44. A 23 year old man presents with acute
cellulitis around
the right knee with lymphangitis along the medial thigh and tender
right
inguinal lymphadenopathy. His temperature is 38.3°. He sustained a
wound over
the right knee 10 days ago. The wound appeared to heal fairly well
initially
but redness and tenderness commenced two days ago. How will you
manage him?
This
young man
presents with features of wound infection complicated by acute
cellulitis,
lymphangitis & lymphadenitis
Given
the location
over an underlying joint, this is a high-risk infection
I
would manage this
problem by performing a thorough clinical assessment & some
investigations
with a view to:
Followed
by the
appropriate treatment & arrangement of F/U
In
further detail,
I would
1)
Further
focused history- to confirm dx & exclude complications
a.
Cause
of wound- guide to likely organism & Rx
i.
Laceration/ cut/ penetrating
injury
ii.
Dirty/ soiled wound
iii. Animal or human bite
iv.
Water-related injury
1.
Fisherman
2.
Swimmers
3.
Aquarium owners
b.
Consequences
i.
Cellulitis
1.
Spreading, tender erythema
2.
+ Fever & systemic
toxicity
3.
+/- Lymphangitis/
lymphadenitis
4.
+/- Blistering
ii.
Lymphangitis
iii. Lymphadenitis
iv.
Septic arthritis
v.
Osteomyelitis
vi.
Necrotising fasciitis
1.
Severe systemic toxicity
vii. Septicaemia
c.
Past Hx
i.
Immunosuppression
1.
Atypical organisms
2.
Lower threshold for IV
treatment
ii.
Prostheses
1.
Joint
2.
Vascular
d.
Medications
i.
Previous antibiotic
treatment- resistance
ii.
Interactions
iii. Tetanus vaccination status
e.
Allergies
i.
Penicillin
f.
Social
history
i.
Ensure compliance with Ax
treatment &
F/U
2)
Examination
a.
General
i.
Vital signs
ii.
Hydration status
b.
Wound
(portal of entry)
i.
Open or closed
ii.
Inflammation
iii. Abscess formation- fluctuance
c.
Complications
i.
Surrounding tissue-
cellulitis
ii.
Inguinal LNs- tender
lymphadenopathy
iii. Knee Jt
1.
Red flags for septic
arthritis
a.
Swelling
b.
Erythema
c.
Marked reduction in ROM
d.
Systemic features of
inflammation
3)
Investigations
a.
Bloods
i.
FBC/ ESR/ CRP
ii.
Blood cultures?
1.
Low diagnostic yield < 5%
b.
Imaging
i.
Knee X-ray- AP/ Lat/ oblique
c.
Microbiology
i.
Wound swab
ii.
Joint aspirate +/- knee US
4)
Admit
to hospital for IV Axs (or HITH program)
a.
Complicated
cellulitis over large joint
b.
Significant
systemic features
5)
Treatment
a.
Non-pharmacological
i.
Rest
ii.
Elevation of limb
iii. Delineate margins with a
textor
iv.
Non-adhesive dressings
b.
Pharmacological
i.
Analgesia
ii.
IV Antibiotics
1.
Flu/dicloxacillin 2g IV qid
OR if penicillin hypersensitivity
2.
Cephazolin or Cephalothin IV
OR if immed pen hypersensitivity
3.
Clindamycin IV or Lincomycin
IV
OR
4.
HITH IV therapy
a.
Cephazolin 2g IV daily
+ probenacid
PO 1g daily
b.
Cephazolin 2g IV bd
iii. Treatment of underlying cause
1.
Tinea pedis
2.
Dermatitis
iv.
DVT prophylaxis- if
immobilised for a while
1.
Compression stockings
2.
+/- UF heparin SC 5000 u bd
c.
Surgical
i.
Joint lavage/ wash-out
6)
Ongoing
management
a.
Supportive
therapy
b.
Change
to oral Axs
i.
Afebrile
ii.
+ Substantial improvement in
erythematous
rash
1.
From 3 days- 2 wks!
iii. Continue oral Axs for further
10 days
7)
Follow-up
Cellulitis
Mild early cellulitis or erysipelas
Severe cellulitis
Severe systemic symptoms
Unresponsive to PO Rx after 48 hrs
OR
Erysipelas
Necrotising
fasciitis
PLUS
PLUS
+/-
DD –
gout, septic
arthritis, osteomyelitis
NB –
the
lymphangitis, acute onset, tender lymphadenopathy all indicate
Strep pyogenes
as the cause. Spreads by hyaluronidase + streptokinase enzymes
Other
micro – S
Aureus (remember MRSA if he has been hospitalised) – high risk
as post injury
History
Examination
Investigations
Management