Download Pruritus and logical management

Dr Neda Adibi
Dermatologist and researcher of Isfahan university of
medical sciences
Pruritus
 The most common (10-50%) complaint in
dermatology
 With or without skin lesion
 With or without systemic problems
 Elicit desire to scratch
 Primary or secondary
What is pruritus
 a sensation that causes the desire or reflex to scratch.
• has many similarities to pain, and while both are
unpleasant sensory experiences, their behavioral
response patterns are different.
• Pain creates a withdrawal reflex, while itch leads to a
scratch reflex
Epidemiology
 Pruritus occurs in approximately 20% of adults. It is
present in approximately 25% of patients with jaundice
and in 50% of patients receiving renal dialysis.
 An underlying systemic disease is reported in 10-50%
of patients who seek medical attention for pruritus.
 Pruritus is more common in elderly people
Pathophysiology
• The sensation of pruritus is transmitted through slow-
conducting unmyelinated C-polymodal
and possibly type A delta nociceptive neurons with
free nerve endings located near the dermoepidermal
junction or in the epidermis.
• These neurons appear to be located more
superficially and are more sensitive to pruritogenic
substances than pain receptors. Activators of these
nerves include histamine, neuropeptide substance P,[1]
serotonin, bradykinin, opioid peptides .[2]
Complication
• Debilitating sleep deprivation and suicidal
ideation
• Women with untreated intrahepatic cholestasis
of pregnancy that begins before 33 weeks of
gestation have increased rates of preterm
deliveries and stillbirths.
• lichen simplex chronicus, prurigo nodules, and
excoriations
complication
 Renal pruritus is an independent marker for mortality
at 3 years for patients on HD.
 Patients with severe generalized pruritus and Hodgkin
disease have a poor prognosis.
 Pruritus that recurs after treatment is useful in
detecting recurrence of the cancer.
 Many of the therapeutic modalities listed in the
Treatment and Medication sections offer only
symptomatic control. Only cure of the underlying
condition results in complete resolution of pruritus.
During treatment to relieve symptoms, every effort
should be made to treat the underlying systemic
disease.
management
• The management of pruritus is challenging especially
when an underlying etiology cannot be identified. Due
to the poorly understood pathophysiology, the
development of effective treatment modalities for
pruritus has proven to be particularly difficult.
. General Principles in the
Treatment of Pruritus
• There are a number of possible underlying etiologies
for pruritus .
• Detailed Hx and physical exam
• If an underlying cause is discovered it should be
treated
• . Topical
therapies are the mainstay of
therapy for mild and localized itch while
systemic therapies should be considered for severe
and generalized itch.
Topical emolient
and moisturizer
Improving the
barrier function
Corticosteroid
Not having the direct anti
pruritus effect but can
decrease the inflamation
Topical calcineurin
inhibitors
Tacrolimus 0.03 -0.1 %
specially effective in atopic
dermatitis pruritus and
anogenital pruritus
Doxepin 5%
Not should be used in
children because of risk
of sedation
Capsaicin
0.025%–0.1% cream
Lidocaine patch 5%
Useful in neuropathic
pruritus
Particularly useful in
neuropathic itch, may
experience initial
transient burning
• . The possible causes for itchiness range from internal
illnesses,
such as kidney or liver disease,
to skin rashes, allergies, and
dermatitis.
• categories on the basis of the underlying causative disease:
renal pruritus, cholestatic pruritus,
hematologic pruritus, endocrine
pruritus, pruritus related to
malignancy, and idiopathic generalized
pruritus
What is dermatitis
 symptoms of dermatitis may include a red rash,
blisters, and dry, cracked skin. Itchy skin is also
common and can become severe. The skin may
become painful, with stinging or burning.
What Are the Risk Factors For
Dermatitis
 a family history of dermatitis .
 a family history of asthma or hay fever increases the
risk of atopic dermatitis.
