Virology-Final.pdf

Virology and immunology 1.Laryngeal papillomas in children are generally caused by the same viruses that cause benign genital condylomas. These viruses are: a. Papillomaviruses, types 6 and 11 b. EBV c. Papillomaviruses, types 16 and 18 d. Polyomavirus JC 2.A 43-yea...

Virology and immunology 1.Laryngeal papillomas in children are generally caused by the same viruses that cause benign genital condylomas. These viruses are: a. Papillomaviruses, types 6 and 11 b. EBV c. Papillomaviruses, types 16 and 18 d. Polyomavirus JC 2.A 43-year-old man who is HIV-positive comes to the emergency department because of vision problems over the previous 2 days. Neurologic examination reveals problems with speech, memory, and coordination. CD4 cell count is 24cells/ml. He is admitted to the hospital, but his symptoms rapidly worsen and he dies 3 weeks after admission During his hospitalization, a 3D FLAIR MRI reveals hyperintense areas of demyelination. Which of the following is the most likely cause of death in this patient? e. JC virus f. Herpes simplex virus g. Varicella-Zoster virus h. Toxoplasma gondii i. Adenovirus 3.A 31-year-old male visits your office with complaints of fever and joint pain. Lab investigations of blood smear show atypical lymphocytes. On further investigation the infection is suspected to be caused by an enveloped virus having partially double-stranded circular DNA. An  enzyme packed in its virion has RNA-dependent DNA polymerase activity. This patient is most likely infected with: A) Cytomegalovirus B) Human immunodeficiency virus C) Epstein-Barr virus D) Hepatitis B virus E) Coxsackie virus 4.A 70-year-old man presents to his physician because of difficulty breathing, fever, and chills. His symptoms began 2 days ago and have been getting progressively worse. He states that he also has a constant headache, and intermittent nausea, vomiting, and diarrhea. His temperature is39ºC (102.2"F), blood pressure is 102/72 mm Hg, pulse is 72/min, respiratory rate is 22/min, and Sp02 is 96% on room air. The patient is treated with - oseltarnivir, and his symptoms resolve over the next 4 days. However, 2 days after the resolution of his symptoms the patient returns to the physician's office, this time with worsening dyspnea. Sp02 of 90% on room air, and a productive cough with mucopurulent sputum, A chest X-ray reveals bilateral lower lobe consolidation. The patient is admitted to the hospital and treated with intravenous antibiotics. Which of the following best describes the structure of the viral genome that most likely caused his initial illness? A) Enveloped, double-stranded DNA B) Non-enveloped, non-segmented, positive-sense, single-stranded RNA C) Enveloped, non-segmented, single-stranded, positive-sense RNA with a helical capsid D) Non-enveloped, segmented, double-stranded RNA  E) Enveloped, segmented, negative-sense, single- stranded RNA 5. A newborn boy is brought to the pediatrician for evaluation of an extensive skin rash. Questioning of the infant's mother reveals that early in her pregnancy, she had a fever and sore throat with generalized fatigue for a few days. Physical examination shows that this infant has microcephaly, hearing loss, and a petechial skin rash. Auscultation reveals normal heart and breath sounds. The abdominal examination reveals hepatosplenomegaly. S Which of the following is the most likely diagnosis? A) Congenitally acquired rubella B) Congenitally acquired HIV C) Congenitally acquired herpes simplex virus D) Congenitally acquired syphilis E) Congenitally acquired cytomegalovirus 6. A2-year-old boy is brought to his pediatrician by his mother, who states that he has had watery diarrhea and abdominal pain for 3 days. The boy has not received a complete set of vaccinations. His heart rate is 150/min and his blood pressure is 98/75 mm Hg. The exam shows symptoms of severe dehydration such as dry mucous membranes and increased capillary refill time. Which of the following best describes the pathogen most likely responsible for this patient's symptoms? A. Single-stranded, enveloped RNA virus with negative polarity B) Double stranded, enveloped, linear DNA virus C) Nonenveloped, double-stranded DNA virus D) Single-stranded, enveloped RNA virus with positive polarity  E) Double-stranded, nonenveloped, linear-segmented RNA virus 7. A 5-year-old boy is brought to the emergency department because of a 2-day history of fever (38.3ºC / 101º F), sore throat, hoarse voice, nasal congestion, and violent coughing (seal-like barking cough). The child's mother reports that his, cough has been worse at night and has failed to respond to home remedies. On auscultation, inspiratory stridor is heard. Between coughing spells, the child is noted to have intercostal retractions. What is the RNA genome structure of the virus that is most likely causing this patients illness? A) Single-stranded, negative sense, circular B) Single-stranded, positive