Common cutaneous bacterial infections
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Transcript Common cutaneous bacterial infections
Common cutaneous bacterial
infections
Faghihi. G.
Dermatology professor
Isfahan University of Med.
Normal skin is a barrier against
microbial pathogens
Predisposing factors to
Bacterial Skin Infections :
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Neutropenia
HIV infection
IV Drug ABUSE
Diabetes
Parasitic Infestations
Wounds,burns,abrasions
Atopic disease
Alcoholism
MRSA Abscess and Surrounding
Cellulitis in Arm of Patient with HIV
Infection
Some other conditions as risk
factors for bacterial cut. Infections
For example :
poor hygiene
friction and wearing
tight clothing
seborrhea
Common important bacterial skin
infections
Include:
• Impetigo
• folliculitis
• furuncles
• carbuncles
• cellulitis
• erysipelas
Impetigo
pustules or bullae
that rupture and
become crusted
usually appears on
the face, especially
around nose and
mouth
mainly affects
infants and children
• The infection is spread by direct contact with
lesions or with nasal carriers.
• The incubation period is 1–3 days after
exposure to Streptococcus and 4–10 days for
Staphylococcus
The most common pathogen
Both bullous and nonbullous are primarily
caused by Staphylococcus aureus
with Streptococcus also commonly being
involved in the nonbullous form.
Risk factors for Impetigo
Atopic dermatitis
parasitosis
Trauma
Burns
minor abrasions
Sports(direct
contact)
Diagnosis usually clinically
smear and culture
definitely
• Leucocytosis …..
About 50 % patients
Children who get impetigo:
should not attend school or daycare.
They should not have close contact, with other
children
limited uncomplicated impetigo
Treatment(topical):
• Ointment mupirocin
• Ointment retapamulin
• Cream fusidic acid
Equally as effective as oral Ab.
Extensive or accompanied systemic
symptoms or lymphangitis(systemic Ab.)
• Penicillins( dicloxacillin, flucloxacillin or
Alternatively amoxicillin combined with
clavulanate
• Cephalosporins
• Clindamycin
• Macrolids
In cases of severely ill/ immunocompromised
• IV ceftriaxone
• Iv ampicillin/sulbactam/cefuroxime
One major complication of impetigo:
• Post Strep GN
Efficacy of treatment of strep.impetigo
is not known.
In eradication acute P-S-G-N
MRSA decolonization
Impetigo Bockhart
superifical staphyloccocal folliculitis
a superifical staphyloccocal
folliculitis with thin-walled pustules
at the folliclular openings.
Streptococcal
intertrigo
is a cutaneous condition
seen in infants and young
children, characterized by
a fiery-red erythema and
maceration in the neck,
axillae or inguinal folds
a distinctive foul odor and
an absence of satellite
lesions.
Treatment strep.intertrigo
eliminate friction, heat,
and maceration by keeping folds cool
and dry
Compresses with
Burow solution
1:40
Treatment with penicillin V-K
suspension, 125 mg orally 3 times a
day 10 days
Bacterial folliculitis
The bacterial agent often
responsible for folliculitis
is Staphylococcus aureus
The infection (hair
follicles)can be shallow
or deep
can even lead to
formation of
inflammatory nodules or
pustules
which will surround the
hair follicle.
• superficial folliculitis (the most
common form)
• Deep folliculitis (sycosis)
Folliculitis most commonly
occurs://
• Beard area in men
• Scalp
• Upper trunk (chest, under
breasts, in armpits)
• Buttocks
• Thighs
• Groin
Pseudomonas aeruginosa
folliculitis
• hot tub folliculitis
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The infection is typically found in
areas of the body, which are
soaked under an improperly
chlorinated hot tub or wirlpools.
• The typical body parts affected
::are buttocks, hips, legs and
thighs ,face and neck are spared.
It is self limited(7-14 Days)
• Sometimes for widespread
infection or immunosuppressed or
febrile ,ill patients:
oral quinolone/topical gentamycin
Folliculitis Treatment
• Superficial folliculitis may heal on its own within 1 to 2 weeks
Applying antibiotic ointments like Bacitracin, (bacitracin +
neomycin + polymyxin B), or (mupirocin), washing with
antibacterial soaps may help in more resistant cases
• In a deep folliculitis and recurrent cases, oral antibiotics (dicloxacillin,
cephalosporins) may be needed.
• Folliculitis caused by MRSA requires treatment by antibiotics chosen on the
basis of antibiotic sensitivity test (1).
• S. aureus carriers may be treated with mupirocin ointment in the
nasal vestibule as previously said...
Family members may be also treated by mupirocin to eliminate the carrier state and
prevent re-infection
(boil ) furuncle
Furuncles are skin
abscesses caused by
staphylococcal
infection, which involve
a hair follicle and
surrounding tissue.
A carbuncle
is a coalescence of several
inflamed follicles into a
single inflammatory mass
with purulent drainage
from multiple follicles.
Constitutional symptoms,
including fever and
malaise, are commonly
associated with these
lesions but are rarely
found with furuncles.
Diff Dx furuncles or carbuncles
• Ruptured epidermal cysts or pilar cysts
• Acne conglobata
• Hidradenitis suppur.
Patients with recurrent
furunculosis
should be evaluated:
predisposing factors such as
obesity,
diabetes,
occupational or industrial exposure
to inciting factors,
nasal carriage of Staphylococcus
aureus or ,/methicillin-resistant S.
aureus (MRSA) colonization.