 People who work with or near strong chemical
substances
How Is Dermatitis Prevented
• Dermatitis often runs in families, so it is not always
preventable. But it is possible to prevent symptom
flare-ups.
• People with allergies should avoid skin contact with
allergens. Frequently moisturizing the skin can also
help.
• Avoid excess drying of the skin by reducing bath time
to 15 minutes or less, and use warm water instead of
hot water. Use mild soaps and detergents, which are
less likely to irritate the skin.
• Home care for dermatitis may include applying cool, wet
cloths to the skin. Covering the skin with a dressing or
bandage prevents scratching or infection if the skin is
broken.
• Dermatitis is sometimes associated with an increase in
stress. Alternative therapies may help reduce stress. These
include acupuncture, massage, and medications.
• Other alternative therapies, such as herbs and dietary
supplements, may be used to treat dermatitis. Some studies
indicate that children under the age of 13 may reduce
eczema by taking probiotics
Types of Dermatitis
• , the two most common types are contact
dermatitis and atopic dermatitis.
• Contact dermatitis skin comes in direct contact with
an allergen. This causes an allergic reaction.like
poison oak, poison ivy, detergent, perfume, cosmetics,
and nickel.
• Atopic dermatitis is also called eczema. It can be
chronic and may first start in infancy. It tends to run in
families with a history of allergies
• Treatments for dermatitis depend on the severity of
symptoms and the cause. Medication is often the main
treatment.
• Topical creams containing hydrocortisone can
reduce inflammation, redness, and
itching.
• Antihistamines are sometimes recommended in order to
reduce allergic reactions, which can cause dermatitis.
• Antibiotics are usually given only if an infection has
developed. Infections can occur when the skin is broken
due to intense scratching.
Other causes of dermatitis
 1)thromboflebitis
 2)dermatomyosistis
 3)cellulitis
 4)graft versus host
 5)candida skin infection
 kwashiocor
. How Is Contact Dermatitis
Treated?
• Avoid scratching
• clean skin with soap and lukewarm water to remove
any irritants. Soak a washcloth in the cool water, wring
it out, and apply it to the skin.
• calamine lotion or hydrocortisone cream.
• Taking an antihistamine drug such as
diphenhydramine
• Most cases of contact dermatitis will go away on their
own and aren’t cause for concern.
Moisturizers, Emollients and
Barrier Creams
• improved barrier function
• Transepidermal water loss (TEWL) is associated with
itch intensity in patients with atopic dermatitis. This
observation may be explained by the suboptimal
epidermal barrier function facilitating the entry of
irritants and itch-causing agents.
Topical Corticosteroids
• Topical corticosteroids should only be used to provide
relief of itching associated with inflammatory skin
diseases such as atopic dermatitis or psoriasis.
• should not be used to treat generalized chronic itch or
for prolonged periods. Corticosteroids are not directly
antipruritic and it is believed they exert a beneficial
effect on pruritus through their reduction in skin
inflammation.
Topical Immunomodulators
• The topical calcineurin inhibitors (TCI), tacrolimus
and pimecrolimus, have been shown to be effective
in reducing pruritus in atopic dermatitis ,
chronic irritative hand dermatitis,
graft-versus host disease, lichen
sclerosis, anogenital pruritus and
prurigo nodularis.
• Common side effects of these agents are transient
burning and stinging sensations
 Pimecrolimus is indicated only after other treatment
options have failed. Use short-term and for
intermittent use only.
Topical Antihistamines
• Doxepin, a tricyclic antidepressant, is a potent H1 and
H2 antagonist.
• Doxepin 5% cream has been shown to significantly
reduce pruritus in patients with atopic dermatitis,
lichen simplex chronicus, contact dermatitis and
nummular dermatitis.
• drowsiness, through systemic absorption of doxepin,
occurs in approximately 20 -25% of patients, limiting
its use especially in children. Other common side
effects of this treatment include localized cutaneous
burning and allergic contact dermatitis.
Menthol
• Menthol has been used alone or in combination as a
topical antipruritic for centuries.
