163 - Exanthematous Viral Diseases Flashcards
Prodrome of fever, cough, coryza and conjunctivitis
Measles
_____ spots are pathognomonic of measles
Koplik
Measles virus is a highly contagious, single-stranded, enveloped RNA virus that is a member of the _____ family
Paramyxoviridae
Y/N: Humans are the only natural hosts of measles
Yes
Koplik spots are tiny white lesions – “_____” – surrounded by an erythematous halo
Grains of sand
Koplik spots are typically found on
Buccal mucosa near the second molars
Koplik spots typically occur _____ and only last _____
48 hours prior to the onset of rash
12 to 72 hours
Measles exanthem begins on the
Forehead and behind the ears
Viral detection of measles via PCR is most successful when collection occurs within
3 days of the rash’s onset
Measles IgM is typically positive on the first day of the rash and remains positive for at least _____ afterward
30 days
Y/N: Within the first 72 hours of the rash, measles IgM assay may be falsely negative
Yes
Measles is considered contagious
5 days prior to the onset of the rash until 4 days after the onset of the rash
Most measles deaths are attributed to
Respiratory illness or
Encephalitis
The WHO recommends that _____ should be administered to all children with measles regardless of their country of residence
Vitamin A
Vitamin A dosage for measles
200,000 IU per day or
100,000 IU per day for infants
on 2 consecutive days
Antiviral medication that has been used in children with severe measles disease or an immunocompromised state
Ribavirin
Individuals at risk of severe illness and complications
Infants younger than 1 year of age
Pregnant women
Unimmunized
Immunocompromised
Individuals at risk of severe illness and complications should be given measles immunoglobulin if presenting within _____ of exposure
6 days
Measles immunoglobulin dosage
IM - 0.5 mL/kg; maximum dose: 15 mL
IV - 400 mg/kg
In healthy individuals, the _____ should be given to boost immunity if it can be administered within 72h hours of measles exposure
Measles-mumps-rubella vaccine
Measles vaccine administration
At 12 to 15 months
Prior to school entry, between 4 and 6 years old
Enveloped positive-stranded RNA virus in the Togaviridae family
Rubella
Rubella-infected individuals shed virus for
5 to 7 days before and up to 14 days after onset of rash
Risk of transplacental infection is greatest to a fetus exposed to the virus in the
First trimester
Congenitally infected infants may shed the virus through urine, blood, and nasopharyngeal secretions for up to _____ after birth
12 months
Individuals at risk of severe illness and complications should be given measles immunoglobulin if presenting within _____ of exposure
6 days
Measles immunoglobulin dosage
IM - 0.5 mL/kg; maximum dose: 15 mL
IV - 400 mg/kg
In healthy individuals, the _____ should be given to boost immunity if it can be administered within 72h hours of measles exposure
Measles-mumps-rubella vaccine
Measles vaccine administration
At 12 to 15 months
Prior to school entry, between 4 and 6 years old
Enveloped positive-stranded RNA virus in the Togaviridae family
Rubella
Rubella-infected individuals shed virus for
5 to 7 days before and up to 14 days after onset of rash
Risk of transplacental infection with rubella is greatest to a fetus exposed to the virus in the
First trimester
Rubella-specific IgM antibody can be detected up to
8 weeks after infection
As the rubella prodrome resolves and the rash begins to appear, some patients develop an enanthem consisting of tiny red macules on the soft palate and uvula
Forchheimer spots
Y/N: Forchheimer spots is diagnostic for rubella
No - not diagnostic
The rash of rubella usually begins to disappear in
2 to 3 days
Lymphadenopathy in rubella is usually most severe in the
Posterior cervical, suboccipital, and postauricular lymph nodes
Lymphadenopathy in rubella is noted up to _____ before the rash appears
7 days
Adults, particularly women (up to 70%), may develop _____ with rubella infection
Arthritis of small and large joints
Joint symptoms in rubella often first appear
As the rash fades
Rubella-specific IgM antibody can be detected up to
8 weeks after infection
Neonatal manifestations of congenital rubella infection
Growth retardation
Interstitial pneumonitis
Radiolucent bone disease
Hepatosplenomegaly
Thrombocytopenia
Dermal erythropoiesis ("blueberry muffin lesions")Rubella IgM antibody can be detected from _____ to _____
Birth
1 month of age
The B19 virus belongs to the family Parvoviridae and the genus
Erythrovirus
Limited data indicate that _____ as postexposure prophylaxis for rubella-susceptible patients may decrease infection, viral shedding, and rate of viremia
IM immunoglobulin (0.55 mL/kg)
