Dermatology Flashcards
Langerhans cells
found where, function, derived from, granule shape and name
dendritic cells found in skin that act as professional antigen presenting cells, derived from the myeloid cell line and possess racquet shapped intracytoplasmic granules known as Birbeck granules.
Langhans cell
nuclei shape and number, derived from, function
multinucleated giant cell with horseshoe shaped arrangement of multiple nuclei derived from monocytic cell line, play role in granulomatous inflammation.
Merkel cells-cell type, location, function, pathology example
neuroendocrine cells of the basal layer of epidermis, perception of touch, associated with Merkel cell carcinoma (a type of skin cancer)
Melanocytes germ cell layer, location, function, number in dark vs white skin ppl
neural crest cells the migrate to basal layer during embryogenesis, pigment producing cells. dark skin doesn’t increase number but means increased production of melanin.
monocytes- stimulated to become, function (liver, bone, CNS, kidney and lung)
stimulated to become macrophages, serve specialized function in different organs (liver-kupffer cells, bone-osteoclasts, CNS-microglia, kidney-mesagial cells, and lung-alveolar macrophages)
Chediak-Higashi syndrome- def and presenting symptoms
autosomal recessive disorder of neutrophil phagosome lysosome fusion
-neurological abnormalities (nystagmus), partial albinism (abnormal meanin storgae in melanocytes), and immunodeficiency due to defective neutrophil function.
Phenylketonuria-def, impaired conversion of what to what? presenting features
deficiency phenylalanine hydroxlyase
- impaired conversion of tyrosine to phenylalaine
- CNS abnormalities (mental retardation, developmental delay), albinsm, and mousy odor
Wiskott-Aldrish Syndrome-genetic inheretance, triad
X-linked
-immunodeficiency (both T and B lymphocyte disorder), eczema, and thrombocytopenia
which nucleotide enzyme is needed to make melanin in melanocytes? can result in?
tryrosinase
albinism
splice site mutations result in proteins that are (size, function, immune response)
- larger size (all introns not spliced out)
- altered function (improper folding)
- preserved immune reactivity (all exons are present)
skin lesion:
- hyperpigmented and not raised
- pigmented, raised, after trauma
- pigmented,raised, alters with menstrual cycle
- pigmented raised and applying pressure causes retraction “button hole sign”
- pigmented and raised
- no pigment and beneath skin
- ephelides (freckles)
- keloid
- accessory nipple
- cutaneous neurofibroma
- pigmented nevus
- lipoma
timing and symptoms of
- graft-T cell sensitization against host MHC antigens
- host T-cell sensitization against MHC antigens
- host T-cell sensitization against ABO antigens
- 1 week, graft versus host disease, skin (jaundice, desquamation), liver (increased AST,ALT alkaline phosphate and bilirubin) and GI (diarrhea, intestinal bleeding, abdomnial cramping, and ileus)
- can be acute=vasculitis of great vessels or chronic=fibrosis of graft stroma and blood vessels
- acute (minutes), spasm and occlusion of graft vessels, ischemia and necrosis
skin presentations (age, lesion characteristics, and associations) of gluten enteropathy vs atopic dermatitis (aka eczema)
- childhood disease. pruritus and erythematous, weeping/crusted papules and plaques in lichenifications in flexural distribution (neck, wrists, antecubital and poplitea fossae). associated with other atopic disease like allergic rhinitis and asthma
- adult disease. associated with dermatitis herpetiformis, clusters of pruritic vesicles and plaques on buttocks and extensor surfaces of extemities
skins disease with erythematous, well- demarcated papules and plaques with a silvery scale.
psoriasis
mech of disinfectant. is it sporicidal?
- alcohols (isopropanol, ethanol)
- chlorhexidine
- hydrogen peroxide
- iodine
- disruption of cell membranes, denaturation of proteins; no
- disruption of cell membranes coagulation of cytoplasm; no
- produces destructive free radicals that oxidize cellular components; yea
- halogenation of proteins and nucleic acids; yes
which antibiotics are effective against pseudomonas?
