CPR APPLICATIONS FOUNDATION · CHAPTER 3 · TREATMENT
Treatment Foundations of Immunology
Use a chapter-level CPR map to organize how mechanism guides intervention, benefit, and predictable tradeoffs.
Supplemental foundation map: this page orients the detailed CPR Applications for Chapter 3. It is not part of the canonical CPR object inventory.
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Normal Foundations
Abnormal Foundations
Treatment Foundations · You are here
3.22 · SOURCE CPR FOUNDATION
Concept
Treatment foundations in immunology follow immune mechanism reversal. Hypersensitivity, autoimmunity, immunodeficiency, transplant rejection, and immunosuppression recur across organ systems, but the therapeutic logic remains stable. Identify whether the immune response is excessive, misdirected, or missing, and treat accordingly.
Pattern
Step 1 embeds immune disease inside kidney, lung, skin, GI, neurologic, or hematologic vignettes. Allergic disease requires mediator control, antibody-mediated disease requires reducing antibodies or B cells, T-cell disease requires cellular immune suppression, and immunodeficiency requires replacement or infection prevention. The organ gives context, but the immune mechanism chooses therapy.
Rule
- Name the immune mechanism first: decide whether the process is mast-cell mediated, antibody-mediated, immune complex–mediated, T-cell mediated, or immunodeficient.
- Classify the immune state: excessive activation, misdirected activation, and missing activation require different treatment logic.
- Choose the intervention that reverses the mechanism: block mediators, suppress lymphocytes, deplete B cells, neutralize antibodies, replace deficient components, or prevent infection.
Applications
- Anaphylaxis → immediate intramuscular epinephrine is first-line; antihistamines may relieve skin symptoms but never replace epinephrine; corticosteroids have no established acute rescue benefit
- Antibody cytopenia → steroids IVIG rituximab
- Immune complex disease → immunosuppression anti-inflammatory therapy
- T-cell disease → calcineurin inhibitors or steroids
- Selected antibody deficiencies → immunoglobulin replacement and individualized vaccination or infection-prevention strategy, based on the underlying defect
- Significant T-cell immunodeficiency → targeted infection prevention and specialist-guided vaccine safety; live-vaccine contraindications depend on the specific defect
- Transplant rejection prevention → T-cell immunosuppression
CPR APPLICATIONS · ACTIVE REASONING
Prioritize immune treatment
Choose the best explanation before opening feedback. These unscored self-checks do not save responses.
Decision 1: A patient has wheezing and hypotension shortly after allergen exposure.
Intramuscular epinephrine
Best explanation. It is the first-line medication for anaphylaxis, requiring prompt emergency management.
Antihistamine alone
Why this is less appropriate: Antihistamines do not reverse life-threatening airway or cardiovascular compromise.
Decision 2: A patient with a severe antibody-production defect has repeated invasive bacterial infections.
Immunoglobulin replacement when indicated
Best explanation. For selected significant antibody deficiencies, replacement and tailored prevention can address the underlying deficit.
Calcineurin inhibition
Why this is less appropriate: This suppresses T-cell activity rather than supplying deficient antibodies.
Decision 3: A drug inhibits pathologically activated lymphocytes.
Infection susceptibility may increase
Best explanation. Reducing harmful immune activity may also impair protective host responses.
All infection risk disappears
Why this is less appropriate: Immunosuppression is not antimicrobial eradication.
Transfer to a new scenario
Change one clinical finding, immune deficiency, microbial strategy or treatment context. Explain which mechanism changes and why; compare your reasoning against the explanations above.
Educational practice only; not individualized clinical guidance.
How to use this foundation map
- Read the Concept and identify the organizing mechanism.
- Use the Pattern to recognize how the mechanism tends to appear in Step 1-style reasoning.
- Restate the Rule without looking, then test whether each application follows from it.
- Move to the adjacent foundation layer or use question practice to test transfer.
When applying the organized knowledge to a case or question, pair CPR with the 5P Approach™.
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