Dr. Juhaina Al-Moosawi

Mentor :

Dr. Salma Al-Mauwali

Introduction :

Soft tissue infection :

A group of disease that involve the skin

, S/C , fascia or muscle .

Localized / involve a large portion .

Harmless if treated / life threatening

even when appropriately treated .

Classification :

• Localized/ superfecial infections

Cellulitis

Abscess

Impetigo

• Lethal infections

Toxic shock syndrome

Necrotizing fasciitis

Myonecrosis

Superficial

Deep

Cellulitis :

A soft tissue infection of the

skin & S/C .

Risk Factors :

• H/O trauma

• Skin injury .

• Underlying disease

(diabetes , impaired lymphatic drainage )

Clinical Feature :

• Pain

• Tenderness

• Erythema

• Swelling of the involved area

• Local warmth

Causes :

• Streptococcus pyogenes .

• Staphylococcus aureus.

Diagnosis :

• Clinical manifestations .

• Fever is uncommon .

• No workup in the following criteria:

Small area of involvement

Minimal pain

No systemic signs of illness

(fever, dehydration, altered mental status, tachypnea, tachycardia, hypotension) .

No risk factors for serious illness .

workup in serious cases :

• CBC

• U&E

• Blood cultures

• Aspiration of the wound

+ ve collection .

Imaging Studies :

• Plain XR unnecessary in

uncomplicated cases.

• Soft tissue XR or U/S :

purulent material or foreing body.

U/S guided aspiration of pus :

shorten hospital stay .

Antibiotic

AnalgesiaWarm packs

Elevation

Immobilization

Management

Disposition :

Cellulitis

In patientOut patient

Localized

No fever

Oral antibiotic

F/U 24-48 h

Increase erythematus area

Fever

Systemic symptoms

Systemic toxicity

Sever infection :

Hand , feet ,head ,

Neck , perineum .

Worsen cellulitis

48-72 h .

Immunocompramised

Paranteral antibiotic

Oral Therapy of Superficial Soft Tissue infection :

Agent Dose

Group A Streptococcus

Penicillin V ( phenoxymethylpenicillin)

First generation cephalosporin

Erythromycin

Azithromycin

Clarithromycin

Staphylococcus aureus ( not MRSA )

Dicloxacillin

generation cephalosporin

First

Cloxacillin

Erythromycin ( variable effectiveness )

Azithromycin

250 -500 mg qid

250 -500 mg qid

250 -500 mg qid

500 mg x 1 dose

Then 250 mg qd x 4

500 mg bid

125 -500 mg qid

250 - 500 mg qid

250 – 500 mg qid

250 – 500 mg qid

Then 250 mg qd x4

500 mg x 1 dose

Agent Dose

Clarithromycin

Clindamycin

Amoxicillin / clavulanate

Ciprofloxacin

Haemophilus influenzae

Amoxicillin / clavulanate

Cefactor

Trimethoprin (TMP)/sulfamethazone

(SMX)

Azithromycin

Clarithromycin

500 mg bid

150 -450 mg qid

875/125 mg bid

Or 500/125 mg tid

500 mg bid

250-500 mg tid

250-500 mg tid

160 mg TMP/800 mg

smx bid

500 mg x 1 dose

Then 250 mg qdx4

500 mg bid

Emergency Department Protocol for

the Management of Cellulitis , Nova

Scotia, Canad

Cellulitis :

Acute spreading inflammation

involving the soft tissue,

excluding muscle, characterized

by recent onset soft-tissue

erythema, warmth, swelling &

tenderness, considered to be of

infective origin, and acquired in

the community.

Department of Emergncy Medcine * and Pharmacy ^ Dalhousie University Halifax,

Nova Scotia, Canad

Journal of Emergency Primary Health Care (JEPHC)

• Excluded infected surgical wounds

or previously treated (< 3 months)

deep diabetic infections.

Cellulitis Grading scale :Grade Clinical features

I Symptoms/signs restricted to superficial swelling, erythema, warmth, mild

lymphadenopathy, & mild pain; absence of systemic symptoms in patients

without risk factors for poor outcome .

II dominant systemic signs – fever, chills lymphangitis &/or rapidly advancing

edge.

mild cellulitis (as defined in grade I) in high-risk, non-neutropenic, splenic

patients.

III severe facial, perineal or extensive skin involvement (i.e. if any dimension of

the area of skin involved is greater than the distance between the patient’s

median wrist and the point of the elbow).

failure to respond to >48 hrs of adequate oral Rx,

a history of episodes of cellulitis requiring prolonged intravenous therapy.

IV deep perineal, orbital, joint, or deep hand involvement.

cellulitis in neutropenic or asplenic patients.

suspicion of necrotizing, deep-seated infection or severe sepsis .

Infected bite

Diagnosis

of

Cellulitis1

Suspicion of

Abscess ? Appropriate

surgical

management.

Avoid antibiotics

unless surrounding

area of cellulitis.

Use the same grading

system for disposition, but

use Table I for antibiotic

choice.

