Blisters, Exanthems, and Bites Flashcards
What is a blister
-A painful (most of the time) skin condition where fluid fills a space between the dermis and epidermis
-common blister on the epidermis
-Also known as a Bulla
-Burns
-Friction injuries
-Cold
-Reaction to irritants
-Drug reactions
bullous pemphigoid epidemiology
-Auto immune blistering eruption
-Elderly (mean age 64-80)
-Pre-existing neurological diseases (dementia, Parkinson’s epilepsy…)
-Associated with production of autoantibodies targeting the basement membrane zone (BMZ)
-BMZ important in attaching the epidermis to the dermis
-Crates a space between these two and TENSE blisters form
-you can see this blister bc its formed at a lower base
-Before Bullae form, can present with puritic urticarial rash
bullous pemphigoid
-Blisters are commonly bilateral, symmetric, on the trunk and proximal flexural extremities
-clinical dx
-When performing a biopsy, edge of an intact bullae
-Direct immunofluorescence (DIF)- normal skin and edge of blister shows deposit of IgG (antibody found in bullous diseases) along basement membrane
-Other things can mimic- histo pathology and DIF necessary
management of bullous pemphigoid
-Can be a chronic relapsing disease
-Can spontaneously resolve
-Tense bullae can be drained with sterile needle
-Treatment depends on severity
-antibiotics are used for anti-inflammatory (Not anti bacterial)
-Mild – Topical steroids and Oral Tetracyclines
-Moderate –Severe- Oral Steroids methotrexate
key components of bullous pemphigoid
-TENSE Blisters… YOU SEE THEM!
-Elderly
-Associated Conditions-Parkinson’s, Dementia, Epilepsy
-Look for words… Auto antibodies… Basement membrane zone (BMZ)
pemphigus vulgaris
-Rare Blistering disease of the skin and muscus membranes
-Older Patients (range- 38-72)
-Associated with autoimmune diseases such as Thyroid Disease, Myastania Gravis, Sjogren’s and RA
-Superficial Blisters* often present as crusted erosions or flaccid blisters
-guttate distribution
-Some present with only oral mucosa involvement*
-Typical areas are head upper trunk, and intertriginous zones
-Positive Nicolsky sign** - push on blister and twist -> blister will disintegrate
-differentiates between tense and erosive blister
-by the time the pt comes into office the blisters are usually bursted
-itching and pain
pemphigus vulgaris management
-Diagnosis made with 2 biopsies-from edge of blister and DIF (Direct Immunofluorescence) from edge of blister with normal skin
-Mild disease treated with topical steroids- gel based for mucosal lesions or swish and spit solutions.
-Moderate to severe disease- oral steroids short or long term, Rituximab, methotrexate
-WATCH FOR INFECTION! (bc its superficial)
key factors of pemphigus vulgaris
-Gus+Nicholsky has bad breath
-PemphiGUS
-Positive Nicholsky sign
-Usually found in mouth
dermatitis herpetiformis
-rash
-typically older pts but can be in younger
-autoimmune
-skin manifestation of celiac disease (pts cant have gluten)
-IgA antibody is found in this disease and celiac
-it can be associated with celiac but also separate
-vesicular rash *
-clusters
-itchy
-tiny little bubbles initially, but pts scratch it
-excoriations
-GI issues
-thyroid disease, diabetes, connective tissue disease
viral exanthem
-Prodromal Fever, sore throat, and then Rash
-Described as papular or maculopapular
-Note color, primary lesion, presence of desquamation and swelling, and distribution pattern can help to diagnose
-Sandpaper -5ths disease
-dew drop on a rose petal - chicken pox
-Respiratory MC in winter
-Enteroviruses MC Summer
evaluation of viral exanthem
-History history history
-Ask the questions…
-If still perplexed, blood work, PCR, Tzank smear
hand foot and mouth disease
-A mild, highly contagious viral infection caused by Coxsackie Virus (A16 is most common)
-Macular rash starting on palms, feet, sometimes buttocks. Rash progresses to vesicles
-Throat is usually involved
-Lesions can be painful
-Malaise, Irritability, HIGH fever, sore throat, loss of appetite, headache
-Spread by respiratory droplets, close contact, saliva, fluid from vesicles and fomites
-Generally children <10years old but adults can get it too!