- anti-pseudomonal
- cephalosporins
- aminoglycosides
- fluoroquinolones
- monobactams
- carbapenems
- ticarcillin and piperacillin
- ceftazidime (3rd gen) or cefepime (4th gen)
- amikacin, gentamicin, tobromycin
- ciprofloxacin and levofloxacin
- aztreonam
- imipenem and meropenem
Nikolsky’s sign, associated toxin and bacteria and pt pop
skin slipping off with gentle pressure
- S. aureus
- exfoilatin
- children and infants
Hartnup disease vs Fanconi syndrome
- loss of neutral amino acids
- generalized aminoaciduria
Hartnup disease presentation and treatment
- most of clinical presentation is due to loss of tryptophane a precursor for niacin, serotonin, and melatonin
- waxing and waning symptoms of photosensitivity, pellagra like skin rashes, ataxia.
- give niacin (nicotinamide+vit amine V3) or nicotinamide and high protein diet
which vitamin can be of benefit to measles infection?
vitamin A
what do nucleoside analogues require that nucleosides don’t in order to be effective? give examples of both types?
- sides require a viral cellular kinase
- tides already have their phosphate group attached and do not require viral kinase
- Tides-cidofovir, tenofovir
- Sides-acyclovir, valacyclovir, famiciclovir, ganciclovir
- mech of drugs used to treat psoriasis
- Calcipotriene
- Cyclosporine
- Etanercept
- MTX
- Ustekinumab
- topical vit D analog (aka calcipitriol) that bind vit D recetor and inhibits keratinocyte proliferation and stimulate keratinocyte differentiation
- inhibits NFAT (nuclear factor of activated T cells) from entering nucleus and modulating activity (imparing production of IL-2 which activates T cells)
- recombinate form of TNF that binds to TNF-alpha
- foalte antimetabolite that targets rapidly growing cells in skin
- human monoclonal antibodties that targets IL-12k IL-23 to inhibit t cell differentiation and actication
mutation in melanoma
- BRAF is a protein kinase involved in activation of signaling pathways for melanocyte proliferation
- it is mutated V600E in 50% if pt
gland found where/ function
- apocrine
- holocrine
- eccrine aka merocine
- paracrine
- dermis and subcutaneous fat of breast areloae, axillae and genital regions. sweat into hair follicles usually odorless but become malodorus secondary to bac decomposition
- associated with sebaceous glands, discharge of entire secretory cell
- in skin expect for lips and glans penis. Na and Cl- rich sweat direct onto skin
- similar to endocrine glands. reach target cells by diffusion instead of circulation
mc cause of hair loss? inheritance?
androgenic alopecia
- in both men and females
- polygenic inheritance with variable penetrance
name some common conditions influenced by multiple genes (CNS-3, Cardio-2, Endo-1, Derm-1, Onc-1)
androgenic alopecia epilepsy ischemic heart disease schizophrenia glaucoma HTN malignancy type II DM
axillary node dissection is a risk factor for? can lead to what sarcoma?
- chronic lympadema
- angiosarcoma (Stewart-Treves Syndrome)
- multiple firm violaceous (purple) nodules
structure of tRNA
- acceptor stem
- 3’ end contains?
- D arm
- anticodon arm
- T arm
- 5’ end contains?
- paris of 5’ and 3’ terminal nucleotides. helps to mediate correct tRNA recognictions and amitoacyl tRNA synthetase
- CCA is added as a postranslation modification
- contains numerous dihydrouracil residues
- sequences complemetary to mRNA codon and is read in 3’ to 5’ direction
- thymidine, pseudouridine, and cytidine residues
- terminal phosphate
which is only RNA molecule with thymidine?
tRNA
marjolin’s ulcer
example of malignant transformation.
-SCC that presents in area of previously tramatized, chronically inflammed or scarred skin.
more than 10yrs
what is excessive granulation formation. pt pop, histo
- keloids
- african americans
- haphazard arrangement of thick, pink collagen bindles
complication of VZV infection
- in thoracic dermatone
- trigeminal nerve?
- post-herpetic neuralgia
- visual impairment
