Other Diseases Flashcards
Toxoplasmosis Transmission
Infection occurs by ingestion of oocysts (hand-to-mouth), other modes of transmission are undercooked pork or lamb
Causitive Organism of Syphilis
Treponema pallidum (spirochete, gram negative)
Syphilis Transmission
- Direct contact
- Perinatally
Primary Syphilis Symptoms
- After 10-90 day incubation
- Chancre: painless lesion
- Enlarged Lymph Nodes
- Spirochetes visible through dark field analysis of skin lesions
Secondary Syphilis Symptoms
- 3-6 weeks after Primary Syphilis symptoms
- Skin rash, fever, malaise, pharyngitis, weight loss, and lymphadenopathy
- Skin/mucous membrane lesions that still contain spirochetes
- Produces positive Serological tests
Late Latent Syphilis Symptoms
No signs or symptoms, but Treponemal and Non-treponemal tests are positive
Tertiary Syphilis Symptoms
- Gummas: lesions throughout body
- Aortic problems
- Neurosyphilis: CNS seizures, dementia
Non-treponemal Tests
Detect antibody to cardiolipin, VDRL and RPR
Treponemal Tests
- FTA-ABS (Fluorescent Treponemal Antibody Absorption Test)
- EIA
- DNA Probe
False Negative and False Positive Results in VDRL and RPR
Negative:
- Early Primary Stage
- Prozone phenomenon in Secondary stage
- Late Stage (Postzone)
- Immunosuppressed Pt
Positive:
- Due to similar Ag that can be found in SLE, Autoimmune diseases, pregnancy, and some chronic infections (Hepatitis)
CRP
A type of non-specific Ab-like protein for defense against infection
Found in high levels ininfection, surgery, and other trauma (inflammation)
Cause of Atypical Pneumonia
Mycoplasma pneumoniae
Cold Agglutinin Cause (Outside infection)
Infection with M. pneumoniae that creates cross-reactive Ab that start to bind I/i Ag on RBCs in vivo
Causitive Agent of Strep Throat
Streptococcus pyogenes
Consequences of untreated Strep Throat
Acute Rheumatic Fever
Post-streptococcal glomerulonephritis
S. pyogenes Skin Infection
Necrotizing faciitis
Exotoxins(Antigens) produced by S. pyogenes
- Streptolysin O
- DNase B
- Hyaluronidase
- NADase
- Streptokinase
hCG
Used in pregnancy testing, in either urine or serum samples
Latex agglutination Pregnancy Test
Anti-hCG is mixed with Pt urine on slide, then hCG coated latex particles are added.
If hCG was present in the urine, it will already have bound to the anti-hCG and there will be nothing left to bind with the latex particles; meaning no agglutination is a positive test
ELISA for pregnancy testing
Uses hCG specific Ab bound to a solid media or linked to a specific enzyme.
- In solid media, the Ag-Ab form complexes and precipitate
- In enzyme linked, the Ag-anti-hCG-enzyme form a sandwich, and unbound enzyme is washed away. Substrate is added that causes a color change that can be read.
Disorders Causing False Positive Pregnancy Tests
- Choriocarcinoma
- Pituitary disorders
- Ovarian cysts
- Bladder/Ovarian Cancer
Choriocarcinoma
A malignant, trophoblastic cancer, usually of the placenta whose cells produce hCG
Pituitary Disorders In Pregnancy Testing
- Tumors can stimulate the pituitary gland to produce hCG
- Menopause can also produce hCG
- Pituitary can also create hCG even when no disorder or tumor is present
Ovarian Cysts in Pregnancy Testing
Corpus luteum left in ovary after egg is released can produce hCG
