31 terms

Skin & Soft Tissue Infections

Cellulitis Facts
Acute spreading "nonnecrotizing infection affecting the dermis and subcutaneous tissue but does not involve the deep fascia or muscles. May mimic DVT. Often associated with fever, chills, and leukocytosis.
Cellulitis pathogens
Streptococcus pyogenes and/or S. aureus.
Children: H. influenzae possible
Celluitis Treatment
Healthy outpatient: Dicloxicillin, oral cephalasporin, clindamycin, erythromycin, azithromycin, clarithromycin, amxoicillin-clavulanate

IV: clindamycin, vancomycin, cefazolin, nafcillin, or oxacillin
Erysipelas Facts
Superficial skin infection, usually lower extremities or face, involving lymphatics. Bright red and painful indurated lesion with sharply demarcated border
Erysipelas pathogen
Group A streptococci, rarely S. aureus
Erysipelas Treatment
NonDM: Penicillin G
DM: Nafcillin, oxacillin, ceftriaxone, amoxicillin-clavulanate
Impetigo Contagiosa Facts
Superficial, vesiculopustular lesion, contagious, usually children. Small, fluid-filled vesicles, pus-filled blisters.
Impetigo Contagiosa Treatment
Oral cephalasporin
Bollous Impetigo Facts
Starts as vesicles that turn into flaccid bullae containing clear yellow fluid
Bollous Impetigo Pathogen
S. aureus
Bollous Impetigo Treatment
Lymphangitis Facts
Inflammation of lymphatic channels. Characterized by visible red streaking which stems from the inflammatory process in the walls of dilated lymphatic channels ("blood poisoning")
Lymphangitis Pathogen
Usually group A streptococci; rarely S. aureus or Pasturella multocida (bite infection)
Lymphangitis Treatment
Penicillin G IM
Ceftriaxone IM
Penicillin V PO
Amoxicillin PO
Dicloxacillin PO
Lymphadenitis Facts
Infection of a lymph node. Characterized by a tender, swollen node usually at least 3 cm in diameter. Fever is common and the overlying skin is red.
Lymphadenitis Pathogen
Group A streptococci or S aureus
Lymphadenitis Treatment
Penicillin G IM
Clindamycin (IV/PO)
Penicillin V PO
Amoxicillin PO
Erythromycin (IV/PO)
Cutaneous abscesses pathogens
Scalp, trunk and extremity: Staph aureus

Oral and nasal mucosa: Streptococci

Intertriginous/perineal: gram negative aerobes, S. aureus, anaerobes

Axila- P. mirabilis, Ps.aeruginosa, S. aureus

Perirectal/genital: anaerobic (bacteroides sp) and gram negative anaerboes
Cutaneous abscesses pathogens specifics
Foreign bodies- S. aureus

Cat/dog bites: Pasturella multicida, S. aureus, Viridans streptococci, oral anaerobes

Human bites- Eikenella corrodens, oral anaerobes, staph aureus, viridans streptococci

IV drugs- staph aureus, rare pseudomonas aeruginosa
Abx treatment of Cutaneous abscesses
Clindamycin IV/PO
Amoxicillin Clavulanate
Necrotizing soft tissue infx facts
Constant, severe pain
Bullae- big blisters
Skin necrosis or ecchymosis
Gas in the tissue (crepitus)
Necrotizing Fasciitis (NF)
Rapidly progressive soft tissue infection characterized by inflammation and necrosis confined to deep subQ fascial tissue. Superficial nerve and deep muscle usually spared.

Type 1- polymicrobial: S. aureus, Enterobacteriacea, Bacteroides sp, other anaerobes, non-group A strep

Type II- Group A strep

Type III- marine Vibrios- V. vulnificus
Risk factors for NF
Type 1 (Polymicrobial): DM, PVD
Type II (Group A strep): exposure to children w/ strep pharyngitis, HIV, IVDA, corticosteroid use, African American, antecedent VZV
Type III(vibrio): chronic liver disease, immunocompromise, iron storage disease
Treatment of NF
Prompt debridement of devitalized tissue

Type I NF (polymicrobial): Carbapenem or Piperacillin-tazobactam PLUS Vanco or Dapto OR
Aztreoname+Ciprofloxacin + (Clindamycin) or (Vancomycin in combination with metronidazole)

Type II NF (Group A strep): Pen G or Ceftriaxone + Clindamycin

Type III NF (Vibrio): Ceftazadime + Doxy OR Cefotaxime + Cipro
Necrotizing Cellulitis
Clostridial cellulitis- C. pefringes- Gas found within skin (crepitus); but fascia and muscle are spared

Non-clostridial: polymicrobial with anaerobics and gram+ves and gram-ves

Marine vibrios-wound infection or ingestion of raw seafood
Necrotizing Cellulitis Treatment
Clostridial- Pen G + Clindamycin or Ceftriaxone + Erythromycin

Polymicrobial- Carbapenem or Piperacillin-tazobactam PLUS Vanco or Dapto OR
Aztreoname+Ciprofloxacin + (Clindamycin) or (Vancomycin in combination with metronidazole)

Marine vibrios- Ceftazadime + Doxy OR Cefotaxime + Cipro
Fournier's Gangrene
Occurs primarily in male diabetics and usually effects the scrotum

Treatment: surgical debridement +
Carbapenem or Piperacillin-tazobactam PLUS Vanco or Dapto OR
Aztreoname+Ciprofloxacin + (Clindamycin) or (Vancomycin in combination with metronidazole)
Gas Gangrene (Clostridium myonecrosis)
Rapidly progressive and life threatening caused by gram+ve spore forming anaerobic bacilli

Pain out of proportion to clinical findings. Heaviness of affected part.

Clinical features: metabolic acidosis, leukocytosis, anemia, thrombocytopenia, coagulopathy
Gas Gangrene Treatment
Resuscitation: crystalloid, plasma, packed cells

Abx: Pen G plus clindamycin

Surgery: debridement or amputation is a mainstay

Hyperbaric oxygen after debridement
Gas Gangrene (nonclostridial)
Polymicrobial infection. Risk factors include DM and PVD. Pain not as pronounced.

Treatment: Early debridement and HBO &
Carbapenem or Piperacillin-tazobactam PLUS Vanco or Dapto OR
Aztreoname+Ciprofloxacin + (Clindamycin) or (Vancomycin in combination with metronidazole)
Streptococcal Myositis
Rare form of invasive group A strep, no gas production but very virulent. 80-100% mortality.

Treatment: debridement +
Pen G or Ceftriaxone + Clindamycin