Introduction

Definition of intertrigo

Intertrigo, also known as sweat rash, is a skin condition that is fairly common and treatable but it can lead to infection when left untreated. It is known to happen in the folds of the skin where your skin rubs together. This friction causes inflammation on the skin, creating a red, bumpy rash.¹

Causes of intertrigo

Intertrigo is caused by friction in the skin and can be made worse with heat and moisture. It is more commonly found between the skin folds and between the fingers and toes. 

Trapped moisture, which is likely to be sweat, causes the surface of the skin to stick together. This then increases the friction between the skin, causing damage to the skin, growth of bacteria or fungi and inflammation. In many cases, the skin can break open, causing sweat and bacteria or fungi to enter the skin, creating an infection.^1,2

Different varieties of bacteria and fungi can cause secondary infections, including:

• Dermatophytes - fungi that need a protein called keratin to grow. Causes infection in nails and skin affecting fingers and toes
• Candida - this is a type of yeast and fungus
• Staphylococcus aureus - this bacterium is common for causing intertrigo bacterial infections

Symptoms of intertrigo

The symptoms of intertrigo depend on the severity and if there is an infection.^1,2,3

Early symptoms of intertrigo

Early symptoms of intertrigo without infection include:

• Itchiness or burning in the affected area
• Feeling uncomfortable
• Tender pain in the affected area
• Symmetrical red, brown rash with small bumps in the affected area 

Symptoms of untreated early-phase intertrigo

• Feeling like the affected skin in the affected area is raw
• Cracks in the skin
• Bleeding on the affected area
• Crusted/scaly skin in the affected area
• Blisters

Symptoms of intertrigo with an infection

• Foul smell in the affected area
• Pus containing bumps in the affected area
• Raised and tender bumps in the affected area

Diagnosis of intertrigo

Clinical examination

It can be difficult to diagnose intertrigo as it can look like other skin conditions. During your appointment, your doctor will conduct a visual examination of the skin and ask you questions such as

• History of any skin-related conditions
• Medication that you take
• Any allergies and sensitivities
• Products used on the skin 

If intertrigo is suspected, then your doctor can do certain tests that will help to diagnose you with intertrigo.^1,3

Microscopic examination

In order to diagnose intertrigo, your doctor will perform certain tests, including:

• Skin scraping - a tool is used to scrape or remove the affected area and this sample will then be examined under a microscope to understand the microorganism causing it
• Biopsy - This will then be examined under the microscope by a pathologist
• Wood’s lamp exam - small tool that uses black light to illuminate areas of the skin. If there is the presence of bacteria or fungi, the light in the affected area will be a different colour

Differential diagnosis

Other skin conditions may have similar presentations to intertrigo and can include:

• Seborrheic dermatitis
• Allergic contact dermatitis
• Atopic dermatitis
• Pemphigus
• Inverse psoriasis
• Scabies
• Metabolic derangements²

Complications of untreated intertrigo

In order to properly treat intertrigo, it is important to seek medical advice, to avoid potential complications such as:^1,2,3

• Cellulitis - deep skin infection caused by bacteria that  can be life-threatening
• Nail fungal infections 
• Sepsis 
• Contact dermatitis from the use of topical medications to treat rashes 

Management and treatment of intertrigo

One of the best ways to treat intertrigo in its early stages is by keeping the affected area cool, clean and dry.^3,4,5

If the condition worsens, be sure to contact your local GP.

Some ways to keep the intertrigo dry at home include:

• Drying yourself with a clean towel after taking a shower
• Wearing loose clothing and breathable fabrics such as  cotton
• Using a fan to cool down the affected area
• Use a mild deodorant in your armpits or under the breast area to decrease sweating or a powder agent like talcum powder
• Wearing a clean gauze or cotton to separate the affected area to help reduce friction

Treatment of intertrigo with infection

The treatment for intertrigo that is caused by an infection will require the aid of a doctor, to help in finding the cause, and decide the appropriate treatment. 

Treatment includes:

• Antibiotic cream - when the infection is caused by a bacteria, a specific topical antimicrobial cream is given. 
• Antifungal cream - when the infection is caused by a fungus, a topical antifungal cream will be given
• Oral medication - in more severe cases, oral medication such as antibiotics are given

Risk factors for intertrigo

Some of the risk factors for intertrigo include:^2,3,4

• Diabetes
• Excessive sweating 
• Excessive skin from weight loss
• Incontinence
• Obesity
• Age

Summary

Intertrigo is a skin condition that can be painful and unpleasant but it is generally very treatable and preventable. 

Keeping the affected area clean, dry and cool can prevent the condition from worsening.

If symptoms are not getting any better, your GP can assess you to diagnose and prescribe treatment that prevents infection.