4/16/2013

1

Complicated Skin and Soft Tissue Infectiondiagnosis and severity stratification

Muhammad Hussein GasemDiv Infectious Disease, TropMed, and Immunology

Dr. Kariadi Hospital, Diponegoro UniversitySemarang, Indonesia

Clinical DiagnosisInvolvement in skin and soft-tissue infections

RAJAN S Cleveland Clinic Journal of Medicine 2012;79:57-66

Ecthyma

Anatomical structure Infection Epithelium Varicella, Measles

Keratin layer Ringworm

Epidermis Impetigo

Dermis Erysipelas

Hair follicles Folliculitis, boils, carbuncles

Sebum glands Acne

Deeper dermis, subcutaneous fat Cellulitis

Fascia Necrotizing fasciitis

Muscle Myositis, Gangrene

Types of infection affecting skin and soft tissues structure

Dryden MS J Antimicrob Chemother 2010; 65 Suppl 3: iii35–44(with modification)

4/16/2013

2

Clinical diagnosis

§Specific clinical appearance of infected skin & soft tissues might useful in guiding empirical antibiotic treatment.

§Some clinical pictures are not specific, therefore it can be misdiagnosed and treated by antibiotics irrationally

Celulitis Erysipelas

Classification of SSTIs #)

UNCOMPLICATED

§Superficial infections- Simple abscesses- Impetigo- Folliculitis- Ecthyma- Furunculosis/carbunculosis- Cellulitis

§Can be treated by incision-drainage only

COMPLICATED (cSSTIs) / severe SSTI

§Deep soft tissue infections-Necrotizing fasciitis (NSTI)-Complicated surgical site infection

§Requires significant surgical intervention- Infected ulcers- Infected burns- Major abscesses

§Significant underlying disease state,which complicate response to treatmentf.i. diabetic foot infection (DFI)

#) FDA classification with modification

1. Gram-positive aerobes-Staphylococcus aureus(MSSA, HA-MRSA, CA-MRSA)

-Coagulase-negative Staphylococci-Streptococcus (group A & B)-Enterococcus etc.

2. Gram-negative aerobes-Enterobacteriaceae-Pseudomonas aeruginosa etc.

3. Anaerobes-Bacteriodes fragilis & group isolates -Fusobacterium-Anaerobic Streptococci etc.

Causative organisms of SSTIs *)

*) monomicrobial or polymicrobial infections

4/16/2013

3

Most common types of monomicrobial SSTIs

Hau T, European J Clin Microb Infect Dis, 2002

Causative organism Type of infectionStaphylococcus aureus §Impetigo & bullous skin infections

§Folliculitis, furuncle, carbuncle§Suppurative hidradenitis§Subcutaneus abscesses

Streptococcus spp. §Cellulitis§Erysipelas§Ecthyma§Streptococcal gangrene

Subcutaneus abscess

Polymicrobial 48 %

Complicated skin & soft tissue infectionsa broad range of causative pathogensincluding patients with diabetic foot infection

Giordano, et al. Int J Antimicrob Agents. 2005 Nov;26(5):357-65n = 237 (number of patients with respective pathogen)

Petrostreptococci 8 %

Staphylococcus aureus 52 %

Non-group A beta hem Strep 21 %

E. faecalis 13 %

Streptococcus pyogenes 13 %

E. coli 8 %

Pseudomonas sp 6 %

0 10 20 30 40 50 60

Polymicrobial 48%

2 isolates: E. coli & methicillin-susceptible S. aureuswere cultured from superficial sample

Case: Mrs N, 43 yrs, T2DMwith chronic diabetic foot ulcer.Wound specimens were takenon admission day.

Alcaligenes faecaliswas cultured from deep-site sample

Dr. Kariadi Hospital, SmgDr. Kariadi Hospital, Smg

4/16/2013

4

Risk factor Characteristic pathogens

Recurrent hospital admissions MRSA

Contact sports, recurrent boils, abscesses

MRSA or MSSA producing PVL

Diabetes mellitus S. aureus (MRSA and MSSA), Group β-haemolytic, Gram-negative bacilli

Neutropenia Gram-negative bacilli, P. aeruginosa

Bite woundshumancatdograt

Human oral floraPasteurella multocidaCapnocytophaga canimorsusStreptobacillus moniliformis

Animal contact Campylobacter spp, Bartonella henselaeFrancisella tularensis, Bacillus anthracisYersinia pestis

Risk factor for SSTIs caused by specific pathogens (1)

Dryden MS. J Antimicrob Chemother 2010; 65 Suppl 3: iii35–44

Risk factor Characteristic pathogens

Water exposure (sea, rivers) Vibrio sppAeromonas hydrophiliaMycobaterium marinumP. aeruginosa

Reptile contact Salmonella spp

Injecting drug use MRSAClostridium botulinumClostridium tetani

Travel LeishmanasisCutaneous larva migransMyiasis

Risk factor for SSTIs caused by specific pathogens (2)

Dryden MS J Antimicrob Chemother 2010; 65 Suppl 3: iii35–44

Category Clinical features

Class 1 SSTI but no signs or symptoms of systemic toxicity or co-morbidities

Class 2 Either systemically unwell or systemically well but with co-morbidity (e.g diabetes) that may complicate or delay resolution

Class 3 Toxic and unwell (fever, tachycardia, tachypnoea and/or hypotension)

Class 4 Sepsis syndrome and life-threatening infection (e.g necrotizing fasciitis)

Classification of SSTI according to the severity of local and systemic signs

Eron LJ et al. J Antimicrob Chemother 2003; 52 Suppl 1: i3–17.

