What is this Rash? (Part 1)

Have you ever undressed your child at bath time, just to discover a red rash all over their back / arms and legs? Or thought that they were injured because of the linear or circular red rash over their hand or face? All children will have some sort of rash at some point in their lives, and it must be the problem that moms have asked me the most questions about via Whatsapp! I called on the expertise of two dear dermatology friends to help us understand the red rash better:

Did you know the skin is the biggest organ in your body? Like the heart, lungs and kidneys it has its own complex working and consists of many layers. It has many functions and even its own microbiome! Because it is so exposed to the elements from the outside, and to everything circling in our blood on the inside, it is easy for something to go wrong, and this often presents as a red rash.

“What comfort there is in the skin of someone you love!” 

Erich Maria Remarque, The Night in Lisbon

Dr Knight explains that some rashes are formed by the direct irritation of the outer skin cells (keratinocytes), or by inflammation and increased blood flow to a region of the skin.  There may be an increase in fluids in the deeper layers, too many new skin cells produced or even cell death due to some drug-reactions.

To give us some more clues on the causes of a red rash, Dr van der Walt explains that we have to look at the shape, colour, pattern and consistency of the lesions. Dr Knight also wants to know “when the rash started, where about on the body did it start and spread to, what did the first lesion look like and has it changed at all, are there any accompanying symptoms (fever, itching, nausea, vomiting), is anyone else at home etc affected and has the child been given any new medication or have any recent exposures?”

Red rashes can be classified into:

Infectious  rashes                                                      Non-infectious rashes

-Viral                                                                                -Inflammatory eg eczema

-Bacterial                                                                        -Allergy / Urticaria

-Fungal                                                                            -Chemical/plant based irritants

-Protozoal (parasitic)                                                    -Drug reactions

                                                                                          -Auto-immune diseases

Determining the cause of the rash can be tricky with many having overlapping features and not all rashes presenting typically in all children. Parents should be encouraged to not try diagnosing rashes based on Google as even us professionals sometimes have trouble determining the cause. Apart from a few very specific shapes and sizes, it is almost impossible to diagnose the cause of a rash by looking at a single photo.

Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own.

Matthew 6:34

So when should you worry?

Any rash with systemic symptoms, like fever, or if the child is not feeding/drinking well, should be given immediate medical attention.

According to Dr Knight, Red flags to look out for will be:

> high fever
> painful rash
> rashes that spread rapidly
> rashes in young infants
> associated dizziness or fainting
> lip swelling, throat swelling +/ difficulty breathing
> rashes that start within a few hours after taking medication or food

Dr van der Walt adds if the rash does not respond to home remedies or causes discomfort to the child one should also seek medical care rather sooner than later.

Some tips on basic home management from Drs Knight and Van der Walt:

• Ensure lots of rest and fluids.
• Avoid soap/bubble bath and washing/scrubbing too much if the child’s skin is dry or itchy.
• Control temperature avoiding fever. (See my post on fever here.) Warm clothes / too many blankets / warm water can also further irritate the skin.
• Apply a plain cetomacrogol containing cream/emollient to the skin (cream can also be used as a soap replacement). Epimax and Epiderm are both excellent products and can be used from the newborn stage.
• If the rash is in the area of the buttocks, let baby’s bum get some air, change nappies regularly and use a zinc-containing bum cream or any other good barrier cream to help create a barrier between the skin and the irritants (aka urine and nappy-chemicals).
• Topical corticosteroid creams are only effective in eczema and drug reactions but are occasionally used to offer symptomatic support. (Should be used with caution as it can cause the skin to become very thin and have a low resistance to infections)
• Lotions such as calamine can be used to soothe the skin along with systemic antihistamines which have a sedative effect and is only used in urticaria/ severe eczema.

Dr van der Walt ends with the reminder to rather consult a doctor if there is any uncertainty and be careful of relying on a picture to make a diagnosis as this can be very misleading.

I hope this introduction to red rashes could set your mind at ease and give some practical advice. In my next post we can tackle a few of the most common infective causes together and look at when (and for how long) you should keep your child at home with a rash.

*** Dr Jonita van der Walt is a qualified Dermatologist and is also a dedicated mommy to almost-two-year-old Ilezé.

***Dr Lauren Knight is a Registrar in Dermatology and also runs a great Instagram-page @derm.discovered where she demystifies the skin for us.