sense, linear, non- segmented C) Double stranded, linear D) Single-stranded, negative-sense, linear, non- segmented E) Single-stranded, negative-sense, linear, segmented 8. Which of the following hepatitis viruses requires concurrent infection with virus to replicate in hepatocytes? A) Hepatitis delta virus B) Hepatitis B virus C) Hepatitis A virus D) Hepatitis E virus E) Hepatitis C virus 9. A 17-year-old girl who moved from rural India two years ago is accompanied to the doctor's office by her sister because of a 6-month history at severe frequent jerking  movements in the arms and legs. The sister also reports that, over the past year, the patient's memory has been worsening and that she has on several occasions gotten lost while walking home from school. Upon further questioning, the patient and her sister are unsure of their child hood vaccination status. Infection with which of the following agents is most likely responsible for this patient's presentation? A) Poliovirus B) Rubella virus C) Rabies virus D) JC virus E) Measles virus 10. A 48-year-old man is evaluated in the outpatient clinic because of a----- and pedal edema of several weeks of duration. He has a history of intravenous drug abuse beginning at age 14 years and ending 10 years ago. He denies alcohol consumption. ! Temperature is 37°C (98. 6 "F), pulse is8&min, respiratory rate is 19/min; blood pressure is 130/80 mm Hg, and BMI is 22. On physical examination there is generalized jaundice, spider angiomas on the upper chest and abdomen, red palms, dilated and visible epigastric veins, and swollen breast tissue. Palpation over the abdomen discloses a hard irregular liver. Abdominal ultrasonography shows disrupted architecture of the liver. Viral nucleic acid is isolated from the cytoplasm, but not the nucleus, of infected cells. To which of the following viral families does the likely causative agent belong? A) Parvovirus B) Picornavirus drugs C) Flavivirus D) Hepadnavirus E) Adenovirus 11. A 20 y/o man who for many years had received daily injections of GH, prepared from human pituitary glands, develops ataxia, slurred speech, and dementia. On autopsy the brain shows widespread neuronal degeneration, a spongy appearance due to many vacuoles between the cells, no inflammation, and no evidence of virus particles. The most likely diagnosis is: a. Herpes encephalitis b. Rabies c. CJD d. Subacute sclerotizing panencephalitis 12. A 41 y/o HIV-infected male who had refused antiretroviral therapy is diagnosed with Pneumocystis juroveci infection. This patient: a. Probably has declining levels of plasma viremia b. Probably has a CD4 T-cell count below 200 cells/ microliter c. Is unlikely to develop dementia at this stage d. Is at elevated risk for lung cancer 13. A 32 y/o male who visits your office with complaints of general weakness and fatigue. He has high levels of ALT and AST and is found to have high titers of IgG directed against hep C enveloped protein. These antibodies do not confer effective immunity against the infection because: a. Envelope proteins have low immunogenicity b. The antibodies do not have neutralizing properties c. Envelope proteins vary their antigenic structure d. Envelope proteins are lost after recurrent replications 14. What structural organization allows immune cells access to all parts of the body? A) The dual blood and lymphatic, circulation B) Abundance of primary lymphoid tissue C) Ability of Toxic molecules produced by immune system to access all areas of the body D) Phagocytes that are smaller some pathogen E) MALT 15. A 34-year-old man presents to his primary care physician for a follow up evaluation. He has a history of genital herpes and has not had a recurrence in 1 year He engages in protected sexual relations with his partner. Which of the following statements is correct regarding this microorganism? A) Contains both DNA and RNA B) Surrounded by a lipid bilayer C) Contains DNA as a genetic material D) Has a discrete cellular structure E) Obligate extracellular parasite 16. Which of the following human diseases has not been associated with adenoviruses? A) Keratoconjunctivitis B) Common colds C) Acute respiratory diseases D) Cancer 17. A 22-year-old woman who is a college student comes  to the emergency department because of a 1-day history of dark urine and a 1-week history of nausea, vomiting. abdominal pain, and malaise. She went to Cancun for spring break. 