A red rash in children is a common condition characterized by redness, irritation, and sometimes other skin symptoms. The incidence of red rashes in children is quite high, with most children experiencing at least one episode before 2 years of age. This condition is important because it can be caused by a wide range of underlying factors, some benign and others more serious. Recognizing the type and cause of a rash is essential to direct management and prevent complications.
Types of rashes
Rashes in children can vary widely in appearance, location, and associated symptoms. Some rashes are flat and red, while others may be raised, blistered, or accompanied by scaling. The importance of recognizing the type of rash lies in its diagnostic value. Different rashes are associated with different conditions, and identifying the type can guide healthcare providers toward an accurate diagnosis and appropriate treatment. For example, a viral exanthem presents differently than eczema, which in turn differs from a bacterial infection like impetigo.
Helpful definitions
Here are some definitions for terms commonly used when describing rashes in children (and adults):
- Blister: A raised area on the skin filled with clear fluid.
- Scaling: Flaky or scaly patches of skin.
- Crust: Dried blood, pus, or other fluid on the skin surface, forming a scab.
- Vesicles: Small, fluid-filled blisters.
- Macules: Flat, distinct, discolored areas of skin.
- Papules: Small, raised bumps on the skin.
- Purpura: Larger purple or red spots on the skin caused by bleeding underneath.
- Petechiae: Small red or purple spots on the skin caused by minor bleeding.
- Blanching: When pressed, the redness of the rash fades.
- Non-blanching: When pressed, the redness does not fade.
- Lacy: A rash with a pattern that looks like lace.
- Mucosa: The moist tissue lining some organs and body cavities, such as the mouth and nose.
- Patches: Larger areas of flat, discolored skin.
- Plaques: Large, raised, flat-topped areas of skin.
What is the most common cause of a red rash in children?
Viral exanthem
One of the most common causes of a red rash in children is viral exanthem, a rash caused by viral infections. Viral exanthems are prevalent, particularly in young children, and can occur with infections such as measles, rubella, roseola, and parvovirus B19. The pathogenesis involves the immune response to the viral infection, which results in inflammation and rash. These rashes typically affect children aged six months to five years. They often present with a sudden onset of red spots or patches that may spread across the body. Additional symptoms can include fever, malaise, and upper respiratory symptoms. Diagnostic clues include a history of recent illness and characteristic rash patterns. Examination will show a maculopapular rash with varying distribution based on the specific viral infection. Treatment is generally supportive, focusing on symptom relief, as these rashes usually resolve on their own.
Other common medical conditions associated with a red rash in children
Eczema (atopic dermatitis)
Eczema is a chronic inflammatory skin condition that commonly affects children. It often appears as red, itchy patches on the face, elbows, and knees. Distinguishing features include a personal or family history of atopic conditions, dry skin, and a relapsing-remitting course. Examination will show erythematous (red), scaly, and possibly lichenified (thickened) plaques, often with excoriations (scratch marks). Treatment includes moisturizing the skin, avoiding triggers, and using topical corticosteroids.
Impetigo
Impetigo is a bacterial infection caused by Staphylococcus aureus or Streptococcus pyogenes. It presents with red sores that quickly rupture, ooze and form a yellow-brown crust. It commonly affects the face and extremities. Examination will show honey-colored crusted lesions, often around the mouth and nose. Diagnosis is based on clinical appearance and bacterial cultures. Treatment involves topical or oral antibiotics.
Contact dermatitis
Contact dermatitis results from direct skin contact with an irritant or allergen. It presents as red, inflamed areas that may blister or become crusty. A key diagnostic clue is the rash’s distribution, often localized to areas of contact with the offending substance. Examination will show well-demarcated, erythematous patches or plaques with or without vesicles or bullae. Treatment includes avoiding the irritant and using topical steroids.
