Diseases Week 1 Flashcards
Spitz Nevi
Bright red dome-shaped nodule. Unpredicatable behavior that can become melanoma –> Excise all.
Necrotizing Fascitis
trauma allows for deep seated infection–> release of exotoxin B (protease) –> rapid necrosis along fascial planes w/ no damage to muscles. Treat aggressively and fast. IV AB’s and debridement/amputation.
Aquired localized increase in sebaceous glands. Larger than normal glands. Yellow papules
Sebaceous hyperplasia
Common (acquired) and Congenital Nevi
Most common pigmented lesion. Higher risk for melanoma.
Nephrogenic Systemic Fibrosis (NFS)
Rare condition caused by gadolinium based contrast agents. Causes multisystem fibrosis esp in skin and subcutaneous tissues. Risk factors include: chronic renal insufficiency, chronic hemodialysis, and multiples exposures to contrast. Screen for renal dysfunciton.
Skin tag/ Fibroepithelial polyp/ Acrochordon
Very common cutaneous lesion, not neoplastic. Soft flesh colored bag-like tumor with stalk.
Bullous pemphigloid
Autoimmune blistering disorder of dermis-endodermis (hemidesmosome) juction. Blister in lamina lucida region.
Most common human malignancy –> pearly papule with telangiectasia (defined blood vessels in papule) Slow growing. Rarely metastasize Risk factors: sun exposure, light pigment, XP
Basal Cell Carcinoma
Impetigo
Lesions look like peeling skin, crusty and flaky scabs, or honey-colored crusts. Usually around mouth face and extremeitis. Same for SA and SP. Treat both bacteria.
Nevus of Ota/Ito
Ota: Peri-Ocular, intraocular dermal melanocytic nevus Ito: Mongolian spot, same type of lesion, different site.
Hemangioma
Well formed benign vascular spaces in dermis. Clinically must seperate from malignant vascular neoplasms
Benign fibrous histocytoma or Dermatofibroma
Very common dermal proliferation of histiocytes and fibroblasts. Tan brown firm papules. Use pinch test (squeeze edges of lesion and dimple will appear in middle of lesion most of the time)
Very aggressive epithelial neoplasm mostly caused by polyomavirus. Presumed to differentiate as Merkel cells (touch cells). Microscopicall mimics small cell lung carcinoma and lymphoma.
Merkel cell carcinoma
Hyper pigmentation of basal epidermis due to excess melanin production
Solar Lentigo
Common epithelial neoplasm. Brown and velvety papules/plaques. Related with age and normally benign. Due to increased melanin not melanocytes. Leser-Trelat Sign- paraneoplastic, rapid growth of numerous seborrheic keratoses.
Sebhorrheic Keratosis
Benign lobular circumscribed neoplasm of sebocytes and peripheral basaloid epithelial cells
Sebaceous Adenoma
Very common dermal proliferation of histiocytes and fibroblasts. Tan brown firm papules. Use pinch test (squeeze edges of lesion and dimple will appear in middle of lesion most of the time)
Benign fibrous histocytoma or Dermatofibroma
Psudomonas Aeruginosa
Burn wound infection (cellulitis) and folliculitus (hot tub foliculitis) Infection arises by breach of host defense barriers.
skin infection (cellulitis) –> systemic release of pyrogenic exotoxins A (superantigen) or TSS1 –> polyclonal T cell activation –> acute fever, shock, multiorgan failure
Toxic Shock Syndrome
Staphylococcal Scalded Skin Syndrome (SSSS)
dermolytic condition caused by SA. Affects mostly newborns and babies. Like impetigo it is an exotoxin-mediated disease (systemic form) ET-A and ET-B. Breaks connection of dermis and epidermis.
Malignant neoplasm. Most are periocular (inner/outer lid) Extraocular forms are more likely in Muir Torre Syndrome Metastasis common, death in 20%
Sebaceous Carcinoma
Sebaceous Adenoma
Benign lobular circumscribed neoplasm of sebocytes and peripheral basaloid epithelial cells
Dysplastic Nevi (DPN)
Irregular shaped nevi that can be familial or sporadic. Multiple DPN = increased risk of melanoma. Excise moderate and severe atypia (mild can go either way).
