Introduction

Intertrigo, also known as Intertriginous dermatitis (ITD), is a common skin inflammation condition that affects the outer layer of skin. It often occurs in skin folds, and it happens due to skin-to-skin friction. It looks like a red hot bumpy rash.¹

Intertrigo can be found at any age, from early infancy to old age. It can be diagnosed in infants as a type of diaper dermatitis.1 According to a European systematic study of ITD in adults with the condition, it is estimated that the prevalence is 20% among home care recipients, 17% among nursing home residents, and 6% among hospital patients.²

In this article, we will review the causes, symptoms, diagnosis and available treatment options for intertrigo.

Causes and risk factors of intertrigo

The causes of intertrigo rely on 3 elements occurring simultaneously, including skin friction, trapped moisture and disturbing the skin barrier. 

As a multifactorial condition, several risk factors cause some people to be at greater risk of developing intertrigo, including:¹

• High-moisture environment: hot, humid weather plays a role by increasing sweating and creating an ideal environment for intertrigo to thrive¹
• Obesity: Overweight increases the number of wrinkles and folds on the skin and the regions where moisture can be trapped, which can enhance skin damage and inflammation³
• Genetic: Some people may be more susceptible to developing intertrigo if they have a hereditary susceptibility to specific skin disorders
• Hyperhidrosis (excessive sweating): Sweating causes the skin to stay wet and changes the skin environment, promoting the growth of bacteria and fungus that can cause intertrigo
• Diabetes: High blood sugar levels can impair the body’s immune response, making it easier for infections to take hold
• Smoking: Smoking can decrease blood flow and the skin's capacity to recover from injuries and fight infections
• Alcohol: Alcohol can weaken the immune system and disrupt the skin's natural barrier, increasing the risk of infections and inflammatory skin conditions like intertrigo
• Immunocompromised: Individuals with suppressed immune systems, whether due to medical conditions, treatments like chemotherapy, or medications such as corticosteroids, are more prone to develop intertrigo⁴
• Poor hygiene: Can breed disease and cause disruption of the protective layer of the skin⁴
• Wearing tight, restrictive clothing: This type of clothing can trap moisture and increase friction between skin surfaces, creating an environment conducive to irritation and infection⁴
• Closed-toe or tight-fitting shoes: Toe web intertrigo commonly affects individuals participating in athletic, occupational, or recreational activities and shoes worn during these activities can trap moisture and create friction between the toes, leading to irritation and infection

By being aware of these risk factors, individuals can take proactive steps to reduce their likelihood of developing intertrigo. 

Symptoms of intertrigo

Intertrigo can present in acute, relapsing, or chronic forms. It may appear suddenly or persist for more than six weeks. The appearance and progression of intertrigo depend largely on its underlying causes.³ The main clinical presentations include:

Rash

A reddish brown, bumpy rash appears due to inflamed skin on both sides of the skin folds. 

Maceration of skin in the affected areas

 In this stage, skin in the affected areas appears soft and soggy, usually leading to further problems of fissuring, peeling and crusting. 

Pain

It differs in severity, however, individuals with intertrigo often feel stinging, burning pain. They may feel uncomfortable, potentially affecting daily activities.

Itching

Itching can occur in the affected area, especially if it is complicated by fungal infection. 

Secondary Infections

The damaged skin becomes more susceptible to the infection, as follows:⁶

• A bacterial infection, like infection due to Pseudomonas bacteria, can produce a foul smell. This may add more to the irritation and inflammation. It, can also cause the formation of plaques and abscesses
• Fungal superinfection will cause satellite papules and pustules. Candidal intertrigo is often associated with a foul-smelling odour

Common sites of infection

There are sites where intertrigo can arise, such as:⁵

• Armpits
• Neck creases
• Eyelid folds
• Behind the crease of the ear
• Between or beneath your breasts
• In your belly folds
• Between your buttocks
• The groin (especially the scrotum)
• Inner thighs
• Between the toe web and finger web spaces

It is highly recommended to talk with your healthcare provider when you experience symptoms, especially if symptoms are recurrent.

Diagnosis of intertrigo 

A doctor will approach the diagnosis through multiple steps, as follows:¹ 

History taking

Your doctor will ask you some questions to figure out the possible causes and risk factors, in addition to helping in distinguishing from other diseases. Questions include: 

• When did it start? 
• How long have you been experiencing these symptoms? 
• Any association? Any chronic diseases?