1 month ago, but she has no other history of travel. She has three sexual partners with whom she used condoms regularly. She drinks two to three beers per day, but sometimes she drinks more on the weekends. She does not use intravenous drugs. Her temperature today 38º C (100.6* F), blood pressure is 126/78 mmHg, pulse is92/min, and respiratory rate is 18/mn On physical examination, scleral icterus and tenderness in the right upper quadrant of the abdomen are noted. Which of the following is the most likely diagnosis? A) Staphylococcus aureus food poisoning B) Viral gastroenteritis C) Cholera D) Acute hepatitis A E) Acute Hepatitis B 7518. A 33-year old homeless man is emergency department by a friend. The brought to the friend reports that although the patient is HIV positive, he has never seen him taking any medication. The patient's initial complaints centered on generalized weakness and vision difficulties, which started several weeks ago. Overtime, the patient lost his peripheral vision and became unable to talk or walk. The man appears disheveled and is not oriented to person, place, or time. A lumbar puncture is performed, and cerebrospinal fund analysis results came normal. His CD4 count is 35/mm3. What is the most likely diagnosis? A) Cryptococcal meningitis B) Progressive multifocal leukoencephalopathy C) Acute disseminated encephalomyelitis D) Guillainé-Barre syndrome E) Herpes simplex meningitis 19. 43-year-old man comes to the physician because of flu-like symptoms, headache, photophobia, and pain in his knees and lower back 3 days after returning from a rafting trip to South America. He says that his appetite has been very poor: He has been nauseated and las vomited dark blood on Iwo occasions I he patient reports that he dd not have any new vaccinations prior to the trip and, although he was given prophylaxis for mosquito borne illness, he did not take the medication consistently. While traveling he was bitten by mosquitoes. He did not eat shellfish or rave vegetables and only consumed bottled water. He denies any sexual intercourse or drug use during this trip. On examination today, his temperature is 39°C (102.2*F) and his pulse is 40/min. His face is flushed and his, conjunctivae are red. The patient's abdomen is tender in the epigastrium, and his liver edge is palpable 3 cm below the costal margin. A complete blood count and liver function tests show WBC count: 2000/mm 3 Neutrophils: 40% AST. 900 U/L ALT 350 U/L Which of the following virus is responsible for this patient's condition? A) Picornavirus B) Hepevirus C) Flavivirus /10 conta dat D) Hepadnavirus E) Togavirus 20. Hepatitis delta virus is unique in that: A) Infectivity requires an envelope protein provided by a helper virus. B) its mRNA is transcribed by a transcriptase supplied by a helper virus C) encodes a protein delta antigen (HDAg) that replaces helper virus glycoproteins in the envelopes of helper virus particles, D) it has an RNA genome that is replicated by a replicase supplied by a coinfecting helper virus E) the virion contains a reverse transcriptase provided by a helper virus. 21. A 15-year-old boy from Africa presents with a swelling on his jaw, recurrent episodes of epistaxis, weight loss, and generalized fatigue. Physical examination of the neck reveals multiple firm, non-tender lymph nodes approximately 1.5 cm in size. Nasopharyngoscopy reveals a mass arising in the nasopharynx. The mass is biopsied. Under light microscopy. the cells are arranged in a syncytial pattern with vesiculated nuclei and prominent nucleoli Immunohistochemistry is consistent with non- keratinizing nasopharyngeal carcinoma, undifferentiated. What is the genomic structure of the most likely causative virus? A) Double-stranded linear RNA B) Double-stranded circular DNA C) Double-stranded linear DNA D) Single-stranded linear RNA E) Single-stranded linear DNA 22. A 21-year-old man with AIDS develops a chronic herpes simplex virus (HSV) infection of the lip. He is treated with acyclovir and improves, but he relapses after 4 weeks of acyclovir treatment. The HSV cultured from the lesion after the relapse is resistant to acyclovir. Resistance has most likely developed because of an alteration in which of the following viral proteins? A) DNA-dependent DNA polymerase B) Serine protease C) Nucleocapsid D) Thymidine kinase E) Glycoprotein B 23. A4-vear old boy is brought to the clinic by his mother because of a generalized rash. His mother states the rash started on his face and has spread to the trunk and extremities. He had a fever 3 days before the onset of the rash The patient emigrated from India a few days ago and has not received any childhood vaccination. He does not have any other medical conditions and does not take any medications He has no family history of any medical problems. Temperature is 37 2ºC (38 9°F) Physical examination shows a f—(Fine?) generalized maculopapular rash over the patient's trunk and face and tender postauricular lymphadenopathy bilaterally as shown. He also has tenderness, in his joints. Which of the following is the most likely diagnosis? A) Parvovirus B19 B) Rubella virus, C) Human herpesvirus 6 (HIH-V-6) D) Measles E) Coxsackie A virus 24. A.6-month-old girl with difficulty breathing is brought to the emergency department. Nasal flaring and suprasternal retractions are noted on arrival. The parents state that the child has been getting progressively sicker alter developing a cough and rhinorrhea 