25 - 163 - EXANTHEMATOUS VIRAL DISEASES Flashcards
Pathognomonic buccal mucosal finding in measles.
When does it occur?
Where is it frequently located?
- Koplik spots
- Occurs during prodrome phase
- Typically found on the buccal mucosa near the second molars
Morbilliform eruption of measles lasts for how many days
3 - 5 days
T/F. Humans are the only natural hosts of measles
True
Mode of transmission of measles
person-to-person contact or airborne respiratory secretions
Measles infectious droplets have been reported to remain airborne for up to how many hours, allowing for easy transmission in public spaces.
2 hours
Incubation period of measles
7 - 21 days
3 stages of measles
- Incubation period
- Prodrome
- Exanthem
Characterize the prodrome of measles
The prodrome consists of fever (as high as 40.5°C [104.9°F]), malaise, conjunctivitis (palpebral, extending to lid margin), coryza, and cough (brassy or barking) and can last up to 4 days.
Koplik spots are the pathognomonic enanthem of measles and develop during the prodrome.
The spots begin as small, bright red macules that have a 1- to 2-mm blue-white speck within them and are typically found on the buccal mucosa near the second molars
Koplik spots occur how many hours prior to the onset of the rash
48 hours
Koplik spots typically occur 48 hours prior to the onset of the rash and only last 12 to 72 hours
Koplik spots last for how many hours only
12 - 72 hours
Koplik spots typically occur 48 hours prior to the onset of the rash and only last 12 to 72 hours
Describe the measles exanthem
The measles exanthem consists of nonpruritic, erythematous macules and papules progressing in a cranial-to-caudal direction. The exanthem begins on the forehead and behind the ears (Fig. 163-2) and spreads to involve the neck, trunk, and extremities (Fig. 163-3). The hands and feet are involved.
Lesions may coalesce, especially on the face and neck. The rash usually peaks within 3 days and begins to disappear in 4 to 5 days in the order that it appeared. Desquamation and brownish dyspigmentation in fair patients can occur as the rash resolves.
Measles virus detection is most successful when collection occurs within how many days of the rash’s onset.
3 days
Give laboratory diagnostic tests for measles
- real-time reverse transcription polymerase chain reaction (PCR)
- serologic studies: (+) serum IgM antibody for measles confirms diagnosis; IgM is positive on the 1st day of the rash and remains positive for at least 30 days; fourfold increase in IgG titers (serum must be withdrawn in the convalescent stage)
Uncomplicated measles will last for how many days
10 - 12 days
When is a measles patient considered infectious
An infected patient is considered to be contagious 5 days prior to the onset of the rash until 4 days after the onset of the rash.
What are the complications of measles
- severe diarrhea;
- pneumonia (either viral or superimposed bacterial infection);
- otitis media;
- transient immunosuppression with lymphopenia and decreased cell-mediated immunity;
- encephalitis, and
- a rare form of a progressive neurodegenerative disease termed subacute sclerosing panencephalitis
What is the second line treatment of measles
Ribavirin
First-line treatment for Measles
■ Immunoglobulin, IM
■ Measles vaccine
■ Supportive care
■ Treat secondary infections
■ Vitamin A
- vitamin A (200,000 international units per day or 100,000 international units per day for infants) on 2 consecutive days and a reduced risk of measles mortality in children younger than 2 years old
Post-exposure prophylaxis can be given to which patients
Individuals at risk for severe illness and complications (infants younger than 1 year of age, pregnant women, unimmunized, and immunocompromised) should be given measles immunoglobulin if presenting within 6 days of exposure.
Individuals at risk for severe illness and complications (infants younger than 1 year of age, pregnant women, unimmunized, and immunocompromised) should be given measles immunoglobulin if presenting within how many days of exposure?
How do you give it?
6 days of exposure
Measles immunoglobulin can be given either via an IM (0.5 mL/kg; maximum dose: 15 mL) or IV route (400 mg/kg).
In healthy individuals, the measlesmumps-rubella (MMR) vaccine should be given to boost immunity if it can be administered within how many hours of measles exposure
72 hours
The American Academy of Pediatrics, recommends MMR at what age
12 - 15 months and then again prior to school entry, between 4 and 6 years old.
