A Woman with Fever, Malaise, Myalgias and Rash

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White Islands in a Sea of Red

Presented by Dr Henry B.B. Foong

from Foong Skin Specialist Clinic

Ipoh, Malaysia

A 45-year-old woman presented with a one-week history of fever and generalised rash. She initially had fever and sore throat and subsequently developed shoulder myalgia.  She saw her general practitioner who prescribed antihistamines and analgesics.  She then developed rashes on the legs.  Thinking this could be a drug eruption, the patient consulted her general practitioner again who did not think this was a cutaneous drug eruption.  Instead, he prescribed amoxicillin/clavulanate, but the rash spread further to her trunk and upper limbs.  The rash was only mildly pruritic.  She had no eye, oral or genital symptoms. There was no history of contact with patients with similar illness.

Physical examination showed stable vital signs with no dehydration. There was generalized confluent erythema distributed mainly on the legs but extending to trunk and upper extremities.  Prominent “islands of white” within the erythema over the lower legs were noted. It did not blanch completely, leaving behind petechiael lesions when pressed.

Clinical Photographs

Lab: Blood tests were positive for Dengue IgG and IgM antibody.

TWBC 5,100 (N38% L 36% M 22% E3% B1%) platelets 71,000 and Hct 38%

Pathology: 2 skin biopsies were taken from the right leg. One from the confluent generalised erythema and another from the white islands. Histopathology is pending

Diagnosis: Exanthem of Dengue Fever

Discussion

Dengue Fever ranks among one of the most important arthropod borne viral infections with high morbidity and mortality in the tropics and subtropics including urban populations. It is caused by Dengue virus, a flavivirus which is transmitted by mosquitos Aedes aegypti and Aedes albopictus.  There are 4 distinct serotypes DENV-1,2,3 and 4. Each episode of infection induces a life-long protective immunity to the homologous serotype but confers only  partial  and  transient  protection  against  other  serotypes.

The cutaneous manifestations of dengue fever are characteristic.  Skin eruptions appear in 80% of patients during the remission of the fever. Approximately one-half of patients develop a centrifugal macular, maculopapular, scarlatiniform, or petechial eruption. The cutaneous eruptions may become confluent, with small, round islands of sparing, the so-called white islands in a sea of red. The rash characteristically starts on the dorsum of the hands and feet and spreads to the arms, legs, and torso; the face is rarely involved. The eruption seen in dengue is usually short-lived, lasting from a few hours to several days.

Reference:

eMedicine:  Dermatologic Manifestations of Dengue.

from eMedicine reference