease is increasing in industrialized countries
• The average age of affected individuals is 60 years, the sex ratio of 1
• Large, shiny erythematous plaque with sharply demarcated borders located on the leg |
| What is tx of erysipelas? | • Immediate empiric antibiotic therapy should be
started (cover most common pathogen - Streptococcus) Such as penicillin V, amoxicillin, clindamycin, macrolide, and others
• Monitor patients closely and watch the therapy if
there is a poor response to initial treatment
• Elevation of the involved area
• Treat tinea pedis, erythrasma, or intertrigo |