Furuncles treat./
• Treatment with warm compresses antiseptic sol./
or incision and drainage
• Systemic antibiotics:(multiple furuncles,severe
illness, systemic signs, immunosuppresed ,
cellulitis around lesions , Areas like nose, Ear
canal ,face and genitalia and acral parts:
• Cloxacillin,dicloxacillin,CA-MRSA: (Cotrimoxazole ,
doxy, clinda )
Bacterial cellulitis
Cellulitis is a deep infection of the skin, (dermis/
subcutis) usually accompanied by generalized
(systemic) symptoms such as fever and chills.
streptococci , Staphylococcus and
H.influenza, are the most common
causes of cellulitis.
Cellulitis causes the affected area of skin to
turn red, painful, hot and swollen
Risk factors for cellulitis
• a skin condition such as eczema or a fungal infection of the foot
or toenails (athlete’s foot) can cause small breaks to develop in
the surface of the skin.
• having a weakened immune system (as a result of health
conditions such as HIV or diabetes, or as a side effect of a
treatment such as chemotherapy
• lymphoedema – a condition that causes swelling of the arms
and legs, which can sometimes occur spontaneously or may
develop after surgery for some types of cancer
• Venous insufficiency
• intravenous drug abuse (injecting drugs such as heroin)
Cellulitis secondary to tinea infection.
Venous Insufficiency With Supra-Imposed
Ulceration and Severe Cellulitis
In healthy adults
isolation of an etiologic agent is difficult and
unnecessary.
If the patient has:
diabetes, an immunocompromising disease, or
persistent inflammation:
blood cultures or aspiration of the area of
maximal inflammation may be useful.
Indications for IV antibiotics in cellulitis
• Severely ill patients
• those whose condition is unresponsive to
standard oral antibiotic therapy
• Immunosuppressed patients
• Patients with facial cellulitis
• Any patient with a clinically significant
concurrent condition, including lymphedema
and cardiac, hepatic, or renal failure
• Individuals with newly elevated creatinine,
creatine phosphokinase, and/or low serum
bicarbonate levels or marked left-shift
polymorphonuclear neutrophils
In cases of cellulitis without draining wounds or
abscess,
• streptococci continue to be the likely etiology,
and beta-lactam antibiotics are appropriate therapy, as noted in the
following:
In mild cases of cellulitis treated on an outpatient basis, dicloxacillin,
amoxicillin, and cephalexin are all reasonable choices
Clindamycin or a macrolide (clarithromycin or
azithromycin) are reasonable alternatives in patients who are allergic to
penicillin
fluoroquinolones are best reserved for gram-negative organisms with
sensitivity demonstrated by culture
Some clinicians prefer an initial dose of parenteral antibiotic with a
long half-life (eg, ceftriaxone followed by an oral agent)
In otherwise healthy adults
empiric treatment with
a penicillinase-resistant
penicillin,
first-generation
cephalosporin,
amoxicillin-clavulanate
(Augmentin),
macrolide, or
fluoroquinolone (adults only)
is appropriate.
Antibiotics should be maintained for at least
three days after the resolution of acute
inflammation
Adjunctive therapy includes:
• cool compresses;
• appropriate analgesics for pain;
• tetanus immunization; and
• immobilization and elevation of the affected
extremity
more severe cases that require
parenteral antibiotics to cover MRSA
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, vancomycin,
daptomycin,
tigecycline,
ceftaroline, and
linezolid are appropriate choices.
However, vancomycin continues to be the drug of
choice because of its overall excellent tolerability
profile, efficacy, and cost
Erysipelas
an acute streptococcus bacterial
infection of the upper dermis and
superficial lymphatics.
Historically, the face was
most affected; today the legs
are affected most often
The erythematous skin lesion
enlarges rapidly and has a
sharply demarcated
raised edge.
It appears as a red,
swollen, warm,
hardened and painful
rash, similar in
consistency to an
orange peel. More
severe infections can
result in vesicles,
bullae, and
petechiae, with
possible skin
necrosis.
Blood cultures are unreliable for diagnosis of
the disease, but may be used to test for
sepsis.
Elevation of (ASO) titer occurs after around 10 days
of illness.
Erysipelas must be differentiated from:
herpes zoster,
angioedema,
contact dermatitis, and
diffuse inflammatory carcinoma of the breast.
ERYSIPELOID
Acute cut,. infection
with Erysipelothrix
rhusiopathiae.
This type of bacteria is
found in
fish, birds, mammals,
and shellfish.
It usually affects
people who work with
these animals (such
asfishermen , farmers
or butchers).
Symptoms
warmth, tenderness, and
redness
(non purulant cellulitis)on
the skin
Treatment
Antibiotics, especially
penicillin, are used to
treat
alternatives:
erythromycin
cephalosporine
tetracyclines
The infection rarely spreads. It may be
self limited.
ERYTHRASMA
Chronic superficial bacterial skin infection
Corynebacterium Minutissimum
inside startum corneum
Wood light examination of
erythrasma
The patches of erythrasma are initially
pink, but progress quickly to become
brown and scaly (as skin starts to shed),
which are classically sharply demarcated.
Erythrasmic patches are typically found in
intertriginous areas (skin fold areas - e.g.
armpit, groin, under breast) - with the toe
web-spaces being most commonly
involved.
The patient is commonly otherwise
asymptomatic.
The diagnosis can be made on the clinical
picture alone.
It is prevalent among diabetics and the
obese,
and in warm climates;
it is worsened by wearing occlusive
clothes.
Treatment of erythrasma
Aluminium chloride 20%
improved hygiene
topical azoles
topical fusidic acid
oint. whitefield(SA +Bezoic acid)
oral erythromycin or
tetracyclines
موفق باشید
erythrasma