Hand Infections
Paronychia

• Infection BENEATH EPONYCHIAL FOLD, begins dorsal to nail and may spread superficially around the nail 
• Most common pathogen – GPC, staph aureus
• Treatment
• Initially may involve just warm soaks, if abscess has developed will require drainage with the eponychial fold separated from nail, if abscess under nail must remove nail
• Acute (usually bacterial) –> augmentin etc
• Chronic (usually fungal) -> topical miconazole or terbinafin vs PO ketoconazole or fluconazole
• If treatment fails then tx with marsupialization 

Felon

• Presents with red, swollen, fluctuant fingertip 
• Most common pathogen – GPC, staph aureus
• tx: open longitudinally along point of maximum fluctuance, or use a lateral incision over mid axial line (ulnar for index, middle and ring, radial for small finger and thumb), debridement, soaks, antibiotics

Collar button abscess

• Infection of the interdigital web space 
• Presents with ABDUCTED digits and pain/swelling/erythema in web space
• Tx with incision and drainage using longitudinal volar and dorsal incisions, don’t incise all the way through web space, avoid motor branch of median nerve to thenar muscles 

Flexor Tenosynovitis 

• Kanavel’s signs: sausage swelling, tenderness along flexor sheath, flexed finger at rest, pain on passive extension
• Operative irrigation/drainage of flexor sheath
• Single incision
• Double incision with angiocath flow through
• May have to explore parona’s space (horseshoe shaped connection between the small finger and thumb sheaths)
• Most common bacteria is staph aureus but may have others (frequently tested)
• Marine exposure
• Flexor Teno with Minimal symptoms -> Mycobacterium marinum
• Tx with Clarithromycin
• Flexor tenor with severe systemic symptoms, severe swelling, hemorrhagic bullae -> vibrio vulnificus (gram negative bacillus)
• Tx with ceftriaxone, levofloxacin

Deep Space Infections:

• Thenar Space:
• Borders
• Dorsal border – fascia of Adductor pollicus
• Volar border – index flexor tendons
• Ulnar – midpalmar septum of third MC
• Radial – adductor pollicus insertion 
• Will see palmar ABduction of the thumb
• Pain exacerbated by passive adduction and opposition 
• Severe infections – extend to first webspace and dorsoradial hand, “Dumbbell or pantaloon infection”
• Midpalmar Space:
• Boundaries – deep to flexor tendons of long-small, superficial to metacarpals/IOs
• Radial border – septum of LF MC, Ulnar border – hypothenar muscles
• “Loss of palmar concavity”
• Typically spread from long/ring/or small finger flexor teno
• May be significant DORSAL hand swelling
• Hypothenar Space:
• Less common infection
• Radially hypothenar septum is border
• Incision over hypothenar muscles 
• Parona Space:
• Boundaries – PQ, digital flexors, FPL, vertical band of facia radial to FCU
• Contiguous with radial/ulnar bursa:
• Can develop “horseshoe abscess” with infection spread from either

Herpetic Whitlow

• HSV infection of the digits, may be seen in dentists or oral hygenists 
• Treatment – Observe, clean BID to avoid bacterial superinfection, DO NOT unroof
• Acyclovir vs valacyclovir if caught within the first 1-3 days

Septic arthritis & OM

• Infection of the joint space that can lead to permanent damage caused by bacterial toxin destruction of cartilage, increased pressure decreases perfusion to joint 
• Dx – PAIN AGGRAVATED BY JOINT MOTION, almost complete LOSS of motion 
• Must aspirate joint to confirm infection – WBC >50, Glucose 40mg less than fasting blood, bacteria on Gm stain
• Most common bacteria – S. Aureus, N. Gonorrhea, H. flu in kids 
• Tx – Surgically decompressed urgently + Abx
• Abx – First gen cephalosporin or clinda, N Gonnorrhea with IV Ceftriaxone

Bites:
Most common bacteria:

• Cat/dog = pasteurella
• Flavobacterium = freshwater fish
• Mycobacterium = bears and ferrets
• Vibrio = shark bites
• Humans = eikinella
• Cat bites more often become infected and cause abscesses since they have teeth that penetrate instead of open up the skin –> for that reason typically I&D almost all cat bites
• cat scratch fever (caused by bartonella)
• axillary node swelling, bump at site of bite/scratch
• —> NSAIDs, supportive treatment, time (up to 4 months)

Human bite (fight bite)