4/16/2013

5

Category Clinical features

Class 1 Drainage (if required) and oral antibiotics as outpatient

Class 2 Oral or outpatient parenteral antibiotic therapy (OPAT); may require short period of observation in hospital

Class 3 Require inpatient treatment with parenteral antibiotics

Class 4 Admit to hospital/ICU, urgent surgical assessment and treatment with parenteral antibiotics

Management of SSTI according to grading of severity

Eron LJ et al. J Antimicrob Chemother 2003; 52 Suppl 1: i3–17.

Initial assessment and classification

Class 1 Class 4Class 2 Class 3

Consider observation status

Send home onoral antimicrobial

therapy

Admit tohospital

OPAT

Consider oral switch therapy

Discontinue antimicrobial therapy

Discharge

Suspected SSTI

Any ONE of the following symptoms :Temperature < 350C or > 400C, Hypotension, HR >100 beats/min, altered status

Head and/or hand involvement, orSize of lesion > 9% body surface area

Any ONE of the following signs symptoms :Bullae, Rapidly progressive, Hemorrhage, Crepitus, Severe pain

Any ONE of the following comorbidities :Chronic liver/renal dx, Vascular indufficiency, Asplenia, Immunocompromise

No

No

No

No

Yes

If Yes

MILD SEVERE

Evaluation algorithm for severity of SSTIs

4/16/2013

6

Diagnostic tests

Plain radiography: gas or periostal inflammation (DFI)

USG: detect abscesses

MRI and CT: image fascial planes (Necrotizing fasciitis)

Laboratory tests: CRP, WBC, Hb, Creatinin, Na, Glucose (LRINEC)

Clinical Manifestation of Infection Infection Severity PEDIS GradeWound lacking purulence or any manifestations of inflammation

Uninfected 1

Presence of ≥ 2 manifestations of inflammation Any cellulitis/ erythema extends ≤ 2 cm around the ulcer Infection limited to the skin or superficial subcutaneous tissuesNo other local complications or systemic illness

Mild 2

Patient is systemically well and metabolically stable ≥ 1 of the following characteristics :

Cellulitis extending > 2 smLymphangitic streakingSpread beneath the superficial fasciaDeep-tissue abscessGangreneInvolvement of muscle, tendon, joint, or bone

Moderate 3

Infection in a patient with systemic toxicity or metabolic instability

Severe 4

Lipsky BA, Barendt AR, Deery HG, et al. Clin Infect Dis 2004;39:885-910Abbreviation : PEDIS: Perfusion, Extent/size, Depth/tissue loss, Infection, and Sensation

Risk stratification for patients with Diabetic Foot Infections

Diabetic foot infection

Case 1: PEDIS grade 3 Case 2: PEDIS grade 4 with systemic signs (sepsis)

4/16/2013

7

Necrotizing Soft Tissue Infections

Early presentation of NSTI may not be recognized, with few skin signs

Diagnosis should be suspected in patients whose pain and toxicity appear to be out of proportion to clinical findings

Diagnosis is based on the clinical picture and should not be delayed while waiting for test results

Treatment are resuscitation, aggressive surgical debridement, and empiric broad-spectrum intravenous antibiotics

Mortality is high, and increase with delayed diagnosis and treatment

Risk factors for Necrotizing Soft Tissue Infections§Diabetes mellitus§ Chronic disease§ Immunosuppressive drugs §Malnutrition§ Age > 60 years§ Intravenous drug misuse§ Peripheral vascular disease§Underlying malignancy§Obesity

Skin Pain General

Erythematic with ill-defines margins

Tense edema with grayish or brown discharge

Lack of lymphangitis or lymphadenopathy

Vesicles or bullae, hemorrhagic bullae

Necrosis, crepitus

Pain that extends past margin of apparent infection

Severe pain that appears disproportionate to physical finding

Decreased pain or anesthesia at apparent site of infection

Fever with toxic appearance

Altered mental state

Tachycardia

Tachypnea due to acidosis

Presentation with DKA or HHNK

Clinical features suggestive severe SSTI : Necrotizing Soft Tissue Infections (NSTI)

DKA-diabetic ketoacidosis, HHNK-hyperosmolar hyperglycemic non-ketotic acidosis Puvanendran R et al Can Fam Physician 2009

Early recognition of NSTI orDistinguishing NSTI from other severe SSTIs

is often difficult clinically à need a diagnostic scoring system

based on laboratory tests

4/16/2013

8

Investigation Score

Serum C-reactive protein > 150 mg/L 4 points

White blood cell count� 15.000/µL – 25.000/µL� > 25.000/µL

1 point2 points

Hemoglobin � 11.0 – 13.5 g/dL� < 11 g/dL

1 point2 points

Serum sodium < 135 mEq/dL 2 points

Serum creatinine > 1.6 mg/dL {141 mmol/L} 2 points

Serum glucose > 180 mg/dL {10 mmol/L} 1 point

Laboratory risk indicator for Necrotizing Fasciitis (LRINEC score):

Puvanendran R et al Can Fam Physician 2009;55:981-7Napolitano LMInfect Dis Clin N Am 23 (2009) 571–591

≤5 points indicated a low risk (< 50% probability) of NF≤6-7 points indicate on intermediate risk (50%-70% probability) of NF ≥8 points indicate a high risk (>75% probability) of NF

Terimakasih