NR565 Week 1 Discussion
Professor and class,
Before initiating abacavir, an anti-retroviral, for a newly diagnosed HIV positive
patient the nurse practitioner orders HLA-B*5701 allele genetic testing. The test
confirms that the patient carries the HLA-B*5701 allele.
The HLA-B*5701 is genetic testing used to determine the potential risk for severe side
effects from the antiviral medication abacavir (De Spiegelaere et al., 2015). The HLA-B
gene has an impact on how the immune system responds and recognizes various
pathogens while mediating hypersensitivity reactions (De Spiegelaere et al., 2015). If a
copy of the HLA-B*5701 is positive, it determines there is at least one copy of the allele.
This test is run by obtaining a sample of the patient's saliva or blood. Abacavir is a
nucleoside reverse transcriptase inhibitor used as an antiretroviral therapy in HIV
patients (De Spiegelaere et al., 2015). Due to this drug having a hypersensitive reaction
to patients that are HLA-B*5701 carriers, the FDA has recommended all providers pre-
screen their patients before prescribing this medication in the treatment of HIV patients
(De Spiegelaere et al., 2015).
In this scenario, the patient carries the HLA-B*5701 allele; therefore, they should not be
prescribed abacavir. The side effects of a patient receiving abacavir that test positive for
the HLA-B*5701 allele can be fatal (De Spiegelaere et al., 2015). Additionally, they may
exhibit symptoms that include a fever, rash, vomiting, and shortness of breath (De
Spiegelaere et al., 2015).
A patient is prescribed antiplatelet therapy (clopidogrel) following an acute
myocardial infarction (MI). Six months later, the patient suffers another acute MI.
The patient has been adherent to therapy and the nurse practitioner suspects
that clopidrogel may have been ineffective. How might genetic
testing have been beneficial in this case?
For the last ten years, I have been working in the cardiac Cath Lab. Antiplatelet therapy
is a crucial aspect of positive patient outcomes. Plavix (clopidogrel) is an antiplatelet
drug that inhibits the ability of platelets from sticking together, preventing clot formation.
Plavix has been a gold standard for patients that receive coronary interventions. If a
patient has another cardiac event, we use P2Y12 blood samples to determine if the
patient is responsive to Plavix. When a patient is resistant to Plavix, it generally means
the CYP2C19 gene is nonfunctional (Moon et.al., 2018). When the CYP2C19 gene is
nonfunctional, it cannot convert Plavix to its active form (Moon et.al., 2018).
In this scenario, pre-genetic testing could have determined if Plavix would have been an
effective Antiplatelet therapy for this patient. Unfortunately, patients that have genetic
variants of CYP2C19 have an increased risk for developing a major cardiac event,
stroke, and death (Moon et.al., 2018).
Identify 2 limitations of pharmacogenomics testing. Explain.
Professor and class,
Before initiating abacavir, an anti-retroviral, for a newly diagnosed HIV positive
patient the nurse practitioner orders HLA-B*5701 allele genetic testing. The test
confirms that the patient carries the HLA-B*5701 allele.
The HLA-B*5701 is genetic testing used to determine the potential risk for severe side
effects from the antiviral medication abacavir (De Spiegelaere et al., 2015). The HLA-B
gene has an impact on how the immune system responds and recognizes various
pathogens while mediating hypersensitivity reactions (De Spiegelaere et al., 2015). If a
copy of the HLA-B*5701 is positive, it determines there is at least one copy of the allele.
This test is run by obtaining a sample of the patient's saliva or blood. Abacavir is a
nucleoside reverse transcriptase inhibitor used as an antiretroviral therapy in HIV
patients (De Spiegelaere et al., 2015). Due to this drug having a hypersensitive reaction
to patients that are HLA-B*5701 carriers, the FDA has recommended all providers pre-
screen their patients before prescribing this medication in the treatment of HIV patients
(De Spiegelaere et al., 2015).
In this scenario, the patient carries the HLA-B*5701 allele; therefore, they should not be
prescribed abacavir. The side effects of a patient receiving abacavir that test positive for
the HLA-B*5701 allele can be fatal (De Spiegelaere et al., 2015). Additionally, they may
exhibit symptoms that include a fever, rash, vomiting, and shortness of breath (De
Spiegelaere et al., 2015).
A patient is prescribed antiplatelet therapy (clopidogrel) following an acute
myocardial infarction (MI). Six months later, the patient suffers another acute MI.
The patient has been adherent to therapy and the nurse practitioner suspects
that clopidrogel may have been ineffective. How might genetic
testing have been beneficial in this case?
For the last ten years, I have been working in the cardiac Cath Lab. Antiplatelet therapy
is a crucial aspect of positive patient outcomes. Plavix (clopidogrel) is an antiplatelet
drug that inhibits the ability of platelets from sticking together, preventing clot formation.
Plavix has been a gold standard for patients that receive coronary interventions. If a
patient has another cardiac event, we use P2Y12 blood samples to determine if the
patient is responsive to Plavix. When a patient is resistant to Plavix, it generally means
the CYP2C19 gene is nonfunctional (Moon et.al., 2018). When the CYP2C19 gene is
nonfunctional, it cannot convert Plavix to its active form (Moon et.al., 2018).
In this scenario, pre-genetic testing could have determined if Plavix would have been an
effective Antiplatelet therapy for this patient. Unfortunately, patients that have genetic
variants of CYP2C19 have an increased risk for developing a major cardiac event,
stroke, and death (Moon et.al., 2018).
Identify 2 limitations of pharmacogenomics testing. Explain.