-think- water parks
treatment of HFM aka coxsackie
-Stay hydrated- most important!
-Treat the Pain with Tylenol or Advil
Pityriasis Rosea
-viral rash
-Usually no symptoms, just a rash
-May have had a previous illness
-Gutate** (splattered) erythematous papule with a trailing scale
-Herald Patch- 1st sign -> biggest area*
-Christmas tree distribution on back*
-Lab tests not indicated
-Clinical diagnosis
-body is responding to a virus -> rash manifestation
-tx- Self limiting, Topical steroids if rash is itchy
bites- spider
-Most spider bites do not cause any harm
-Looks like any other insect bite
-Inflammation soreness sometimes itchy from histamine release
black widow spiders
-Redness pain or swelling that can spread to the abdomen chest or back
-Abdominal rigidity and or cramping
-Nausea, vomiting, chills, headache, tremors or sweating
-Symptoms appear quickly
-Symptoms can last 1-3 days
-Treated with muscle relaxants, pain medication, and sometimes in extreme cases as a last resort
->antivenom- we dont use a lot bc it can cause anaphylaxis
-can sometimes see 2 fang marks
-usually more serious for children
brown recluse spider
-Initially bite appears red
-May develop into a blister
-Ulceration* may occur if left untreated
-Can cause cell necrosis within 4 hours
-Blue halo around puncture*
-Bites have dark flat centers
-more serious
-Symptoms appear in 1-2 days
-Pain or redness at the site
-Fever, chills, nausea, weakness, joint pain
brown recluse spider tx
-If a child gets bit, seek immediate medical attention
-Most adults can handle the bite without medical attention
-Clean with soap and water
-Antibiotic ointment
-OTC pain medication
-Ice and elevation
-Possible tetanus shot (some spiders carry tetanus spores)
scabies epidemiology
-Parasitic infection Sarcoptes Scabiei
-Transmitted from person to person by direct skin contact (or fomites)
-Completes its 30 day life cycle within the epidermis
-Leaves a trail of eggs and feces
-highly contagious
scabies S&S, treatment
-Rash is from a hypersensitivity reaction to the mite
-Presents with intense puritic papules on the hands, wrists, arms, trunk and genitals
-Short wavy red line (burrow*) is a telltale sign
-intense itching- can cause lack of sleep
-Severe itching that worsens at night
-Biopsy, Dermoscopy, tape pull
-Treat with Permethrin “neck to toe” 8-14 hrs -> repeat 1 week later
-can reoccur- psychological component as well
head lice pediculosis capitis
-Bloodsucking, wingless insects
-Head, crab and body lice
-Head lice MC
-Parasites that feed on human blood
-Size of a sesame seed
-eggs are sticky
-Direct contact (head to head)
-Fomites hats, combs brushes head phones
-Move quickly
-Female has a 30 day life cycle and lays 5-10 eggs a day
-Discard infested clothing, bed linens or wash 149 degree water
-Treat head with Permethrin (nix)for 10 min. Repeat in 7-10 days preg cat b
-Ivermectin –leave on 10 min rinse can be repeated 1 week preg cat C
-Nit combs to remove un hatched eggs
bed bugs- cimex lectularius
-4 star hotels to homeless shelters!
-Blood sucking Parasitic arthropods-
-Brown, oval, wingless
-Size of an apple seed
-Attracted to heat and carbon dioxide
-Feed on exposed skin
-Hide during day- feed at night
-Survive up to a year without a blood meal
-Disease vector- 45 pathogens HepB, HIV, Staph
-Linear or clustered groups of 3 “breakfast lunch and dinner”
-Eradicate source
-Treat with oral antihistamines, topical steroids, antibiotics if necessary
measles, mono, varicella, rubella, varicella, roseola, parvovirus, scarlet fever, toxic shock syndrome***, RSMF
