Serology Flashcards
Serology
The diagnostic identification of antibodies in the serum
HIV anitbody Testing
All US tests detect HIV-1 and some HIV-2
HIV 1 - most common in US
HIV 2- Africa
Sensitive - ELISA
Specific - Western Blot
Screening test - ELISA
Western Blot Testing
immunoassay test method that detects specific proteins in blood or tissue.
combines an electrophoresis step with a step that transfers (blots) the separated proteins onto a membrane.
often used as a f/u test to confirm the presence of an antibody and to help diagnose a condition such as HIV or Lyme Disease testing.
Hepatitis A, B, C
Inflammation of the liver, can lead to liver cancer and transplant need.
Active Test - Antigen - HsAg
Prior Exposure - Antibody - HsAb
HEP A (HAV)
Aquired through food or water
There is a Hepatitis A Vaccine
Symptoms may include jaundice and severe stomach pains and diarrhea
Self-limiting
HEP A Test Results
HAV-Ab IgM- exposed. Antibodies will begin 2-3 weeks after first being infected and persist about 2-6 months
HAV-Ab IgG-produced 1-2 weeks after IgM and persist for life
HAV-Ab total-may help determine if you have been infected and have some immunity to the disease
HEP B
not as common, generally self-limiting
Can create a “Chronic-active” state in some people who recover from symptoms but are still contagious and never fully recover.
contracted through blood, blood products, and sex
*STI-like
HEP B Testing
HBV-Ag
HBV-Ab
HBV-D
Hepatitis B tests may be used for a variety of reasons.
detect antibodies produced in response to HBV infection
detect antigens produced by the virus
detect viral DNA.
HEP C (HVC)
Hepatitis C infection is caused by the hepatitis C virus (HCV).
Hepatitis C is transmitted by blood and sexual activity
**very infectious
Exposure may occur:
After a needle stick or sharps injury If blood from someone who has hepatitis Ccontacts a cut on your skin or contacts your eyes or mouth
People at high risk for HEP C
Inject street drugs or share a needle with someone who has hepatitis C
Have been on long-term kidney dialysis
Have regular contact with blood at work (such as a health care worker)
Have unprotected sexual contact with a person who has hepatitis C
Were born to a mother who had hepatitis C
Received a tattoo or acupuncture with needles that were not disinfected properly after being used on another person (risk is very low with practitioners who have a tattoo license or permit or an acupuncture license)
Received an organ transplantfrom a donor who has hepatitis C
Share personal items such as toothbrushes and razors with someone who has hepatitis C (less common)
Received a blood transfusion (rare in the U.S.)
Clearance rates for HEP A, B, C
90% clear Hep B, 95% clear Hep A, 95% of people DO NOT clear Hep C
HEP D
Hepatitis D virus (HDV) is found only in people who carry the hepatitis B virus.
**If someone is taking a long time to clear HEP B - suspicious of D.
HDV may make a recent (acute) hepatitis B infection or an existing long-term (chronic) hepatitis B liver disease worse.
It can even cause symptoms in people who carry Hepatitis B virus but who never had symptoms
Hepatitis D infects about 15 million people worldwide.
It occurs ina small numberof people who carry hepatitis B.
HEP D Risk Factors
Abusing intravenous (IV) or injection drugs
Being infected while pregnant (the mother can pass the virus to the baby)
Carrying the hepatitis B virus
Men having sexual intercourse with other men
Receiving many blood transfusions
Cystic Fibrosis
Autosomal recessive genetic disorder
Delayed growth, Clay or pale colored stools, coughing, sinus pain, recurrent respiratory infections
In CF, thick mucus can obstruct pancreatic ducts and prevent trypsinogen from reaching the intestine. Blood IRT levels will be elevated in newborns with CF, but positive results must be followed by confirmatory testing.
CF Testing
ACMG recommends a panel of 23 of the most common CFTR mutations be used to screen general or targeted populations for cystic fibrosis and CF carrier status.
