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NBME Micro > Microbiology: Virology > Flashcards

Microbiology: Virology Flashcards

1
Q

What 3 DNA viruses are not linear?

A

Hepadnavirus (circular, incomplete), papillomavirus (circular, supercoiled), and polyomavirus (circular, supercoiled)

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2
Q

What properties of the PrPsc prion protein enable its infectivity?

A

Transmissible via infected CNS tissue (iatrogenic Creutzfeldt-Jakob disease [CJD]) or food (variant CJD); resistant to degradation by proteases & standard sterilization procedures

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3
Q

In which viral family do viruses have single-stranded circular RNA that is both positive sense and negative sense (ambisense)?

A

Arenaviruses

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4
Q

What hepatitis virus can initially present like serum sickness?

A

Hepatitis B

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5
Q

Where does the herpes simplex virus-2 lie latent?

A

Sacral ganglia

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6
Q

What roles do hemagglutinin and neuraminidase play with influenza infection?

A

Hemagglutinin promotes viral entry by binding to sialic acid; neuraminidase promotes virion release

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7
Q

What is the RNA structure of the deltavirus?

A

Enveloped, single-stranded, negative-sense, circular RNA with an uncertain capsid

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8
Q

Which RNA virus family does the often fatal Marburg hemorrhagic fever belong to?

A

Filoviruses

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9
Q

Name the family of each of the hepatitis viruses (HAV, HBV, HCV, HDV, HEV).

A

HAV - RNA picornavirus; HBV - DNA hepadnavirus; HCV - RNA flavivirus; HDV - RNA deltavirus; HEV - RNA hepevirus

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10
Q

What viral infections are associated with intranuclear eosinophilic Cowdry A inclusions?

A

Herpes simplex virus-1 (HSV-1), herpes simplex virus-2 (HSV-2), varicella-zoster virus (VZV)

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11
Q

What does a heterozygous CCR5 gene mutation indicate for the disease course in a patient with HIV?

A

Slower disease course

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12
Q

Name the 7 positive-stranded RNA viruses.

A

I go to a retro (retrovirus) toga (togavirus) party and drink flavored (flavivirus) Corona (coronavirus) and eat hippie (hepevirus) California (calicivirus) pickles (picornavirus)

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13
Q

Name the 4 RNA viruses that have segmented genomes.

A

Reovirus (10-12 segments), orthomyxovirus (8 segments), arenavirus (2 segments), and bunyavirus (3 segments)

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14
Q

What is the only positive-sense RNA virus with a helical capsid?

A

Coronaviruses

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15
Q

What phenomenon might be seen in a patient with severe croup?

A

Pulsus paradoxus caused by upper airway obstruction

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16
Q

Which RNA virus family does Ebola hemorrhagic fever belong to?

A

Filoviruses

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17
Q

What is the test of choice for skin and genital findings suggestive of herpes simplex virus?

A

Viral culture

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18
Q

What condition in humans is caused by picornaviruses (except rhinovirus and hepatitis A)?

A

Aseptic meningitis

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19
Q

Infections with which organisms are possible when the CD4+ count is <200 cells/mm3?

A

JC virus reactivation, Pneumocystis jirovecii, HIV infection leading to dementia, and Histoplasma capsulatum

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20
Q

How can hepatitis C be acquired?

A

Intravenous drug use or blood transfusions

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21
Q

What mediates the granular eosinophilic “ground glass” appearance found on a liver biopsy specimen of hepatitis B?

A

Cytotoxic T-cell damage causes the granular eosinophilic appearance

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22
Q

What is the DNA structure of the hepatitis B virus?

A

Enveloped, partially double-stranded, circular DNA

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23
Q

Palivizumab is used to prevent respiratory syncytial virus (RSV) in what age group?

A

Premature infants (Palivizumab for Paramyxovirus [RSV] Prophylaxis in Preemies)

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24
Q

What vaccine has made mumps uncommon?

A

MMR (measles, mumps, rubella)

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25
Q

What is the function of the 2 envelope proteins on the surface of HIV

A

Gp120 helps HIV adhere to CD4+ T cells; gp41 facilitates HIV fusion/entry

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26
Q

What is the viral receptor for rabies?

A

Nicotinic acetylcholine receptor

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27
Q

What RNA family contains the hepatitis E virus?

A

Hepevirus

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28
Q

What is the definition of viral genetic recombination?

A

Gene exchange between 2 chromosomes via crossing over that occurs within regions of significant base sequence homology

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29
Q

Which naked (nonenveloped) viruses are DNA viruses?

A

Papillomavirus, Adenovirus, Parvovirus, Polyomavirus (PAPP)

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30
Q

In what parts of the world is hepatitis E infection most common?

A

Asia, Africa, and the Middle East

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31
Q

Which populations are at particularly high risk for rotavirus?

A

Infants and young children, especially in day care centers and kindergartens

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32
Q

Name the 6 negative-stranded viral families.

A

Arenaviruses, Bunyaviruses, Paramyxoviruses, Orthomyxoviruses, Filoviruses, Rhabdoviruses (Always Bring Polymerase Or Fail Replication)

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33
Q

Which hepatitis serologic markers are found during the window period?

A

IgM anti-HBc and anti-HBe

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34
Q

Two viruses coinfect a cell. Virus A becomes partially or completely coated with virus B proteins, but progeny have type A genome and coat. What is this called?

A

Phenotypic mixing

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35
Q

What is seen on biopsy of tissues infected with cytomegalovirus?

A

Cells with intranuclear inclusion bodies (owl’s eye appearance)

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36
Q

How does HIV integrate its genome into the host DNA?

A

Reverse transcriptase converts HIV viral RNA to double-stranded DNA, which then integrates into host DNA

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37
Q

Which lobe of the brain is most commonly affected in herpes encephalitis?

A

Temporal lobe

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38
Q

What diseases are caused by paramyxoviruses?

A

Parainfluenza, mumps, measles, RSV, and human metapneumovirus (which causes bronchiolitis/pneumonia in infants and children)

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39
Q

Name 2 coreceptors HIV can use to enter immune cells?

A

CXCR4 (on T-cells for late infection) and CCR5 (on macrophages for early infection)

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40
Q

Name 6 viral families that are single-stranded, positive-sense, linear RNA viruses with icosahedral capsids.

A

Picornavirus, hepevirus, calicivirus, flavivirus, togavirus, and retrovirus (HTLV only)

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41
Q

By way of what surface marker does Epstein-Barr virus (human herpes virus-4) infect B cells?

