Concepts in Pathophysiological Diagnosis – Exam #2 Study Guide (Q&A; Inline)

A comprehensive set of flashcards based on concepts from pathophysiological diagnosis covering immunologic tests, cardiovascular system tests, pulmonary system tests, endocrine system tests, and digestive system tests.

True or False: Type AB blood is a universal donor because it does not have any A or B antibodies in the plasma.

False. AB blood is a universal recipient because their plasma contains no antibodies against A or B.

What does minor matching test mean?

It checks for antibodies in the donor’s plasma that could attack the recipient’s red blood cells (less important).

What is direct antiglobulin test (direct Coombs test) used for?

Used to test for autoimmune hemolytic anemia.

Describe the steps in indirect Coombs test.

Small amount of recipient serum is added to donor RBCs; then Coombs reagent is added; if antibodies are present, visible agglutination occurs.

Flow cytometry analysis of peripheral blood of a patient returns elevated B cell count and decreased T cell count. Which conditions could explain this result?

DiGeorge syndrome.

Progressive depletion of CD4+ T lymphocytes is associated with which condition?

It is associated with an increased likelihood of clinical complications from HIV/AIDS.

What does a positive HLA lymphocyte toxicity assay mean for the compatibility of donor and recipient?

If reaction is positive, the two tissues are incompatible in their HLA groups, which may cause unsuccessful tissue transplantation.

This test helps provide histocompatibility typing of tissue recipients and donors and can help genetic counseling and paternity testing.

HLA test (lymphocyte toxicity assay).

Test used to evaluate the ability of lymphocytes to actively multiply in response to a foreign antigen or mitogen to assess immunocompetence.

Lymphocyte Transformation Assay.

In a lymphocyte transformation assay, what does a low stimulation index or unresponsiveness indicate?

A depressed or defective immune system.

True or False: a lymphocyte co-culture with a high stimulation index indicates good compatibility.

False, it indicates poor compatibility.

What does elevated levels of IgM in a newborn indicate?

In utero infection such as rubella, STD.

Autoimmune condition associated with increased serum IgG, IgA, and IgM.

Lupus.

This immunoglobulin is present in all acute infections.

IgM.

What is a sandwich ELISA?

It is an assay that uses a capture antibody bound to the bottom of the plate to sequester a specific antigen. A primary and secondary antibodies are added on top to detect bound antigen.

What is an auto-antibody?

An antibody produced by the immune system that is directed against one or more of the individual's own proteins or nucleic material.

True or False: A negative ANA test excludes the diagnosis of Lupus while a positive ANA test confirms the diagnosis.

False. A positive ANA test has to be further confirmed by other tests.

A positive anti-mitochondrial antibodies test is linked to which condition(s)?

Biliary cirrhosis and autoimmune liver diseases.

What does anti-thyroid peroxidase antibody (anti-TPO) test assess?

Thyroid autoimmune conditions (Hashimoto's and Graves' disease).

Golden test used to detect rheumatoid arthritis?

Rheumatoid factor.

True or False: The RF test is directed towards identification of RF which is an IgG antibody.

False. The test detects the IgM antibodies that react with RF.

What are the Autoantibodies associated with LADA?

Glutamic acid decarboxylase autoantibodies (GADA). Insulinoma-associated IA-2 autoantibodies, Zinc transporter autoantibodies.

Which antibody can distinguish between Type 2 Diabetes and LADA?

GADA.

True or False: The intra-dermal allergy test is a scratch test where allergens are injected into the epidermis.

False. Dermis.

Allergy blood testing relies on blood serum levels of this molecule.

IgE.

Common method of measurement of IgE levels in the blood using radiolabeled anti-IgE antibodies.

The radioallergosorbent test (RAST).

A patient with a blood pressure of 145/92 is categorized as having___.

Type 2 hypertension.

True or False: S : Dub of “Lub-Dub” is caused by the closure of semi lunar valves.

True.

What is EKG used to evaluate?

Arrhythmias, Myocardial injury and damage, Conduction defects, Hypertrophy, Pericardial diseases, Non-cardiac conditions such as electrolyte abnormalities, pulmonary diseases.

What are common methods of stressing the heart?

Exercise, chemicals, and pacing.

What is Cardiac nuclear scanning used to detect?

Accurate measurement of cardiac output, Coronary artery occlusive disease, Decreased myocardial function.

What is echocardiography useful for?

Heart wall motion and abnormalities, Valvular disease, Heart during stress testing, Identify and quantify pericardial fluid.

Cardiac injury biomarker that becomes elevated very early (2-3 hours after cardiac muscle injury) and remains elevated up to 2 weeks after initial injury.

