Having too much tension in your sphincter muscle or having anal intercourse may also cause anal fissures. In older adults they may occur due to decreased blood flow to the area. Intertrigo describes a rash in the flexures, such as behind the ears, in the folds of the neck, under the arms, under a protruding abdomen, in the groin, between the buttocks, in the finger webs, or in the toe spaces.In adults they can be caused by passing a large, hard stool, or by having frequent diarrhea. Although intertrigo can affect only one skin fold, intertrigo commonly involves multiple sites. Intertrigo is a sign of inflammation or infection. Intertrigo can affect males or females of any age.

Intertrigo is particularly common in people who are overweight or obese (see metabolic syndrome). In infants, napkin dermatitis is a type of intertrigo that primarily occurs due to skin exposure to sweat, urine, and faeces in the diaper area. Toe-web intertrigo is associated with closed-toe or tight-fitting shoes. What are the clinical features of intertrigo? Lymphoedema is also a cause for toe-web intertrigo. Intertrigo can be acute (recent onset), relapsing ( recurrent), or chronic (present for more than six weeks). The exact appearance and behaviour depend on the underlying cause(s). The skin affected by intertrigo is inflamed, reddened, and uncomfortable. The affected skin can become moist and macerated, leading to fissuring (cracks) and peeling. Intertrigo with secondary bacterial infection (eg, pseudomonas) can cause a foul odour. Diabetes, alcohol, and smoking increase the likelihood of intertrigo, especially the infectious form.Intertrigo occurs more easily in environments that are hot and humid.Friction from the movement of adjacent skin results in chafing.Moisture from insensible water loss and sweating cannot evaporate due to occlusion.Flexural skin has a relatively high surface temperature.Intertrigo is due to genetic and environmental factors. The microbiome ( microorganisms normally resident on the skin) on flexural skin includes Corynebacterium, other bacteria, and yeasts. Microbiome overgrowth in warm moist environments can cause intertrigo. Intertrigo is classified into infectious and inflammatory origins, but they often overlap.

Rash crack of buttocks