Scarlet fever
Scarlet fever is caused by Streptococcus pyogenes. It presents with a red, sandpaper-like rash, typically following a sore throat. The rash usually starts on the chest and spreads. Examination will show a diffuse, erythematous rash with a rough texture, often accompanied by “strawberry tongue” and Pastia’s lines (red streaks in skin folds). Diagnosis is confirmed with a throat culture or rapid strep test. Treatment includes antibiotics.
Chickenpox (varicella)
Chickenpox presents with an itchy red rash that progresses to fluid-filled blisters and then scabs. It typically starts on the trunk and spreads outward. Examination will show lesions in various stages of development, including macules, papules, vesicles, and crusted scabs. Diagnosis is clinical, supported by a history of exposure. Treatment includes symptom relief and antiviral medications for severe cases.
Hand, foot, and mouth disease
The virus coxsackievirus causes hand, foot, and mouth disease and presents with a red rash that typically (but not always) involves the hands, feet, and mouth, often with painful blisters. Examination will show erythematous macules and papules on the palms, soles, and oral mucosa, which may develop into vesicles. Diagnosis is clinical, based on the characteristic rash and associated fever. Treatment is supportive.
Fifth disease (erythema infectiosum)
Fifth disease is caused by infection with parvovirus B19 and presents with a “slapped cheek” red rash on the face and a lacy red rash on the body. Examination will show bright red erythema on the cheeks and a reticular rash on the trunk and extremities. The diagnosis is clinical and supported by serology. Treatment is supportive.
Roseola
Roseola is a viral infection that causes a sudden high fever followed by a red rash as the fever subsides. It typically affects children under two years. Examination will show a maculopapular rash that starts on the trunk and spreads to the neck and extremities. Diagnosis is clinical, based on the characteristic fever and rash sequence. Treatment is supportive.
Measles
Measles presents with a red, blotchy rash that starts on the face and spreads downward. It is accompanied by fever, cough, and Koplik spots in the mouth. Examination will show a maculopapular rash that starts at the hairline and moves down the body, along with small white spots on the buccal mucosa. Diagnosis is clinical, confirmed by serology. Treatment is supportive, with an emphasis on preventing complications.
Rubella
Rubella causes a red rash that starts on the face and spreads. It is milder than measles and accompanied by mild fever and lymphadenopathy. Examination will show a fine, pink maculopapular rash that begins on the face and spreads to the trunk and limbs, along with postauricular and occipital lymphadenopathy. Diagnosis is clinical, confirmed by serology. Treatment is supportive.
Hives (urticaria)
Hives are raised, itchy welts on the skin that can be triggered by allergic reactions, infections, or other factors. Examination will show transient, erythematous, and edematous plaques that blanch with pressure. Diagnosis is clinical, based on history and physical examination. Treatment includes antihistamines and avoiding triggers.
Heat rash (miliaria)
Heat rash occurs when sweat ducts become blocked, and sweat is trapped under the skin. It presents with small, red bumps, often in skin folds or areas where clothing causes friction. Examination will show tiny, clear, or red papules in a cluster. The diagnosis is clinical, based on the appearance and recent heat exposure. Treatment includes keeping the skin cool and dry.
Diaper rash (diaper dermatitis)
Diaper rash is an irritation of the skin covered by a diaper. It presents as red, inflamed skin, sometimes with blisters or pustules. Examination will show erythema and scaling in the diaper area, possibly with satellite lesions if a secondary yeast infection is present. The diagnosis is clinical. Treatment includes frequent diaper changes, barrier creams, and antifungal creams if necessary.
Erythema toxicum
Erythema toxicum is a common, benign rash seen in newborns. It presents as red macules and papules that can become pustules. Examination will show erythematous macules with central pustules, often on the face and trunk. Diagnosis is clinical, based on appearance and age. Treatment is not necessary as the rash resolves spontaneously.
Molluscum contagiosum
Molluscum contagiosum is a viral infection that causes small, flesh-colored, or pink, dome-shaped papules with a central umbilication. Examination will show these characteristic lesions, often clustered in groups. Diagnosis is clinical. Treatment is usually not necessary as the lesions resolve on their own, but options include topical treatments or physical removal.