Infectious stage of german measles
Infected individuals shed virus for 5 to 7 days before and up to 14 days after onset of rash
The risk is greatest to a fetus exposed to the rubella virus in the what trimester
1st trimester
- Congenitally infected infants may shed the virus through urine, blood, and nasopharyngeal secretions for up to 12 months after birth, thus being a potential source of viral exposure to other susceptible individuals
Characterize the prodrome of german measles
The prodrome is characterized by low-grade fever, myalgia, headache, conjunctivitis, rhinitis, cough, sore throat, and lymphadenopathy; symptoms that may last up to 4 days and often resolve with appearance of rash.
What do you call the enanthem of german measles consisting of tiny red macules on the soft palate and uvula
Forchheimer spots
T/F: Forchheimer spots are pathognomonic for rubella
FALSE
Incubation period of german measles
14 - 17 days
How can you differentiate rubeola and rubella based on the cutaneous manifestations
- The exanthem of german measles, occurring 14 to 17 days after exposure, is characterized by pruritic pink to red macules and papules that begin on the face, quickly progressing to involve neck, trunk, and extremities
- Lesions on the trunk may coalesce, whereas those on the extremities often remain** more discrete. **
- The rash usually begins to disappear in 2 to 3 days, unlike rubeola, which can be more persistent and clears the head and neck first.
- Desquamation may follow resolution of the rash.
Review: exanthem of rubeola - NONPRURITIC, erythematous macules and papules pregressing in a cranial-to-caudlal direction. Peeks in 3 days and begins to disappear in 4 - 5 days in **THE ORDER IT APPEARED **
Lymphadenopathy in german measles is usually most severe in what locations
posterior cervical, suboccipital and postauricular lymph nodes
Standard and droplet precautions are recommended for patients with rubella for how many days after rash onset
7 days after rash onset
*Standard and droplet precautions are recommended for patients with rubella for 7 days after rash onset. p 2994
contagiuous: 5 - 7 days before and up to 14 days after rash onset
Rubella vaccine is typically administered as part of a threefold vaccine (MMR) or fourfold vaccine (MMR and varicella) at _______ months of age and again at ______ years of age.
12 to 15 months
4 - 6 years
Any woman receiving the rubella vaccine should not become pregnant for how many days
28 days
T/F: Infants of vaccinated breastfeeding mothers may become infected with rubella via breastmilk
True
This exanthem is characterized by symmetric polyarthritis, particularly of the small joints in adults.
PARVOVIRUS B19 INFECTION
The incubation period for erythema infectiosum
4 - 14 days
It is the smallest single-stranded DNA-containing virus known to infect humans
Parvovirus B19
primary manifestation of B19 viral infection in adults
Acute arthropathy
It occurs mainly in women and affects the knees and the small joints of the hands. Other joints, such as the spine and costochondral joints, are occasionally involved. This symmetric polyarthritis is usually of sudden onset and is self-limited but can be persistent or recurrent for months. It may mimic Lyme arthritis or rheumatoid arthritis.
T/F: Patients with erythema infectiosum are not infectious when exanthem/rash is present
True
After the rash of erythema infectiosum appears, B19 is usually not found in respiratory secretions or serum, suggesting that persons with erythema infectiosum are infectious only before the onset of the rash.
Papular purpuric gloves-and-socks syndrome is contagious when the eruption is present, in contrast to erythema infectiosum.
PAPULAR PURPURIC GLOVES ANDSOCKS SYNDROME is caused by what virus
Parvovirus B19
Patients usually have mild
prodromal symptoms of fatigue and low-grade fever, myalgia, and arthralgia. Subsequently, itchy, painful, symmetric edema and erythema of the distal hands and feet occurs. Purpuric papules appear on the hands and feet with abrupt demarcation at the wrists and ankles. The enanthem, if present, arises on the lips, soft palate, and buccal mucosa. The syndrome resolves spontaneously within 2 weeks. Importantly, papular purpuric gloves-and-socks syndrome is contagious when the eruption is present, in contrast to erythema infectiosum.
It is considered the test of choice in an immunocompromised patient, and to confirm fetal parvovirus B19 infection
PCR
True about measles except:
a. The measles virus enters the host via the respiratory mucosa or conjunctiva
b. Caused by a single-stranded, enveloped RNA virus
c. Forchheimer spots are the pathognomonic enanthem
d. Vitamin A (200,000 international units per day or 100,000 international units per day for infants) on 2 consecutive days and a reduced risk of measles mortality in children younger than 2 years old
C.