• Menthol at concentrations of 1 – 3 % being commonly
used to relieve pruritus while higher doses can induce
irritation.
• Of note, patients who report a reduction in pruritus
with cold sensation may especially benefit from topical
therapies containing menthol.
Capsaicin
• Beneficial effects in chronic, localized pruritic disorders,
particularly those of neuropathic origin, such as notalgia
paresthetica and brachioradial pruritus as well as other
pruritic conditions (e.g. prurigo nodularis, aquagenic
pruritus and pruritus associated with chronic kidney
disease).
• Initial application causes an intense transient burning
sensation at the application site which may lead to poor
compliance or premature cessation of treatment; however,
this side effect usually resolves after using the medication
for a few days or with application of a topical anesthetic.
Local anesthetics
• Topical local anesthetics such as pramoxine 1 percent,
lidocaine 5 percent and the eutectic mixture of
lidocaine 2.5 percent and prilocaine 2.5 percent, have
all been shown to have antipruritic properties.
Antihistamin
 Oral antihistamines have traditionally been the
cornerstone of pruritus treatment. With the exception
of urticaria, antihistamines have little effect on
conditions associated pruritus.
 sedating (first-generation) antihistamines may have a
role in patients where pruritus is exacerbated at night
probably via their soporific
 effects.In cases of urticaria, sedative antihistamines,
such as hydroxyzine, may be particularly valuable
with pruritus during the night while non-sedating
(second-generation) antihistamines such as
loratadine, desloratadine, cetirizine and
levocetirizine may be suitable in the daytime for relief
of pruritus.
Antidepressants
Mirtazapine, has been reported to relieve itch in
patients with advanced cancer, leukemia, lymphoma
(including cutaneous lymphoma), chronic kidney
disease, cholestasis and atopic dermatitis.
• Mirtazapine is a relatively safe for the treatment of
nocturnal pruritus.
• venlafaxine and duloxetine do not seem to have
significant antipruritic effects in our experience.
 paroxetine and fluvoxamine, were shown to reduce
chronic pruritus, with the most favourable responses
being seen in patients with pruritus due to atopic
dermatitis, systemic lymphoma and solid carcinoma.
 Sertraline, another SSRI, has also been shown to an
effective, well-tolerated treatment for pruritus due to
chronic liver disease.
• Several studies have shown the antipuritic effects of μ-
opioid receptor antagonists such as naltrexone and
nalmefene. Natrexone has been reported to reduce
pruritus in patients with cholestasis, end-stage renal
disease, burns and atopic dermatitis.
• butorphanol and nalfurafine appear to be beneficial in
pruritic conditions.
. Gabapentin may be particularly useful in forms of
neuropathic pruritus related to nerve entrapment
disorders such as brachioradial pruritus and notalgia
paresthetica
100-300 mg / day specially after hemodyalysis and
cutaneus T cell lymphoma
, cyclosporine and azothioprine, have demonstrated
antipruritic effects in patients with atopic dermatitis
most likely through their anti-inflammatory effects. It
is recommended that oral cyclosporine and
azathioprine, only be used in the short-term for
patients with atopic dermatitis who have failed
conventional therapy and with appropriate
monitoring.
Renal pruritus
 In CRF specially in those with HD
 Not related to uremia
 elevated levels of circulating histamine in patients
receiving HD.
 increased numbers of mast cells in various organ
systems. antihistamines are, at best, marginal in the
treatment of renal pruritus
• Elevated levels of divalent ions, such as calcium,
magnesium, and phosphate, are thought to play a role.
• Marked improvement of pruritus resulting from low
dialysate calcium and magnesium concentrations has
been reported
• Decreased transepidermal elimination of pruritogenic
substances, xerosis, elevated levels of serum bile acids,
and increased epidermal vitamin A levels all may
contribute to the condition. Elevated
 . In patients with CRF, a systemic inflammatory
response involving overexpression of activated type 1
helper T lymphocytes (which secrete interleukin 2)
may induce pruritus. UV-B, thalidomide, and
tacrolimus all target mediators of this inflammation.