Contact isolation is recommended for infants with rubella until they are at least ____ old or repeated cultures are negative after _____ of age
12 months
3 months
It is imperative that individuals at risk for rubella infection are immunized, such as
Health care workers
Military recruits
College students
Recent immigrants
Receptor of parvovirus
Blood group P antigen (globoside)
Pruritic erythema, edema, and petechiae of the hands and feet, fever and oral erosions in adolescents
Papular purpuric gloves-and-socks syndrome
Persons with erythema infectiosum are infectious
Only before the onset of the rash
Causative agent of erythema infectiosum and papular purpuric gloves-and-socks syndrome
Parvovirus B19
Smallest single-stranded DNA-containing virus known to infect humans
Lacks an envelope and contains single-stranded DNA
Parvovirus B19
Y/N: Animal parvoviruses are thought to be transmissible to humans
No - not thought to be transmissible
The more serious manifestations of parvovirus infection relate to the fact that the virus infects and lyses
Erythroid progenitor cells
Receptor of parvovirus
Blood group P antigen (globoside)
Y/N: Most infections caused by B19 in children are asymptomatic and unrecognized
Yes
Most common clinical picture associated with parvovirus B19
Fifth disease
Fifth disease eruption typically lasts
5 to 9 days
Parvovirus B19 IgM can be detected within _____ and is present for up to _____ in many cases
A few days after onset of illness
6 months
Primary manifestation of B19 viral infection in adults
Acute arthropathy
Acute arthrophathy in adults occurs mainly in _____ and affects the _____
Women
Knees and small joints of the hands
The constitutional symptoms of parvovirus B19 are usually (less/more) severe in adults than in children
More
Chronic anemia B19 usually resolves if treated with
IV gamma-globulin
Papular purpuric gloves-and-socks syndrome seems to affect
Teenagers and adults
May be necessary in transient aplastic crisis, and most patients recover in week
Red blood cell transfusion
Parvovirus B19 IgM can be detected within _____ and is present for up to _____ in many cases
A few days after onset of illness
6 months
Parvorirus B19 IgG can be identified by the _____ of illness and lasts for _____
Seventh day
Years
Considered the test of choice in an immunocompromised patient, and to confirm fetal infection with parvovirus B19
PCR
Caveat to PCR testing in parvovirus B19 infection
DNA fragments may be present for more than a year after infection, however this does not always indicate that the viable virus is present
Also known as human herpesvirus 4
Enveloped, double-stranded DNA virus
Epstein-Barr virus
Parvovirus B19 is the most common causes of _____ in patients with chronic hemolytic anemias
Transient aplastic crisis
Morbilliform exanthem after primary infection with infectious mononucleosis is most common after administration of
Ampicillin or amoxicillin
Most common complication of intrauterine infection with B19
Nonimmune fetal hydrops
Approximately _____% of women of childbearing age are immune to parvovirus infection because of prior infection
50
Risk factors for early seropositivity with EBV
Lower household income
Parental education level
Uninsured status
Being Mexican American or Black (non-Hispanic)
Y/N: Patients with aplastic crisis or immunosuppression with chronic B19 anemia may have high-titer viremia and are particularly infectious
Yes
Also known as human herpesvirus 4
Epstein-Barr virus
Characterized by the triad of fever, lymphadenopathy, and pharyngitis
Caused by EBV
Infectious mononucleosis
Morbilliform exanthem after primary infection with EBV is most common after administration of
Ampicillin or amoxicillin
Malignancies associated with EBV
Oral hairy leukoplakia
Nasopharyngeal carcinoma
Kikuchi histiocytic necrotizing lymphadenitis
Certain types of cutaneous T-cell lymphoma
EBV is a worldwide pathogen with more than ____% of adults latently infected
90
Risk factors for early seropositivity with EBV
Lower household income
Parental education level
Uninsured status
Being Mexican American or Black (non-Hispanic)
Type of EBV which is found worldwide
EBV-1
Infectious mononucleosis is also referred to as the
“Kissing disease”
EBV is typically transmitted via
Saliva
After infectious mononucleosis, viral shedding continues for a median duration of
6 months
EBV infects B lymphocytes through the binding of the EBV glycoprotein _____ with _____ on the surface of B cells
gp350
CD21
A clonal expansion of _____ allows recovery from primary and reactivation infection and is the source of the atypical lymphocytes associated with EBV infection
Cytotoxic T lymphocytes
Inherited immunodeficiencies particularly associated with impaired immune responses to EBV infection
X-linked lymphoproliferative disease
GATA2 deficiency
