Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
36 Cards in this Set
- Front
- Back
|
Usual flora of skin
|
gram positive cocci: staph, strep
|
|
|
skin cells packed tightly, so what kind of bacteria may grow on them?
|
anaerobic bacteria
|
|
|
Dandruff producing yeast
|
pityrosporum ovale
|
|
|
Types of skin lesions
|
Vesicles → small fluid-filled lesions
Bullae → vesicles larger than 1cm Macules → flat, reddened lesions Papules → raised lesions Pustules → raised lesions containing pus |
|
|
Types of staph skin infections
|
-Gram positive cocci (catalase positive)
-Staphylococcus aureus (coagulase positive / pathogenic) -Staphylococcus epidermidis (coagulase negative / comprise the majority of skin microbiota) -Pathogenic S. aureus produce enterotoxins, leukocidins, exfoliative toxins, etc. |
|
|
Staph infections
|
Most S. aureus are resistant to penicillin (produce penicillinase) and are treated with vancomycin
Localized infections: sties, pimples, carbuncles Impetigo of the newborn; highly contagious superficial infection caused by S. aureus Staphylococcal toxemias; scalded skin syndrome / toxic shock syndrome |
|
|
What bacteria are active in acne?
|
Propionibacterium acnes can metabolize sebum in hair follicles
|
|
|
What is treatment for acne?
|
Treatment: Tretinoin, benzoyl peroxide, erythromycin, Accutane
|
|
|
What kinds of strep skin infections are there?
|
Gram positive cocci (catalase negative)
Group A Strep (Streptococcus pyogenes) |
|
|
What are specific examples of Strep involved in skin disorders?
|
Erysipelas (reddish patches)
Impetigo (isolated pustules) Invasive Gp. A Strep causes severe and rapid tissue destruction Scalded Skin Syndrome → exfoliative toxin Flesh-eating bacteria → necrotizing fasciitis |
|
|
What bacteria are involved in burn infections?
|
Pseudomonas aeruginosa produces an endotoxin and several exotoxins
Otitis externa Infections in burn wounds |
|
|
What causes warts?
|
Papillomavirus and spread by direct contact
|
|
|
What causes Chicken-pox?
|
Varicella-zoster virus
-Spread via respiratory route Localized in skin cells, causing a vesicular rash Complications → encephalitis & Reye’s Syndrome Vaccine is available for chickenpox |
|
|
Shingles
|
a recurrence of VZ infections
Vesicular rash along affected cutaneous sensory nerves Seen primarily in older adults |
|
|
Herpes Simplex
|
Cold sores, occasionally encephalitis
Virus remains latent in nerve cells & can be reactivated under various stimuli (sunlight, stress) HSV-1 transmitted by oral and respiratory secretions Virus can infect the brain; Herpes encephalitis Acyclovir is effective in Herpes infections |
|
|
Smallpox
|
Caused by Variola virus (variola major & variola minor)
Transmitted by respiratory route and causes a skin rash Infects only humans Vaccination has resulted in eradication of the virus Can potentially be used as a biological weapon |
|
|
Measles (Rubeola)
|
Caused by the measles virus and transmitted via respiratory route
Macular lesions on skin / Koplik’s spots on oral mucosa Complications → ear infections, pneumonia, encephalitis, secondary bacterial infections Good vaccine provides long-term immunity |
|
|
Rubella
|
Transmitted via respiratory route
Red rash, low-grade fever, or asymptomatic Congenital rubella syndrome; can affect developing fetus during first trimester of pregnancy Damage includes stillbirth, deafness, eye catatacts, heart defects, and mental retardation Vaccine is available Fifth Disease → Human parvovirus B19 HHV-6 → roseola |
|
|
Tinea = Ringworm
|
Types of Infection
Tinea capitis (ringworm of the scalp) Tinea cruris Tinea pedis (athlete’s foot) Organisms involved Trichophyton spp. Microsporom spp. Epidermophyton floccosum |