3 days earlier. She has no past medical history. Vital signs are: temperature 37.43ºC (99 AF), blood pressure 80/40 mm Ha, pulse: 120 bpm, respiratory rate 38/min, and Sp02 90% on room air. Auscultation of the lungs reveals wheezes and rhonchi bilaterally. Intubation was required alter nasal suctioning, and supplemental oxygen did not improve the patient's Sp02t. Which of the following describes the most likely etiologic agent of the girl’s condition? A) Enveloped RNA virus with a single-stranded, negative- sense, and segmented genome B) Non-enveloped RNA virus with a double-stranded and segmented genome C) Enveloped RNA virus with a single-stranded, positive- sense, and non-segmented genome D) Enveloped RNA virus with a single- stranded, negative-sense, and non-segmented genome E) Non-enveloped RNA virus with a single stranded, positive-sense, and non- segmented genome 25. A 27-year-old woman from South Korea presents to her primary care doctor for her first visit. She is in good health and denies any current symptoms. However, she notes that several months ago she had severe abdominal pain that has since completely resolved. The pain was intermittent and lasted for several months and was not associated with nausea or vomiting. Her physician orders a hepatitis panel, given this patient's history of abdominal pain. Results of serologic testing are: HBeAg-negative HBsAg-negative Anti-HBs-positive Anti-HEc-positive Which of the following conclusions is most correct? A) The patient has been exposed to hepatitis B virus and is now chronically infected B) The patient was vaccinated against hepatitis B and has immunity, C) The patient has been exposed to hepatitis B virus and is in the window period. D) The patient has been exposed to hepatitis B virus and is in the acute disease phase. Has recovered? Vbnm,……./? 26. A 22-year-old female IV drug user is seen in an emergency room when she suffers from fever chills, headache, and abdominal pain. Her skin and eyes have a yellow hue. The physician suspects hepatitis and conducts several blood and serological tests, which provide the following results: Serum ALT 2560 U/L Serum; AST 2160 U/L HBsAg positive; HBcIgM positive; HBeAg positive; HAV IgM negative; HCVAb negative; HCV RNA negative Given these results, which of the following represents the most likely diagnosis? A) Acute hepatitis B infection B) Acute hepatitis C infection C) Acute hepatitis A infection D) Chronic hepatitis B infection E) Chronic hepatitis C infection 27. A21-year-old woman comes to the clinic because of a painful ulcer on her lover lip for the past 3 days. On further questioning, she states that she has experienced identical symptoms in the past with painful vesicles organizing into ulcers over a 1–2-week period The pathogen affecting this patient is also known to cause which at the following manifestations? A) Shingles B) Mononucleosis C) Impetigo D) Oral thrush E) Keratoconjunctivitis 28. Which of the following is a factor that predicts the progression of an HIV-infected individual to AIDS? A) HIV viral load, viral phenotype, and host genetic variability, CD count. B) CD4 count C) HIV viral load D) Host genetic variability E) Viral phenotype  29. A 15-month infant is brough to you by her mother who noticed truncal rashes on her baby 2 days ago and a fever which culminated in an episode of febrile convulsion yesterday. The child is playing normally now. You notice macular rashes, pale, reddish spots with ---- heads mainly on her trunk and on her thighs and lower neck. Which of the following viruses is closely related to this viral exanthema? A) Parvovirus B19 B) HHV6 C) Rubella virus D) Herpes virus 30. An unconscious 40-year-old man is brought to the emergency department by his, wife She states that her husband complained of severe muscle aches, fever, chills, and headache of sudden onset 4 days ago, Last night, he A developed a dry cough. She also notes that he recently went to clean out their cabin which was infested with rodents in rural Colorado. On evaluation today, blood pressure is 130/90 mm Ha, pulse is 125/min, respiratory rate is28/min, and temperature is40°C (104*F), Physical examination reveals inspiratory crackles in both lungs, A chest x-ray shows bilateral interstitial pulmonary edema. To which infectious agent was the patient most likely exposed? A) Flavivirus B) Plasmodium falciparum C) Hantavirus D) Alphavirus E) West Nile virus 31. A 32 y/o pregnant woman develops an illness after ingesting river water on a trip abroad. Her symptoms include jaundice, anorexia, fever, severe abdominal pain, nausea, vomiting, and malaise. Many other people on the trip experienced similar, but less severe symptoms. She is admitted to the hospital and spends 2 weeks in the ICU before her condition is stabilized. Lab tests at admission show an ALT level of 600 U/L and an AST level of 420 U/L. Which of the following virus types did this woman most likely