The term intertrigo comes from the Latin inter, between and tergo, I rub. It therefore designates dermatoses located in places where two areas of skin touch and rub together, called folds.

What is it ? 

Intertrigo is a dermatosis localized to skin folds, whether they are affected singly or together, large (inguinal, interlocking, axillary, submammary folds) or small (interdigito-palmar, inter toes, umbilicus, retroauricular, labial commissures , navel).

The different types of intertrigo

There are intertrigos of infectious origin (mycoses, bacteria, etc.), and non-infectious intertrigos which most often result from the localization of dermatoses (eczema, psoriasis, etc.) in the folds.

Clinically, a distinction is made between dry intertrigos and wet and oozing intertrigos.

The causes of intertrigo

Infectious intertrigo

Fungus intertrigo, mycosis of the folds

Yeast infection is the main cause of intertrigo. There are two types of fungi involved:

• Dermatophytes, often giving dry intertrigos
• Candida, which are yeasts, most often causing a shiny, wet intertrigo

Bacteria intertrigos

• Corynebacterium minutissium intertrigo, erythrasma: Erythrasma is the most common bacterial intertrigo in the inguinal and axillary folds.
• Pseudomonas aeruginosa intertrigo: Pseudomonas, also called pyocyanic bacillus, is a bacterium that lives in soil and water. We therefore contaminate ourselves in contact with damp soil (gardening, etc.) or in hot water (spa, etc.) and it often complicates dermatophytic intertrigos through maceration and perspiration. It is therefore common in the inter toe spaces, which suddenly become painful, erosive, oozing or even smelly.

Intertrigos to other pathogenic bacteria

They are caused by staphylococci, streptococci and Gram-negative bacilli (colibacilli). These intertrigos are more common in obese people, diabetics and patients with poor hygiene, and usually complicate an underlying dermatosis.

Non-infectious intertrigos

• Psoriasis: Fold psoriasis or “inverted” psoriasis is common in the intergluteal fold.
• Irritation: It is secondary to the application of local treatments (antiseptic, cosmetics) or by accidental contact with a caustic substance.
• Eczema: It can be a contact eczema by allergy to a deodorant in the armpits for example or an atopic dermatitis preferentially affecting certain folds (retroauricular furrows, folds of the knees, folds of the elbows…).

Rare causes

• Hailey-Hailey disease is a rare inherited skin condition.
• Paget’s disease is a malignant disease corresponding to an intraepidermal adenocarcinoma.
• Crohn’s disease, an inflammatory digestive disease, can affect the intergluteal and inguinal folds
• Vegetative pemphigus is a rare clinical form of vulgar pemphigus affecting the major folds.
• Secondary syphilis can affect the major folds.
• Langerhans histiocytosis is a disease associated with an accumulation in the tissues of Langerhans cells.
• Necrolytic migratory erythema is specific to glucagonomics, malignant tumors of the pancreas.
• Sneddon and Wilkinson’s sub-cornea pustulosis belongs to the group of neutrophilic dermatoses, characterized by the presence of neutrophils in the skin and affecting the large folds.

Diagnosis of the intrigue

The diagnosis of intertrigo is easy: it is defined by a redness of the fold, which can itch, be painful, ooze… It is the diagnosis of the cause which is more delicate. The doctor will focus on characteristics allowing him to orient himself towards one or more causes: bilateral and possibly symmetrical or unilateral intertrigo, presence of desquamation, oozing, evolution by centrifugal extension, clear boundaries or crumbled contours , presence of vesicles, pustules, cracking at the bottom of the fold …

It is often necessary to take a mycological sample (for direct examination and cultivation) or even bacteriological and sometimes a skin biopsy.

Evolution et complications possible

Intertrigo rarely tends to heal on its own. It has a tendency to change and often to worsen due to maceration, friction and sometimes local care which tends to irritate it, can cause allergies or even cause a complication (for example when applying a cortisone cream on an infectious intertrigo).

Bacterial superinfection, pain and cracking are also classic complications.

Symptoms vary depending on the cause of intertrigo:

Infectious intertrigos

Yeast infection

Dermatophyte intertrigo

At the level of the large folds, they give dry and scaly redness with a pink center, most often bilateral and symmetrical, which itch. The evolution is done by a centrifugal extension, with a clear border, polycyclic, vesicular and scaly. The classic involvement is the inguinal fold.