Page 2990. Koplik spots are the pathognomonic enanthem of measles and develop during the prodrome. The spots begin as small, bright red macules that have a 1- to 2-mm blue-white speck within them and are typically found on the buccal mucosa near the second molars. Koplik spots typically occur 48 hours prior to the onset of the rash and only last 12 to 72 hours. Koplik’ spots may be absent if a patient presents several days into the patient’s rash.
What is the proper scheduling for MMR vaccination?
a. 12 to 15 months of age and again at 4 to 6 years of age.
b. At birth
c. 2, 4, 6 and 18 months of age
d. 6 and 12 months of age
A
Blood group that is the receptor of parvovirus
d. Biopsy
a. ABO
b. Rh
c. P
d. Lewis
C
Page 2995. The blood group P antigen (globoside) is a receptor of parvovirus. Because some individuals lack P antigen, they are not susceptible to infection with B19
A 15-yo male presented with fever, lymphadenopathy and pharyngitis. He sought consult and was given ampicillin. 7 days after he developed generalized, pruritic, morbilliform rash. What etiologic agent caused this problem?
a. Measles virus
b. Rubella virus
c. Parvovirus
d. Epstein-Barr virus
D
Page 2999. Eruptions also frequently occur when patients with infectious mononucleosis are treated with antibiotics, classically ampicillin. This association was first described in the 1960s and coined the ampicillin rash.60 Beginning 7 to 10 days after the initiation of ampicillin, patients develop a generalized, pruritic, morbilliform rash with an erythematous or copper color that resolves in a week.
Cutaneous lesions seen in congenital human cytomegalovirus infection except:
a. Jaundice
b. Petechial Rash
c. Morbilliform Rash
d. Blueberry muffin lesions.
C
Page 3004. Cutaneous findings in the newborn include a petechial rash secondary to thrombocytopenia, jaundice caused by hepatitis and blueberry muffin lesions from dermal erythropoiesis.
What is the most common cause of Gianotti-Crosti Syndrome in developed countries?
a. Hepatitis B Virus
b. Hepatitis C Virus
c. Epstein-Barr Virus
d. Coxsackie Virus
C
Page 3003: In most developed countries, EBV is frequently cited as the most common cause of GCS.
What is the gold standard for the diagnosis of human cytomegalovirus (HCMV) infection?
a. PCR
b. Viral culture
c. Viral serology (IgM and IgG)
d. Biopsy
B
Page 3005. The gold standard for diagnosis of HCMV infection is viral culture from blood using human fibroblasts. Because it takes days to several weeks to see the cytopathic effect in culture, culture has been supplanted by PCR for the diagnosis of active HCMV infection.
True about roseala infantum except
a. It is caused by the human herpes virus -6
b. HHV-6 transmission occurs via shared saliva and can readily be detected in the saliva of adults and children.
c. The fever lasts approximately 3 to 7 days and is followed by the characteristic rash of roseola in all cases
d. HHV-6 is associated with exanthema subitem, Rosai-Dorfman Disease, pityriasis rosea and drug-induced hypersensitivity syndrome.
C
Page 3008. The fever lasts approximately 3 to 7 days and followed by the characteristic rash of roseola in only 23% of cases
the most common cause of transient aplastic crisis in patients with chronic hemolytic anemias
Parvovirus B19
most common complication of intrauterine infection with B19
Nonimmune fetal hydrops
The chronic anemia of persistent B19 infection may be treated successfully with what medication?
IV immunoglobulin
T/F: Erythema infectiosum are no longer infectious by the time they develop the illness, control measures directed toward these individuals are not likely to be effective
True
also known as human herpesvirus 4
Epstein-Barr Virus
Infectious mononucleosis is characterized by the triad of
Fever, lymphadenopathy and pharyngitis
most common manifestation of EBV infection in adolescents and adults
Infectious mononucleosis also referred to as the “kissing disease”
Incubation period of infectious mononucleosis
30 - 50 days
T/F: EBV infection during pregnancy is not thought to be teratogenic
True
Eruptions also frequently occur when patients with infectious mononucleosis are treated with antibiotics, classically what antibiotic
ampicillin
In ampicillin rash, Beginning 7 to 10 days after the initiation of ampicillin, patients develop a generalized, pruritic, morbilliform rash with an erythematous or copper color that resolves in a week (Fig. 163-7). This eruption also has been reported with other antibiotics. What other antibiotics are associated with its occurrence
amoxicillin, cephalexin, erythromycin, and levofloxacin
The exanthem does not usually indicate a permanent allergy to the medication
EBV infection also has been implicated in the development of non–sexually related acute genital ulcers. What do you call these ulcers and where is the area of predilection?
