Viral, Bacterial, Fungal and Parasitic Disorders of the Skin Flashcards
What are some characteristics of defensins?
Defensins are small, cationic, cysteine-rich peptides that differ in their disulfide-bond paring and tissue distribution
What cells are alpha-defensins found?
They are found primarily in neutrophils in the small intestines, but small amounts in keratinocytes.
What cells are beta-defensins found?
Keratinocytes
Beta-defensins demonstrate anti-microbial activity against what microorganisms?
G(+), G(-), viruses and yeast
Cathelicidin HCAP-18 are small, cationic peptides that have broad spectrum antimicrobial activity by using what enzymatic activity?
cysteine protease inhibitory activity
What protects the skin against fecally-derived gram-negative bacteria?
Psoriasin and RNase 7
At what pH do pathogenic bacteria grow? Normal flora?
Pathogenic- neutral pH
Normal flora- acidic
What type of genome does human papillomavirus have?
Non-enveloped double-stranded DNA virus
How can you diagnose HPV?
Look at the clinical presentation, do a biopsy, or DNA/RNA in-situ hybridization
What type of genome does Herpes have?
Double-stranded DNA
WHat preparation can you utilize to visualize herpes?
Tzanck smear- prepared by scraping of a vesicle base and using stains that demonstrate nuclear morphology (Wright)
What causes non-bollous impetigo and affects mostly children and makes up the majority of impetigo cases?
Streptococcal
What causes bollous impetigo and what areas of the body does it affect?
Staphylococcus. All parts of the body
What is erysipelas?
Variant of cellulitis cause by beta-hemolytic strep. Affects the face
What can cause cellulitis?
Beta-hemolytic strep, staph aureus, haemophilus influenzae
