Infections Flashcards
What is this?
What is its pathology?
Herpetic Whitlow
Viral infection of the finger by Herpes Simplex 1- HSV1
Who is hepetic whitlow common in?
What is its pathphysiology?
Dental / medical personnel
Commonly effects toddlers and preschool children
viral shedding occurs with vesicles forming bullae
What are the symptoms and signs of someone with herpetic whitlow?
Intense burning then erytherma, malaise
O/e= erytherma then small vesicular rash
over 2 weeks vesicles may merge to -> bullae
Fever and lymphadenitis
How is hepetic whitlow confirmed?
TZANK smear
Diagnosis confirmed by culture, antibody titers or Tzank smear
How is this treated?
What are the complictions?
1) Non operative and Acyclovir
standard tx- resolution 7-10 days
acyclovir may reduce time of symptoms
2) Operative = AVOID as- associated with superinfections, encephalitis and death!!
Complications include SUPERINFECTIONS- may require further antibiotics oral- pencillinase resistance for 7-10 days
What is this?
What is its incidence?
What is it’s pathology?
Paronychia
Most common hand infection- children and women (3:1 cf males)
Most commonly affects the thumb
Break in seal between nail fold and plate allows bacteria to gain entry- result of nail biting or manicures
What is the common organism in acute and chromic paronychia?
ACUTE
Adults- Staphyloccus aureus
Children/ Diabetics**-mixed oropharyneal **
CHRONIC
Candida albicans- common diabetics, often unresponsive to antibiotics
What are the causes of acute paronychia?
Nail biting
Manicures
Thumb sucking
What are the causes of Chronic paronychia?
What are the risk factors for developing chronic paronychia?
Occupational exposure to water and irrants acid/alkali
RF= Diabetes
Psorasis
Steroids
Retroviral drugs- Indinavir= HIV +ve pts.*
*Resolves on withdraw of medication
What is the role of the nail organ?
Adds Stability to finger tip as counterforce to finger pulp
Thermoregulation- glomus bodies of nail/ nail bed
Extended Percision Grip- opposing thumb/index nails to remove a splinter
What is the nail plate made of and how much does it grow?
Where does it grow from
Made of keratin
Grows 3mm/ month, faster in summer
fingernails row faster than toes ( finger nails 3-6 months to regrow, toes 12-18 months)
Growth part is under eponychium
What are the symptoms of acute paronychia?
Pain
Nail fold tenderness
Erytherma
Swelling
What are the symptoms of chronic paronychia?
RECURRENT Boats of low grade inflammation
What do you find on examination of
1) acute paronychia and 2) chronic paronychia?
1) acute= Fluctuant
Nail plate discolouration- green= pseudomonas
2) Chronic ( see pic)- Nail plate hypertrophy- fungal infection
Nail fold blunting and retraction after rpt boats of inflammation
Prominent transverse ridges on nail plate
What are your differential diagnosis of a person with acute paronychia?
Herpetic whitlow
Felon
Onychomycosis
Psorasis
Glomus tumour
Mucous cyst
How do you tx acute paronychia?
Non operative- > Swelling but no fluctation= Warm soaks, oral antibiotics ( augmentin/clindamycin) and avoid nail biting
_Operative= fluctuation= _ Incision and drainage with partial or total nail bed removal
How do you tx chronic paronychia?
Non operative- warm soaks, avoid finger sucking, topical antifungals ( miconazole)- rarely antibiotics effective
Operative = Marsupialization ( See pic)= Excision of 3mm dorsal eponychrium crescent shape down to level of Germinal matrix ) combine with nail plate removal =Heal by secondary intention
Decribe your operative teachnique for incision and drainage of an acte paronychia with partial nail removal?
Approach
Incision into sulcus between lateral nail plate and lateral nail fold
Technique
preserve Eponychial fold by placing materials (removed nail) between skin and nail bed
If abscess extends proximally over eponychium (eponychia), a separate counterincision is needed over the eponychium
Obtain gram stain and culture
What are the complications of paronychia?
Eponychia- spreads to eponychium
Run around infection- both lateral folds involved
Felon- spreads to volar pulp- I& D required
Flexor tenosynovitis- volar spreads to felxor sheath
Subungual abscess- floating nail
What is this?
How does it occur?
A Felon
Infection of the volar pulp of the fingertip
Local spread from paronychia
Penetrating injury/ needle stick
Describe the anatomy of the pulp?
multiple small compartments of subcutaneous fat separated by fibrous septae between the distal phalanx and dermis
What is the pathology of a felon?
Swelling and pressure within micro-compartments, leading to “compartment syndromes” of the pulp
What are the causative organisms?
Staphylococcus aureus- most common
Gram negative organism- immunosupressed
Eikenella corrodens- in diabetics
What are the symptoms of a felon?
What are the signs ?
Pain and swelling of the finger pulp
Tenderness on palpation of the pulp
How do you tx a Felon?
Operative- incision and drainage
Due to risk of finger tip compartment syndrome
Can you describe the technique of incision and drainage of a Felon?
Approach:
Keep incision distal to DIP crease -T
o prevent DIP flexion crease contracture and prevent extension into flexor sheath.
Mid lateral approach - see picture below- Indicated for deep felons with no foreign body and not discharging.
Incision on ulnar side for digits 2,3 and 4 and radial side for thumb and digit 5 (non-pressure bearing side of digit)
Longitudinal approach ( see pic) most direct)
Indicated for superficial felons, foreign body penetration or visible drainage .
AVOID FISH MOUTH INCISIONS-> unstable fonger pulp
DOUBLE LONGITUDINAL or transverse incision - injury to digital nerve and artery