Exa

Exanthem
Rash.jpg
Synonyms	Rash
Pronounce	N/A
Specialty	N/A
Symptoms	Red, inflamed skin, often with spots or bumps
Complications	Infection, scarring
Onset	Sudden
Duration	Varies
Types	N/A
Causes	Viral infection, bacterial infection, drug reaction
Risks	N/A
Diagnosis	N/A
Differential diagnosis	N/A
Prevention	N/A
Treatment	Depends on cause
Medication	N/A
Prognosis	N/A
Frequency	N/A
Deaths	N/A

Overview

An exanthem is a widespread rash that usually occurs in children. It is often associated with systemic symptoms such as fever, malaise, and headache. Exanthems can be caused by a variety of factors, including viral infections, bacterial infections, and drug reactions.

Etiology

Exanthems are typically classified based on their underlying cause:

Viral Exanthems

Viral exanthems are the most common type and are often seen in childhood illnesses. Common viral causes include:

• Measles
• Rubella
• Varicella (chickenpox)
• Roseola
• Erythema infectiosum (fifth disease)

Bacterial Exanthems

Bacterial infections can also lead to exanthems, though they are less common than viral causes. Examples include:

• Scarlet fever, caused by Streptococcus pyogenes
• Toxic shock syndrome, associated with Staphylococcus aureus or Streptococcus pyogenes

Drug-Induced Exanthems

Certain medications can cause exanthems as a side effect. These are often referred to as drug eruptions and can be caused by:

• Antibiotics such as penicillin
• Nonsteroidal anti-inflammatory drugs (NSAIDs)
• Anticonvulsants

Clinical Presentation

Exanthems typically present as a diffuse rash that may be macular, papular, or vesicular. The rash often starts on the face and spreads to the trunk and limbs. Accompanying symptoms may include:

• Fever
• Lymphadenopathy
• Conjunctivitis
• Cough

Diagnosis

The diagnosis of an exanthem is primarily clinical, based on the appearance of the rash and associated symptoms. A thorough history and physical examination are essential. Laboratory tests may be used to confirm the diagnosis, including:

• Serology for specific viral antibodies
• Throat culture for bacterial causes
• Skin biopsy in atypical cases

Management

Treatment of exanthems depends on the underlying cause:

Viral Exanthems

Most viral exanthems are self-limiting and require only supportive care, such as:

• Antipyretics for fever
• Hydration
• Rest

Bacterial Exanthems

Bacterial exanthems require appropriate antibiotic therapy. For example, penicillin is used to treat scarlet fever.

Drug-Induced Exanthems

The primary treatment is discontinuation of the offending drug. Symptomatic relief can be provided with:

• Antihistamines for itching
• Topical corticosteroids

Prognosis

The prognosis for exanthems is generally good, especially for viral causes, which are usually self-limiting. Complications are rare but can include:

• Secondary bacterial infection
• Scarring

Prevention

Preventive measures depend on the cause of the exanthem:

• Vaccination for preventable viral infections such as measles and rubella
• Avoidance of known drug allergens

See Also

• Dermatitis
• Urticaria
• Eczema

External Links

• American Academy of Dermatology: Rashes

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