• Most common is strep viridians > staph > bacteroides > eikenella but eikenella is the one we are tested on most frequently
• Augmentin vs bactrim/clinda (if penicillin allergy)

Toxic shock syndrome

• May be seen in rhinoplasty patients with prolonged nasal packing (prior question)
• T>102, multisystem organ failure, rash, erythema extending away from surgical site
• Caused by toxins produced by staph (exotoxin1) or strep bacteria (enterotoxin a/b/c)
• Clindamycin inactivates the toxin + broad spectrum coverage for bacteria

SJS/TEN

• T cell mediated hypersensitivity to a DRUG (antibiotics, anticonvulsants, NSAIDs)
• Fever, painful vesiculobullous rash, mucosal involvement, full thickness necrosis, multi organ dysfunction
• Supportive treatment in burn center

Mucormycosis

• Nonpurulent necrotizing fungal infection, seen most commonly in diabetics
• On stain will show right angle nonseptate branching hyphae
• Aggressive debridement, strong antifungals

Necrotizing fascitis 

• Rapidly progressing soft tissue infection that does progressess along fascial planes 
• Polymycrobial (Strep pyogenes, ecoli, proteus, serratia, s aureus)
• Excessive toxin production of strep
• Erythema, bullae, sick as ****, clear grey dishwater fluid, crepitus
• Worst prognostic indicator is delay in surgical intervention

Other pathologies
Hidradenitis

• Originates from apocrine glands
• Hurley scale
• Stage I: separate abscesses which drain on their own
• Stage II: multiple abscesses which scar and require drainage
• Stage III: multiple scarring and tracking connected abscesses
• Early, solitary, uncomplicated – excision, steroid injections
• Widespread – antibiotics, hygeine, weight loss
• Recurrent, debilitating – excision and closure versus skin graft versus healing by secondary intent
• Commonly the answer on our inservice***

Pyoderma gangrenosum

• Skin ulceration and breakdown which looks infectious, keeps getting worse when you try to treat it
• Mediated by neutrophils, often seen with inflammatory bowel disease or inflammatory arthritis
• Diagnosis: biopsy
• Treatment: treat underlying disease, steroids

Follicular pyodermas

• Infection of hair follicles
• Includes: folliculitis, furuncles, carbuncles
• Treatment: local I&D vs antibiotics, hygeine

Misc:
Preoperative antibiotics indicated in…

• surgeries >2h
• any clean breast surgery
• contaminated surgery of hand or face 
• Gustillo III injuries (cephalosporin)
• Ancef – 1g <80kg, 2g >80kg 40 min prior to incision
• Vancomycin – 1-1.5g IV
• Clindamycin (for penicillin/cephalosporin allergies) – 600-900mg IV

So you drop something

• Bone – Decontaminate with betadine irrigation then saline rinse (triple antibiotic solution is off the market)
• “for a brief time it came into contact with a non-sterile surface but was treated appropriately”
• Anything other than bone – decontaminate thoroughly with chlorhexidine
• Wound is now considered class 3 (contaminated)
• Class 1 – clean – operative incision is made
• Class 2 – clean contaminated – operative incision made, also involves respiratory/GI/genitourinary tracts
• Class 3 – contaminated – operative incision with breach in sterile technique, or traumatic wound with outside contamination
• Class 4 – infected – old surgical wounds with evidence of existing infection or old traumatic wounds with existing infection

Buzzwords/miscellaneous

• Don’t forget a tetanus shot!
• Tetracyclines are not for kids <8; and quinolones are not for kids <18
• Clearly a skin infection from the water but no systemic illness = Mycobacterium
• Leeches –> aeromonas –> ciprofloxacin, tetracycline, bactrim, 3^rd gen cephalosporins
• Cdiff –> flagyl for mild/moderate, PO vanc or fidaxomicin for severe
• Cervical necrotizing fasciitis = Comes from pharyngitis
• Diabetes + nasty necrotizing nonpurulent infection = Mucormycosis
• If it sounds like nec fasc it probably is nec fasc
• Immunosuppressed = Suspect TB (rice bodies, ziehl-neelsen stain, lowenstein jensen medium)
• dental hygienist: herpetic whitlow
• Nail biting/dishwashing: paronychia
• XR, MRI is most sensitive for fluid collection
• gas: gas gangrene/nec fasciae
• periosteal reaction: osteomyelitis
• MRSA De-Colonization
• Only thing proven to decolonize is mupirocin ointment and chlorhexidine body wash x5 days

Sources:
ACAPS Inservice 2013-2020
Plastic Surgery Emergencies