Troponin.

What does elevated creatine kinase in the blood indicate?

Myocardial injury, neurologic or skeletal muscle diseases.

Which creatine kinase is specific to the heart?

CK-MB.

The levels of this enzyme can rise within 6 hours after damage and if damage is not persistent, levels peak by 18 hours and return to normal in 2-3 days.

Creatine kinase.

What advantage does myoglobin provide over CK-MB?

Serum levels of myoglobin are elevated after 3 hrs (earlier than CK-MB) which allows for thrombolytic therapy to be started if injury confirmed. Thrombolytic therapy should be started within 6 hours after an MI.

True or False: Elevated lactate dehydrogenase 1 (LDH1) marker is used to confirm myocardial damage early to start thrombolytic therapy.

False. LDH1 levels elevated may indicate myocardial injury that may have occurred in the last 24-48 hrs which is too late to start thrombolytic treatment.

Technique used to locate the region of coronary occlusion in patients with positive stress test results.

Cardiac Catheterization (coronary angiography).

True or False: CT angiography is an invasive technique that provides information about the patency of heart vessels.

False. Non-invasive.

True or False: Individuals with Agatson score of >400 have an increased occurrence of coronary procedures due to plaque calcification.

True.

When elevated in the blood, this lipoprotein provides protection against CAD.

HDL.

What are the three pillars of the Virchow’s triad?

Vessel wall injury, Stasis (sluggish blood flow), Hypercoagulability.

Congenital or acquired abnormality of blood coagulation that increases the risk of thrombosis is termed?

Thrombophilia (hypercoagulability).

What is the function of thrombin in the coagulation cascade?

Converting fibrinogen into active fibrin.

What is the function of plasmin in the coagulation cascade?

Fibrinolysis at when the clot is no longer necessary by breaking down fibrin into fragments (FDP) including D-dimer.

Elevated level of this protein fragment in the plasma is a useful indicator of thrombosis (e.g. deep vein thrombosis [DVT] and/or pulmonary embolism [PE]).

D-Dimer.

True or False: A negative D-dimer result can always safely rule out thromboembolism.

False. False negative can occur if blood sample is taken too early after thrombosis or delayed several days.

What is the function of proteins S and C?

They are part of the body’s natural anticoagulation system.

Mutation in this factor prevents it from responding to inactivation of clotting cascade by body’s natural (protein C) anticoagulant system.

Factor V Leiden.

These conditions are associated with acquired thrombophilia.

Anti-phospholipid syndrome (Lupus), cancer, sickle cell anemia, heparin-induced thrombocytopenia (HIT).

_ is a predisposition to blood clots, while __ is a condition of low platelets.

Thrombophilia - thrombocytopenia.

How is Hemophilia A diagnosed?

Deficiency of coagulation factor VIII.

Vascular disease forming patches of petechiae or pinpoint hemorrhages, on the skin, usually caused by autoimmune disease and inflammation of blood vessels.

Vascular purpura.

Xenon gas is used in this imaging technique to evaluate ventilation.

Nuclear lung scan.

True or False: Examinations of sputum or bronchoalveolar lavage specimens are cytological examinations whereas examination of lung biopsy specimens are histological examinations.

True.

Lung disease associated with deficient α1-antitrypsin.

Inherited emphysema.

Manifested by increased resistance to airflow while results from decreased lung expansion.

Obstructive – Restrictive.

What are considered routine pulmonary tests?

Spirometry, Measurement of airflow rates, Calculation of lung volumes and capacities.

These tests can be requested by the clinician if routine PFTs are not conclusive.

Gas diffusion and inhalation tests.

How do you calculate functional residual capacity?

Sum of expiratory reserve volume and residual volume (ERV+RV).

Which portion of the lungs does not participate in gas exchange and accounts for the dead space?

Trachea, bronchi, bronchioles.

True or False: The forced expiratory volume in 1 second (FEV1) is considerably increased in obstructive lung diseases such as asthma.

False. Decreased.

Maximal rate of airflow through the pulmonary tree during forced expiration (Maximal mid-expiratory flow (MMEF) is not affected in which disease(s)?

Pulmonary restrictive diseases.

In a gas exchange study, the diffusing capacity of the lung is measured by having the patient inhale small amounts of which gas?

Carbon monoxide (CO).

AP has severe pneumonia (a restrictive pulmonary disease) which means that his lungs cannot expand as much as they should. How are lung volumes and diffusion capacity affected?

May have reduced lung volumes but normal airflow rates.

AB has pulmonary fibrosis. How are lung volumes and diffusion capacity affected?