Scabies
The mite Sarcoptes scabiei causes scabies and presents with intense itching and a red rash. Examination will show small, erythematous papules and burrows, especially in web spaces of the fingers, wrists, and axillae. Diagnosis is clinical, supported by skin scraping. Treatment includes topical scabicides.
Less common but serious medical conditions associated with a red rash in children
Kawasaki disease
Kawasaki disease is a type of vasculitis that causes a red rash, fever, and swelling of the hands and feet. If untreated, it can lead to coronary artery aneurysms. The examination will show a polymorphous rash, conjunctival injection, erythema and edema of the hands and feet, and oral changes like a strawberry tongue. The diagnosis is clinical and supported by echocardiography. Treatment includes intravenous immunoglobulin and aspirin.
Meningococcemia
Meningococcemia is a bacterial infection that causes a petechial or purpuric rash and can be life-threatening. It often starts with fever and nonspecific symptoms and progresses rapidly. Examination will show petechiae or purpura, often accompanied by signs of sepsis such as hypotension and altered mental status. Blood cultures confirm the diagnosis. Treatment includes urgent antibiotics.
Rocky Mountain spotted fever
Rocky Mountain spotted fever is a tick-borne illness caused by Rickettsia rickettsia. It presents with a rash that starts on the wrists and ankles and spreads centrally. Examination will show a maculopapular rash that becomes petechial, often accompanied by fever, headache, and myalgia. The diagnosis is clinical and confirmed by serology. Treatment includes doxycycline.
Stevens-Johnson syndrome
Stevens-Johnson syndrome is a severe hypersensitivity reaction that causes a red rash with blistering and mucosal involvement. It can be life-threatening and requires hospitalization. The examination will show target lesions or widespread erythema with blistering, along with the involvement of at least two mucosal sites. Diagnosis is clinical, supported by skin biopsy. Treatment includes stopping the offending drug and supportive care.
Toxic shock syndrome
Toxin-producing bacteria cause toxic shock syndrome. It presents with a red, sunburn-like rash and systemic symptoms like fever and hypotension. Examination will show diffuse erythema that desquamates, along with signs of multi-organ involvement. The diagnosis is clinical and confirmed by cultures. Treatment includes antibiotics and supportive care.
Systemic lupus erythematosus
Systemic lupus erythematosus is an autoimmune disease that can cause a red, butterfly-shaped rash on the face. Systemic symptoms like joint pain and fatigue accompany it. Examination will show a malar rash that spares the nasolabial folds, along with other signs like oral ulcers and arthritis. Diagnosis is clinical, supported by serology. Treatment includes immunosuppressants.
Henoch-Schönlein purpura
Henoch-Schönlein purpura is a type of vasculitis that causes a purpuric rash on the legs and buttocks, along with abdominal pain and joint pain. Examination will show palpable purpura without thrombocytopenia, often on the lower extremities and buttocks. Diagnosis is clinical, supported by biopsy. Treatment is supportive.
Juvenile idiopathic arthritis
Juvenile idiopathic arthritis is an autoimmune condition that can cause a red rash and joint inflammation. Examination will show an erythematous, maculopapular rash associated with fever and arthritis in one or more joints. The diagnosis is clinical and supported by serology. Treatment includes anti-inflammatory medications.
Infective endocarditis
Infective endocarditis is an infection of the heart valves. It can cause a red rash and systemic symptoms. Examination may show Janeway lesions (painless erythematous spots on the palms and soles), Osler nodes (painful nodules on the fingers and toes), and Roth spots (retinal hemorrhages). Diagnosis is confirmed by blood cultures and echocardiography. Treatment includes antibiotics and sometimes surgery.
Sepsis
Sepsis is a life-threatening response to infection, and that can cause a red rash and systemic symptoms like fever and hypotension. Examination will show signs of systemic inflammation, including erythema, petechiae, or purpura, along with signs of organ dysfunction. The diagnosis is clinical and supported by cultures. Treatment includes antibiotics and supportive care.