Consider the possibility of

necrotizing infection ? Yes

NO

Grade IVGrade III Grade I Grade II

Cellulitis algorithm

NO

Grade I Grade II Grade IVGrade III

Immediately give

Clindamycin 900mg IV

and Ceftriaxone 2g IV

and IMMEDIATE

REFERRAL

IMMEDIATE

CONSULTS:

I.D. for all patients

plus:

Necrotizing

infection– surgery,

Deep hand

infection– Plastic

Surg.

Orbital cellulitis–

Opthalmology.5

Candidate for

home IV therapy4

NOYes

Cefazolin or

Cloxacillin

1-2g IV2,3

Probenecid 2g

po & Cefazolin

1-2g IV2,3

Refer for

admission

Closely supervised

home therapy.

Probenecid 2g po &

Cefazolin 1g IV q24

hrs. Change to P.O.

regimen as for Grade I,

if Grade I features

obtained for > 24 hrs.

Reassessment by FP

in 5 days.

Initial dose of Probenecid

2g po & Cefazolin 1-2g 2,3

Cephalexin 500 mg

QID po x 7 days.

or, Cloxacillin 500mg

QID po x 7 days

or, Azithromycin

500 mg po followed by

250 mg/day x 4 days.

Family doctor

and reliable

patient/family

NOYes

Return to ED

in 24-36h if

no

improvement

Follow-

up with

FP in

24-36h

Cephalexin 500

mg QID po x 7

days or,

Cloxacillin 500mg

QID po x 7 days

or, Azithromycin

500 mg po

followed by 250

mg/day x 4 days.

Family doctor

and reliable

patient/family

NOYes

Return

to ED in

36-48h if

no

improve

ment

Follo

w-up

with

FP in

48-

72h

Yes

probenecid

• Inhibit renal tubular

reabsorption of uric acid which

lower serum uric acid levels.

• It is recommended for patients

with gout.

• Increase & prolong the serum

level of the antibiotic.

Studies suggest that intravenous cefazolin 2

g and oral probenecid 2 g daily is an

effective regimen in the treatment of SSTI.

The Annals of Pharmacotherapy , 23 January 2004

Toxic shock syndrome

(TSS)

A shock syndrome caused by the

inflammatory response to toxins produced

by various bacteria .

Types of Toxic Shock

Syndrome

• Staphylococcus bacteria

(TSS).

• Group A Streptococcus bacteria

(STSS)

Epidemiology :

• Discovered in 1978 in 7 children aged 8-17 years who had

shock from Staphylococcus aureus .

• The peak incidence of TSS occurred in 1980 associated with

increased vaginal tampons use in menstruating women

~ 2.4 – 16 cases / 100,000 population .

• CDC reported 200 cases / year from 1994 – 2001 with a steady

increase in strep TSS & decrease in incidence of staph TSS since highly absorbent tampons were withdrawn from the market .

• Strept TSS was 1st described in 1987 when reported 2 cases of

shock due to isolated Step.Pyogenes .

• TSS remains as highly fatal disease with mortality rate 30%-70%.

Principles of disease

Staph . aureus Strep . pyrogenic

toxin

( TSST-1)

entertoxine

B

SPEA SPEB

exotoxin

BloodMononuclear

cells

IL TNF

cytokines

System

PATHOPHYSIOLOGY TSS:

3 phases:

1. Growth and multiplication of the

bacteria.

2. Production of the toxin.

3. Activation of the immune system.

PHASE 1

Menstrual blood enhances

the growth of S.aureus

by providing a growth

medium for the micro-

organism.

The tampons contain

fibres that inhibit the

lactobacilli & diminish

their ability to limit the

growth of S.aureus.

PHASE 2 ; TOXIN PRODUCTION

1. High protein levels

2. Neutral pH

3. High oxygen levels

• Menstrual blood increases the protein levels and provides a neutral pH which provides excellent conditions for toxin production.

• Tampons helps in introducing oxygen into the vagina also increasing toxin production.

• Tampons cause microtrauma and increase the risk of the exposure of the toxins to the blood..

Phase 3

superantigen toxin

MHC II + T cell

polyclonal T cell activation.

• cytokine storm

• TNF, (IL)

www.AMDTelemedicine.com

TSS Criteria for diagnosis

Fever of 38.9 c ( 102 F) or higher .

Rash ( diffuse macular erythema )that resembles the rash of scarlet fever

Desquamation of skin 1-2 weeks after onset of disease .

Hypotension ( syst BP less than 90 mm Hg , orthostatic drop of 15 mm Hg

or more or orthostatic dysness or syncope ) .

Clinical or lab abnormalities in at least 3 organ system :

GI : Nausea , vomiting , diarrhea .

Muscular : myalgia , creatine phosphokinase x 2 times normal .

Mucous membrane : vaginal oropharyngeal , conjunctival hyperemia .

Renal : Blood urea , creat X 2 times normal level , pyuria greater than 5

cells / high power field .

Hepatic : bilirubin , serum transaminases x 2 normal level .

Hematologic : thrombocytopenia , less than 100,000/mm3 .

Neurologic : disorientation or altered consciousness without focal

findings

Reasonable evidance for the absence of other cause of illness .