contract? A) Nonenveloped, single stranded RNA virus B) Enveloped RNA virus C) Enveloped, linear DNA virus D) Small defective circular RNA virus E) Enveloped, circular DNA virus pregnancy 32. A 27 y/o primigravid woman at 26 weeks’ gestation comes to her physician 5 weeks after returning from a trip to her grandfather’s home in rural India. She is jaundiced and complains of nausea, vomiting, fever, and abdominal pain. She denies any new sexual contacts and has never used recreational drugs. She has no significant medical history. Hepatomegaly is noted on examination. Her lab results are as follows. Aspartate aminotransferase 1,010 U/L. ALT 2,584 U/L. Total bilirubin 4.6 mg/dL. Direct bilirubin 3 mg/dL. What is the genomic structure of the virus that is most likely the cause of this patient’s presentation? A) Double-stranded linear DNA B) Single-stranded circular DNA C) Single-stranded linear RNA D) Double-stranded linear RNA E) Single-stranded linear DNA F) Partially double-stranded circular DNA 33. A37-year-old man with a history of HIV infection is brought to the emergency department by his neighbor because of unusual behavior and disorientation. The patient also has a history of noncompliance with his HIV medication. On physical examination, he exhibits weakness of the right upper and lower limbs, disorganized meaningless speech, and ataxia. He is admitted to the hospital and experiences multiple focal seizures during his stay. Urine toxicology is negative, but blood tests reveal a second infection. MRI reveals high signal intensity in the temporal lobes and hippocampus His CD4 count is 78 cells/mm. During its latency period, which of the following components of the superinfecting virus can be detected in infected neurons? A) Viral DNA polymerase B) Double stranded DNA C) Single-stranded DNA D) Viral reverse transcriptase E) Viral nucleocapsids 34. A 22-year-old man visits his college medical center complaining of flu-like symptoms that have been present for about 1 week. He reports low grade fevers, night sweats, a painful sore throat, headaches, and increasing fatigue. He used to exercise 5 days a week but is no longer able to do so because of “lack of energy”. Vital signs reveal a temperature of 100.8ºF (38.2ºC), blood pressure of 114/62 mm Hg, pulse of 95, and respiratory rate of 12. His heart has a regular rate and rhythm with no audible murmurs. His lungs are clear to auscultation bilaterally. The rest of the examination reveals erythematous tonsils  without exudates, enlarged cervical lymph nodes, and a palpable spleen tp. What is the structure of the virus that has most likely infected this patient? A) Linear double-stranded DNA virus with an envelope B) Linear single stranded RNA virus Without an envelope C) Linear double-stranded DNA virus without an envelope D) Linear double-stranded RNA virus without an envelope E) Segmented single-stranded RNA virus with an envelope 35. A previously healthy 5-year-old boy is brought to the pediatrician with a 3-day history of sore throat, conjunctivitis, rhinitis, and cough. His mother explains that more than 10 A children in his class at school have similar symptoms, particularly conjunctivitis. His temperature is 100. 4ºF (38ºC), pulse is 108/min, and blood pressure is 110/30 min Hg No cultures are ordered, and the mother is assured that her son's illness will go away on its own. One week later, the mother reports that her son is healthy and back at school. Which of the following is the most likely causative agent in this child's illness? A) Adenovirus B) Cytomegalovirus C) Bordetella pertussis D) Coxsackie A virus E) Rhinovirus 36. Which of the following patients is at increased risk to acquire hep B infection? A) 34 y/o man with DM type II B) 65 y/o man with prostate cancer C) 44 y/o man with renal failure who receives a clotting factor transcription D) 55 y/o man with pancreatic cancer E) 22 y/o man heterosexual man 37. A 28-year-old man who is HIV positive comes to the physician because of worsening Eyesight. He states that his loss of vision is associated “floaters” in his right eye. The symptoms progressed rapidly, and now he can barely see out of his right eye, ant his left eye has become affected also. His last CD4 count was 43 cellus/mm3. Fundoscopic examination reveals cotton-wool exudates, necrotizing retinitis, and pervivascular hemorrhages. Which virus can cause this patient's condition? A) HSV.1 B) VZV C) Adenovirus D) CMV 38. Somebody is taken to her primary care physician by her mother due to a cold that has been ongoing for 3 weeks. The patient’s medical history is unremarkable and her mother is her primary caregiver. On physical examination, she appears to be in pain and has nuchal rigidity. Temperature is 38.4º C (101 2° F), blood pressure is 110/80 mm Hg, and respiratory rate is 16 breaths/min. Culture of her cerebrospinal fluid shows: Opening pressure: 18 cm H20 (normal: 10-20 cm H20) Protein: 50 mg/dt. (normal