A

CD21 (“must be 21 to drink Beer in a Barr”)

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42
Q

What is the purpose of neuraminidase on the parainfluenza viral membrane?

A

Promotes progeny virion release

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43
Q

During which phase of HIV infection does the CD4+ cell count drop most sharply?

A

Acute phase (first 1–2 months)

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44
Q

What 2 animals act as reservoirs for the yellow fever virus?

A

Monkeys and humans

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45
Q

Viruses A and B infect a cell. A mutates and becomes nonfunctional; B makes a protein that functions for both A and B. What is this called?

A

Complementation

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46
Q

What biopsy finding is consistent with Kaposi sarcoma?

A

Lymphocytic inflammation (caused by human herpesvirus-8)

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47
Q

What presentation might cytomegalovirus infection have in the population with HIV/AIDS?

A

Colitis, encephalitis, pneumonitis, esophagitis, and retinitis

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48
Q

Why are purified nucleic acids of certain dsDNA and positive-strand ssRNA viruses infectious?

A

The dsDNA and ssRNA can utilize host cell machinery (eg, polymerases)

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49
Q

What stage of hepatitis B infection does positive anti-HBe and anti-HBc IgM indicate?

A

Window period

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50
Q

Which human papillomavirus (HPV) serotypes are associated with warts?

A

1, 2, 6, and 11

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51
Q

What are 3 general mechanisms for Zika virus transmission?

A

Transmitted by Aedes mosquito bites (most common), but sexual and vertical transmission are possible

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52
Q

Parvovirus B19 uses what receptor to attach to red blood cells?

A

Parvovirus B19 uses the P antigen

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53
Q

According to the CDC guidelines, what medical conditions are contraindications for rotavirus vaccination in infants?

A

History of intussusception or Severe Combined Immunodeficiency (SCID)

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54
Q

How is Ebola transmitted? I

A

Direct contact with body fluids, fomites (including corpses), infected bats/primates; nosocomial infection is common

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55
Q

Name 4 medically significant conditions caused by bunyaviruses.

A

California encephalitis, Crimean-Congo hemorrhagic fever, sandfly/Rift Valley fevers, hantavirus infection (hemorrhagic fever, pneumonia)

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56
Q

What is the test of choice for the diagnosis of Zika virus?

A

Reverse transcription polymerase chain reaction (RT-PCR) or serology

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57
Q

What CD4+ count is associated with esophagitis from a Candida albicans infection in patients with HIV/AIDS?

A

<100 cells/mm3

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58
Q

Which DNA virus is single stranded?

A

Parvovirus, the rest of the DNA viruses are all double stranded

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59
Q

What are the most common endocrine manifestations of hepatitis C?

A

↑ risk of diabetes mellitus and autoimmune hypothyroidism

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60
Q

In what central nervous system tissue are negri bodies commonly found in rabies infection?

A

Cerebellum (Purkinje cells) and/or hippocampus

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61
Q

What is the RNA structure of the filovirus?

A

Enveloped, single-stranded, negative sense, linear with a helical capsid

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62
Q

From what cellular structure do enveloped viruses generally get their envelopes?

A

From the plasma membrane as they leave the cell

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63
Q

How do the Epstein-Barr virus (EBV) and strep throat differ in their cervical lymphadenopathy locations?

A

EBV is more strongly associated with posterior cervical lymphadenopathy; strep throat involves anterior cervical lymphadenopathy

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64
Q

What is the prognosis for hepatitis B in adults and neonates?

A

Adults, mostly a full resolution; neonates, a worse prognosis

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65
Q

What virus causes global infantile gastroenteritis?

A

Rotavirus (ROTAvirus = Right Out The Anus)

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66
Q

What molecular characteristic allows the hepatitis C virus to outsmart host antibodies?

A

Lack of 3′-5′ exonuclease activity leads to antigenic variation of HCV envelope proteins and new viral mutant strains

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67
Q

What are the 2 most common renal manifestations of hepatitis B?

A

Membranous glomerulonephritis > membranoproliferative glomerulonephritis

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68
Q

How are the HIV envelope proteins formed?

A

The env gene encodes gp160 precursor that is cleaved into gp120 and gp41

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69
Q

What is the smallest DNA virus?

A

Parvovirus

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70
Q

What is the RNA structure of the picornavirus?

A

Non-enveloped, single-stranded, positive-sense, linear RNA with an icosahedral capsid

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71
Q

What are initial symptoms of Ebola?

A

Abrupt onset of flu-like symptoms, high fever, diarrhea/vomiting, myalgia

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72
Q

Name 2 viruses found in the reovirus family.

A

Rotavirus and coltivirus

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73
Q

What virus may be responsible for non-Hodgkin lymphoma development in patients with HIV/AIDS?

A

Epstein-Barr virus

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74
Q

What are symptoms of mumps?

A

Parotitis, Orchitis, aseptic Meningitis, Pancreatitis (mumps makes your parotid glands and testes as big as POM-Poms)

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75
Q

What type of capsid shape do most negative-sense RNA viruses have and with what exception?

A

Helical; delta viruses have uncertain capsid symmetry

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76
Q

How can hepatitis E be acquired?

A

Via the fecal-oral route, especially from waterborne sources

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77
Q

What is the RNA structure of the arenavirus?

A

Enveloped, single-stranded, positive- and negative-sense, circular (in 2 segments) RNA with a helical capsid

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78
Q

How is the chicken pox transmitted?

A

Via respiratory secretions or contact with fluid from vesicles

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79
Q

Describe the structure of the genome of most DNA viruses.

A

Most of them have a double stranded, linear genome

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80
Q

What is the function of hemagglutinin on the parainfluenza viral membrane?

A

Promotes viral entry by binding to sialic acid

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81
Q

What is the ploidy of the HIV genome?

A

Diploid RNA

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82
Q

What virus family does parainfluenza (causes croup) belong to?

A

Paramyxoviruses

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83
Q

What characteristic liver biopsy findings are seen in hepatitis C?

A

Lymphoid aggregates, focal macrovesicular steatosis

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84
Q

What is the disease that can occur with rapid-onset dementia and ataxia after eating beef from infected cattle?

A

Bovine spongiform encephalopathy (BSE), also known as “mad cow disease”

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85
Q

What is the RNA structure of the calicivirus?