Differentiate toward hair follicle, eccrine, sebacious, eccrine, and apocrine glands. Benign and malignant types. Too many to learn. Can be a clue to internal pathology (Cowden’s and Muir Torre)
Adenexal Proliferations/Neoplasms
Papules and nodules of skin in infants/children. Dendritic cells arise in bone marrow and travel to skin. Skin has dense dermal infiltrate of LCs.
Langerhans cell histiocytosis
Muir-Torre Syndrome
Germline mutations in DNA mismatch repair proteins: MLH1, MLH2, MSH6, PMS2. Skin: sebaceous adenoma and carcinoma, keratoacanthomas. Internal carcinomas: Colon/Rectal, endometrial, ovarian Rerpresents subset of HNPCC (hereditary non-polyposis colorectal carcinoma syndrome) Young Aduld w/ sebaceous adenoma or carcinoma –> test for MTS
Basal Cell Carcinoma
Most common human malignancy –> pearly papule with telangiectasia (defined blood vessels in papule) Slow growing. Rarely metastasize Risk factors: sun exposure, light pigment, XP
Most likely to occur in line with pedicles. Most likely causes problems with inferior spinal cord(s)
Herniated disc
Lentigo Simplex
Localized hyperplasia of melanocytes that is not sun related. Small brown macules with uniform coloration.
Toxic Shock Syndrome
skin infection (cellulitis) –> systemic release of pyrogenic exotoxins A (superantigen) or TSS1 –> polyclonal T cell activation –> acute fever, shock, multiorgan failure
Most common pigmented lesion. Higher risk for melanoma.
Common (acquired) and Congenital Nevi
Sebhorrheic Keratosis
Common epithelial neoplasm. Brown and velvety papules/plaques. Related with age and normally benign. Due to increased melanin not melanocytes. Leser-Trelat Sign- paraneoplastic, rapid growth of numerous seborrheic keratoses.
Most common type of cutaneous T cell lymphoma. Neoplastic cell is CD4+
Mycosis Fungoides
Common neoplasm on sun exposed skin in older people. Largest risk factor is sun exposure. Also XP In situ: contained above basement membrane Invasive: invades basement membrane and dermis Less than 5% will metastasize.
Squamous Cell Carcinoma
Rocky Mountain Spotted Fever
Causative agent- Rickettsia rickettsii (obligate intracellular and palm and sole rash big indicators) Clinical Presentation: Rash, fever, headache Pathology: Dermacentor wood or dog tick –>inflamation of endothelial cells of small blood vessels –> macopopular rash on palms and soles spreading to the trunk –> headache and CNS changes, renal damage –> death if untreated (mortality = 30%) Treatment - Doxycycline
Breslow Depth test
Depth of invasion of melanoma is the best predictor for the probability to metastasize. >1mm = do sentinel node biopsy. Other important indicators are ulceration and mitotic rate.
Well formed benign vascular spaces in dermis. Clinically must seperate from malignant vascular neoplasms
Hemangioma
Dermatofibrosarcoma Protuberans (DFSP)
Well differentiated fibrosarcoma of skin. Rarely metastasize/locally aggressive. Protuberant nodule within a firm plaque.
Germline mutations in DNA mismatch repair proteins: MLH1, MLH2, MSH6, PMS2. Skin: sebaceous adenoma and carcinoma, keratoacanthomas. Internal carcinomas: Colon/Rectal, endometrial, ovarian Rerpresents subset of HNPCC (hereditary non-polyposis colorectal carcinoma syndrome) Young Aduld w/ sebaceous adenoma or carcinoma –> test for MTS
Muir-Torre Syndrome
Solar Lentigo
Hyper pigmentation of basal epidermis due to excess melanin production
trauma allows for deep seated infection–> release of exotoxin B (protease) –> rapid necrosis along fascial planes w/ no damage to muscles. Treat aggressively and fast. IV AB’s and debridement/amputation.
Necrotizing Fascitis
Melasma
Butterfly mask like facial hyperpigmentation. Can be brought on by pregnancy or OCPs (reversible)