Clues that aid in the differential diagnosis
- Itchiness: Often associated with conditions like eczema, contact dermatitis, and chickenpox. Examination will show excoriated, erythematous patches or vesicles.
- Pain: May suggest bacterial infections like impetigo or conditions like Stevens-Johnson syndrome. Examination will reveal tender, inflamed areas or blistering lesions.
- Swelling: Can be seen in conditions like Kawasaki disease or Henoch-Schönlein purpura. Examination will show edematous, erythematous skin, often with purpura.
- Fever: It is common in viral exanthems, scarlet fever, and serious conditions like meningococcemia and sepsis. Examination will reveal a febrile child with signs of systemic infection.
- Cough: This may indicate viral infections like measles or rubella. Examination will find a child with upper respiratory symptoms and a characteristic rash.
- Difficulty breathing: A serious symptom that can occur in conditions like anaphylaxis or toxic shock syndrome. Examination will show signs of respiratory distress, such as wheezing or stridor, along with a diffuse erythematous rash.
- Location of rash: Specific locations can help differentiate conditions. For example, diaper rash is localized to the diaper area, while hand, foot, and mouth disease affects the palms, soles, and mouth.
- Appearance of rash: Different appearances aid diagnosis. For example, hives are raised and blanch with pressure, while petechiae and purpura do not blanch and suggest a more serious underlying condition.
- Onset and progression: Rapid onset may suggest an allergic reaction or infection like chickenpox, while a gradual onset is more typical of eczema or psoriasis.
Rash in an unvaccinated child
The following conditions need to be considered in an unvaccinated child with a red rash:
- Measles: Measles presents with a high fever, cough, coryza (runny nose), and conjunctivitis, followed by a characteristic maculopapular rash that starts on the face and spreads downward. Koplik spots, small white lesions inside the mouth, are also diagnostic. The diagnosis is clinical and confirmed by serology. Treatment is supportive, with a focus on preventing complications.
- Rubella: Rubella causes a mild fever, lymphadenopathy, and a fine, pink maculopapular rash that begins on the face and spreads to the trunk and limbs. The rash typically lasts three days. The diagnosis is clinical and confirmed by serology. Treatment is supportive.
- Varicella (chickenpox): Chickenpox presents with a pruritic rash that progresses from macules to papules to vesicles and then scabs. It usually starts on the trunk and spreads to the face and extremities. The diagnosis is clinical, based on the characteristic rash and history of exposure. Treatment includes symptom relief and antiviral medications for severe cases.
- Mumps: Mumps typically causes parotitis (swelling of the parotid glands), fever, and headache. It can also cause a non-specific rash. The diagnosis is clinical and confirmed by serology or PCR. Treatment is supportive.
- Pertussis (whooping cough): Pertussis causes severe coughing fits followed by a “whooping” sound during inhalation. The cough can be so severe that it causes petechiae or purpura due to increased intrathoracic pressure. Diagnosis is clinical, confirmed by PCR or culture. Treatment includes antibiotics.
- Diphtheria: Diphtheria can cause a skin infection with non-healing ulcers and a grayish membrane on the tonsils and pharynx. The diagnosis is clinical and confirmed by culture. Treatment includes antitoxin and antibiotics.
Advice for parents
Parents should seek medical attention if a child has a red rash accompanied by symptoms like fever, pain, swelling, and difficulty breathing or if the rash is widespread or persistent. Early evaluation by a healthcare provider can ensure appropriate diagnosis and treatment. Most red rashes in children are self-limited and can be managed with supportive care, such as hydration, rest, and topical treatments for itchiness or irritation. However, serious conditions require prompt medical intervention.
Summary
A red rash in children can have many causes, ranging from benign to serious. Recognizing the type of rash and associated symptoms is crucial for accurate diagnosis and treatment. Common causes include viral exanthems, eczema, and bacterial infections, while less common but serious causes include Kawasaki disease and meningococcemia. Parents should seek medical attention if concerning symptoms accompany a rash. Understanding the underlying cause of a rash ensures proper management and can prevent complications.