At the level of the small folds, it is the intertrigo inter toe commonly called “athlete’s foot” because it is frequent in the sportsmen, in particular in the last inter-toe space (between the last two toes). It forms a pinkish or red crack bordered by maceration giving the skin a moist, whitish appearance, and may then spread to the back of the foot or the sole of the foot. He often itches.

Intertrigo to candida

At the level of the large folds, they give a glazed and damp red intertrigo, the bottom of which is often cracked, even covered with a creamy white coating. The boundaries of the intertrigo are crumbled with a whitish ruff and a few pustules. Here again, the site of choice is the inguinal fold, but it can also be seen under the breasts.

At the level of the small folds, it is an intertrigo having the same characteristics as in the large folds, but most often sitting between the fingers or on the corner of the lips (perlèche).

bacteria

Intertrigo from Streptomyces powder, l Erythrasma

Erythrasma takes the form of a rounded, well-limited brownish plaque. Wood’s light examination (UV lamp) colors it a “coral” red.

Intertrigo à Pseudomonas aeruginosa

Pseudomonas intertrigo often complicates dermatophytic intertrigos especially between the toes through maceration and perspiration in the shoes, which suddenly become painful, erosive, oozing or even smelly.

Intertrigos to other pathogenic bacteria

They often also complicate the intertrigos of obese people, diabetics and patients with poor body hygiene: the intertrigo turns red, oozing with scabs or pustules.

Non-infectious intertrigos

Psoriasis

Psoriasis of the folds or “inverted” psoriasis gives rise to an intertrigo, preferentially located between the buttocks and on the navel, red, shiny, well defined, and often cracked at the bottom of the fold.

Irritation

The irritation is often related to the application of antiseptics, cosmetics or irritants. Intertrigo is shiny red, wrinkled with sometimes vesicles or even sores and it is common for it to cause a burning sensation

Eczema

Fold eczema can have two origins:

• Allergic contact eczema which is often oozing, itchy and may have blisters. It results from a contact allergy to a product applied in the fold and complicates an intertrigo which becomes oozing or even vesicular and can itch.
• atopic dermatitis, predominantly in the folds of the elbows, knees, neck, behind the ears and often looks drier

Rare causes

Hailey-Hailey disease is a rare hereditary dermatosis, characterized by the recurrent occurrence of vesicles or even bubbles on the neck, axillary hollows and groin grouped in well-defined patches, traversed by very characteristic cracks in parallel rhagades.

Paget’s disease is an intra-epidermal adenocarcinoma (form of cancer), most often vulvar, associated with visceral cancer (urinary or gynecological for example) in approximately 1/3 of cases. It presents as a red patch of the vulva, groin or penis that gradually spreads.

Crohn’s disease, a chronic inflammatory bowel disease, can include skin locations, particularly in the intergluteal and inguinal folds. They appear as cracks, linear and deep ulcers like stabbing, abscesses complicated by fistulas… which can precede digestive manifestations by several months.

Vegetative pemphigus is a rare form of pemphigus affecting the large folds, giving them a vegetative and budding redness.

Secondary syphilis can give multiple, swollen and erosive plaques, sometimes vegetating in the folds.

Langerhans histiocytosis is a disease associated with a build-up in the skin of Langerhans cells. It gives rise to crusty and purpuric skin, predominantly in the retroauricular folds, or even large folds.

Necrolytic migratory erythema is skin involvement caused by glucagonoma, a malignant tumor of the pancreas. It produces raised, scaly red patches of centrifugal extension with a crusty or erosive border that leaves a pigmented scar.

Sneddon-Wilkinson sub-cornea pustulosis is a neutrophilic dermatosis, characterized by the presence of white blood cells called neutrophils in the skin. It produces superficial, flaccid pustules or bubbles which may have a characteristic fluid level called a hypopion pustule. The pustules and bubbles are grouped by drawing arcs or rings or circled mainly on the trunk, at the roots of the limbs and in the large folds.

Risk factors

The folds carry a risk of maceration, friction and heat which promote irritation and microbial proliferation whether it is fungal or bacterial.

