Pruritis and Dysthesia

Question 1

Name non-dermatological conditions with generalised pruritis

Answer 1

Question 2

Classify of pruritus (3 large groups)

Answer 2

Question 3

Ethologies of pruritus

Answer 3

Question 4

Important things to check on patient history with generalised /localised pruritus

Answer 4

1) Acute onset with no primary skin lesions - suggest systemic d/o
2) lesions on mid upper back suggest primary skin d/o (difficult to reach - butterfly sign )
3) medication including otc, drugs
4) urticaria
5) pruritus after bath - polycytemia Vera, idiopathic aqaugenic pruritus
6) nocturnal pruritus and sweating/chills -lymphoma
7) scabies (multiple fam members)

Question 5

What is dysthesia?

Answer 5

abnormal sensation
burning/tingling/numbness
due to
1) abnormal CNS (neurogenic) - locoregional
2) abnormal nervous system (neuropathic) localised

Question 6

1st line exams for generalised pruritis

Answer 6

do exam: skin, mucous membrane, scalp hair, nails, anogenital. primary/secondary lesions, signs of systemic disease (LN, HSM)
1st line special investigations
esr, fbc, u+cr, liver transaminase, ALP, bili, LDH, thyroid fc

Question 7

2nd line examinations for pruritus

Answer 7

HBA1C
s-iron
stool for occult blood
cxr/ct
skin biopsy
HIV/hep screen
serum IgE
prick/patch test
anti-sm antibody

Question 8

Pruritis in dermatologic disease

Answer 8

Question 9

Key facts about pruritis in atopic dermatitis

Answer 9

Question 10

Key facts on pruritus in Cutanoeus T cell lymphoma

Answer 10

Question 11

Name 3 dermatosis that result from pruritis and associated behaviour

Answer 11

1. Prurigo nodularis
2. Lichen simplex chronicus
3. Lichen ruber monilliformis

Question 12

Discuss prurigo nodularis in terms of
Pathogenesis
Clinical features
Diff dx
Histologic
Treatment

Answer 12

Also add at treatment: capsaicin, cryotherapy

Question 13

Discuss lichen simplex chronicus

Answer 13

Question 14

Lichen ruber moniliformis

Answer 14

Question 15

Name pruritic variants

Answer 15

Question 16

Name the criteria for ideopathic aquagenic pruritus

Answer 16

also increase dermal/epidermal Ach, histamine, serotonin, PGE2

Question 17

Treatment of aqaugenic pruritus

Answer 17

Also: adding bicarbonate to bathwater (alkalinization - pH of 8)

Question 18

Diff dx of aquagenic pruritis

Answer 18

Question 19

Differential diagnosis of pruritus after water contact

Answer 19

Question 20

Describe the etiology and clinical features of pruritis ani

Answer 20

Question 21

Histology of pruritus ani

Answer 21

Non specific dermatitis
Exclude - lichen sclerosus and malignancy eg pagets

Question 22

Treatment of pruritus ani

Answer 22

Question 23

Etiology of pruritis vulvi and scroti

Answer 23

1) acute - often infectious or irritant contact dermatitis
2) chronic dermatosis (AD, psoriasis, LP, Lichen sclerosus,
3) malignancy - pagets/scc
4) atrophic vulvovaginitis
5) other: pysogenic (1-7%)

Question 24

Treatment of pruritus vulvi and scroti

Answer 24

Cleansing and toilet habits
Treat underlying cause
Similar to pruritus ani

Question 25

Describe scalp pruritus

Answer 25

related to skin disorder (dermatomyositis, seb derm, psoriasis) or not (stress, fatigue) rx: emollients, tcs

Question 26

Name key facts on pruritus in scars

Answer 26

Question 27

Name key facts on post burn pruritus

Answer 27

Question 28

Name key facts on fibreglass dermatitis

Answer 28

Question 29

Name key facts on psychogenic pruritus

Answer 29

Question 30

Name most common pharmacological causes of pruritus and its mechanism

Answer 30

Question 31

Name key features of Brachioradial pruritus

Answer 31

Question 32

name key feautuees of burning mouth syndrome

Answer 32

Question 33

name key features about burning scalp syndrome

Answer 33

Question 34

name key features of notalgia parasthetica

Answer 34

Question 35

Name key features if meralgia parasthetica

Answer 35

Question 36

name key features of dysesthetic anogenital pain syndrome

Answer 36

Question 37

Name key features of trigeminal neuralgia

Answer 37

Question 38

name key feutures of trigeminal trophic syndrome

Question 39

Name key features of reflex symphatetic dystrophy

Answer 39

Question 40

describe renal pruritus and its treatment

Answer 40

Question 41

describe cholestatic pruritus

Answer 41

Question 42

describe hematologic priritus

Answer 42

Question 43

describe endocrine pruritus

Answer 43

Question 44

describe pruritis in HIV

Answer 44

can develop many pruritic dermatoses ppe, ef, seb derm, drug eruption, ks, prone to develop rf, nhl, liver disease pruritus often resistant to RX (increae IgE, hypereosinophilia, Th2 cytokines) increae VL = intractable pruritus treatment: treat underlying disorder, topical cs, UVB, anti histamines for symptomatic and anti-eosinophilic effect. ART can improve pruritic skin condition or can cause flare (IRIS), Thalidiomide option in pruritus and HIV, prurigo nodularis (not an immunosuppressant) 100-300mg/day

Question 45

approach to Treatment of pruritus in dermatology

Answer 45