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MAJOR MANIFESTATION OF SKIN DISEASE
By :Dr .Pawana Kayastha
SKIN CHANGES IN OLD AGE
•Typical changes: include atrophy, laxity, wrinkling, dryness, irregular pigmentation and sparse grey hair. •changes are brought about by: age-related alterations in structure and function of the skin
•cumulative effects of environmental insults, especially ultraviolet radiation
•cutaneous consequences of disease in other organ systems
•Immunity: alterations in immune surveillance and antigen presentation, and reduced cutaneous vascular supply which lead to decreases in the inflammatory response, absorption and cutaneous clearance of topical medications.
•Consequences: these changes make the skin less durable, slower to heal, and more susceptible to damage and disease.
COMMON SKIN DISEASES IN OLD AGE
•Prevalence: about 40% of individuals over the age of 60 years have significant dermatological problems.
•Diseases: the most common in this age group are:
• skin cancers • leg ulcers, a major cause of morbidity in the
elderly • blistering disorders• herpes zoster (shingles) and post-
herpetic neuralgia
.
inflammatory skin diseases, e.g. asteatotic, gravitational and seborrhoeic eczema, psoriasis
lichen sclerosus et atrophicus scabies lymphoedema pruritus of old age drug-related rashes
THE CHANGING MOLE
Long standing pigmented spot.
The principal clinical concern is to distinguish correctly between benign pigmented lesions and melanoma.
The situation is complicated by the fact that any one of a number of changes in a pigmented lesion is highly sensitive as a marker of melanoma, specificity is low.
'IS IT CANCER, DOCTOR?'
ABCDE FEATURES OF MALIGNANT MELANOMA
Asymmetry Border irregular Colour irregular Diameter often greater than 0.5 cm Elevation irregular
(+ Loss of skin markings)
HISTORY Determine the precise nature of the
change. Is it due to the development of itch, inflammation, bleeding or ulceration, or does it relate to the colour, size, shape or surface of the lesion?
Subtle changes:plucking hair,shaving,irritants
Is the patient worried about change in one or many moles?
Positive family history of melanoma. Fewer than 10% of melanomas occur in individuals with a strong family history but in some of these families up to 50% of individuals may develop melanoma.
EXAMINATION Examine the pigmented lesion carefully. Look at the morphology of the
melanocytic naevi at other sites. magnifying glass or dermatoscope whether the lesion is a benign
melanocytic naevus or a malignant melanoma
Before trying to answer this, the clinician needs to exclude the possibility that it is another type of pigmented lesion: Lentigo (a benign proliferation of
melanocytes) Freckle (ephelis, a focal overproduction of
melanin,)
Seborrhoeic wart (basal cell papilloma, a benign keratinocyte tumour)
Dermatofibroma. This lightly pigmented firm dermal nodule is common on extremities in young adults. It feels larger than it looks. There is dimpling when the skin is squeezed on both sides (positive Fitzpatrick sign).
Pigmented basal cell carcinoma : This lesion is usually found on the face of the elderly and is slow-growing. It has a blue-brown hue with an opalescent look. There may be a rolled edge around an ulcer.
Subungual haematoma
MANAGEMENT Any changing lesion which is suspected of being
a malignant melanoma should be excised without delay, with a clear margin.
If there is even a low index of suspicion of a
malignant melanoma ,then the lesion should be reviewed 1 month and may be 3mths later.Continuing change demands excision.
If benign then reassurance but advised to report back without delay if the change and concern continue
If in doubt cut out and then check the histology
PRURITISAn unpleasant localized or generalized
sensation on the skin, mucus membranes or conjunctivae which the patient instinctively attempts to relieve by scratching or rubbing
DIVERSITY OF CAUSES AND PRESENTATIONMany Causes, Many Treatments
Trivial to Life threatening
(mosquito bite) (malignancy)
10-50% of cases with generalized itching have systemic disease
DISEASES & ITCHING
Skin diseases associated with generalised pruritus
Eczema Scabies Urticaria/dermographism Pruritus of old age and xeroderma
Skin diseases associated with localised pruritus
Eczema Lichen planus Dermatitis herpetiformis Pediculosis
CAUSES OF PRURITUS iin IN PREGNANCYCondition
Gestation and features Treatment
Obstetric cholestasis
3rd trimesterAssociated with abnormal liverfunction tests
EmollientsChlorphenamineColestyramineEarly delivery
Pemphigoid gestationis
3rd trimesterPruritus followed by blisteringStarts around the umbilicus
Topical or oral corticosteroids
Polymorphic eruption (urticarialpapules) of pregnancy
3rd trimester, after deliveryPolymorphic lesions with urticaria
Chlorphenamine
IN PREGNANCY
Prurigo gestationis
2nd trimesterExcoriated papules
EmollientsTopical corticosteroidsChlorphenamine
Pruritic folliculitis