Definition of Streptococcal Toxic

Shock Syndrom

Must meet criteria from both 1 & 2 below :

1. Isolation of group A Streptococcus from :

a. A normally sterile site such as blood or CSF is a definite cases.

b. A normally nonsteriel site such as sputum or skin lesion is a

probable case .

2. Hypotension & at least 2 of the following :

a. Renal impairment .

b. Coagulopathy .

c. Liver involvement .

d. Adult respitarory distress syndrome .

e. Generallized erythematous macular rash that may desquamate

f. Soft tissue necrosis .

Comparison of Staphylococcal &

Strptococcal TSS:Feature Staphylococcal Streptococcal

Age Primarily 15-35 yr 20-50 yr

Sex Greatest in woman Either

Sever pain Rare Common

Hypotension 100% 100%

Erythroderma rash Very common Less common

Renal failure Common Common

Bacteremia Low 60%

Tissue necrosis Rare Common

Predisposing facto Tampons ,paking , Cut , burns

,Bruises ,

Varicella ,

NSAID use ?

Thrombocytopenia Common Common

Mortality rate less 3% 30%-70%

Risk Factors for Toxic Shock

SyndromeUse of superabsorbent tampons .

Post operative wound infections .

Post partum period .

Nasal paking .

Common bacterial infection .

Infection with influanza A .

Infection with varicella .

Diabetes mellitus .

Human immunodeficiency virus infection .

Chronic cardiac disease .

Chronic pulmonary disease .

Nonsteroidal anti inflammatory use ( may mask symptoms rather than

be a risk factor )

Complication :

• ARDS .

• SHOCK .

• Gangrene .

• Disseminated

intravascular

coagulation

(DIC ).

• Renal failure

DXD :

• Rocky mountain spoted fever .

• Streptococcal scarlet fever .

• Staphylococcal scalded-skin syndrome .

• Kawasaki syndrome .

• Leptospirosis .

• Viral illnesses

Managment :

• Aggressive IV fluid resuscitation .

• O2

• Removal of source of bacteria .

• Early antibiotic :

Recommended in strept TSS

Clindamycine : 600-900 mg IV x8h

• Wound debridement .

• Hyperbaric oxygen therapy .

• Vasopressor .

• Immunoglobulin IV 400 mg/ Kg .

• Corticosteroids if pt suspected of having Adrenal insufficiency related to underlying disease or chronic steroid use .

Necrotizing fasciitis

Progressive, rapidly spreading,

inflammatory infection located in

the deep fascia, with secondary

necrosis of the s/c .

• 1989 toxic shock syndrome and strep A

necrotizing fasciitis reported.

• The overall morbidity and mortality is 70-

80%.

• Strep NF is frequently associated with

STSS .

• A retrospective study showed that upper extremity necrotizing fasciitis has a high mortality rate.

• In their review, about 35% of patients died.

• A state of altered consciousness and respiratory distress at initial presentation were found to be statistically significant factors for eventual mortality

emedicine.medscape.com Mar 25, 2009

Michael Maynor, MD, Clinical Assistant Professor, Department of Hyperbaric/Emergency Medicine, Louisiana State University School

of Medicine

Types :

• Type I NF

Polymicrobial infection :

anaerobes , non-group A Strep.

• Type II NF

Monomicrobial infection :

group A beta hemolytic Strep

Clinical Features :

Stages of NF progression

• I (Early)

Erythematus /warmth

Tenderness

Edema

Fever

• II (Intermediate)

• Bullae formation

• Necrotic patches

• Oozing

• III (Late)

Crepitus

Skin anesthesia

Sever systemic reaction .

Risk factor :

• Surgical procedures

• ( intraperitoneal infections and

drainage perianal abscesses ).

• IM injections and IV infusions .

• Insect bites .

• Local ischemia and hypoxia

(e.g., diabetes).

• Alcoholics.

• NSAIDs .

Diagnosis :

• CBC

• U&E

• Ca

• Blood c/s : +ve in GAS

• Deep sample biopsy

• Local XR : presence of gas

• MRI differentiated between acute cellulitis from NF .

A risk score retrospectively devised in six

common laboratory parameters :

• CRP ≥150 mg/L (4 points) .

• WBC 15,000 to 25,000/microL (1 point) or >25,000/microL (2 points) .

• HGB 11.0 to 13.5 g/dL (1 point) or ≤11 g/dL (2 points) .

• Na < 135 meq/L (2 points) .

• Creatinine > 1.6 mg/dL (141 mmol/L) (2 points).

• Serum glucose > 180 mg/dL (10mmol/L) (1point).

Uptodate 2009

• A total score ≥6 should raise the suspicion

for necrotizing fasciitis ( 7-10%).

• score ≥8 was highly predictive (>75 %).

• The score is only useful when severe soft

tissue infection is strongly suspected.

Mangmnat :

• Surgical debridement .

• fluid resuscitation .

• Antibiotic therapy :

Type I :

• ampicillin + clindamycin / metronidazole.

Type II :

• Clindamycin + penicillin .

Uptodate 2009

Conclusion:

Rapid identification and rapid

treatment is essential for

recovery from aggressive

disease.