Mod. 1 Immunity (autoimmunity) Flashcards
A 32-year-old woman presents with a history of chronic fatigue, joint pain, and a butterfly-shaped rash across her cheeks. Blood tests reveal a positive antinuclear antibody (ANA) test with a titer of 1:160. Based on the diagnostic criteria for Systemic Lupus Erythematosus (SLE), which of the following is most likely true?
A) The patient must meet a minimum of 10 diagnostic criteria for an SLE diagnosis.
B) The ANA test result is sufficient to confirm the diagnosis of SLE.
C) The patient likely has a severe form of SLE based on the ANA titer alone.
D) A score of 6 or more of the 22 criteria should raise suspicion of SLE in this patient.
D
Explanation: A diagnosis of SLE is strongly suggested when a patient meets 10 or more of the 22 criteria. A positive ANA test (titer of at least 1:80) is one of the key diagnostic criteria, but further evaluation of other symptoms is required.
Autoimmunity Mechanism Which of the following most accurately describes the mechanism underlying autoimmunity?
A) The immune system fails to recognize self-antigens and mounts an immune response against the body’s own tissues.
B) The immune system reacts to an infection but fails to activate a response against self-antigens.
C) The immune system develops a tolerance to abnormal cells, leading to increased autoantibody production.
D) The immune system is unable to recognize foreign antigens, resulting in chronic inflammation.
A
Explanation: Autoimmunity occurs when the immune system fails to recognize its own tissues as “self,” triggering an immune response that targets the body’s own cells or tissues.
Immunodeficiency Diagnosis A patient with a history of recurrent pneumonia and chronic sinusitis undergoes blood tests showing low levels of immunoglobulin and reduced B- and T-cell counts. Which of the following is most likely indicated by these findings?
A) Primary immunodeficiency due to genetic factors.
B) A secondary immunodeficiency due to acquired factors such as a viral infection.
C) Acute inflammation in response to a bacterial infection.
D) A typical immune response to ongoing bacterial infection.
A
Explanation: A primary immunodeficiency typically refers to congenital defects in immune function, leading to recurrent infections. The low immunoglobulin levels and abnormal B- and T-cell counts suggest an underlying immune deficiency.
A 28-year-old male diagnosed with HIV presents with a persistent cough, weight loss, and fever. Blood work reveals a CD4 count of 150 cells/mm³. Which of the following is the most appropriate action in managing this patient’s condition?
A) Begin highly active antiretroviral therapy (HAART) to address viral replication.
B) Initiate intravenous antibiotics to treat a potential bacterial pneumonia.
C) Evaluate for the presence of opportunistic infections and treat accordingly.
D) Recommend regular immunizations to prevent future infections.
C
Explanation: A CD4 count below 200 cells/mm³ is diagnostic for AIDS. At this stage, patients are highly susceptible to opportunistic infections. A thorough evaluation and treatment for opportunistic infections, such as Pneumocystis jirovecii pneumonia, are crucial.
HIV Transmission and Prevention A nurse is providing education to a group of patients at risk for HIV. Which of the following statements about HIV transmission and prevention is most accurate?
A) HIV is primarily transmitted through casual contact, such as handshakes or hugging.
B) The use of pre-exposure prophylaxis (PrEP) medications can reduce the risk of HIV transmission.
C) Antiretroviral therapy (ART) is only effective after symptoms of HIV infection appear.
D) HIV can be transmitted only through sexual contact, not through blood.
B
Explanation: Pre-exposure prophylaxis (PrEP) medications, when used correctly, can significantly reduce the risk of acquiring HIV. HIV transmission primarily occurs through blood and bodily fluids, including sexual contact, sharing needles, and from mother to child during childbirth or breastfeeding.
Immune System and Stress Response Which of the following is a correct statement regarding the effect of chronic stress on the immune system?
A) Chronic stress enhances immune response by increasing the production of antibodies.
B) Chronic stress suppresses the immune system, making individuals more susceptible to infections.
C) Chronic stress results in a permanently enhanced immune response to infections.
D) Chronic stress has no impact on the immune system.
B
Explanation: Chronic stress suppresses immune function, increasing the vulnerability to infections and potentially exacerbating autoimmune disorders. This occurs due to the prolonged release of cortisol, which inhibits certain immune responses.
Aging and Immune Function Which of the following describes a characteristic change in immune function as individuals age?
A) A marked increase in the production of B- and T-cells.
B) An increase in apoptosis of B- and T-cells and a reduced immune response.
C) Enhanced immune responses, leading to fewer chronic illnesses.
D) No significant changes in immune function with aging.
B
Explanation: Aging leads to a decline in immune function, a phenomenon known as immune senescence. This includes a reduction in the production of new B- and T-cells and an increase in apoptosis, making older adults more susceptible to infections and autoimmune diseases.
Treatment of Autoimmune Disease Which of the following treatment options is most commonly used for managing autoimmune conditions like Systemic Lupus Erythematosus (SLE)?
A) Antibiotics to target the infectious agent.
B) Immunosuppressive agents to reduce autoantibody production.
C) Antifungal medications to prevent secondary infections.
D) Antipyretics to reduce fever and inflammation only.
B
Explanation: Immunosuppressive agents, such as corticosteroids, antimalarials, and DMARDs, are commonly used to reduce the activity of the immune system and manage the symptoms of autoimmune diseases like SLE.
A nurse is reviewing the laboratory results of a patient suspected of having an immunodeficiency disorder. Which finding would be most indicative of a primary immunodeficiency rather than a secondary immunodeficiency?
