The need for a full medical team approach is necessary as the blueberry muffin rash can be indicative of a wide range of potentially serious diseases. Treatment and prognosis depend on the diagnostic findings and underlying cause.
The blueberry muffin rash is so named because the infant is born with multiple blue/purple marks or nodules on the skin. These nodules tend to appear on the head, neck and trunk of the body. The cutaneous manifestations (skin appearance) may include a petechial rash (round, pinpoint spots that appear in clusters) or a rash with maculopapular lesions (flat and raised lesions).
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Blueberry Muffin Rash Rubella
In the 1960s, America experienced an epidemic of rubella. Pediatricians reported a number of newborns born with magenta or reddish-blue lesions. The lesions were present at birth and appeared either within the first 48 hours or several months later. A definitive diagnosis was made depending on associated conditions. In the majority of cases, the lesions change to a tan color and disappear entirely within a few weeks. If the lesions do not fade within a few weeks or enlarge, a workup for a neoplastic disorder is in order .
The maculopapular rash was once believed to be a characteristic of congenital rubella. While this is still true, scientists have found it is sometimes linked to more dangerous conditions such cancers, blood disorders or other congenital infections.
Causes Of Blueberry Muffin Rash
A blueberry muffin rash indicates hematologic dyscrasia, commonly a blood abnormality or imbalance, that can be caused by various underlying conditions.
A number of hematologic disorders and hematologic factors can cause blueberry muffin lesions:
- Purpura (bleeding into the subcutaneous fat)
- Extramedullary erythropoiesis (presence of clusters of blood-producing cells in the skin)
- Malignancies (cancers)
- ABO Blood Group Incompatibility
- Epidermolysis Bullosa
Cancers that can cause this rash to include the following:
- Langerhans cell histiocytosis
- Congenital rhabdomyosarcoma
- Congenital leukemia cutis
Infections or viral disorders may also cause this rash:
- Congenital syphilis
- Herpes simplex
- Epstein Barr virus
- Varicella syndrome
- Congenital CMV infection
Blueberry Muffin Rash Concerns
Both prenatal care and post-natal care are essential to ensure a baby’s health. Any exposure to illnesses that can affect either the mother or the child should be reported. This includes exposure to rubella or chickenpox. Unusual lesions or rashes also warrant a call to the pediatrician.
Blueberry muffin rash rubella can appear as a neonatal eruption at birth. The characteristics of these eruptions appear as purple circular or oval macules, nodules or papules that reflect dermal erythropoiesis. These are typically seen as cutaneous manifestations.
Blueberry Muffin Rash Treatments To Consider
Parents who notice their infant develop a blueberry muffin rash rubella should seek treatment as soon as possible. Treatment is based on a correct diagnosis. Neonatal diagnostics may include a skin biopsy, bone marrow biopsy, exhaustive bloodwork and a complete physical exam including spleen and liver enlargement. When a pathologist checks a biopsy, various protein-based dyes are added to assess if specific proteins or hormones are present. If they are, they will react to the dye and change color. When checking a blueberry muffin rash, they are to looking to see if the tissue chemically reacts to a dye called “eosin.” During a reaction, the bright-pink dye stains both the cytoplasm and extracellular proteins. The proteins that react are called “eosinophilic” which when translated means “eosin loving .” Eosinophilic cytoplasm describes the cells that react. An infant will also be assessed for deafness due to sensorineural hearing loss and cataracts.
If a fetus is suspected of having a congenital condition, in-utero, maternal and prenatal care will be affected. An ultrasound will be used to assess head circumference for hydrocephalus or microcephaly. The fetus will also be assessed for slow intrauterine growth or abnormal development of the nervous system which may result in seizures.
When congenital infections cause lesions, antibiotic therapy is advised. Blood disorders may be treated with blood therapy.
While some blueberry muffin lesions may fade after a few weeks, if the lesions do not go away or increase in size or number, parents should immediately contact a pediatrician as this can be a sign of malignancies and subsequently a poor prognosis.
Babies have sensitive skin, and rash development is common. The majority of the time, these rashes are harmless. However, the skin can also provide early clues to more serious conditions, including malignancies. If you have any questions, never hesitate to contact your pediatrician.
Blueberry Muffin Rash Resources:  Indian Journal of Paediatric Dermatology; Blueberry muffin rash at birth due to congenital rubella syndrome, Guruprasada Shetty, Rashmi Kalyanshetti, Habeeb Ullah Khan, Pavan Hegde, 2013.
 UC Davis, Dermatology Online Journal; Blueberry muffin baby: A pictoral differential diagnosis, Mehta, VandanaBalachandran, CLonikar, Vrushali, 2008.
 Centers for Disease Control and Prevention; Rubella (German Measles, Three-Day Measles), September 15, 2017.