Elevated ferritin and low transferrin and albumin
levels have been correlated with the severity of
pruritus.
Cholestatic pruritus
 some combination of the pruritogenic substances
mentioned above (ie, bile salts, histamine, opioids)
induces cholestatic pruritus.
Hematologic pruritus
 Patients with pruritus and iron deficiency may not be
anemic; this observation suggests that pruritus may be
related to iron and not hemoglobin.
 Polycytemia Vera
 Hodgkin lymphoma
Endocrine pruritus
 Hyper and hypotyroidism
 Diabetes mellitus
• Therefore, a thorough history, including the onset, duration,
severity, location, provoking factors, time relation, and
relationship to activities such as bathing should be discussed
with the patient who presents with pruritus.
• A review of systems is needed to uncover signs and symptoms
associated with systemic disease and to direct the physical
examination and laboratory evaluation. A detailed drug history
is required to exclude medications that can cause itching. A
history of alcohol abuse may indicate chronic liver disease. A
review of potential emotional stresses and mental health history
may reveal a psychiatric cause.
• Clues supporting a systemic cause include the insidious onset of
generalized pruritus rather than an acute presentation.
Physical examination
• assists in differentiating between systemic causes of pruritus and
primary dermatologic conditions. When systemic disease
underlies pruritus, patients may have normal-appearing skin or
secondary lesions, such as excoriations, prurigo nodules, lichen
simplex chronicus, or signs of a secondary bacterial infection.
Patients may have the butterfly sign, which is an area of relative
hypopigmentation or normal skin on the middle of the back in
combination with areas of postinflammatory hyperpigmentation
in locations accessible to the patient's hands. Other signs of
systemic disease are as follows:
• Renal pruritus: Diffuse xerosis and half-and-half nails may be
seen. The patient may have signs of peripheral neuropathy and
uremia.
• Cholestatic pruritus: Signs of liver disease include jaundice, spider
angiomata, Dupuytren contractures, white nails, gynecomastia in men,
xanthelasma, splenomegaly, and ascites.
• Endocrine pruritus: Patients with hypothyroidism have brittle nails
and dry, course skin and hair. Patients with hyperthyroidism may have
warm, smooth, and fine skin. They may also have chronic urticaria and
angioedema. Other signs are fever, tachycardia, exophthalmos
(associated with Grave disease), and atrial fibrillation.
• Hematologic pruritus: Patients with iron deficiency may have pallor if
they have anemia; they might also have glossitis and angular cheilitis.
Polycythemia vera may result in a ruddy complexion around the lips,
cheeks, nose, and ears, along with hypertension and splenomegaly.
• Pruritus and malignancy: Patients with Hodgkin disease may have illdefined hyperpigmentation of the skin, ichthyosis, nontender
lymphadenopathy, and splenomegaly.
Laboratory Studies
• When a primary dermatologic condition is excluded and a systemic cause is
suspected, certain laboratory tests may aid diagnosis. If suspicion is low
concerning a systemic disease, a 2-week trial of therapy with
oilated soap for bathing, emollients for after the
bath, and oral antihistamines may be
attempted. If this fails, a laboratory evaluation
is indicated.
• The following screening laboratory tests are recommended:
• CBC count with differential: This test assists in uncovering polycythemia vera,
in which the hemoglobin level, hematocrit value, WBC count (including
absolute neutrophil count; see the Absolute Neutrophil Count calculator), and
platelet count are elevated. Abnormalities are also seen in persons with
hematologic malignancies. Patients with iron deficiency may have microcytosis
and low hemoglobin levels. However, those with pruritus and iron deficiency
may not be anemic; tests of and serum iron, ferritin, and total iron-binding
capacity may be ordered to confirm or exclude the diagnosis.
• Serum creatinine and blood urea nitrogen values: Persons with CRF have
elevated levels.