The acidity of the folds, obesity, immune deficiencies, pregnancy, diabetes and certain drugs (general corticosteroid therapy, antibiotics) specifically promote candidiasis of the folds.

Our doctor’s opinion

Intertrigos are a frequent reason for consultation in dermatology. They are well classified by causes in this article but in reality they are often multifactorial in practice when seen in the doctor’s office: a dermatophytic intertrigo becomes superinfect with bacteria and presents an irritation and / or an allergic eczema to the products applied by the patient. . In addition, the patient has often already consulted his general practitioner who has tried one or more local treatments further modifying the appearance of intertrigo: their causal diagnosis can therefore sometimes be very difficult, as well as their treatment.

One rule is however often true in intertrigos: it is generally better to dry a fold than to apply greasy substances or creams in thick layers.

Prevention of intertrigo

Simple fold care measures often reduce the risk of intertrigo:

• wash daily and dry the folds thoroughly
• avoid too tight underwear, wool and synthetic fibers / favor cotton socks and underwear
• fight against contributing factors: diabetes, obesity, cortisone cream, etc.

Treatments

Treatment depends on the cause:

Infectious intertrigo

Dermatophyte intertrigos

The treatment of dermatophytic intertrigos is carried out by the application, most often twice daily, of antifungals, in cream, in milk, in spray, in powder:

• ?Imidazolés : éconazole (Pevaryl®), miconazole (Daktarin®), oxiconazole (Fonx®)
• Allylamines : terbinafine (Lamisil®)
• Pyridone derivatives: ciclopiroxolamine (Mycoster®)

In case of resistance to local treatment, the doctor may prescribe an oral antifungal such as griseofulvin (Grisefuline®) or terbinafine (Lamisil®) for 3 to 4 weeks.

Candida intrigues

The treatment first of all fights against the factors favoring candidiasis: avoiding humidity, maceration, chemical or mechanical trauma. An underlying diabetes or even associated digestive or genital candidiasis must also be treated.

It is based on local antifungals, cream, milk, spray, powder, applied twice a day:

• ?Imidazolés : éconazole (Pevaryl®), miconazole (Daktarin®), oxiconazole (Fonx®)
• Allylamines : terbinafine (Lamisil®)
• Pyridone derivatives: ciclopiroxolamine (Mycoster®).

Systemic treatment can be offered for 15 days in the event of recurrence or associated digestive focus (nystatin, Mycostatin®, ketoconazole, Nizoral®).

bacteria

Intertrigo from Streptomyces powder, l Erythrasma

Erythrasma is treated with local antibiotic therapy with erythromycin lotion.

Intertrigo à Pseudomonas aeruginosa

Non-irritating antiseptic solutions are applied to the fold (chlorhexidine: Diaseptyl®, polyvidone iodine: Betadine®…) and / or silver sulfadiazine (Flammazine®). The doctor only rarely uses oral antibiotics, in the event of extension of the infection or resistance to treatment, it is most often ciprofloxacin (Ciflox®).

Intertrigos to other pathogenic bacteria

They most often regress with local antiseptics (chlorhexidine: Diaseptyl®, polyvidone iodine: Betadine®, etc.), combined with local antibiotic therapy with fusidic acid (Fucidine® cream).

Non-infectious intertrigos

Psoriasis

It generally responds well to a combination of corticosteroid and vitamin D gel (Daivobet® …)

Irritation

The treatment of irritation requires local antiseptics (chlorhexidine: Diaseptyl®, polyvidone iodine: Betadine®…), emollients or even topical corticosteroids under medical supervision.

Eczema

Treatment of eczema requires emollients and topical corticosteroids under medical supervision.

Rare causes

• Hailey-Hailey disease requires drying of the folds to limit flare-ups and the risk of bacterial, fungal and viral infections. Surgical excision of the affected folds followed by skin grafting is often the only effective treatment.
• Paget’s disease requires treatment of the associated visceral cancer and excision of the Paget’s disease plaque.
• Vegetative pemphigus requires topical corticosteroids under medical supervision.
• Secondary syphilis is treated with intramuscular injections of penicillin.
• Migratory necrolytic erythema requires removal of the offending glucagonoma.