CM: Derm - Skin (Systemic and fungal) Infections Flashcards
Roseola (Other names)
Exanthem subitum or sixth disease
Roseola (cause)
Human herpesvirus (HHV-6)
Roseola (symptoms)
Sudden high fever lasting 3-5 days followed by an erythematous (morbilliform) maculopapular rash that begins on the trunk and spreads to the neck and legs lasting hours to days. No other symptoms.
Roseola (population)
Children 6 months to 4 years, most commonly under age 2 years
Rubeola (other names)
Measles
Rubeola (symptoms)
Fever accompanied cough, coryza (stuffy nose), conjunctivitis followed by a maculopapular rash that begins on the head and spreads to the trunk and extremities. May experience extreme lethargy, weakness, decreased appetite, difficulty breathing, and periocular edema.
Rubeola (unique characteristics)
- Koplik spots 2. Rash begins at hairline/ears and spreads head to toe 3. Rash leaves faint-brown stain after fading around day 6
Koplik spots
2 to 3 mm gray-white raised lesions on erythematous base of the buccal mucosa
Rubeola (communicated)
Airborne, often inhaled
Varicella (other names)
Chickenpox, shingles
Varicella (cause)
varicella-zoster virus (VZV) (HHV-3)
Varicella (shingles development)
Virus remains dormant in basal root ganglia until activated during a period of immunosuppression. Presents as neuropathic pain then rash that follows dermatomal patterns.
Varicella (rash cycle)
Rash evolves from papular (hard to see) to vesicular. Vesicles only last 4-6 hours before becoming pustular and rupturing to form a crust. Crust disappears in about 2 weeks.
Varicella (shingles unique characteristics)
Rash follows dermatomal lines (likely one sided)
Varicella (symptoms)
Fever, rash, headache, fatigue, loss of appetite, itching, sore throat
Hand-Foot-Mouth Disease (cause)
Coxsakievirus A16
Hand-Foot-Mouth Disease (communication)
Direct contact with body fluid (virus contained in saliva, tears and blister fluid)
Hand-Foot-Mouth Disease (Treatment)
Only supportive care
Varicella (Treatment)
Anti-viral medication, supportive care
Hand-Foot-Mouth Disease (symptoms)
Rash with vesicle lesions in the mouth (on the tongue and anywhere in the oral mucosa), palms of hands and feet Pain in lesions with older patients
Hand-Foot-Mouth Disease (immunity)
Immunity is developed with first exposure, will not reoccur
Fifth’s Disease (Name)
Erythema infectiosum, slapped-cheek disease
Fifth’s Disease (cause)
Parvovirus B19
Fifth’s Disease (population)
predominantly children 5-15 years old during winter and spring
Fifth’s Disease (transmission)
Respiratory secretions
Fifth’s Disease (symptoms)
Fever, respiratory symptoms and rash with “slapped cheek” appearance (fiery red maculopapular rash). Lesions will be warm and sometimes pruritic. Lesions will appear of extensor surface of extremities in 1-2 days and will involve the trunk, neck and buttocks. Palms/soles will be spared rash.
Fifth’s Disease (unique characteristics)
Extremely dangerous to pregnant women; can cause fetus to develop hemolytic anemia
Fifth’s Disease (complications)
Can cause the development of hemolytic anemia in children and fetuses Can cause development of arthritis in adults
Fifth’s Disease (immunity)
Immunity is developed with first exposure, will not reoccur
Fifth’s Disease (diagnosis)
Elevated IgM anti-parvovirus antibody
Impetigo (causes)
Staph. aureus or group A Strep. pyogenes
Impetigo (treatment)
systemic antibiotics and topical antibiotics, gentle debridement of crusts using antibacterial soap and HOT water
Impetigo (symptoms)
Honey colored crust, little to no pain
Erysipelas (other names)
St. Anthony’s fire
Erysipelas (cause)
Strep. A
Erysipelas (treatment)
Often need admission and IV antibiotics
Erysipelas (symptoms)
Edema, induration (palpable swelling), erythematic (looks like a burn), no distinct edges, enlarged lymph node
Erythrasma (cause)
Corynebacterium species
Erythrasma (diagnosis)
Coral-red fluorescence under Wood’s Lamp
Erythrasma (symptoms)
well-demarcated light brown to red-pigmented patch in hair-bearing or intertriginous areas
Erythrasma (treatment)
topical antibiotic (most common: clindamycin)
Lyme Disease (cause)
Borrelia burdorferi (spirochete)
Rocky Mountain spotted fever (cause)
Rickettsia rickettsii (Gram negative, coccobacilli/short bacilli)
Lyme Disease (cause host)
White-tailed deer host the adult tick, white footed mouse host larval and nymph stage
Lyme Disease (disease cycle)
Tick injects spirochetes into bloodstream. 3-32 days after tick bite, spirochetes replicate and migrate outward to skin, gives the erythema migrans “look” (targetoid rings)
Lyme Disease (unique characteristics)
erythematous nodule with marked inflammation and a punctate center (targetoid lesion)
Rocky Mountain spotted fever (symptoms)
Triad: tick bite, fever, rash (very uncommon)
Rocky Mountain spotted fever (rash cycle)
small pink macules that blanch - deep red papules that do not blanch - hemorrhagic papules/macules
EM
Erythema multiforme (bacterial)
TENS
Toxic epidermal necrolysis syndrome (bacterial)
SJS
Stevens-Johnson Syndrome (bacterial)
SSSS
Staphylococcal scalded skin syndrome (bacterial)
SSSS (unique characteristic)
Never involves the mucous membranes
EM (complications)
Can develop into TENS/SJS at any time
EM (Cause)
Drugs or viruses but can also be idiopathic
SJS (Rash cycle)
Starts with vesicles that look like target lesions but crust in the center. Before lesions progress, a very small vesicle forms then the fluid of vesicle will rupture and form a crust. During this time, the patient will complain of their skin hurting.