• Serum alkaline phosphatase and bilirubin, direct and indirect: Elevated levels
may suggest cholestasis. If elevated, antimitochondrial antibody and serum
anti–hepatitis C tests may be ordered to confirm primary biliary cirrhosis and
hepatitis C, respectively, if these are suspected. Other tests may be needed to
confirm other causes of cholestasis. A positive antimitochondrial antibody
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finding has 98% specificity for primary biliary cirrhosis.
Thyrotropin and thyroxine: The results assist in ruling out hypothyroidism and
hyperthyroidism.
Fasting glucose value, if prompted by signs or symptoms
Stool for occult blood in patients aged 40 years or older: A positive result
suggests possible malignancy in the GI tract.
HIV antibody test, if risk factors are present
Skin biopsy for routine pathology and immunofluorescence to exclude
subacute occult autoimmune conditions such as pemphigoid and dermatitis
herpetiformis
Imaging Studies
 In patients with Hodgkin disease, chest radiography
may help in detecting lymphadenopathy in the
mediastinum. If cholestasis is present, abdominal
ultrasonography may be performed to evaluate the
biliary tract.
• When the results of initial laboratory screening are
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negative and when the physician still suspects a systemic
cause, tests of the following may be ordered:
Serum protein electrophoresis
Stool for ova and parasites
Stool for occult blood (may reveal source for anemia)
Urine for hydroxy indole acetic acid (5-HIAA) and mast cell
metabolites
Negative findings from the initial evaluation do not
necessarily exclude systemic disease, and follow-up
screening may be repeated every 3-6 months if clinical
suspicion continues
 Skin biopsy for direct immunofluorescence and
special stains may help exclude a primary
dermatologic condition, such as dermatitis
herpetiformis or bullous pemphigoid (ie, pruritic
pemphigoid), or confirm a systemic cause, such as
in mastocytosis. Medical Care
Renal pruritus therapy
• Narrow band 6-8 session have response is choice and
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after
Gabapanthin
Cholestiramin
Nalteroxane
Capsaicin 0.025%
Tacrolimus 0.03% . Tacrolimus is a calcineurin inhibitor, it
decreases the differentiation of type 1 helper T
lymphocytes, and it reduces the production of interleukin
2.[13]
Topical gabapentin cream (3-6%)
Oral zinc sulfat 440 mg /day
Cholestatic pruritus
• Cholestiramin
• Rifampin
• Ursodeoxycholic acid and S-adenosyl-L-methionine have
both been reported to decrease pruritus in women with
cholestasis of pregnancy, but ursodeoxycholic acid may
improve fetal outcomes and biochemical serum markers.[39,
40]
• Extracorporeal albumin dialysis may be considered when
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severe pruritus is refractory to other therapies.[41, 42]
Thalidomide
uvb
• Iron deficiency responds to treatment with iron, which
should be continued until ferritin levels are
normalized
• Patients with pruritus due to polycythemia vera may
benefit from aspirin, which is considered the first-line
therapy. Cimetidine, danazol, cholestyramine, UV-B
light therapy, and psoralen with UV-A therapy have all
been shown to help.[43, 44]
 Endocrine pruritus
 The pruritus of hypothyroidism is secondary to xerosis
and should be treated with emollients and thyroid
hormone replacement. Pruritus secondary to
hyperthyroidism improves with the correction of
thyroid function.
Patient Education
. Instructions should include keeping the skin well
moisturized and avoiding excessive bathing in hot
water, low ambient humidity, use of alkaline soaps,
and exposure to irritating fabrics. For severe cases, the
patient can perform the soak and smear technique,
which is the process of hydrating the skin for 20
minutes prior to bedtime, followed by the application
of ointment to the wet skin.
• The itch-scratch cycle should be discussed, and
patients should be encouraged to apply cool
washcloths or gentle pressure to the areas and to resist
the urge the scratch. Reduction or elimination of
stressful factors should be discussed because stress
appears to worsen itching.