parasitic, fungal, nail, and bacterial infestations

Question 1

scabies

Answer 1

mites burrow under the skin and lay eggs
transmission via close personal contact

s/s: intense itchiness worse at night & rash - interdigital web spaces, wrists, axillary folds,

primary - small 1-2mm red papules, intradermal linear burrow, may have excoriation, crusting, and scaling

secondary bacterial infection

dx - clinical

tx - permethrin cream 5%, topical corticosteroid for pruritis

Question 2

pediculosis (lice)

Answer 2

s/s - asymptomatic, may have pruritis localized to head or pubic region, sensation of “crawling”

small 2-3 mm red macule or papules, many have hives or nits on hair shafts

dx - clinical

tx - topical pediculicide (permethrin 1%, Nix OTC)
nonpharm- occlusive agents to suffocate lice, manual removal, environmental control (wash clothes and brushes)

Question 3

beg bugs

Answer 3

small, flat, parasitic insects that feed on humans
reddish-brown can live for months

transmission via clothing or luggage

s/s- maculopapular with a central punctum - curved line composed of 3 bites, pruritis

tx - hydrocortisone & antihistamine for itching, eradication (hot water, chemical insecticides)

Question 4

tinea capitis

Answer 4

fungal infection of the scalp
contact transmission

areas of alopecia with swelling and erythema

dx - clinical, fungal cx, KOH exam

tx - oral Lamisil or Gris-PEG in children; oral or topical steroids may be necessary for nodule

Question 5

tinea corporis

Answer 5

dermatophyte infection of the trunk, legs, arms, and/or neck
human or animal contact

pink patches with clearing, central cleaning or red border

dx - KOH exam

tx - topical antifungals

Question 6

Tinea cruris

Answer 6

fungal infection in groin
post-pubertal men, worsened by heat, humidity, friction

dx - clinical & KOH exam

tx - remove exacerbations, Zeasorb-AF maintenance powder, topical anti fungal

Question 7

Tinea pedis

Answer 7

fungal infection between toes

dx - clinical & KOH exam

tx - topical antifungals, systemic antibiotics for secondary infx

Question 8

tinea versicolor

Answer 8

superficial infection of the skin with yeast

tx - selenium sulfide shampoo, systemic tx for more severe infections (fluconazole)

Question 9

oncholycosis

Answer 9

commonly associated w tinea pedis

s/s - brown/yellow discoloration of nail, thickening and separation from nail, white patches on nail

dx - fungal culture

tx - topical agents, or systemic meds (Lamisil)

Question 10

impetigo

Answer 10

common skin infection in children, very contagious

transmission through contact (contagious!)

staph and strep

s/s - honey-colored crusted plaques with scales, redness, itching, burning, pain

dx - clinical

tx - mupirocin topical, oral abx for most severe; avoid contact w others

Question 11

cellulitis

Answer 11

infection of the dermis and SQ tissue

s/s - erythema, edema, pain, plaque w indefinite boarder
fever, chills, HA, malaise

staph, strep, H. flu

dx - clinical, wound culture or BCx, leukocytosis

tx - dicloxacillin, augmentin, cephalexin

MRSA - culture, bactrim, minocycline, doxy, rifampin, Zyvox, vanco, hygiene!!!

Question 12

erysipelas

Answer 12

cellulitis resulting from GABHS

sharp margins

tx - PCN, azithromycin, biaxin, cleocin

Question 13

folliculitis

Answer 13

infection of hair follicles

s/s - perifolicular papule/pustules, itching, pain around hair follicle

can progress to furunculosis

tx - PO abx, avoid irritants

Question 14

feruncle/ferunculosis

Answer 14

deep infection of the hair follicle leading to abscess formation

s/s - red, swollen, tender nodules on hair-bearing parts of the body, may form carbuncle

dx - clinical, bacterial culture if needed to ID agent

stap, MRSA