3rd trimesterAseptic pustules on trunk
Topical corticosteroids
RENAL DISEASES AND ITCHING Chronic Renal Failure: 25-86% itching (not in acute renal failure)
Attrib to accumulation of pruritogens:
histamine (mast cells), serotonin Ca, Phos, Mg, Al, vit A also implicated
1/3 uremic patients not on dialysis Maintenance hemodialysis: 70-80%
HEPATIC DISEASES & ITCHING 20-25% janudiced patients with
hepatobiliary disease associated with cholestasis100% primary biliary cirrhosisViral hepatitis
Attrib to bile salts in serum and tissues Begins palms and soles & spreads
inward
HEMATOLOGIC DISEASE & ITCHING Polycythemia vera (50%) iron def anemia, lymphomas
Hodgkins – 30% T-cell: almost all
leukemias, plasma cell dyscrasias, mastocytosis
NEUROLOGIC DISORDERS & ITCHING Central: CNS abscess, spinal and
cerebral tumors (17%), CVAsAttrib to effects on descending pathways
which itching Neurogenic
Shingles (10-15% in US)Notalgia paresthetica: sensory entrapment
syndrome causing neuropathy of T2-6 dorsal spinal nerves
ENDOCRINE D/O & ITCHING Diabetes Thyrotoxicosis,Hypothyroidism Generalised due to dry skin
Localised may be due to Candida Myxodema Postmenopausal syndrome
Most common trigger: mucocutanious candidiasis
HIV infection Infection, infestationEosinophilic folliculitisUnknown
Malignancy Unknown
Psychogenic Unknown
CHEMICALLY INDUCED ITCHING:
NEUROAXIAL opioids commonly
Direct action on medullary dorsal horn and trigeminal nucleus of medulla – not t/histamine release
Spinal anesthesia with lidocaine: 30-100% pruritis
Fentanyl: Intrathecal 67-100%Epidural 67%
Morphine Intrathecal 62-82%Epidural 65-70%
CHEMICALLY INDUCED ITCHING:ANTIBIOTICS Penicillin: immediate type I
hypersensitivity reaction Vancomycin: massive
nonimmunologic release of histamine “Red Man Syndrome” (flushing CP, pruritis, muscle spasms,
hypotension)Related to rate of infusionPotentiated by muscle relaxants and opioidsAttenuated by H1 blockers
Rifampin
CHEMICALLY INDUCED ITCHING:OTHER DRUGS Fentanyl: itching decreased when mixed
with bupivicane, increased when mixed with procaine
Drug induced cholestasis esp phenothiazenes, estrogens,
tolbutamide, anabolic steroids
HISTORY & EXAMINATION
LOOK for skin changes If no skin disease identified then search for
systemic diseases by systemic examination
Investigation –as per systemic illness
PRURITOGENIC STIMULI Pressure Low-intensity electrical Histamine: acts directly on free nerve
endings in skin
ITCH MEDIATORS Histamine Prostaglandins Leukotrienes Serotonin Acetylcholine
Substance P Proteases Peptides Enzymes Cytokines
ITCH PATHWAYS Cutaneous (pruritoceptive) Neurogenic Neuropathic Mixed Psychogenic
ITCH PATHWAYS C-Fibers originate @ dermal/epidermal jxn
Thin unmyelinated axons, lots of branching
Ipsilateral dorsal horn of spinal cord Synapse with itch-specific secondary
neurons Cross to opposite anterolateral
spinothalamic tract to thalamus Somatosensory cortex of postcentral gyrus SLOW transmission and BROAD receptor
field
LATERAL INHIBITION: “GATE THEORY” Scratching stimulates large fast-
conducting A-fibers adjacent to slow unmyelinated C fibers
A-fibers synapse with inhibitory interneurons and inhibit C-fibers
Scratching may either–stimulating ascending sensory pathway-inhibit itch at the spinal cord Or,may damage itch fibers directly
PAIN & ITCH Painful stimuli (thermal, mechanical,
chemical) can inhibit itching Inhibition of pain (opioids) may enhance
itching
HOW TO TREAT AN ITCH(UNDERSTAND THE CAUSE!) Inhibit mediators of itch: histamine,
prostaglandins, substance P, serotonin, cytokines
Block chemicals that induce pruritis: opioids, antimicrobials
Treat effects of diseases which induce itching: eczema, CRF, LF, heme, neuro, endo
ECZEMA & ITCHING: TREATMENT cool compresses emollients topical steroids antidepressants anxiolytics antibiotics
RENAL DISEASES AND ITCHING Tx for uremic itching: renal transplant
Effective even when transplant is failing as long as immunosuppresants are given
Antihistamines not effective Also effective: moisturizers, UV-B tx
(vit A in skin), oral activated charcoal, cholstyramine, naltrexone, ondansterone, topical capsaicin, azelastin, thalidomide, IV lidocaine, erythropoetin, electric needle stim
HEPATIC DISEASES & ITCHING Tx: reverse cholestatis, liver transplant Also helpful: oral guar gum (dietary
fiber) binds bile acids; cholestyramine; rifampin! (inhibits bile uptake), opioid antagonists, codeine, propofol, ondansetron,NaltrexoneUVB
Not helpful: scratching
OTHERS Thyrotoxicosis Emollients Lymphoma Cimetidine Iron defn Iron supplement HIV
Treatment of opportunistic infectionLocal corticosteroids, UVBUVB
Pshychogenic PsychotherapyAnxiolyticsAntidepressives
opioid related pruritis : Diphenhydramine – for systemic
opioids For Neuraxial Opioids:
Ondansteron Naloxone (1-2mcg/kg/hr)Nalbuphine (10-20 mcg/kg/hr) Propofol (.5-1mg/kg/hr)Lidocaine (2mg/kg/hr)NSAIDs (diclofenac, tenoxicam)Droperidol
Penicillin ReactionDiphenhydramine
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