How are Type IV hypersensitivity reactions different from all other types (I, II, or III) of hypersentivity reactions?
The usual types of reactions are mediated by antibodies.
B-lymphocytes produce the offending substances.
They typically occur with the first exposure to an antigen.
Delayed reactions are characterized by cytokine release.
The Correct Answer is A
A) The usual types of reactions are mediated by antibodies:
Correct. Types I, II, and III hypersensitivity reactions are mediated by antibodies (IgE, IgG, or IgM) that bind to antigens and trigger immune responses. In contrast, Type IV hypersensitivity reactions are T-cell mediated and do not involve antibodies.
B) B-lymphocytes produce the offending substances:
This statement is incorrect. B-lymphocytes are involved in antibody-mediated immune responses (types I, II, and III hypersensitivity reactions), not Type IV hypersensitivity reactions, which are primarily mediated by T-lymphocytes.
C) They typically occur with the first exposure to an antigen:
This statement is incorrect. Type IV hypersensitivity reactions usually require sensitization upon initial exposure to an antigen, and subsequent exposures elicit the delayed hypersensitivity response. This is similar to types I, II, and III hypersensitivity reactions, which also involve sensitization upon initial exposure.
D) Delayed reactions are characterized by cytokine release:
This statement is partially correct. Type IV hypersensitivity reactions are characterized by a delayed onset (typically 24 to 72 hours after exposure) and involve the release of cytokines from activated T-lymphocytes, leading to inflammation and tissue damage. However, other types of hypersensitivity reactions may also involve cytokine release, so this feature alone does not differentiate Type IV from other types of reactions.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is D
Explanation
A) The drug may be needed to treat a sudden systemic allergic reaction:
While cortisol may play a role in managing allergic reactions by suppressing inflammation, the primary reason for carrying a cortisol kit in Addison's disease is not typically related to managing allergic reactions.
B) Hypertensive crisis requires immediate treatment to prevent a stroke:
Hypertensive crisis may occur in some individuals with Addison's disease due to adrenal insufficiency, but the immediate treatment for this would typically involve fluids and intravenous hydrocortisone rather than carrying a cortisol kit for self-administration.
C) Hyperglycemia may require cortisol to lower the blood glucose level:
Cortisol can indeed influence blood glucose levels, but the need to carry a cortisol kit is primarily related to the management of adrenal insufficiency rather than hyperglycemia alone.
D) Stress increases the body's need for additional replacement hormone:
Correct. Individuals with Addison's disease have insufficient production of cortisol and often also lack aldosterone. During times of stress, such as illness, trauma, or surgery, the body's demand for cortisol increases to help cope with the stress. Inadequate cortisol production during stress can lead to adrenal crisis, a life-threatening condition. Therefore, carrying a cortisol kit allows the individual to promptly administer additional replacement hormone (usually hydrocortisone) during times of stress to prevent adrenal crisis.
Correct Answer is A
Explanation
Gout is a type of inflammatory arthritis caused by the deposition of monosodium urate crystals in the joints and surrounding tissues. Here's an explanation of the pathophysiological process producing the symptoms of gout:
A) Deposition of crystals in the synovial space of the joints produces inflammation and irritation:
Correct. In gout, elevated levels of uric acid in the blood lead to the formation and deposition of monosodium urate crystals in the synovial fluid of joints, particularly in the big toe joint (first metatarsophalangeal joint) in many cases. These crystals trigger an inflammatory response, activating immune cells and causing swelling, redness, warmth, and severe pain in the affected joint. The inflammation and irritation result from the body's immune response to the presence of these crystals.
B) Chondrocyte injury destroys joint cartilage, producing osteophytes and joint inflammation:
This option describes a process more characteristic of osteoarthritis, where degeneration of joint cartilage leads to the formation of osteophytes (bone spurs) and joint inflammation. Gout involves the deposition of urate crystals rather than direct chondrocyte injury.
C) An immune complex and autoantibody deposition in connective tissue results in inflammation:
This process describes the pathophysiology of autoimmune diseases such as rheumatoid arthritis, where immune complexes and autoantibodies contribute to inflammation and tissue damage. In gout, the inflammation is primarily triggered by the deposition of urate crystals rather than immune complex deposition.
D) An autoimmune inflammation involving IgG response to an antigen causes joint destruction:
This option describes the autoimmune process seen in diseases like rheumatoid arthritis, where antibodies target specific antigens, leading to joint destruction. Gout is not an autoimmune disease, and joint destruction in gout is primarily due to inflammation caused by urate crystal deposition rather than autoimmune mechanisms.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.