Lipschütz ulcers
Lipschütz ulcers 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 minora.
Ulcers can also occur in males with involvement of the scrotum
EBV-associated genital ulcers are not recurrent and self-resolve in 2 to 6 weeks.
Gianotti-Crosti syndrome is associates with what virus
EBV
What lymphoma is strongly associated with EBV?
Nasal-type extranodal natural killer/T cell lymphoma (ENK/T)
Gianotti-Crosti Syndrome typically affects children between the ages of?
3 months and 15 years
Peak age of onset of gianotti-crosti syndrome
1 - 6 years
What two viruses are associated with gianotti-crosti syndrome?
Hepatitis B and EBV
Areas of predilection of gianotti-crosti syndrome
Face, extenso surface of extremitites and buttocks
Involvement of what areas of the body makes the diagnosis of GCS less likely?
trunk, palms, soles, or mucosal surfaces
the most common clinical picture associated with the parvovirus B19 virus
Fifth disease
antibodies that can be used to confirm an EBV infection
Heterophile antibody and EBV-specific antibodies
A heterophile antibody is an antibody that recognizes antigens on erythrocytes from a different species
heterophile antibody test frequently used to confirm infectious mononucleosis in adolescents and adults with classic symptoms because of its rapid turnaround time and high specificity in the appropriate clinical setting
monospot test
- antibodies against horse red blood cells produced in a person with an EBV infection
- may be negative in the first week of infection and is not a sensitive test for children younger than 4 years old
host risk factors associated with Gianotti-Crosti syndrome (GCS)
young age and a history of atopic dermatitis
most common trigger of GCS
Viral infections
most common accompanying symptom of GCS
Pruritus
also known as human herpesvirus 5.
Cytomegalovirus
most common congenital viral infection
Human cytomegalovirus (HCMV)
how is perinatal and congenital HCMV different from one another when it comes to manifestations?
Perinatal infection with HCMV is very different from congenital HCMV infection, and is without diffuse visceral or CNS involvement.
also known as heterophile-negative mononucleosis
HCMV mononucleosis
defined as CMV infection with these symptoms: viral syndrome with fever, malaise, leukopenia, and thrombocytopenia; or tissue invasive disease with variable pneumonitis, enteritis, hepatitis, retinitis, and CNS disease
CMV disease
CMV infection is defined as evidence of CMV replication with or without disease symptoms.
gold standard for diagnosis of HCMV infection
viral culture from blood using human fibroblasts
diagnosis of congenital HCMV infection can be made by what ancillary
detection of virus in urine or saliva via PCR
most reliable method to determine past infection of HCMV and is used as part of pretransplantation screening
HCMV serology (IgG)
The most widely used test for diagnosis, and monitoring response to treatment in immunocompromised patients with CMV
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) are seen in small dermal vessels
Medications that have been approved for systemic treatment of HCMV disease
Ganciclovir, valacyclovir, foscarnet, and cidofovir
this drug improves hearing and neurodevelopmental outcomes in patients with symptomatic congenital HCMV infection
Oral valganciclovir for 6 months
Diseases caused by HHV 6
- Exanthem subitum (roseola infantum, sixth disease)
- Pityriasis rosea
- Rosai-Dorfman Disease
- Drug-induced Hypersensitivity Syndrome
HHV-6 is a member of the β-Herpesviridae subfamily and exists as 2 distinct species: HHV-6a and HHV-6b.
What causes exanthem subitum?
HHV-6b
- reactivates in immunocompromised hosts
HHV-6 preferentially infects what cells?
activated CD4+ T lymphocytes
cellular receptor for HHV-6 infection
CD46
mode of transmission of HHV-6
HHV-6 transmission occurs via shared saliva
incubation period for HHV-6 infection
**5 to 15 days, **with an average of 10 days.
hallmark of exanthem subitum
development of “rose”-colored macules and papules measuring 2 to 5 mm and surrounded by a white halo
The exanthem lasts 3 to 5 days and is widespread spread on the neck and trunk, and occasionally occurs on the face and proximal extremities.
unique feature of exanthem subitum
rash presents 1 day before to 1 to 2 days after the fever resolves
- as opposed to most viral exanthems where eruptions occur at the onset of the illness.