A

Non-enveloped, single-stranded, positive-sense, linear RNA with an icosahedral capsid

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86
Q

Which HIV proteins are located in the envelope, matrix, and capsid, respectively?

A

Envelope: gp120 and gp41; matrix: p17; capsid: p24

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87
Q

Name the viral family that is made up of double-stranded RNA viruses with double icosahedral capsids.

A

Reoviruses

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88
Q

How does transmission for herpes simplex virus- (HSV) 1 and 2 differ?

A

HSV-1 is spread in respiratory secretions and saliva; HSV-2 is spread by sexual contact and perinatally

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89
Q

What is the route of transmission for hepatitis A?

A

Via fecal-oral (through ingestion of contaminated shellfish, exposure during travel, or in dayca

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90
Q

If the receptor intracellular adhesion molecule 1 (ICAM-1) is blocked, what virus will have difficulty infecting the cells?

A

Rhinovirus (binds to ICAM-1); “take a picture of the rhino with a camera”

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91
Q

What is the definition of moderately immunocompromised in HIV?

A

CD4+ count: 200-400 cells/mm3

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92
Q

Which of the hepatitis-causing viruses is the only DNA virus?

A

Hepatitis B virus (hepadnavirus)

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93
Q

What causes pandemics versus epidemics?

A

Genetic/antigenic shift causes pandemics; genetic/antigenic drift causes epidemics (sudden shift is more deadly than gradual drift)

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94
Q

Name some of the conditions caused by herpes simplex virus-1.

A

Keratoconjunctivitis, herpes labialis, herpetic whitlow, encephalitis, erythema multiforme, esophagitis, gingivostomatitis

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95
Q

Which 2 picornaviruses commonly cause aseptic meningitis?

A

Echovirus and coxsackievirus

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96
Q

Which DNA virus replicates outside of the nucleus?

A

Poxvirus; it has a DNA-dependent RNA polymerase and can replicate without nuclear enzymes

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97
Q

What is the RNA structure of the coronavirus?

A

Enveloped, single-stranded, positive-sense, linear RNA with a helical capsid

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98
Q

What infection in a patient who is HIV ⊕ with a CD4+ count <100 cells/mm3 presents with a TB-like disease and lymphadenitis?

A

Mycobacterium avium-intracellulare, Mycobacterium avium complex infection

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99
Q

What serologic markers would you expect in a patient immunized against Hepatitis B?

A

⊕ Anti-HBs (all other hepatitis B markers negative)

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100
Q

How is hepatitis B acquired?

A

Methods of acquiring HBV: Parenteral (Blood), sexual (Baby-making), perinatal (Birthing)

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101
Q

What disease presents with esophagitis and linear ulcerations on esophagogastroduodenoscopy (EGD) in the population with HIV/AIDS with a CD4+ count <100 cells/mm3?

A

Cytomegalovirus esophagitis

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102
Q

What dermatological conditions can be seen in patients with hepatitis C?

A

Sporadic porphyria cutanea tarda and lichen planus

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103
Q

What CD4+ count is associated with oral thrush from a Candida albicans infection in patients with HIV?

A

<500 cells/mm3

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104
Q

Where does herpes simplex virus-1 lie dormant?

A

Trigeminal ganglia

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105
Q

What is the RNA structure of the orthomyxovirus?

A

Enveloped, single-stranded, negative-sense, linear (in 8 segments) RNA with a helical capsid

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106
Q

A patient recently returned from Brazil with conjunctivitis, low-grade fever, and an itchy rash. You suspect a flavivirus to be the cause. What is the most appropriate treatment?

A

Supportive care (diagnosis: Zika virus infection)

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107
Q

Why can hepatitis D (HDV) infection only occur in conjunction with hepatitis B (HBV) infection?

A

HDV is a defective virus so it relies on the HBV HBsAg coat for entry into hepatocytes

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108
Q

What 5 RNA viruses are picornaviruses?

A

Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, Hepatitis A virus (PERCH on a “peak” [picornavirus])

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109
Q

Which 2 RNA viruses do not replicate in the cytoplasm?

A

Retrovirus and influenza virus (retroflu is outta cyt [sight])

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110
Q

Which 3 DNA virus families contain circular DNA?

A

Papillomaviruses, polyomaviruses, and hepadnaviruses; all other viruses have linear DNA

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111
Q

What rodent-borne bunyavirus causes a hemorrhagic pulmonary syndrome?

A

Hantavirus

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112
Q

How can cytomegalovirus present in adults?

A

Mononucleosis in immunocompetent patients; retinitis, esophagitis, and infection in immunocompromised patients (pneumonia in transplant patients)

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113
Q

Rhinovirus has how many serotypes?

A

> 100 serologic types of rhinovirus

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114
Q

What gene mutation can cause immunity to HIV?

A

Homozygous CCR5 mutation (prevents HIV binding on macrophages)

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115
Q

What virus family does rhinovirus belong to?

A

Picornavirus

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116
Q

What is the DNA structure of hepadnaviruses?

A

Enveloped, partially double-stranded, circular DNA

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117
Q

What findings might be seen on fundoscopic exam in a patient with vision loss due to cytomegalovirus retinitis?

A

Hemorrhage and cotton-wool exudates

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118
Q

Other than animal bites, by what method of transmission can rabies also occur?

A

Aerosol transmission (in bat caves)

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119
Q

Which naked (nonenveloped) viruses are RNA viruses?

A

Calicivirus, Picornavirus, Reovirus (CPR), and hepevirus

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120
Q

What is the DNA structure of polyomaviruses?

A

Non-enveloped, double-stranded, circular DNA

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121
Q

What serological marker is best to detect acute hepatitis A?

A

Immunoglobulin M hepatitis A virus antibody (anti-HAV IgM)

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122
Q

What test can be performed in the setting of an inconclusive differentiation assay for HIV?

A

HIV-1 nucleic acid test (NAT)

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123
Q

Which of the 2 viruses that can lead to roseola is a less common cause of the disease?

A

Human herpes virus-7 (HHV-7) is a less common cause than human herpes virus-6 (HHV-6)

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124
Q

What is the DNA structure of parvovirus?

A

Non-enveloped, single-stranded, linear DNA (this is the smallest of the DNA viruses)

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125
Q

Other than the vasculature, what other anatomic locations can Kaposi sarcoma affect?

A

Gastrointestinal tract and lungs

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126
Q

Which serologic marker indicates prior infection (or vaccination) and protects against reinfection with hepatitis A?

