Makindo Medical Notes

Related Subjects: |Nikolsky's sign |Koebner phenomenon |Erythema Multiforme |Pyoderma gangrenosum |Erythema Nodosum |Dermatitis Herpetiformis |Lichen Planus |Acanthosis Nigricans |Acne Rosacea |Acne Vulgaris |Alopecia |Vitiligo |Urticaria |Basal Cell Carcinoma |Malignant Melanoma |Squamous Cell Carcinoma |Mycosis Fungoides (Sezary Syndrome) |Xeroderma pigmentosum |Bullous Pemphigoid |Pemphigus Vulgaris |Seborrheic Dermatitis |Pityriasis/Tinea versicolor infections |Pityriasis rosea |Scabies |Dermatomyositis |Toxic Epidermal Necrolysis |Stevens-Johnson Syndrome |Atopic Eczema/Atopic Dermatitis |Psoriasis

About

• Common skin infection affecting the subcutaneous tissues with overlying inflammation
• Caused by Streptococcus pyogenes or Staphylococcal aureus

Risks

• Lymphoedema, Skin trauma, tinea pedis
• Venous insufficiency, Leg oedema, Obesity

Clinical

• Bilateral leg cellulitis is rare - question diagnosis
• Red erythematous swollen and tender skin but not usually pus formation
• Warmth, Swelling may be fluctuant, Tender/painful
• Demarcated, Crepitus, Pyrexia
• Look for an entry point - between toes and always lift up and inspect back of legs and examine local lymph nodes. In other sites e.g. perineum etc always look for skin breaks.
• Useful to mark margins with a marker pen to see that treatment is working

Differential

• DVT if entire leg swollen or previous DVT or active cancer or palliative or paralysis, paresis or recent immobilisation
• Lymphangitis, Abscess, Venous eczema/ulcers
• Necrotising fasciitis, Gas gangrene, Osteomyelitis
• DVT is a common differential

Severe If any of following present:

• Lesion spreading rapidly
• Temperature >38 C
• Hypotension, tachycardia
• Cellulitis involving face or hand
• Progression despite adequate doses of appropriate oral antibiotics
• Asplenia, neutropenia, cirrhosis, immunocompromised
• Cardiac or renal failure, or pre-existing oedema

Gradings of Cellulitis

Likely organisms

• Staphylococcus aureus
• ß haemolytic streptococci
• Anaerobes, particularly in patients with diabetes and/or ischaemic limbs

Those at risk

• Diabetic, IV drug user
• Immunocompromised
• Peripheral vascular disease

Investigations

• FBC - elevated WCC, ESR CRP - elevated
• U&E, Glucose - always consider and test for diabetes with at least a random glucose
• Blood culture

Management

• If systemically unwell or pyrexial send blood culture specimen. Swab from any pus or portals of entry. If osteomyelitis suspected plain X-ray. If gas gangrene is suspected, seek urgent surgical advice. Outline periphery of erythema with pen (indelible ink if possible)
• Cellulitis - likely causes are Staph aureus and Group A streptococci: Benzyl Penicillin 1.2g qds IV plus Flucloxacillin 1g qds IV until patient shows clinical improvement when oral antibiotics can be used e.g. use Amoxicillin 500mg tds and Flucloxacillin 500mg qds treat for a minimum of 7 days (CREST guidelines 2005)
• For Penicillin allergy use Teicoplanin 400mg IV once daily (after 3 loading doses of 400mg 12 hrly)
• For early discharge where IV may still be indicated use Teicoplanin 400mg IV once daily
• Patient with diabetes (Diabetic foot) likely causes usually polymicrobial: Staph aureus, streptococci and gut flora a) Mild infections: Co-Amoxiclav 625mg tds PO or clindamycin 300mg qds PO if Penicillin allergic. Prolonged diabetes/podiatry follow-up will be needed. Cellulitis: As cellulitis management above.
• Severe infections: Severe/limb threatening diabetic/Hot Foot is a medical emergency that requires coordinated input from the Diabetes Podiatrist, Consultant Diabetologist and Consultant Microbiologist in addition to surgical input. Co-Amoxiclav 1.2g tds IV For Penicillin allergy contact Consultant Microbiologist. Clindamycin may be added if there is bone involvement, on the advice of a Consultant Diabetologist or Microbiologist
• Treat tinea pedis, E45 and emollients to improve skin condition