Lung volumes and capacities are reduced; Diffusing capacity markedly reduced.

What does Arterial oxygen saturation (SaO2) measure?

Represents the percentage of hemoglobin saturated with oxygen.

True or False: Patients in whom venous blood mixes prematurely with arterial blood have an increased PaO2.

False. Decreased.

What is the principle of Oximeter use?

Oxygenated blood absorbs more infrared light and allows more red light through. Oximeter transmits red and infrared light from one side and records the amount of light from the other side.

These conditions are associated with increased PaO2 and O2 content.

Hyperventilation and polycythemia.

How is sleep apnea monitored and diagnosed?

By using a sleep laboratory that monitors pauses in breathing or periods of shallow breathing during sleep.

Condition of increased blood pressure within the arteries of the lungs (mean arterial pressure >25 mm Hg).

Pulmonary hypertension.

How is Pulmonary hypertension diagnosed?

Echocardiography and right heart catheterization.

True or False: Neurohypophysis produces and releases ADH and Oxytocin.

False. Hypothalamus (neurosecretory neurons) produces ADH and Oxytocin. Neurohypophysis stores and releases them when needed.

Which hypothalamic hormone controls/inhibits growth hormone production?

Somatostatin.

Parathyroid hormone stimulates bone, Calcium absorption from the , and Calcium reabsorption from the __.

Parathyroid hormone stimulates bone resorption, Calcium absorption from the gut, and Calcium reabsorption from the kidney.

Which type of Diabetes stems from Autoimmune destruction of beta cells in the pancreas?

Type 1 DM.

Which type of DM is not linked to obesity?

Type 1 DM.

Type of DM non-insulin-dependent.

Type II DM.

True or False: Screening for Type II diabetes is recommended starting at the age of 45 for overweight adults with additional risk factors.

False. It is recommended sooner if adult is overweight and has additional risk factors.

Where can fasting blood be measured?

Whole blood, plasma or serum.

Increased fasting glucose level is associated with which disorders?

Diabetes mellitus (DM), Acute stress response, Cushing syndrome, Chronic renal failure.

How does insulinoma affect fasting blood glucose test?

Decreases fasting blood glucose levels.

Test done by measuring the amount of glucose in patients’ blood 2 hours after a meal is ingested.

Postprandial blood glucose test.

True or False: Hypothyroidism is associated with increased postprandial glucose test.

False. Decreased.

What is the difference between a postprandial glucose test and a glucose tolerance test?

In a Postprandial test, glucose is measured 2 hours after a regular meal while in a glucose tolerance test, the patient is asked to ingest an Oral glucose solution (75 grams of glucose) and glucose levels are measured 30 min, 1 h into 4 hours.

True or False: In order to diagnose DM, at least one glucose test should be positive for the diagnosis.

False. A diagnosis of diabetes mellitus can be made on the basis of the results from 2 tests.

Which type of hemoglobin combines most strongly with glucose and contains the majority of glycosylated Hb?

HbA1c.

What indicator is most helpful in evaluating long-term blood glucose management in patients with diabetes mellitus?

Glycosylated hemoglobin levels (HbA1c).

Which condition(s) is/are not associated with increased HbA1c?

Hemolytic anemia, Chronic blood loss, RBC survival is shortened, Chronic renal failure.

The combination of which two tests will provide a very accurate diagnosis of insulinoma (insulin-producing tumor of the pancreas)?

Fasting blood glucose and insulin assay.

What does excess of insulin production in response to glucose tolerance testing predict?

Type 2 Diabetes years before hyperglycemia is documented.

What are decreased levels of C-peptide associated with?

Factitious hypoglycemia and Type 1 diabetes mellitus.

True or False: A patient with diagnosed Glucagonoma will show increased levels of Glucagon and hyperglycemia.

True.

Low TSH and T3/T4 and high TRH levels are associated with which condition?

Secondary hypothyroidism.

True or False: Since T3 is more stable than T4, it is used as the test of choice to diagnose hypothyroidism.

False. T4 is more stable and therefore used to diagnose hypothyroidism.

These molecules transactivate the TSH receptors and cause the stimulation of the thyroid gland independent of normal feedback stimulation.

Thyroid-stimulating immunoglobulins (TSI).

Which conditions are associated with decreased T3/T4 levels?

Hypothyroid states, Pituitary insufficiency, Hypothalamic failure, Iodine insufficiency.

Why are patients with chronic renal failure monitored for increased PTH levels (hyperparathyroidism)?

Vitamin D which facilitates Calcium uptake by the gut matures in the kidney. Also, the kidney does not excrete phosphate which accumulates in the blood and sequesters calcium.