|
|
Describe Candida albicans
|
an opportunistic pathogenic yeast
Oral Thrush Vaginitis (vaginal yeast infections in women) |
|
|
Subcutaneous Mycoses
|
Sporotrichosis caused by Sporothrix schenckii
Acquired from rose bush thorns |
|
|
Scabies
|
Intense local itching
Mites burrow under skin & lay eggs Sarcoptes scabiei |
|
|
Pediculosis
|
infestation by P. humanus capitis (head louse)
Itching due to feeding of the lice Egg packets are referred to as “nits” |
|
|
Usual Flora distribution for upper and lower respiratory tract
|
Upper respiratory system has many usual flora
Lower respiratory system has very little usual flora |
|
|
Diseases of Upper Respiratory Tract
|
Streptococcal pharyngitis → Gp. A Strep and strep throat
Scarlet fever → also caused by certain strains of Streptococcus pyogenes Diphtheria → Corynebacterium diphtheriae Otitis Media → H. influenzae, Gp. A Strep St. pneumoniae, M. catarrhalis, S. aureus |
|
|
Diseases of lower respiratory tract
|
Whooping Cough
Caused by Bordetella pertussis Disease consists of catarrhal stage, paroxysmal stage, convalescent stage Childhood immunization has decreased the incidence of disease |
|
|
Tuberculosis
|
Caused by Mycobacterium tuberculosis, an intracellular parasite
Tubercles in the lung with characteristic x- ray picture upon caseation When caseous lesions rupture, TB can spread throughout the body Tuberculin skin test indicates exposure BCG vaccine used in some countries M. avium-intracellulare in AIDS patients |
|
|
Common cold
|
Mostly upper respiratory tract.
can be caused by over 200 different viruses 50% caused by rhinoviruses sneezing, nasal secretions, congestion complications: sinus infections, lower respiratory tract infections, laryngitis, ear infections most often spread by direct contact |
|
|
Ty[es of pneumonias
|
Pneumococcal pneumonia → caused by Streptococcus pneumoniae
Haemophilus pneumonia → Haemophilus influenzae Mycoplasmal pneumonia → Mycoplasma pneumoniae and walking pneumonia Legionellosis → Legionella pneumophila (Legionnaires disease and Pontiac fever) |
|
|
iral pneumonias
|
often seen as a complication of influenza
Respiratory Syncytial Virus most common cause of pneumonia in infants can be treated with Ribavirin |
|
|
INfluenza
|
Influenza →caused by influenza virus
Hemagglutinin (H) and Neuraminidase (N) determine antigenic differences in strains Antigenic shift → represent major changes in H and N properties Antigenic drift → minor changes in H and N Deaths during outbreaks usually due to secondary bacterial infections Influenza virus A can be treated with amantadine and rimantadine Tamiflu (oseltamivir phosphate) → a neuraminidase inhibitor that is useful in the treatment and prophylaxis of influenza |
|
|
Histoplasmosis
|
caused by Histoplasma capsulatum
Found in the Midwestern states along the great river valleys (fungal disease) |
|
|
Blastomycosis
|
(Fungal disease)
caused by Blastomyces dermatitidis Found in the same areas as Histoplasma capsulatum |
|
|
Coccidioidomycosis
|
systemic disease caused by Coccidioides immitis
A fungus growing in the soil (arthroconidia) Valley fever Spherules in the lung Endemic in Southern California |
|
|
Pneumocystis carinii pneumonia
|
caused by pneumocystis carinii
Seen almost exclusively in AIDS patients |
|
|
bacteria pneumonias
|
Psittacosis → Chlamydia psittaci
Chlamydial pneumonia → Chlamydia peumoniae Q-fever → Coxiella burnetii Other bacterial agents of pneumonia: Staphylococcus aureus, Streptococcus pyogenes, Moraxella catarrhalis, Klebsiella pneumoniae, Pseudomonas aeruginosa and others |