A

Immunoglobulin G anti-hepatitis A virus antibody (anti-HAV IgG)

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127
Q

What test can be done to confirm the diagnosis of HIV if the HIV-1/2 Ag/Ab immunoassay is positive?

A

HIV-1/2 antibody differentiation immunoassay (which determines whether it is HIV-1 or HIV-2 infection)

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128
Q

Which hepatitis types can be transmitted by blood?

A

Hepatitis B, C, and D

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129
Q

What virus family does Ebola belong to?

A

Filovirus

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130
Q

By what mechanism does rotavirus cause gastroenteritis?

A

Rotavirus causes destruction of the intestinal villi, thus impairing Na+ absorption and leading to K+ wasting

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131
Q

Two segmented viruses undergo reassortment and produce a new, highly virulent strain. What is this process called?

A

Antigenic shift

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132
Q

Which calicivirus commonly causes viral gastroenteritis?

A

Norovirus

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133
Q

What stage of hepatitis B infection does positive HBsAg, HBeAg, and anti-HBc IgM indicate?

A

Acute stage of infection

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134
Q

Which disease caused by a poxvirus has been eradicated through the use of a live attenuated vaccine?

A

Smallpox

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135
Q

What is the RNA structure of the flavivirus?

A

Enveloped, single-stranded, positive-sense, linear RNA with an icosahedral capsid

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136
Q

Which organ transplant does the BK virus commonly target?

A

Kidneys; BK virus = Bad Kidney virus

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137
Q

What is the DNA structure of herpesviruses?

A

Enveloped, double-stranded, linear DNA

138
Q

What is the incubation period for Ebola?

A

Up to 21 days

139
Q

A man has a common cold because of a single-stranded, linear RNA virus that has an envelope. Name other viruses in the same family.

A

SARS and MERS; the patient’s cold is caused by a coronavirus

140
Q

What is the RNA structure of the hepatitis D virus (HDV)?

A

Single-stranded, negative-sense, circular RNA

141
Q

What is the typical presentation of rubella (German measles) infection?

A

Fever; postauricular lymphadenopathy; and a fine, maculopapular rash on the face and trunk, usually lasting for 3 days (hence the term “3-day measles”)

142
Q

Which viral family is responsible for smallpox, cowpox, and molluscum contagiosum?

A

Poxvirus

143
Q

What herpesvirus can cause shingles, encephalitis, and pneumonia?

A

Varicella-zoster virus (HHV-3)

144
Q

What is the name of the disease associated with “slapped cheeks” in children with parvovirus?

A

Erythema infectiosum or fifth disease

145
Q

What is the DNA structure of papillomaviruses?

A

Non-enveloped, double-stranded, circular DNA

146
Q

What viral family has the largest DNA virus?

A

Poxvirus

147
Q

What is the RNA structure of the paramyxovirus?

A

Enveloped, single-stranded, negative-sense, linear (nonsegmented) RNA with a helical capsid

148
Q

Infections with which organisms are possible when the CD4+ count is <100 cells/mm3?

A

Aspergillus fumigatus, Bartonella, Cryptococcus neoformans, Candida albicans, Cryptosporidium spp, Toxoplasma gondii, Mycobacterium avium-intracellulare, M avium complex, CMV, EBV

149
Q

What is the DNA structure of poxviruses?

A

Enveloped, double-stranded, linear DNA (this is the largest of the DNA viruses)

150
Q

What virus causes croup?

A

Parainfluenza virus

151
Q

What is the pathophysiology of prion disease?

A

Normal prion protein (PrPc) converts to β-pleated sheets (PrPsc), which accumulate in the central nervous system

152
Q

What vascular pathology can occur with hepatitis C?

A

Leukocytoclastic vasculitis

153
Q

In contrast to the other picornaviruses, what type of infection does rhinovirus not cause?

A

Gastrointestinal tract infections; it is acid labile and destroyed by stomach acid

154
Q

Name 5 medically significant conditions caused by coxsackieviruses.

A

Aseptic meningitis, pericarditis, herpangina (mouth blisters/fever), myocarditis, and hand/foot/mouth disease

155
Q

To what viral family does hepatitis B virus belong?

A

Hepadnaviridae

156
Q

What malignancy is associated with human papillomavirus infection in the population with HIV/AIDS?

A

Squamous cell carcinoma of the anus or cervix

157
Q

Name the 7 DNA viruses.

A

Hepadnavirus, Herpesvirus, Adenovirus, Poxvirus, Parvovirus, Papillomavirus, and Polyomavirus (HHAPPPPy viruses)

158
Q

Name 6 medically significant conditions caused by flaviviruses.

A

Hepatitis C, yellow fever, St. Louis encephalitis, Zika virus infection, West Nile disease (meningoencephalitis, flaccid paralysis), and dengue

159
Q

How can cytomegalovirus be transmitted?

A

Via sexual contact, transfusion, urine, saliva, organ transplants, and congenitally

160
Q

Chronic hepatitis B can have what hematologic abnormality?

A

Pancytopenia secondary to aplastic anemia

161
Q

Which 2 viruses in the picornavirus family are not enteroviruses?

A

Rhinovirus and HAV

162
Q

Which types of hepatitis can have a carrier state?

A

Hepatitis B, C, and D

163
Q

What prion disease is notable in tribal populations practicing human cannibalism?

A

Kuru

164
Q

What is the Tzanck test?

A

A smear of an open vesicle used to detect multinucleated giant cells seen in herpes simplex virus (HSV) infections (HSV-1, HSV-2, VZV; Tzanck heavens I do not have herpes)

165
Q

Rhinovirus causes what type of infection in humans?

A

The common cold (rhino has a runny nose)

166
Q

What complication may occur to a fetus exposed to parvovirus B19?

A

Hydrops fetalis (due to RBC destruction) and possibly death

167
Q

What are the viral receptors for HIV?

A

CD4, CXCR4, and CCR5

168
Q

What signs and symptoms are characteristic of all hepatitis viruses?

A

Fever, jaundice, and elevated levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST)

169
Q

What is the treatment of choice for Ebola?

A

There is no definitive treatment; supportive care, strict isolation, barrier practices for health care workers

170
Q

What are the 4 stages of untreated HIV infection?

A
  1. Flu-like, acute; 2. Feeling fine, latency; 3. Falling count, constitutional; 4. Final crisis, opportunistic infections (the Four stages)
171
Q

What hepatitis virus is associated with polyarteritis nodosa?

