84th Annual Meeting of Fumaric Acid Esters for Severe

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Transcript 84th Annual Meeting of Fumaric Acid Esters for Severe

M62 Course – Cedar Court Hotel, Huddersfield
7th April 2005
The Dermatologist and
Pruritus Ani
MJ Harries and CEM Griffiths
Dermatology Centre, Hope Hospital,
Manchester, UK
“An unpleasant cutaneous
sensation that induces the desire
to scratch the skin”
Itch-Scratch Cycle
DAMAGED
PERIANAL SKIN
PRURITUS
SCRATCHING
Classification of Itch
 Pruritoceptive itch
 Originates in the skin
 Neurogenic itch
 Originates in the
nervous system
 Itch specific neuronal
pathway (C-fibres and
spinothalamic tracts)
Yosipovitch et al. Lancet 2003; 361:690-694
Causes of Pruritus Ani
 Anal pathology
 Infections
 Skin disease
 Contact allergy
 Underlying medical conditions
 Idiopathic
Causes of Pruritus Ani
 Anal pathology
 Infections
 Skin disease
 Contact allergy
 Underlying medical conditions
 Idiopathic
Skin Disease
 85% consecutive patients referred to a
combined colorectal and dermatological clinic
had an underlying dermatosis
 Over half had a positive patch test
“Patients with long-standing pruritus ani with no
other symptoms to suggest colorectal pathology
should be referred to a dermatologist for
assessment and patch testing.”
Dasan et al. Br J Surg 1999; 86: 1337-40
Psoriasis
 2% population
 Approx. 1.2 million
sufferers in the UK
 Immune-mediated
disease
 Positive family history
common
Psoriasis
 Symmetrical
 Extensor aspects
 Elbows / knees
 Scalp
 Umbilicus
 Natal cleft
 44% perianal
involvement
Farber et al. Dermatologica 1974;148:1-18
Psoriasis - Perianal
Psoriasis - Perianal
Where else to look?
Where else to look?
Lichen Planus
 Idiopathic
inflammatory disease
of the skin and
mucous membranes
 Common sites
 Flexor wrist
 Anterior lower leg
 Neck
 Presacral area
 75% oral involvement
Lichen Planus
 Polygonal,
violaceous, flattopped papules
 Wickham’s striae
 Pruritus +++
Lichen Planus - Perianal
Lichen Planus - Perianal
Where else to look?
Where else to look?
Lichen Sclerosis
 Idiopathic
inflammatory disease
that preferentially
affects the anogenital
region
 Hypopigmented and
atrophic skin
 Figure-of-eight
distribution (women)
 5% risk of SCC
Lichen Sclerosis - Perianal
Seborrheic Eczema
 Link with sebum
overproduction and
the commensal yeast
Malassezia furfur
 Red-brown patches
with “greasy” scale
 Common sites
 Scalp
 Nasolabial folds
 Central chest / back
 Flexures
Where else to look?
Lichen Simplex – The Itch that
rashes
 Itching often localised
to one site resulting in
lichenification
 Itch / scratch cycle
develops
 Common sites
 Perineum
 Scrotum / vulva
 Posterior neck
 Lateral lower legs
Lichen Simplex - Perianal
Allergic Contact Dermatitis
 55 / 80 (69%) clinically relevant allergic
reactions
 38 of these reactions to medicaments or
their constituents
 Improvement or resolution of symptoms in
¾ patients with avoidance advice
 Advise patch testing at an early stage
Harrington et al. BMJ 1992; 305: 955
Eczema - Perianal
Patch Test
 Common allergens
placed into Finn
chambers
 35 common allergens
tested in the BCDS
standard series
 Extra allergens tested in
the perineal series
 Type IV delayed
hypersensitivity response
Patch Test – 0h
Patch Test – 48h
Patch Test – 96h
 Grading system for
reactions
Negative
+/- Doubtful
+ Weak
++ Strong
+++ Very strong
Common Perianal Allergens






Local anaesthetics
Corticosteroids
Neomycin
Perfume
Preservatives
Antiseptics
Goldsmith et al. Contact Dermatitis 1997;
36: 174-5
Pruritus Ani and Underlying
Medical Conditions
 Consider a “pruritus
screen” if generalised itch
is also present
 Common causes include




Iron deficiency
Renal failure
Hepatic/ biliary disease
Malignancy
 FBC
 Ferritin / serum Fe / % sat /
TIBC
 ESR
 U&E
 LFT
 TFT
 Glucose
 Calcium
 Serum electrophoresis
 CXR
Idiopathic Pruritus Ani
 Faecal contamination
 Difficulty in cleaning the area
 Anal sphincter dysfunction
Farouk et al. Br J Surg 1994; 81: 603-606
 Dietary causes
 Lumbosacral radiculopathy
 16 / 18 (80%) lubosacral radiculopathy confirmed by N.C.S
 Paravertebral injections of steroid / lignocaine resulted in
reduced pruritus
Cohen et al. J Am Acad Dermatol 2005; 52 :61-6
Treatment - General Advice
 Wash after every B.O
and twice a day
 Avoid irritants
 Keep the area dry
 Wear cotton
underwear
 Keep bowels regular
Alexander-Williams J. BMJ 1983;287:1528
Topical Steroids
 Mild, moderate, potent and very potent
 Treats inflammation
 Break the itch-scratch cycle
 As control is achieved the potency should be
reduced
 If not improving consider
 ?Appropriate potency for condition
 ?steroid allergy – Patch test
 ?correct diagnosis - Biopsy
Other Treatments
 Topical Capsaicin
 Placebo controlled trial
 0.006% capsaicin cream t.d.s for 4 weeks
 31 / 44 (70%) responded
Lysy et al. Gut 2003; 52: 1323 – 1326
 Intradermal methylene blue injections
 1% methylene blue / hydrocortisone / lignocaine
 88% patients responded
Botterill et al. Colorectal Dis 2002;4:144-6
Summary
 Examine the entire skin surface including
nails and mucous membranes
 Consider patch testing early in
management
 Consider skin biopsy if any diagnostic
doubt or if the condition is not responding
to appropriate treatment