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An Unbothersome Rash

  • Introduction. A 3 year-year-old previously healthy boy presents with a rash that abruptly appeared on his bilateral cheeks, upper arms, buttocks and extending slightly to his lower back and bilateral legs.

    History: Although the child is unbothered by the rash, he has had 3 days of cough, rhinorrhea, and sore throat. His father and sister were sick with a viral upper respiratory infection around 1 month ago, the family tested negative for COVID-19, and the patient’s mother denies the patient himself being sick at that time. Physical examination reveals a sick appearing child with unremarkable vital signs. He has bilateral erythematous 3+ tonsils with exudates, bilateral anterior and posterior cervical chain shotty lymphadenopathy, and nasal congestion. The rash is papular, mildly erythematous, and blanching on his bilateral cheeks, posterior upper arms, lower back, buttocks and bilateral legs. It spares the palms and soles. There are no areas of excoriation. (Figures 1-4).

    Fig. 1. Posterior right arm
    Fig. 1. Posterior right arm

    Fig. 2. Posterior left arm
    Fig. 2. Posterior left arm

    Fig. 3. Anterior trunk and thighs
    Fig. 3. Anterior trunk and thighs

    Fig. 4. Left cheek.
    Fig. 4. Left cheek.

    Diagnostic Testing: Rapid strep testing in office was negative and a strep culture was sent to the laboratory. Complete blood count with differential, C-reactive protein (CRP), basic metabolic panel, monospot, and Epstein-Barr Virus (EBV) titers were ordered and collected at by an outside laboratory. (Table 1).

    Table 1. Laboratory results

    Test

    Normal Range

    Patient Results

    White blood cell count

    5.0 - 16.0 thousand/uL

    12.4

    Red blood count

    3.90 - 5.50 million/uL

    4.19

    Hemoglobin

    11.5 - 14.0 g/dL

    11.5

    Hematocrit

    34.0 - 42.0 %

    35.8

    Platelet count

    140 - 400 thousand/uL

    274

    Neutrophils

    23 - 45 %

    18

    Lymphocytes

    35 - 65 %

    68

    Monocyte, absolute

    200 - 900 cells/uL

    1736/uL

    Monocytes

    4 - 10 %

    14

    Neutrophils, absolute

    1,500 - 8,500 cells/uL

    2,232

    Lymphocytes, absolute

    2,000 - 8,000 cells/uL

    8432/uL

    CRP

    <8.0 mg/L

    1.3

    EBV nuclear antigen antibody (IgG)

    > 21.99 U/mL

    < 18.00

    EBV early antigen D antibody

    (IgG)

    > 10.99 U/mL

    >150.00 (H)

    EBV capsid antigen (VCA) IgG antibody

    > 21.99 U/mL

    134.00 (H)

    EBV VCA IgM

    > 43.99 U/mL

    >160.00 (H)

    Heterophile, mononucleosis screening (REFL)

    Negative

    Negative