A

Hepatitis B

172
Q

Which RNA viral family do the measles and mumps viruses belong to?

A

Paramyxoviruses

173
Q

What is the test of choice for determining maternal HIV transmission to a newborn child?

A

HIV viral load in the newborn

174
Q

What stage of hepatitis B infection does positive HBsAg, anti-HBe, and anti-HBc IgG indicate?

A

Chronic HBV (low infectivity)

175
Q

In patients with HIV, what virus can cause progressive multifocal leukoencephalopathy (PML)?

A

JC (Junky Cerebrum) virus

176
Q

What is the difference between immunoglobulin M (IgM) versus immunoglobulin G (IgG) hepatitis B core antibodies?

A

IgM is a marker for acute or recent disease; IgG is a marker for prior exposure or chronic infection

177
Q

What is the RNA structure of the hepevirus?

A

Non-enveloped, single-stranded, positive-sense, linear RNA with an icosahedral capsid

178
Q

What 3 virus families have circular RNA structures?

A

Arenaviruses, bunyaviruses, and delta viruses

179
Q

What are the criteria for the diagnosis of acquired immunodeficiency syndrome (AIDS)?

A

CD4+ count ≤200 cells/mm3, HIV ⊕ with AIDS-defining illness, or CD4+ <14%

180
Q

What viral strains are found in the flu shot?

A

Viral strains that are most likely to appear during a flu season (due to the virus’ rapid genetic change); it is a reformulated vaccine

181
Q

Which RNA virus causes croup?

A

Parainfluenza

182
Q

How does the monospot test work?

A

Detects heterophile antibodies by the agglutination of sheep or horse red blood cells

183
Q

What are the viral receptors for CMV?

A

Integrins (heparan sulfate)

184
Q

What patient population has a high mortality rate if infected with hepatitis E virus?

A

Pregnant women (HEV: Enteric, Expectant mothers, Epidemic)

185
Q

An outdoorsman presents to the emergency department with a high fever, black-colored vomitus, and jaundice. How is the likely causative organism transmitted?

A

Via the Aedes mosquito (diagnosis: yellow fever)

186
Q

In what patient population do you typically see Epstein-Barr virus infection?

A

Teenagers and young adults

187
Q

What is the mechanism by which rabies causes infection?

A

Binds to acetylcholine receptors and migrates retrogradely up the axon via dynein motor proteins to the CNS

188
Q

What is the name for the dark, violaceous plaques/nodules resembling vascular proliferation caused by human-herpes virus 8?

A

Kaposi sarcoma

189
Q

What infection in patients with HIV/AIDS presents with cough, fever, and dyspnea with CD4+ count <200 cells/mm3, and the chest x-ray shows bilateral ground-glass opacities?

A

Pneumocystis jirovecii pneumonia

190
Q

The Centers for Disease Control no longer recommends what confirmatory testing for HIV?

A

Western blots

191
Q

What biopsy findings are associated with a Histoplasma capsulatam infection in patients with HIV/AIDS?

A

Macrophages contain oval yeast cells (presents with fever, fatigue, weight loss, cough, nausea, vomiting, dyspnea, and diarrhea)

192
Q

In what age group do diseases caused by paramyxoviruses predominate?

A

Infants and children

193
Q

Which diseases are caused by arboviruses (RNA viruses transmitted by arthropods)?

A

Colorado tick, Yellow, dengue, Zika, St. Louis/Eastern/Western equine/California encephalitis, Crimean-Congo, West Nile, Chikungunya, Sandfly/Rift Valley

194
Q

What 2 vaccines can be used for poliovirus infections?

A

Salk (IPV) and Sabin (OPV)

195
Q

What clinical manifestations does prion PrPsc accumulation cause?

A

Spongiform encephalopathy, ataxia, dementia, death

196
Q

How is Ebola diagnosed?

A

Perform reverse transcription polymerase chain reaction (RT-PCR) within 48 hours of symptom onset

197
Q

Which animal bites are most likely to result in rabies infection in the United States?

A

Bat, raccoon, skunk bites (all more common causes of rabies than dog bites)

198
Q

Which DNA virus is not icosahedral in shape?

A

Poxvirus (it is complex)

199
Q

How does cytomegalovirus infection present on fundoscopy?

A

Cotton-wool spots

200
Q

Name the 2 RNA viruses that are retroviruses.

A

Human immunodeficiency virus (HIV) and human T-lymphotropic virus (HTLV)

201
Q

Which herpesvirus is the most common cause of sporadic encephalitis?

A

Herpes simplex virus-1

202
Q

What RNA virus family does rabies belong to?

A

Rhabdoviruses

203
Q

Which viral family includes the hepatitis D virus?

A

Delta viruses

204
Q

Which cells do filoviruses target?

A

Endothelial cells, phagocytes, and hepatocytes

205
Q

Which well-known RNA virus family has reverse transcriptase?

A

Retrovirus

206
Q

In 2009, the H1N1 influenza A pandemic was caused by a complex viral genetic event. What was the event?

A

Reassortment (viruses with segmented genomes exchange segments); in this case, complex reassortments among human, swine, and avian viruses

207
Q

Which hepatitis viruses do not have carrier states?

A

Hepatitis A and E

208
Q

If you test for HIV-1 antibodies and receive an indeterminate result, which test can you subsequently order to better assess the patient’s HIV status?

A

An HIV-1 nucleic acid test (NAT)

209
Q

To what common sterilization procedure are prion diseases known to be resistant?

A

Standard autoclaving

210
Q

A patient has fever, black emesis, and scleral icterus. Liver biopsy reveals Councilman bodies (eosinophilic apoptotic globules). To which viral family does the virus belong?

A

Flavivirus; diagnosis: yellow fever virus, which is also an arbovirus (Flavi means yellow or jaundiced)

211
Q

What is the RNA structure of the rhabdovirus?

A

Enveloped, single-stranded, negative-sense, linear RNA with a helical capsid

212
Q

Which virus in the reovirus family causes fatal diarrhea in children?

A

Rotavirus

213
Q

Describe the structure of all herpesviruses.

A

Enveloped, double-stranded, and linear DNA viruses

214
Q

What is the mechanism for how parvovirus causes erythema infectiosum?

A

By infecting RBC precursors and endothelial cells

215
Q

How do you evaluate response to antiretroviral therapy for HIV?

A

Test the amount of viral RNA in plasma; higher viral loads indicate a poorer prognosis

216
Q

Coltivirus is the causative agent for which illness?