- “rose”-colored macules and papules measuring 2 to 5 mm and surrounded by a white halo
Children with this viral exanthem may have **palpebral edema **resulting in a “sleepy” appearance and erythematous papules on the soft palate **(Nagayama spots) **that may precede the viral exanthem.
Exanthem subitum/ roseola infantum
Pityriasis rosea may by be associated with what viruses?
HHV 6 and 7
The most common complication of a primary infection of HHV-6
febrile seizure
CD46 is the cellular receptor for what viral infection?
HHV-6
Rosai-Dorfman Disease is associated with what viral infection?
HHV-6
The reactivation of this viral infection is well-described i drug hypersensitivity reactions
HHV-6
Exanthem subitum/ roseola infantum is associated with what viral infections?
HHV-6 and 7
difference in manifestation of HHV 6 and 7 primary infection
Primary infection of HHV-7 occurs during childhood, but later than, and at a slower rate than, infection with HHV-6.
When HHV-7 is associated, ES tends to occur later in life than when HHV-6 is associated.
The rash associated with HHV-7 is lighter in color and occurs later in the course of the disease than HHV-6–associated ES
HHV associated with lichen planus
HHV-7
Diagnosis of active HHV-7 infection by PCR can only be made from acellular material such as what specimen?
CSF, serum, or plasma, because the virus is latent in peripheral blood mononuclear cells and tissue
Hand-foot-mouth disease is caused by what enteroviruses?
coxsackievirus A16 and enterovirus 71
mode of transmission of HFMD
Viral transmission is via the **fecal–oral route **and, less commonly, respiratory inhalation.
hallmark of HFMD
development of a vesicular eruption on the palms and soles
- The lesions start as bright pink macules and papules that progress to small 4- to 8-mm vesicles with surrounding erythema.
- Vesicles quickly erode and form yellow to gray, oval or “football-shaped” erosions surrounded by an erythematous halo.
- Cutaneous vesicles are found on the palms, soles, sides of hands and feet, buttocks and, occasionally, external genitalia.
nail finding that has occasionally been reported as a consequence of coxsackievirus A16 and enterovirus 71 infections.
onychomadesis
The most common serious complication associated with HFMD
aseptic meningitis
- important cause of HFMD outbreaks in Asia, is associated with severe illness
enterovirus 71
- Epidemics of enterovirus 71 are associated with severe neurologic disease, including encephalitis, encephalomyelitis, and polio-like syndromes.
- Enterovirus 71 infection may also lead to myocarditis, pulmonary edema, pulmonary hemorrhage, and death.
virus associated with ATYPICAL HFMD
COXSACKIEVIRUS A6
a defining feature in classic HFMD found in nearly 100% of patients and are seen less frequently in CVA6 infection
Oral ulcerations
Virus associated with eczema coxackium
coxsackievirus A6
- Clinical features more suggestive of eczema coxsackium include concurrent oral aphthae, palmoplantar macules and vesicles, perioral involvement, the lack of herpetiform grouping of vesicles, and the onset occurring the context of family or community outbreak.
- The CVA6 exanthem generally resolves in 1 to 2 weeks.
The 2 most common complications of coxsackievirus A6
- desquamation of the hands and feet
- onychomadesis
- typically occurs in children between 1 and 5 years of age
- slight female predominance,
- 1- to 2-mm, pinpoint, pruritic, pink papules with a surrounding pale halo localized to a large flexural region like the axillae or groin
- papules then spread centrifugally
- can become bilateral and more widespread within 5 to 15 days, but a unilateral and asymmetric distribution remains
- a preceding viral syndrome consisting of mild upper respiratory tract, low-grade fever, or GI tract symptoms can often be elicited.
- In the area of the eruption, enlargement of regional lymph nodes are frequently identified.
Unilateral laterothoracic exanthem is also called asymmetric periflexural exanthem of childhood.
- small, 2- to 4-mm, red papules that resembled angiomas on the face and extremities
- The papules** blanched on pressure **and were surrounded by a **small, 1- to 2-mm, halo. **
- The eruption was short lived and typically resolved within 10 days
- Patients often had associated fever, malaise, headache, diarrhea, and respiratory complaints.
ERUPTIVE PSEUDOANGIOMATOSIS
