A 78-year-old woman comes to the office due to fever, headache, sore throat, cough, and severe myalgias for 24 hours. Her medical problems include hypertension and Alzheimer dementia. Her family came to visit over the weekend, and her grandson had symptoms of a cold. The patient's temperature is 38.9 C (102 F). Lung examination is unremarkable. A nasal specimen swab is positive for influenza. The patient is started on oseltamivir. Which of the following is most likely impaired in the patient's infected cells as a result of the treatment?

Question

A 78-year-old woman comes to the office due to fever, headache, sore throat, cough, and severe myalgias for 24 hours.  Her medical problems include hypertension and Alzheimer dementia.  Her family came to visit over the weekend, and her grandson had symptoms of a cold.  The patient's temperature is 38.9 C (102 F).  Lung examination is unremarkable.  A nasal specimen swab is positive for influenza.  The patient is started on oseltamivir.  Which of the following is most likely impaired in the patient's infected cells as a result of the treatment?

Quizplus · Accepted Answer

11ec160b_3bf8_91cb_9249_c3d56e3ffef7_MD0001_00 Oseltamivir is a neuraminidase inhibitor useful in the treatment of both influenza A and B virus infections. Neuraminidase is required for the release of virus from infected cells and for the spread of virus within the respiratory tract. Neuraminidase inhibitors cause the newly synthesized virions to adhere to the host cell surface and form viral aggregates, thereby reducing the spread of virus to other host cells. Oseltamivir (Tamiflu) can shorten the course and complications of influenza A and B infections if taken within 48 hours of the onset of symptoms. In addition, oseltamivir works to slow viral penetration of the mucous secretions that protect the respiratory epithelium. Oseltamivir can therefore be used to treat or prevent influenza. (Choice A) The influenza viral genome consists of segmented RNA, which is translated predominantly into individual proteins rather than a large polyprotein product. HIV protease inhibitors (eg, darunavir) are used to counteract HIV polyprotein cleavage mediated by viral protease. (Choice B) Foreign (viral) protein synthesis can be inhibited by α- and β-interferons, which induce the synthesis of proteins that have an antiviral effect. These antiviral proteins promote the degradation of RNA and halt protein translation in virally infected cells only. (Choice C) Impairment of viral RNA replication is accomplished by the reverse transcriptase inhibitors used to combat HIV (eg, abacavir, tenofovir, zidovudine). (Choice D) Amantadine (limited use in influenza management due to viral resistance) impairs uncoating or disassembly of the influenza A virion after host cell endocytosis. Oseltamivir does not operate via the same mechanism of action. Currently, amantadine is mainly used in Parkinson disease as it increases dopamine release (unclear mechanism). Educational objective: Oseltamivir is a neuraminidase inhibitor useful in the treatment and prevention of both influenza A and B virus infections. This medication impairs the release of newly formed virions from infected host cells and impairs viral penetration of mucous secretions that overlie the respiratory epithelium.

A 78-Year-Old Woman Comes to the Office Due to Fever