Trypsin/chymotrypsin: stool test, screening for pancreatic insufficiency
Immunoreactive Trypsinogen (IRT): This test is a newborn screening tool for trypsinogen, which is produced in the pancreas and transported to the intestine, where it is activated to form the enzyme trypsin.
CF Sweat Chloride Test
the sweat of a person with CF may be up to five times saltier than normal.
Positive sweat chloride test results should be confirmed and followed with CF gene mutation testing whenever possible
ASO Titer
<200 IU/mL
Streptococcal Infections (pharyngitis, scarlet fever, rheumatic fever, poststreptococcal glomerulonephritis)
RA
Other collagen diseases
Monospot
normal= negative
POSITIVE-
Mononucleosis
Viral Hepatitis
RA
Infectious mononucleosis, commonly called mono, refers to an infection caused by the Epstein-Barr virus (EBV). This test detects proteins in the blood called heterophile antibodies that are produced by the immune system in response to an EBV infection.
No sports for 6-8weeks - splenic enlargement
Heterophile Antibody Testing
specifically refers to a rapid test for antibodies produced against the Epstein-Barr virus (EBV), the causative agent of infectious mononucleosis
Epstein Barr/ Herpesvirus 4
Someone w/neg. monospot
Also associated with cancers: Hodgkin’s lymphoma, Burkitt’s lymphoma, nasopharyngeal carcinoma and lymphomas associated with HIV
CMV
IgM <1:8; IgG<1:16
generally passed from infected people to others through direct contact with body fluids, such as urine, saliva, vaginal secretions, and semen.
Common exposure for babies is from kissing babies.
Self-limiting, can cause an eye infection which can cause blindness.
Syphilis
An STD caused by Treponema pallidum
VDRL: Veneral Disease Research Laboratory Test, invented before WWI
Syphilis Testing
RPR: Rapid Plasma Reagin - Screening Test ( sensitive)
And FTA-Abs: Fluorescent treponemal antibody-absorption ( confirmation test - specific)
MHA-TP: Microhemagglutination assay-confirms a syphilis infection after another method tests positive for the syphilis bacteria
Syphilis Stages
Primary: single sore marks the first (primary) stage of syphilis symptoms, but there may be multiple sores.
Secondary Stage: Papulosquamous lesions
Latent Tertiary Stage: dementia, blindness, damage to brain, nerves, eyes, heart, etc.
Anti-nuclear antibodies
(ANA)
Useful screening test in patients with symptoms suggesting collagen-vascular disease esp. if titer is >1:160
Positive: SLE, lupus like syndromes, scleroderma, RA, Polymyositis, raynaud’s
c-ANCA
Wegener’s granulomatous-Wegener’s granulomatosis is a rare disorder in which blood vessels become inflamed, making it hard for blood to flow.
Wegener’s granulomatosis mainly affects blood vessels in the nose, sinuses, ears, lungs, and kidneys, although other areas may be involved.
p-ANCA
polyarteritis nodosa Polyarteritis nodosa is a disease that affects arteries, the blood vessels that carryoxygen-rich blood to organs and tissues. The cause is unknown, but it occurs when certain immune cells attack the affected arteries.
Rheumatoid Factor
A test for RF may be ordered if a patient has signs of RA.
Symptoms may include pain, warmth, swelling, and morning stiffness in the joints, nodules under the skin, and, if the disease has progressed, evidence on X-rays of swollen joint capsules and loss of cartilage and bone.
Rheumatoid Factor
A test for RF may be ordered if a patient has signs of RA.
<15 IU
Increased-
Collagen-vascular disease
(RA, SLE, scleroderma, polyarteritis nodosa)
Infections (TB, syphilis, viral hepatitis)
Symptoms of RA
Symptoms may include pain, warmth, swelling, and morning stiffness in the joints, nodules under the skin, and, if the disease has progressed, evidence on X-rays of swollen joint capsules and loss of cartilage and bone.