A

COLTIvirus causes COLorado TIck fever

217
Q

At what CD4+ count are acquired immunodeficiency syndrome- (AIDS) defining illnesses expected to emerge in HIV?

A

<200 cells/mm3

218
Q

What picornavirus causes the “common cold?”

A

Rhinovirus

219
Q

What cells are affected in Kaposi sarcoma?

A

It is a neoplasm of the endothelial cells of the vasculature

220
Q

What hematologic manifestations can occur in hepatitis C infection?

A

Essential mixed cryoglobulinemia, B-cell non-Hodgkin lymphoma, idiopathic thrombocytopenic purpura, and autoimmune hemolytic anemia

221
Q

How does cytomegalovirus (CMV, HHV-5) establish latency?

A

CMV establishes latency in mononuclear cells

222
Q

Describe the progression of rabies infection.

A

Fever and malaise leading to agitation, photophobia, hydrophobia, hypersalivation, then paralysis, coma, and death

223
Q

What fatal bacterial infections can occur after influenza?

A

Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae

224
Q

Name 8 naked (nonenveloped) viruses.

A

Parvovirus, Adenovirus, Papillomavirus, Polyomavirus, Calicivirus, Picornavirus, Reovirus, and Hepevirus (give PAPP smears and CPR to a naked hippie)

225
Q

How many RNA segments do Bunyaviruses, Orthomyxoviruses, Arenaviruses, and Reoviruses each have, respectively?

A

3, 8, 2, and 10-12 (BOARding flight 382 in 10-12 minutes)

226
Q

Name 5 medically significant members of the picornavirus family.

A

Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, HAV (PERCH)

227
Q

What is the RNA structure of the bunyavirus?

A

Enveloped, single-stranded, negative-sense, circular (in 3 segments) RNA with a helical capsid

228
Q

Individuals with HIV are at high risk for what types of cancers when infected with the Epstein-Barr virus?

A

Non-Hodgkin lymphoma, CNS lymphoma

229
Q

If the receptor CD21 is blocked, what virus will have difficulty infecting the cells?

A

Epstein-Barr virus (EBV)

230
Q

Which herpesviruses are transmitted in respiratory secretions versus via sexual contact?

A

HSV-1, Epstein-Barr virus, and varicella-zoster virus are transmitted in respiratory secretions; HSV-2, cytomegalovirus, and HHV-8 are transmitted by sexual contact

231
Q

How are HIV envelope proteins acquired?

A

Acquired via budding from the host cell plasma membrane

232
Q

Compare the incubation periods of hepatitis A, B, C, and E.

A

Hepatitis A and E: short (weeks); B and C: long (months)

233
Q

What is the role of the surface F (fusion) protein that is common to all paramyxoviruses?

A

Causes respiratory epithelial cells to fuse and become multinucleated

234
Q

What superinfection could worsen the prognosis of active hepatitis B infection?

A

A superinfection with hepatitis D virus

235
Q

What are severe complications of Ebola?

A

DIC (diffuse intravascular coagulation), diffuse hemorrhage, shock, death (high mortality rate)

236
Q

Where does HIV replicate during the latent phase?

A

Lymph nodes

237
Q

Describe the structure of orthomyxoviruses.

A

Enveloped, negative-sense, single-stranded RNA viruses with 8 segments

238
Q

Why do negative-stranded RNA viruses carry RNA-dependent RNA polymerase?

A

To transcribe the negative strand to a positive strand in the host cell in order to replicate

239
Q

What are possible central nervous system sequelae of measles?

A

Subacute sclerosing panencephalitis (years later) and encephalitis (1:2000 cases)

240
Q

In phenotypic mixing, how is the tropism (infectivity) of a progeny virus determined?

A

By which parent virus passes along its coat to the progeny virus

241
Q

What is the most common cause of measles-associated death in children?

A

Pneumonia

242
Q

What prion disease causes sporadic, rapidly progressive dementia?

A

Creutzfeldt-Jakob disease

243
Q

Describe the common skin findings associated with molluscum contagiosum.

A

Flesh-colored papules with central umbilication

244
Q

What disease does respiratory syncytial virus (RSV) cause in babies?

A

Bronchiolitis

245
Q

What is the RNA structure of the retrovirus?

A

Enveloped, single-stranded, positive-sense, linear (2 copies) RNA with either an icosahedral capsid (HTLV) or a complex, conical capsid (HIV)

246
Q

What is a patient’s HIV status if the nucleic acid test (NAT) is negative but HIV Ag/Ab immunoassay is positive?

A

HIV ⊖, as the HIV Ag/Ab immunoassay was likely a false positive

247
Q

What virus can act like Epstein-Barr virus (EBV) but have a negative monospot test?

A

Cytomegalovirus (human herpesvirus type-5)

248
Q

In viral genetics, what is the definition of reassortment?

A

The exchange of genetic material among viruses with segmented genomes (eg, the influenza virus)

249
Q

What DNA virus in adults can cause pure RBC aplasia and rheumatoid arthritis-like symptoms?

A

Parvovirus B19

250
Q

What human papillomavirus (HPV) serotypes are most commonly associated with cervical cancer?

A

16 and 18

251
Q

What is the incubation period before symptom onset in rabies?

A

Weeks to months

252
Q

What is the source of the HBeAg found in the serum of a patient infected with hepatitis B?

A

Secretion by infected hepatocytes into the circulation; it is not part of the mature HBV virion

253
Q

What should be done for postexposure prophylaxis in rabies?

A

Clean the wound and administer killed rabies vaccine and rabies immune globulin (passive-active immunity)

254
Q

Coronaviruses are the causative agents of what 3 diseases?

A

Common cold, Middle East respiratory syndrome (MERS), and severe acute respiratory syndrome (SARS)

255
Q

What antigen is associated with the core of hepatitis B virus?

A

HBcAg

256
Q

What common diseases are possible in the population with HIV/AIDS when the CD4+ count is <500 cells/mm3?

A

Candida albicans oral thrush, Epstein-Barr virus oral leukoplakia, human herpesvirus-8 Kaposi sarcoma, and human papillomavirus squamous cell carcinoma

257
Q

During which phase of HIV infection does the CD8+ T-cell count decline the most rapidly?

A

Systemic immunodeficiency/AIDS-defining illnesses phase

258
Q

Why are naked nucleic acids of negative-strand ssRNA and dsRNA viruses not infectious?

A

They require polymerases found in the complete virion to become infectious

259
Q

What is the mechanism of action of palivizumab?