A) CD4+ count of 150 cells/mm³ in a patient with a history of untreated HIV
B) Recurrent pneumonia, sinusitis, and otitis media since infancy with low B-cell counts
C) Decreased neutrophil count following chemotherapy for leukemia
D) A history of tuberculosis reactivation in a patient receiving chronic corticosteroids
B) Recurrent pneumonia, sinusitis, and otitis media since infancy with low B-cell counts
Rationale: Primary immunodeficiency disorders are congenital and often present in infancy or early childhood with recurrent infections, particularly involving B or T-cell deficiencies. Secondary immunodeficiencies result from external factors, such as chemotherapy (C) or chronic steroid use (D). A low CD4+ count in an HIV-positive patient (A) suggests secondary immunodeficiency due to HIV infection.
A nurse is caring for a patient with HIV/AIDS who presents with progressive neurological symptoms, including confusion and memory loss. The nurse anticipates that the provider will order which diagnostic test to confirm the suspected complication?
A) CD4+ count and viral load
B) MRI of the brain with contrast
C) Lumbar puncture for cerebrospinal fluid analysis
D) Western blot for HIV confirmation
B) MRI of the brain with contrast
Rationale: HIV/AIDS can lead to neurological dysfunction, including AIDS dementia complex and progressive multifocal leukoencephalopathy (PML). An MRI of the brain with contrast is the preferred imaging modality to detect characteristic white matter lesions and exclude other causes. While CD4+ count and viral load (A) help assess disease progression, they do not specifically diagnose neurological involvement. Lumbar puncture (C) may be useful in certain infections like cryptococcal meningitis but is not first-line for PML. Western blot (D) is used for initial HIV confirmation, not for AIDS-related neurological complications.
A patient with a recent HIV diagnosis asks the nurse about their prognosis. The nurse explains that disease progression is primarily monitored by which of the following laboratory tests?
A) Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)
B) CD4+ count and HIV viral load
C) Complete blood count (CBC) and platelet count
D) Serum immunoglobulin levels and B-cell count
B) CD4+ count and HIV viral load
Rationale: The progression of HIV is monitored using CD4+ count (to assess immune function) and HIV viral load (to determine the level of viral replication). ESR and CRP (A) indicate general inflammation but do not monitor HIV progression. CBC and platelet count (C) can be altered in advanced disease but are not primary markers of progression. Immunoglobulin levels and B-cell counts (D) are more relevant for assessing primary immunodeficiencies, not HIV/AIDS.
A patient with advanced HIV infection has a CD4+ count of 180 cells/mm³. Based on this result, the nurse should anticipate which of the following interventions?
A) Administration of pneumococcal and influenza vaccines
B) Initiation of prophylactic antibiotics for Pneumocystis jirovecii pneumonia (PJP)
C) Discontinuation of all antiretroviral medications to reduce viral resistance
D) Administration of gamma-globulin therapy for immune support
B) Initiation of prophylactic antibiotics for Pneumocystis jirovecii pneumonia (PJP)
Rationale: Patients with a CD4+ count below 200 cells/mm³ are at high risk for opportunistic infections, particularly PJP, and require prophylactic treatment with trimethoprim-sulfamethoxazole (TMP-SMX). Vaccines (A) are typically administered earlier in HIV progression before significant immunosuppression. Discontinuing antiretroviral therapy (C) would worsen immunosuppression. Gamma-globulin (D) is used for B-cell deficiencies, not for HIV-related immunosuppression.
B) Initiation of prophylactic antibiotics for Pneumocystis jirovecii pneumonia (PJP)
Rationale: Patients with a CD4+ count below 200 cells/mm³ are at high risk for opportunistic infections, particularly PJP, and require prophylactic treatment with trimethoprim-sulfamethoxazole (TMP-SMX). Vaccines (A) are typically administered earlier in HIV progression before significant immunosuppression. Discontinuing antiretroviral therapy (C) would worsen immunosuppression. Gamma-globulin (D) is used for B-cell deficiencies, not for HIV-related immunosuppression.
D) “Using condoms inconsistently is still effective at reducing my partner’s risk of acquiring HIV.”
Rationale: Consistent condom use is necessary to effectively reduce HIV transmission risk. Intermittent or inconsistent use still poses a significant risk of transmission. Antiretroviral therapy (A) significantly reduces viral load and transmission risk. An undetectable viral load (B) means HIV is not sexually transmissible (U=U: undetectable = untransmittable). Male circumcision (C) has been shown to reduce heterosexual HIV transmission.
Which of the following patients is at the highest risk of developing an opportunistic infection?
A) A 36-year-old patient receiving chemotherapy for breast cancer with an absolute neutrophil count (ANC) of 800/mm³
B) A 45-year-old patient on long-term corticosteroids for rheumatoid arthritis
C) A 28-year-old patient with HIV and a CD4+ count of 90 cells/mm³
D) A 60-year-old patient with uncontrolled type 2 diabetes and recurrent skin infections
C) A 28-year-old patient with HIV and a CD4+ count of 90 cells/mm³
Rationale: A CD4+ count below 200 cells/mm³ is a defining criterion for AIDS and indicates severe immunosuppression, putting the patient at highest risk for opportunistic infections. An ANC of 800/mm³ (A) suggests moderate neutropenia but not as profound as the immunosuppression seen in advanced HIV. Long-term steroid use (B) increases infection risk, but not to the same extent as a critically low CD4+ count. Uncontrolled diabetes (D) impairs wound healing and immune response but is not the most immunocompromised state.