Physical examination

The doctor will carry out a general examination to evaluate the condition of your skin. 

Inspection of the lesion

It is important to note the characteristics of the rash, the extent and any other associated features.

Culture the lesion

If a bacterial infection is suspected, a bacterial culture may be requested.

Skin scraping

The health professional will perform a skin scraping from the active margin of the lesion.

Adding a 20% potassium hydroxide (KOH) solution to the scraping, then using light microscopy to identify hyphae and/or budding yeast, which indicate a fungal infection.

Detection of specific infections

Your physician can use a wood lamp to detect Pseudomonas or erythrasma (Corynebacterium minutissimum) infections.

Biopsy

When the presentation is unusual or therapy has been unsuccessful, the doctor will suggest a biopsy to rule out malignant conditions.

Laboratory investigations

In case of recurrent cases or cases resistant to treatment, the doctor will request a blood sugar test and other immunological investigations.

Differential diagnosis of intertrigo

There is a range of conditions that need to be taken into consideration. They include the following:⁷

• Seborrheic dermatitis
• Atopic dermatitis (eczema)
• Inverse psoriasis
• Scabies
• Langerhans cell histiocytosis

Treatment options for intertrigo

Treatment approaches depend on whether the intertrigo is infected and whether there are any underlying causes. Treatment options can be classified as follows:⁵

Intertrigo that is not infected

It is essential to keep the area dry, clean, and cool. Here are some tips to help manage intertrigo at home:

Keep the area clean and dry

• After taking a shower
  • Do not rub the affected area. It is better to pat with a fresh towel in order to make sure the region is dry
• Apply a fan or hairdryer
  • Set to "cool" and apply it on the affected area multiple times a day
• Antiperspirant
  • Use a light antiperspirant beneath your arms, under your breasts, or wherever else you sweat a lot

Clothes and textiles

• Wear loose clothes
  • To reduce moisture build-up, use breathable materials like cotton
• Agents for powder drying
  • To keep the afflicted region dry, apply a powder such as talcum powder. Do not mix it with ointments to avoid creating a paste

Extra actions

• Skin barrier creams
  • To decrease friction, apply creams or gels containing petrolatum and/or zinc oxide
• Fibre skin barriers
  • To prevent the skin regions from touching, use cotton or clean gauze
• Topical steroids
  • Over-the-counter, mild steroid creams can be used to reduce inflammation
• Creams with anti-bacterial and anti-fungal properties
  • These can be used to fight the microbial overgrowth that causes inflammation

Infected intertrigo

If a fungal or bacterial infection is associated with the intertrigo the appropriate course of treatment is as follows:

Antifungal therapy

As directed by a healthcare professional, topical antifungal creams can be applied directly to the affected region.

Treatment with antibiotics

Apply topical antibiotic creams, as indicated, to the infected region to treat bacterial infections.

Oral prescription drugs

For more serious infections, your doctor may recommend oral antibiotics or antifungal drugs.

Prevention of intertrigo

There are some preventive measures that are recommended. They include:⁵

• Preserve skin hygiene: Especially in areas where skin rubs together, keep your skin cool, dry, and clean
• Daily routine: Shower every day and make sure you dry off completely
• Options for clothes: Choose materials like cotton that are absorbent and breathable
• Diaper care: Change your child's diaper often to avoid diaper rash
• Weight control: If you are overweight, you may be able to avoid intertrigo by reducing your weight. It is necessary to consult your nutritionist or another healthcare professional for advice
• Control your diabetes: it is essential to follow up with your doctor regarding your blood sugar levels and the appropriate treatment

FAQs

Why does intertrigo smell?

If the intertrigo smells, it may mean it is infected.

Should I go to the doctor for intertrigo?

Yes, as it can be complicated by severe infection.

Should I wash intertrigo with soap?

There is a specific soap available over-the-counter (ketoconazole 1%) shampoo, which can be used as a cleanser. Ask for advice from a pharmacist.

Summary

Intertrigo is a superficial inflammatory skin condition that occurs in skin folds due to moisture, friction, and poor ventilation. It is presented as a red, painful rash. It can become infected. There are risk factors that can enhance the development of intertigo; it is important to talk to your GP about them.