A

Monoclonal antibody against the surface F protein of RSV (respiratory syncytial virus)

260
Q

What infection in patients with HIV/AIDS presents with pleuritic chest pain, hemoptysis, and a CD4+ count <100 cells/mm3?

A

Aspergillus fumigatus

261
Q

Which RNA virus family does the influenza virus belong to?

A

Orthomyxoviruses

262
Q

How are human herpes-viruses 6 and 7 transmitted?

A

Saliva

263
Q

Name the proteins for which each of these HIV genes code: env, gag, pol.

A

env: gp120 and gp41; gag: p24 and p17; pol: Reverse transcriptase, Integrase, Protease (RIP “Pol” [Paul])

264
Q

What type of infections might be seen with HIV when the CD4+ count is 200-400 cells/mm3?

A

Skin and mucous membrane infections

265
Q

Purified nucleic acids from which 2 dsDNA viruses are not considered infectious?

A

Poxvirus and hepatitis B virus (they require nonhuman enzymes for replication)

266
Q

What disease in patients with HIV/AIDS presents with neurological dysfunction (eg, gait and cognitive impairment) and a brain MRI that shows nonenhancing areas of demyelination?

A

Progressive multifocal leukoencephalopathy (due to JC virus reactivation); CD4+ count <200 cells/mm3

267
Q

What is the RNA structure of the reovirus?

A

Non-enveloped, double-stranded, linear RNA in 10-12 segments with a double icosahedral capsid

268
Q

Which 2 diseases are caused by arenaviruses?

A

Lymphocytic choriomeningitis (from LCMV) and Lassa fever encephalitis (spread by rodents)

269
Q

What viruses are part of the Togavirus family?

A

Toga CREW - Chikungunya virus, Rubella, Eastern and Western equine encephalitis

270
Q

What herpesvirus is the most common cause of mononucleosis?

A

Epstein-Barr virus (human herpesvirus-4)

271
Q

Name 4 medically important paramyxoviruses.

A

Parainfluenza virus, Respiratory syncytial virus, Mumps, and Measles (PaRaMyxovirus)

272
Q

Describe the lymph node biopsy findings of a patient with measles.

A

Warthin-Finkeldey giant cells (fused lymphocytes) present in a background of paracortical hyperplasia

273
Q

Compare the incubation periods of hepatitis D (HDV) with hepatitis B (HBV) superinfection versus HBV coinfection.

A

D: short when superinfection (HDV after HBV), long when coinfection (HDV with HBV)

274
Q

The HIV RNA levels peak during which phases of infection?

A

Acute infection phase and systemic immunodeficiency/AIDS-defining illnesses phase

275
Q

A recent South American emigrant gives birth to an infant with microcephaly. You suspect a viral infection as the cause. What is the most likely diagnosis?

A

Zika virus, transmitted by the mother to the fetus during development

276
Q

Why are the hepatitis B, C, and D viruses unable to spread via the fecal-oral route?

A

Unlike naked viruses (eg, HAV and HEV: the vowels hit your bowels), enveloped viruses are killed in the gut

277
Q

What CD4+ count is associated with Toxoplasma gondii infection?

A

<100 cells/mm3

278
Q

Which hepatitis virus is most likely to progress to cirrhosis or carcinoma?

A

Hepatitis C; most likely to progress to Cirrhosis or Carcinoma

279
Q

All segmented viruses have what type of viral genome?

A

RNA

280
Q

Describe the symptoms/signs of serum sickness.

A

Fever, arthralgias, rash; can represent initial infection with hepatitis B

281
Q

What is the function of the hepatitis B DNA polymerase?

A

Completes partial double-stranded DNA upon viral entry and reverse transcribes viral RNA to DNA for progeny genome synthesis

282
Q

What cancers are associated with Ebstein-Barr virus?

A

Lymphomas (endemic Burkitt), lymphoproliferative disease in transplant patients, and nasopharyngeal carcinoma

283
Q

What disease process should you consider in the population with HIV/AIDS with CD4+ count <200 cells/mm3, progressive memory loss, and an otherwise negative infectious work-up?

A

HIV dementia

284
Q

How is the reovirus genome unique among RNA viruses?

A

It has double-stranded RNA; all other RNA viruses are single stranded

285
Q

The genome of virus A is coated with surface proteins from virus B. Whose genetic material will the subsequent progeny of this newly formed virus have?

A

The progeny will have virus A genetic material with virus A coating; this is phenotypic mixing

286
Q

Which antibody is protective against hepatitis B infection acquired after recovery from an infection or vaccination?

A

Hepatitis B surface antibody (anti-HBs)

287
Q

What viral infection is associated with aplastic crises in sickle cell disease?

A

Parvovirus B19

288
Q

Once picornavirus RNA has entered the cell, what processing steps yield functional viral proteins?

A

The RNA is translated into a single polypeptide, which is then cleaved by virus-encoded proteases into functional viral proteins

289
Q

What stage of hepatitis B infection does positive anti-HBs, anti-HBe, and anti-HBc IgG indicate?

A

Recovery stage

290
Q

What is the difference between testing positive for HBeAg versus anti-HBe in terms of transmissibility?

A

HBeAg indicates active viral replication (high transmissibility); anti-HBe indicates low transmissibility

291
Q

How does CNS lymphoma differ from a Toxoplasma gondii infection on a brain MRI of a patient who is HIV ⊕?

A

A solitary ring-enhancing lesion is usually seen in CNS lymphoma; multiple lesions are usually found in a Toxoplasma gondii infection

292
Q

How do intramuscular and intranasal flu vaccines differ?

A

Injection contains killed virus; nasal spray has live mutant virus that is temperature sensitive and replicates in the nose (not the lungs)

293
Q

What virus can cause conjunctivitis, myocarditis, and febrile pharyngitis and has double-stranded and linear DNA?

A

Adenovirus

294
Q

Why are contact sports avoided in patients with mononucleosis?

A

Risk of splenic rupture

295
Q

What is the pathophysiology of the “blueberry muffin” rash seen in congenital rubella?

A

Dermal extramedullary hematopoiesis

296
Q

What are the tests of choice for cryptococcal meningitis infection?

A

India ink stain to reveal yeast with a large capsule, or test directly for the capsular antigen

297
Q

What is a pseudovirion?

A

The genetic material of one virus coated by the surface proteins of a different virus

298
Q

Structurally, what type of virus is a picornavirus?

