Most Common Cause of Intertrigo
The most common cause of intertrigo is moisture, friction, and lack of ventilation between opposing skin surfaces, with Candida species being the most frequent infectious agent when secondary infection occurs. 1, 2
Primary Pathophysiology
Intertrigo is fundamentally a mechanical and environmental problem that creates conditions favorable for secondary infection:
- Skin-on-skin friction in body folds combined with trapped moisture and poor air circulation causes the initial inflammatory dermatitis 2, 3, 4
- The condition occurs in natural body folds (axillary, inframammary, inguinal, umbilical areas) and obesity-created folds 3, 4
- Bodily secretions including perspiration, urine, and feces exacerbate the skin inflammation and breakdown 2
Secondary Infectious Causes
Once the skin barrier is compromised, secondary infections develop:
Fungal (Most Common Secondary Infection)
- Candida species (particularly Candida albicans) are the predominant secondary infectious agents in intertrigo 5, 1, 2
- Candidal intertrigo presents with characteristic satellite lesions on clinical examination 2
- In long-term care facilities, 84% of residents are colonized with yeast, making candidal superinfection highly prevalent 5
Bacterial (Less Common)
- Group A beta-hemolytic streptococcus can cause secondary infection 2
- Corynebacterium minutissimum (erythrasma) may be identified with Wood lamp examination 2
- Bacterial superinfections are less frequent than fungal causes 2, 3
Key Risk Factors
High-risk populations require more aggressive management:
- Obesity is strongly associated with intertrigo and creates additional skin folds 6, 4, 7
- Diabetes mellitus significantly increases risk and complicates management 1, 6, 7
- Immunocompromised status increases both occurrence and recurrence 1, 6
- Care dependency (needing help with hygiene and dressing) is highly associated with intertrigo 7
Clinical Pearls
Important distinctions to avoid common pitfalls:
- The primary cause is mechanical/environmental, not infectious—treatment must address moisture and friction first 1, 2, 3
- When infection is present, it is secondary to the underlying inflammatory process 2, 3
- Prevalence varies by setting: highest in home care (9.6%), followed by aged care facilities (6.7%), and hospitals (2%) 7
- Keeping the affected area dry is the most important intervention, more critical than any topical agent 1