**usually effects joints symmetrically. Most frequently the writs, hands, elbows, shoulders, knees and ankles.
Legionella
<1:32 titers
Cases of Legionnaires’ disease have been linked to many types of equipment that contain water, but plumbing systems and air conditioning systems are most often blamed.
most cases have been legionella cases are traced to large buildings.
Larger piping networks are generally more conducive to legionellae growth. Also, the air conditioning systems for large buildings often include cooling towers, which contain a pool of warm water in which legionellae can flourish.
Legionares disease
causes pneumonia
H-pylori
IgG <0.17=negative
May test by Serology, C-breath test, gastric mucosal biopsy, and the Campylobacter-like organism test (rapid urease test) from biopsy sample as well.
H. Pylori Tx
- Triple
Clarithromycin+amoxicillan+PPI - Quadruple
Bismouth+ metronidazole+ tetracycline+ PPI - Sequential-
PPI+amoxicillin 5 days, followed by PPI + clarithromycin + metronidazole for 5 days - Combo products-
Helldac
Pylera
Prevpac
Rocky Mountain Spotted Fever
Causative agent-Rickettsia Rickettsii
Mostly in spring/summer
Vector-
American Dog Tick found in high grass and
low shrubs, and fields
Symptoms of Rocky Mountain Spotted Fever
Abdominal pain, diarrhea, muscular and joint pain
Severeve headsche, chills, Fever to 103-104, Restlessness
Petechial rash on wrists/ankles, palms/soles and forearms.
Lyme Disease
Causative Agent-
Borrelia Burgdorferi
Mostly spring, but year round
Deer tick vector.
May use Western Blot test
Can look for antibodies and antigen via ELISA.
**bullseye rash
PSA
<4ng/dL
Most useful as a measure of response to therapy of prostate cancer; approved for screening of prostate cancer.
Levels >10ng/dL are frequently associated with carcinoma
Indications of increased PSA
Prostate Cancer
Acute Prostatitis
Some cases of BPH
Prostate surgery
Vigorous prostate massage
Indications of decreased PSA
Radical prostatectomy
Response to therapy of prostatic carcinoma (radiation or hormonal)
CEA
Used to monitor the treatment of people diagnosed with colon cancer
Good marker to follow for recurrence of carcinomas of the GI tract
Indications of Increased CEA
Carcinoma of the colon
Pancreatic cancer
Lung cancer
Stomach cancer
UC/Crohn’s disease
CA19-9
<37kU/L
Tumor marker helpful to differentiate between cancer of the pancreas and other conditions, such as pancreatitis
Increased in GI cancers-pancreas, stomach, liver, colorectal, hepatobiliary, some cases of lung and prostate, pancreatitis.
Mostly pancreatic/hepatocellular
Not specific or sensitive
Order with other tests
CA-125
<35kU/L
Not a useful screening tool for ovarian cancer when used alone-best used in conjunction with ultrasound and physical examination
Indications of Increased CA-125
Ovarian Cancer
Endometrial Cancer
Colon Cancer
Endometriosis
IBD
PID
AFP
alpha feto protein -
liver function
Indications of increased and decreased AFP
Increased-
Hepatoma
Hepatocellular Carcinoma
Testicular Tumor
Neural Tube Defects
Decreased-
Trisomy 21 (Down Syndrome) in maternal serum
HCG
Human Corinotic Gonadotrpoic
<0.3mIU/mL
Hydatidiform mole is a rare mass or growth that forms inside the womb (uterus) at the beginning of a pregnancy.
It is a typegestational trophoblastic disease (GTD). A cancerous form of GTD is choriocarcinoma. Usually >100,000 mIU/mL
HCG is elevated in normal pregnancy as well.
Indications for Increased HCG
Pregnancy
Some germ cell tumors
Hydatidiform mole
Molar pregnancy
choriocarcinoma
A molar pregnancy
also known as hydatidiform mole — is a noncancerous (benign) tumor that develops in the uterus.
A molar pregnancy occurs when the placenta develops into an abnormal mass of cysts rather than becoming a viable pregnancy.