A

A small RNA virus (picoRNAvirus = small RNA virus)

299
Q

How are arboviruses transmitted?

A

By arthropods (mosquitoes, ticks) (arbovirus, arthropod borne)

300
Q

What would you see on the liver biopsy of a patient infected with hepatitis A?

A

Hepatocyte swelling, Councilman bodies, and monocyte infiltration

301
Q

Use of what antibiotic in mononucleosis can cause a characteristic maculopapular rash?

A

Amoxicillin (prescribed for presumed streptococcal pharyngitis when diagnosis is actually mononucleosis)

302
Q

What is the RNA structure of the togavirus?

A

Enveloped, single-stranded, positive-sense, linear RNA with an icosahedral capsid

303
Q

What is the capsid symmetry of the hepatitis D virus (a delta virus)?

A

Uncertain (recall that hepatitis D is a “defective” virus that requires HBV co-infection)

304
Q

Hepatitis D virus (HDV) infection needs coinfection with hepatitis B to supply the envelope protein for HDV. What is this called?

A

Complementation

305
Q

What sequelae of infection can occur after measles in an immunocompromised patient?

A

Giant cell pneumonia, occurs mostly in the immunosuppressed

306
Q

What is expected on a biopsy of bacillary angiomatosis in a patient who is HIV ⊕?

A

Neutrophilic inflammation caused by Bartonella spp

307
Q

What condition is caused by West Nile virus?

A

Meningoencephalitis

308
Q

What is the test of choice for herpes simplex virus (HSV) encephalitis?

A

HSV polymerase chain reaction (PCR) of the cerebrospinal fluid (CSF)

309
Q

Structurally, what are the 4 main classes of viruses?

A

Naked viruses with icosahedral capsids, enveloped viruses with icosahedral capsids, enveloped viruses with helical capsids, and bacteriophages

310
Q

Which family of RNA viruses is NOT single-stranded RNA?

A

The Reoviridae family; all are single-stranded RNA except “repeatovirus” (reovirus), which is double-stranded RNA

311
Q

What are the 4 Cs of measles?

A

Cough, Coryza, Conjunctivitis, and “C”oplik (Koplik) spots

312
Q

Which family of DNA viruses does not contain double-stranded DNA?

A

Parvoviridae, which has single-stranded DNA (Parvovirus is part-of-a-virus)

313
Q

What type of viral genomic structure is necessary for viral genome reassortment?

A

A segmented genome

314
Q

What does a positive test for hepatitis B surface antigen indicate?

A

Active hepatitis B infection

315
Q

What endoscopic and biopsy findings are seen in Candida albicans esophagitis?

A

White plaques on endoscopy; biopsy shows yeast and pseudohyphae

316
Q

Rubella is part of which prenatal screening panel?

A

ToRCHeS infection

317
Q

What stage of hepatitis B infection does positive HBsAg, HBeAg, and anti-HBc IgG indicate?

A

Chronic HBV (high infectivity)

318
Q

Name the 2 major antigens of the influenza virus.

A

Hemagglutinin and neuraminidase

319
Q

For which hepatitis virus is a chronic carrier state common?

A

Carrier states are very common with HCV

320
Q

Retroviruses and the hepatitis B virus have what enzyme in common?

A

Reverse transcriptase

321
Q

Describe the shape of the rabies virus.

A

Bullet-shaped

322
Q

How does the rash caused by roseola infantum spread?

A

Starts on the trunk and then spreads to extremities

323
Q

What do IgG antibodies to HBcAg signify?

A

Chronic infection or prior exposure to hepatitis B

324
Q

Which herpes simplex virus is more likely to cause viral meningitis?

A

Herpes simplex virus-2 (HSV-2)

325
Q

What is a patient who is HIV ⊕ generally at risk for as the CD4+ cell count drops?

A

Reactivation of past infections (eg, TB, shingles, HSV), non-Hodgkin lymphoma, dissemination of bacterial/fungal infections

326
Q

How might a patient infected with hepatitis A virus typically present?

A

Asymptomatic and Acute (HAV)

327
Q

What infection in HIV presents with white patches on the lateral side of the tongue that cannot be scraped off?

A

Oral hairy leukoplakia (due to Epstein-Barr virus)

328
Q

What does the HIV-1/2 Ag/Ab immunoassay detect for in serum?

A

Viral p24 capsid protein antigen and IgG antibodies to HIV-1/2

329
Q

What is the viral structure and family of a rotavirus?

A

It is a segmented, double-stranded RNA virus in the reovirus family

330
Q

After a positive nucleic acid test (NAT) for HIV, which test do you use to determine appropriate antiretroviral therapy?

A

HIV genotype testing

331
Q

Where does human herpes virus-3 lie latent?

A

In the dorsal roots or trigeminal ganglia

332
Q

What is the test of choice for cryptosporidium infection in patients with HIV/AIDS?

A

An acid-fast stain of the stool sample, showing acid-fast oocysts in the stool (presents clinically with chronic watery infections)

333
Q

From what cellular structure in their hosts do the herpesviruses acquire their envelopes?

A

Nuclear Membrane

334
Q

What does the human immunodeficiency virus do during the acute phase of infection?

A

Widespread dissemination and seeding of the lymphoid organs

335
Q

Name the 4 families of RNA viruses that have no envelope.

A

Reoviruses, picornaviruses, hepeviruses, and caliciviruses

336
Q

What DNA virus is associated with “milkmaid blisters?”

A

Cowpox

337
Q

What possible sequelae can occur in mumps, especially after puberty?

A

Sterility, particularly when it affects boys after puberty

338
Q

Why is HIV-1/2 antigen/antibody testing not recommended in babies with suspected HIV?

A

Due to maternally transferred HIV antibodies; need to check the viral load to determine the status

339
Q

Name 4 segmented RNA viruses.

A

Bunyaviruses, Orthomyxoviruses (influenza), Arenaviruses, Reoviruses (BOAR)

340
Q

What is the DNA structure of adenoviruses?

A

Non-enveloped, double-stranded, linear DNA

341
Q

Does a patient with a CD4+ count of 150 cells/mm3 with no history of acquired immunodeficiency syndrome- (AIDS) defining illnesses have AIDS?

A

Yes, because the patient’s CD4+ count is <200 cells/mm3

342
Q

Cranial nerve V1 involvement of varicella-zoster virus can cause what disease?

A

Herpes zoster ophthalmicus

NBME Micro (36 decks)

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