Most common manifestation of EBV infection in adolescents and adults
Infectious mononucleosis
Lymphomatoid granulomatosis requires the initiation of
Chemotherapy
Suggestive features of primary EBV infection
Splenomegaly, posterior, as opposed to anterior
Cervical lymphadenopathy
Lymphocytosis with a predominance of atypical lymphocytes (defined as more than 10% of total lymphocytes)
Y/N: EBV infection during pregnancy is thought to be teratogenic
No - not thought to be teratogenic
Frequently occur in prepubertal or adolescent females and present as painful, multiple ulcers with red-purple ragged edges on the medial or outer surface of the labia minor
Caused by EBV infection
Lipschutz ulcers
Hallmarks: natural killer-cell phenotype (expression of CD2, CD56, and cytoplasmic CD3 but lack a surface of CD3), angioinvasion and necrosis
Strongly associated with EBV
Nasal-type extranodal natural killer/T cell lymphoma (ENK/T)
EBV-driven T-cell disorder
Development of vesicles, crusting, and varicellifom scarring
Distinguished by systemic symptoms, extensive facial edema, ulcerations and scarring, and lesions located in photoprotected sites
Histopathology reveals a monoclonal proliferation of T cells with a CD8 phenotype
Hydroa vacciniforme-like disease
Rare, angioinvasive proliferation of EBV-infected B cells and a reactive, polyclonal T-cell population
Pulmonary involvement is seen in almost all patients
Most often presents in the fourth to sixth decade
Lymphomatoid granulomatosis
Lymphomatoid granulomatosis requires the initiation of
Chemotherapy
Suggestive features of primary EBV infection
Splenomegaly, posterior, as opposed to anterior
Cervical lymphadenopathy
Lymphocytosis with a predominance of atypical lymphocytes (defined as more than 10% of total lymphocytes)
Heterophile antibody test frequently used to confirm infectious mononucleosis in adolescents and adults with classic symptoms because of its rapid turnaroud time and high specificity in the appropriate clinical setting
Monospot test
Sensitivity of rapid diagnosis heterophile antibody tests for EBV is approximately _____%
85
EBV _____ studies frequently used to monitor for posttransplantation lymphoproliferative disease as trending high viral loads serve as a marker for impending posttransplantation lymphoproliferative disease
Serum PCR
Often employed to confirm EBV infection in young children and when a suspicion for EBV infection remains high despite a negative heterophile antibody test
EBV-specific antibodies
Host IgM and IgG antibodies form against viral capsid antigen (VCA) and are positive during _____. IgM VCA wanes _____ after clinical illness and IgG VCA remains positive for life
Acute infection
3 months
EBV nuclear antigen (EBNA) is expressed when _____; consequently IgG to EBNA becomes positive usually _____ after symptoms develop
The virus establishes latency
6 to 12 weeks
A positive IgM BVA and negative IgG EBNA confirms
Acute infection
A positive _____ argues against an acute EBV infection
IgG EBNA
IgG to early antigen exists as 2 subsets, anti-D and anti-R. _____ antibodies occur during recent infection and resolve with recovery. The clinical significance of _____ antibodies is not clear
Anti-D
Anti-R
EBV _____ studies frequently used to monitor for posttransplantation lymphoproliferative disease as trending high viral loads serve as a marker for impending posttransplantation lymphoproliferative disease
Serum PCR
Monomorphic dome-shaped or flat-topped papules symmetrically distributed on face and extensor extremities
Associated with multiple viral triggers and immunizations
Gianotti-Crosti syndrome
Gianotti-Crosti syndrome is also known as
Infantile papular acrodermatitis
Papular acrodermatitis of childhood
Host risk factors associated with GCS
Young age
History of atopic dermatitis
Cutaneous findings in the newborn with congenital HCMV infection
Petechial rash
Jaundice
Blueberry muffin lesions
GCS is historically associated with _____ infection, but now more often triggered by _____
Hepatitis B
Epstein-Barr virus
Most common accompanying symptom of GCS
Pruritus
GCS usually fades over
10 to 60 days
Might last longer than most rashes associated with viruses
Also known as human herpesvirus 5
Human cytomegalovirus
Congenital infection with HCMV is a major cause of
Hearing loss
Most common congenital viral infection in humans
HCMV
Cutaneous findings in the newborn with congenital HCMV infection
Petechial rash
Jaundice
Blueberry muffin lesions
Perinatal infection with HCMV is very different from congenital HCMV infection, and is
Without diffuse visceral or CNS involvement
Cutaneous findings in perinatal HCMV infection
None
Approximately _____% of infectious mononucleosis cases are caused by HCMV`
10
Unlike EBV mononucleosis, HCMV-induced mononucleosis patients do not typically have
