Secondary Immunodeficiencies Flashcards
Differentiate between primary and secondary immune deficiencies
Primary immunodeficiencies are caused by defects which originate in the immune system itself.
Secondary immunodeficiencies are due to insufficiency of a supporting component of the immune system or an external or “secondary” depleting factor.
How does diabetes impair the immune system?
Hyperglycemia affects neutrophil function
Poor circulation leads to skin ulceration, less delivery of immune cells to wounds
In diabetes, the defect in ______ function is most prominent
Neutrophil
List common infections that are seen with increased severity and frequency in diabetics
Pneumonia UTI Cellulitis Diabetic foot ulcers Candida
List some unusual infections that can be complications of diabetes
Deep candida infections Rhinopulmonary zygomycosis (mucormycosis) Malignant otitis media due to Pseudomonas aeruginosa
_______ is better explained as a state of immune modulation than immune deficiency
Pregnancy
Give some mechanisms for altered immunity in pregnant women
Progesterone has been shown to inhibit lymphocyte proliferation in vitro.
Uromodulin is a pregnancy-specific serum factor which has
also been shown to inhibit B cell activity (antibody responses are generally preserved)
Depressed T cell responses
List infections that pregnant women are at increased risk for
HAV, HBV influenza herpesviruses chlamydia/ gonococcus listeria campylobacter TB malaria
How does protein-calorie malnutrition affect immune function
global metabolic and hormonal disturbances of
starvation.
low levels of leptin may be involved in the immune dysregulation
deficient intake of protein, fat, vitamins, and minerals, particularly nutritional deficiencies of zinc, iron, folate, pyridoxine, and vitamin A.
Malnutrition leads to a 10x risk of mortality from ____ and a 30x increased risk of mortality from _____
pneumonia and gastroenteritis
Older people are at risk of ______ reactivation due to changes in lymphocyte development and function
zoster
complication= post-herpetic neuralgia
Older adults can have a decrease in _______ function and thus an increase in auto-reactivity
Suppressor cell
How do trauma and critical illness affect immunity?
Massive release of inflammatory cytokines, activation of monocytes and macrophages
_____ are particularly immunosuppressive due to the massive loss of protein and disruption of physical barriers
Burns
How does stress impact immunity?
Reduced NK cell activity
Depressed lymphocyte mitogen responses
Endogenous glucocorticoids
In ESRD, shunting of portal blood reduces the ability of ______ to clear opsonized material and can also cause hypocomplementemia. Furthermore, decreased hepatic metabolism of __________ is likely immune suppressive
Kupffer cells
decreased metabolism of endogenous glucocorticoids
List unusual infections assocaited wiht cirrrhosis
Cryptococcal infection
Candidal infection
Infection with vibrio vulnificus
Gastritis and any other protein losing condition can result in ________. Examples include nephritic syndrome, IBD, Celiac, massive lymphedemia, peritoneal dialysis, burns
hypogammaglobulinemia
List hematologic/ oncologic conditions associated with B cell deficiency
Multiple myeloma
Waldenstrom’s macroglobulinemia
Chronic lymphocytic leukemia
Well differentiated lymphomas
List hematologic/ oncologic conditions associated with T cell deficiency
Hodgkins
Advanced solid tumors
How does sickle cell anemia act as an immune suppressive condition?
Functionally asplenic–> increased risk of infection with encapsulated organisms
The immune suppression associated with blood transfusions is not seen in _____-____ blood
leukocyte-depleted
Describe the immune suppressive effects of measles infection
possibility of superinfection
- T cell lymphopenia with depletion of T-dependent areas of lymph nodes and spleen
- Cutaneous anergy
- Diminished in vitro T cell proliferation with mitogens or alloantigens
- Diminished antibody production
How does HTLV-1 cause immune suppession?
can produce adult T cell leukemia/lymphoma.
Patients with ATL present with severe immune defects and multiple opportunistic infections
_____ infection places transplant patients at risk for other opportunistic infections like PCP, aspergillosis, organ rejection
CMV
How to bacterial superantigens modulate the immune system?
- bind simultaneously to MHC class II antigens and to the non-antigen-binding region of T cell receptor variable regions, thereby stimulating massive numbers of T cells.
- These T cells then produce inflammatory cytokines, which lead to a syndrome resembling septic shock with multisystem organ failure.
- After “hyper activation” these T cells become anergic and can no longer become activated.
How do mycobacteria inhibit the immune system
Replicated within monocytes and macrophages, inhibit the ability of the infected cell to kill invaders and coordinate the immune response
Increased risk of secondary infection
Malaria + EBV=
Burkitt lymphoma
List some rheumatologic conditions associated with increased susceptibility to infection, even in the absence of immune suppressing medications
SLE, RA, granulomatosis with polyangiitis
Patients receiving ______ have reduced T cell function, diminished antibody production, and deficient neutrophil function
hemodialysis
List three renal functions associated with immune suppression
nephrotic syndrome
ESRD
Uremia
List some drugs that have immunesuppressing effects
Glucocorticoids
Signal transduction inhibitors: cyclosporine, tacrolimus, sirolimus
Purine synthesis inhibitors: azathioprine, mycophenolate mofetil
Antibodies: TNF inhibitors
Use of TNF inhibitors places patients at increased risk of:
granulomatous infections like mycobacteria and endemic fungi
