4 y/o with low-grade fever, rash on cheeks x 24h now spreading to the trunk
Patient will present as → a 4-year-old who is brought to the office by his mother. The child has had a low-grade fever, headache, and sore throat for the past week. Four days ago, he suddenly developed a bright red rash on his cheeks, which, during the past two days, has spread to the trunk, arms, and legs. On physical examination, the child has erythema of the cheeks and a maculopapular rash with central clearing on the trunk spreading to the extremities. There are no other significant findings.
Erythema infectiosum (also known as Fifth's disease) is a common viral exanthem observed in pediatric patients caused by parvovirus B19
- Viral prodrome sequence with low-grade fever followed by slapped cheek malar rash on face and circumoral pallor for 2-4 days, followed by lacy, reticular rash (blanching) on extremities for a few weeks
- Parvovirus may cause aplastic crisis in patients with sickle cell disease and G6PD deficiency
Diagnosis is based primarily on clinical observations, history, and physical exam
- Serology: associated with enlarged nuclei with peripherally displaced chromatin
- PARVO B19-specific IgM antibodies and PCR
View more images of erythema infectiosum
Observation alone
- Treatment is symptomatic
- The rash may last a few days to several weeks. It is frequently pruritic
- There is no specific antiviral used and no vaccine is available
- Parvovirus B19 is a droplet infection that is no longer contagious once the rash breaks out. Children may return to school and resume activities as symptoms allow.
Osmosis | |
(Erythema infectiosum lecture begins at 1:15) |
Erythema infectiosum or Fifth’s Disease is a mild viral infection that is characterized by the slapped face appearance. It typically occurs in school-age children; however, adults can contract the disease. Pain and swelling in the joints (polyarthropathy syndrome) is a common finding in adult women with the disease. It is transmitted by respiratory secretions, blood, and blood products. The period of communicability is uncertain and the incubation period is 4 to 14 days and may be as long as 21 days. Isolation is not necessary.
Play Video + QuizQuestion 1 |
Staphylococcus aureus Hint: Staphylococcus aureus can cause various skin infections, such as impetigo, cellulitis, and abscesses, but it is not associated with erythema infectiosum. The presentation of a "slapped cheek" rash and lacy, reticular rash on the extremities is not typical for infections caused by Staphylococcus aureus. | |
Parvovirus-B19 | |
Herpes simplex virus Hint: Herpes simplex virus typically causes oral or genital lesions, known as cold sores or genital herpes, respectively. It does not cause the "slapped cheek" appearance or the lacy rash seen in erythema infectiosum. | |
Cytomegalovirus Hint: Cytomegalovirus (CMV) can cause a mononucleosis-like syndrome, particularly in immunocompromised individuals, but it does not typically present with the distinct rash seen in erythema infectiosum. CMV infections are more commonly associated with symptoms like fever, fatigue, and hepatosplenomegaly. | |
Rubella virus Hint: Rubella virus causes German measles, which can present with a rash and fever. However, the rash in rubella is different from the "slapped cheek" appearance of erythema infectiosum. Rubella rash typically starts on the face and spreads downwards and is accompanied by other symptoms like lymphadenopathy and arthralgia. |
Question 2 |
IgG and IgM antibody testing Hint: IgG and IgM antibody testing may confirm parvovirus B19 infection but is unnecessary given the classic exam findings. | |
Complete blood count Hint: Complete blood count should be checked in immunocompromised children to rule out transient aplastic crisis but not in healthy patients. | |
Viral polymerase chain reaction (PCR) Hint: Viral PCR testing is used to detect viremia in high-risk groups if needed but not routine. | |
No further laboratory testing | |
Bone marrow examination Hint: Bone marrow examination is unnecessary as features are consistent with a benign viral illness without cytopenias. |
Question 3 |
Oral Acyclovir Hint: This antiviral medication is effective against herpesviruses but not against Parvovirus B19, which causes Erythema Infectiosum | |
Intravenous Immunoglobulin (IVIG) Hint: IVIG is used in severe cases of Parvovirus B19 infection, such as in immunocompromised patients or those with chronic hemolytic anemias who develop aplastic crises. In a healthy child with typical Erythema Infectiosum, IVIG is not indicated. | |
Supportive care with antipyretics and antihistamines | |
Oral Amoxicillin Hint: Amoxicillin is an antibiotic and has no role in the treatment of Erythema Infectiosum, which is caused by a virus. Antibiotics are not effective against viral infections and their misuse can contribute to antibiotic resistance. | |
Topical Corticosteroids Hint: Amoxicillin is an antibiotic and has no role in the treatment of Erythema Infectiosum, which is caused by a virus. Antibiotics are not effective against viral infections and their misuse can contribute to antibiotic resistance. |
List |
References: Merck Manual · UpToDate