Pharyngitis and lymphadenopathy
HHV-6 primary infection often presents either as _____ or _____
Acute febrile illness Exanthem subitum (roseola infantum, sixth disease)
Most common cutaneous manifestations of HCMV disease in immunocompromised patients
Perianal and rectal ulceration
Gold standard for diagnosis of HCMV infection
Viral culture from blood
Can be used to identify primary infection in children younger than 12 months of age as they shed HCMV for longer periods of time
PCR
In immunocompromised patients, _____ for CMV is the most widely used test for diagnosis, and monitoring response to treatment
Quantitative nucleic acid amplification testing
Characteristic histologic feature of CMV infection
Cytomegalic cells with nuclear inclusions
Enlarged endothelial cells with large intranuclear inclusions and a clear halo (owl’s eye cells)
Improves hearing and neurodevelopmental outcomes in patients with symptomatic congenital HCMV infection
Oral valganciclovir
HHV-6 primary infection often presents either as _____ or _____
Acute febrile illness Exanthem subitum (roseola infantum, sixth disease)
HHV-6 is a common viral infection with up to _____% of the population acquiring the infection by 2 years of age
80
Primary infection with HHV-6 typically occurs between the ages of
6 months and 2 years when maternal passive immunity wanes
HHV-6 primary infection exhibits seasonal variation with the highest incidence in
Spring
HHV-(6a/6b) causes ES and reactivates in immunocompromised hosts. It is unclear what diseases, if any, are caused by HHV-(6a/6b)
6b
6a
HHV-6 preferentially infects
Activated CD4+ T lymphocytes
Cellular receptor for HHV-6 infection
Immune regulatory protein CD46
HHV-6 transmission occurs via
Shared saliva
Hallmark of exanthem subitum
“Rose”-colored macules and papules surrounded by a white halo
Exanthem subitum lasts for
3 to 5 days
A unique feature of ES is that it presents
1 day before to 1 o 2 days after the fever resolves
As opposed to most viral exanthems where eruptions occur at the onset of the illness
Children with ES may also have palpebral edema resulting in a “sleepy” appearance and erythematous papules on the soft palate (_____) that may precede the viral exanthem
Nagayama spots
Other diseases associated with HHV-6
Pityriasis rosea
Rosai-Dorfman disease
Drug-induced hypersensitivity syndrome
Diagnosis of HHV-7 active infection can only be made from
Acellular material such as CSF, serum, or plasma
Because the virus is latent in peripheral blood mononuclear cells and tissue
_____% of ES are caused by HHV-7
10
Primary infection with HHV-7 occurs during childhood, but (earlier/later) than, and at a (slower/faster) rate than, infection with HHV-6
Later
Slower
HHV-7 is a member of the _____ family
Beta-Herpesviridae
HHV-7 establishes persistent infection in the _____, and transmission is likely through _____
Salivary glands
Saliva
Reactivation of HHV-7 occurs (less/more) often than reactivation of HHV-6
More
The rash associated with HHV-7 is (lighter/darker) in color and occurs later in the course of the disease than HHV-6 associated ES
Lighter
Diagnosis of HHV-7 active infection can only be made from
Acellular material such as CSF, serum, or plasma
Because the virus is latent in peripheral blood mononuclear cells and tissue
Enteroviruses are small, single-stranded RNA picornaviruses and include
Echovirus
Coxsackieviruses A and B
Poliovirus
Most common cause of aseptic (viral) meningitis
Nonpolio enteroviruses
Viral exanthem seen most commonly in children in summer and fall
Erosions in the mouth and papulovesicles on the palms and soles
Hand-foot-mouth disease
HFMD is caused by
Coxsackievirus A16
Enterovirus 71
HFMD transmission
Fecal-oral route
Less commonly, respiratory inhalation
HMFD vesicles quickly erode and form yellow to gray, oval or “_____-shaped” erosions surrounded by an erythematous halo
Football
Most common serious complication associated with HFMD
Aseptic meningitis
(Coxsackievirus A16/Enterovirus 71), an important cause of HFMD outbreaks in Asia, is associated with severe illness
Enterovirus 71
Severe neurologic disease
Oral ulcerations, a defining feature in classic HFMD, found in nearly 100% of patients, are seen less frequently in _____ infection
Coxsackievirus A6
2 most common complications for CVA6
Desquamation of the hands and feet
Onychomadesis
Enteroviruses which cause eruptive pseudoangiomatosis
Echovirus 25
Echovirus 32
Pink papules that start in a large flexural region, become bilateral, but remain asymmetric
Unilateral laterothoracic exanthem
Unilateral laterothoracic exanthem is also called
Asymmetric periflexural exanthem of childhood
Unilateral laterothoracic exanthem has a seasonal variation and occurs most frequently in
Late winter and early spring
