1. Bites and Stings

2. Question 5
The most effective treatment to eliminate the lesions seen here:
A Topical steroids
B Oral antibiotics
C Treatment of home for fleas
D 5% Permethrin cream to all household members
E Oral antihistamines
Answer: D
Papular urticaria

3. Bites and Stings Think about distribution (exposure)
Bites on face may be atypical
Red
Pruritic
Soft and nontender
Intense, hemorrhagic reaction possible
Fleas: some members of household “spared”
Clusters of 3
Grass or sand mites: localized blisters

4. Spider Bite More intense reaction Erythema and induration Vesciculate
Ecchymotic
Painful
Pruritic
Vesciculate
Central necrosis with eschar
Brown Recluse

5. Hymenoptera Stings Local pain, erythema, edema within 2hrs Honey Bee
Stinger in skin
Releases venom for an hour
Scrape horizontally with fingernail or card

6. Hymenoptera Stings Late onset edema Treatment Risk of anaphylaxis
Peak 48-72hrs
Delayed hypersensitivity
Pruritic, painful
Treatment
Paste of meat tenderizer and water
Symptomatic treatment
Risk of anaphylaxis
Known history
Mastocytosis
Education on avoidance
EpiPen

7. Papular Urticaria Timing Description Young children Chronic/recurrent
Highly pruritic papules and wheals
Central punctum
Vesiculate centrally
3-10mm diameter
Resolution:
central crust with collarette of scale
After 4-6wks: target-shaped macule
Linear or triangular clusters
Exposed areas

8. Papular Urticaria Cause Only youngest child in family may be affected
Hypersensitivity to fleas, bedbugs, mosquitoes
Fleas and bedbugs are not seasonal
Only youngest child in family may be affected
>1y/o
May experience “reactivation”
New bites incite delayed hypersensitivity at old sites

9. Papular Urticaria Treatment Identification and avoidance of insect
Repellent
Topical steroids
Oral antihistamines
Good hygiene (secondary infections)

10. Infestations

11. Scabies Cause Timing Description Mite: Acarus scabiei
Burrows beneath skin
Hypersensitivity reaction
Timing
4-6 wks after initial contact
Description
Intensely pruritic papules, vesicles, pustules, linear burrows
fingers/ webs of toes, flexor regions, nipples, waist, groin/buttocks, palms/soles
Infants: intense and persistent nodular reaction

12. Scabies Excoriation and secondary infection Diagnosis Treatment
Clinical
Skin scrapings: mite, eggs, feces
From linear burrow (black speck)
Treatment
5% permethrin (Elimite)
All household members
Wash all linens
Repeat 1 wk later

13. Lice Crab lice (Phthirus pubis) Sexually transmitted
Eyelashes and pubic hair
Bites
Bluish, pruritic papules: lower abd and upper thighs
Intense pruritis
Children
Scalp or eyelashes

14. Lice Body lice (pediculus humanus corporis) Bedding or clothing Bites
Urticarial papules
Waist, neck, shoulders, axillae
Excoriations/ secondary infection

15. Lice Head Lice (pediculus humanus capitis)
Most common
Excoriations of scalp and neck
Occipital adenopathy
Nits: oval, white 0.5mm dot glued to hairshaft
Above and behind ears
Nonviable shells may remain attached after treatment

16. Lice Treatment: Pediculicide topically (all household members)
Permethrin cream
Malathion lotion (second line…flammable)
Lindane: contraindicated in young… neurotoxic
Cleaning of linens/clothing
Nits:
Diluted vinegar rinse
Fine-toothed comb

17. Acne Acne vulgaris Cause: Unknown Treatment
Disorder of pilosebaceous apparatus
Cause: Unknown
Abnormal follicular keratinization
Driven by androgens
Propionibacterium acnes
Treatment
Topical retinoic acid, benzoyl peroxide, abx
Severe: oral abx with topical agents
Beware retinoic acid in preganancy

18. Other Lesions

19. Question 6
The most reliable way to distinguish these lesions from other lesions frequently seen on the sole of the foot:
A Black dots indicate corns that have received trauma
B Interruption of dermatoglyphics indicate plantar warts
C Superficial scaling indicates callus formation
D Boggy texture indicates plantar warts
Answer: B
Plantar Wart

20. Warts HPV Fingers, hands, feet Plantar wart: Larger than appearance
Painful w walking
Interrupts dermatoglyphics
Incubation 1-6mos
Disappear spontaneously over 5yrs
Local trauma: inoculation of virus
Periungual common
Calluses and corns do NOT interrupt dermatoglyphics

21. Warts Characteristic appearance Condylomata acuminata Treatment
Black dots (thrombosed capillaries)
Condylomata acuminata
Anogenital warts
Consider sexual abuse
Controversial <age 3 (vertically acquired)
Treatment
Duct tape
Salicylic acid

22. Molluscum Contagiosum
Pox virus
Description:
Dome-shaped papules with waxy surface
Single or multiple
May be pruritic
5mm
Location: trunk, face, axillae, genital area
Spread by scratching (linear)

23. Molluscum Contagiosum
Curdlike core can be expressed from center
Course: spontaneous remission 2-3yrs
Treatment
Watchful waiting
Curetting after topical anesthetic
Especially in poorly controlled eczema

24. Congenital Lesions

25. Cutaneous mastocytosis
Pathological proliferation of mast cells in skin
Other organs involved as well
Darier sign
When lesion (or skin) rubbed, urticaria develops
Histamine release following trauma to superficial mast cells
May form blisters
75% identified by age 2

26. Cutaneous mastocytosis
Urticaria pigmentosa
(most common form)
Oval or round red-brown
Macules, papules, plaques
Solitary or innumerable
Resemble
Nevi, pigmentary alteration, CALMs
May be associated with GI symptoms
Hypotension in severe cases

27. Cutaneous mastocytosis
Other organ systems can be affected
Treatment
Usually resolves in childhood
Symptomatic treatment
Antihistamines
Immunosuppresants in severe cases
Extensive workup rarely needed

28. Juvenile Xanthogranuloma
AKA: Nevoxanthoendothelioma
Present at birth (w/in 1st year)
Grow slowly and become more yellow
Benign proliferation of non-Langerhans cell histiocytes
Brown to yellow color: lipid-laden histiocytes
Benign

29. Juvenile Xanthogranuloma
Primarily in whites
Usually solitary nodular lesion
Multiple small papular lesions possible
4% extracutaneous
Iris
Other locations
Associations/Complications
Glaucoma
Myelomonocytic leukemia
Nontraumatic Hyphema

30. Juvenile Xanthogranuloma
No specific gene defect
NF-1
Urticaria pigmentosa
Niemann-Pick
Treatment
Watchful waiting
Resolve 5y/o
Surgical excision
Steroids +/- chemo

31. Job Syndrome Abnormal immunity Chromosome q4 T-Cells, Neutrophils
High IgE and eosinophils
Chromosome q4 AD
Variable expressivity

32. Job Syndrome Description Timing Pruritic S. aureus superinfection
Weeping, crusting, cutaneous abscesses
Abscesses (little pain and inflammation)
Mucocutaneous candidiasis
Timing
Shortly after birth

33. Job Syndrome Course Treatment Recurrent focal bacterial infections
Decreased bone density with multiple fractures
Little pain
With age: scoliosis and coarsening of facial features
Treatment
Control infections