SJS (Treatment)
Lamictal or Bactrim
TENS (Unique characteristics)
More severe form of SJS that is classified by amout of body surface involvement 90% mortality rate
TENS (symptoms)
Niklosky sign, desquamation of skin
Niklosky sign
Skin finding in which the top layers of the skin slip away from the lower layers when rubbed
SSSS (cause)
Staph. aureus
SSSS (disease cycle)
Staph. aureus produces an exfoliative exotoxin (Exotoxin A&B). The serine proteases bind to the cell adhesion molecules and causes epidermolysis at the stratum corneum and stratum granulosum junction.
SSSS (population)
Newborns to 2-6 years (common in neonatal period)
Tinea Corporis (cause)
overgrowth of fungi that thrive on skin keratinocytes located on body
Tinea Cruris (other names)
Jock itch
Tinea Capitis (symptoms)
itchy scalp with patchy hair loss (though hair loss not required)
Tinea capitis (diagnosis)
pull hair from the center of the area of alopecia and lay hair in culture medium. The bulb of the hair contains greatest fungal yield
Tinea pedis (other names)
athlete’s foot
Tinea pedis (three types)
- Plantar mocassin type 2. Interdigital type 3. Vesiculobullis type
Tinea pedis (Vesiculobullis characteristics)
Most rare, secondary to aggressive T cell response to fungal elements, blisters and bullae
Tinea pedis (Interdigital characteristics)
Most common between D4 and D5. If maceration is present, likely fungal infection even if other symptoms are missing.
Tinea Manuum (other names)
two foot one hand disease
Tinea Manuum (symptoms)
rash uniformly on one hand (and commonly on feet, particularly between toes and on soles)
Tinea versicolor (other names)
pityriasis versicolor
Tinea versicolor (cause)
Malassezia furfur (normal flora that overgrows) interferes with melanocyte function due to overreaction of immune system
Tinea versicolor (symptoms)
hypopigmented oval patches located on the chest, neck and back
Tinea versicolor (treatment)
UV light (improves pigmentation)
Tinea versicolor (diagnosis)
KOH (sodium hydroxide test) will appear as broad hyphae with budding clusters of cells
Tinea versicolor (unique characteristics)
“spaghetti and meatballs” appearance on KOH
Candidiasis (other names)
Monilia
Candidiasis (cause)
overgrowth of normal yeast (commonly Candida Albicans) flora
Candidiasis (symptoms)
Beefy red rash with multiple satellite regions commonly in the groin, axilla, underneath breasts and between abdominal flaps
Candidiasis (diagnosis)
KOH shows pseudo hyphae fee with budding spores
Onychomycosis (cause)
Fungal elements invade keratin of nail itself and remains there
Tinea capitis (treatment)
Must be treated with oral anti-fungal medication
Onychomycosis (unique characteristics)
If infecting fingernails, generally involves all ten. If infecting foot, can involve just one or two.
Onychomycosis (treatment)
Topical antifungal; if in the foot, treat tinea pedis first then onychomycosis
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Roseola
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Varicella
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Rubeola
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Koplik Spots
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Hand-Foot-Mouth Disease
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Toxic Epidural Neurolysis
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Staphylococcal Scalded Skin Syndrome
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Lyme Disease
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Impetigo
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Candidiasis
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Erythema Multiforme
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Erysipelas
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Erythasma
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Rocky Mountain Spotted Fever
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Fifth’s Disease