Moist dermatitis

Moist dermatitis may also be referred to as ‘hot spots’ or ‘pyotraumatic dermatitis’. It is a skin condition characterized by localized, moist, superficial reddening of the skin, usually in patches, often as a result of injury or irritation, causing dilatation of the blood capillaries. There are several reasons why guinea pigs may be affected.

Skin affected by moist dermatitis will look red, itchy, weepy and sore. It will feel sticky to the touch and may also feel hot. The skin on the bottom of the feet is most commonly affected. The skin may also be broken and have bled, if the guinea pig has traumatised it by scratching/biting excessively.

Both male and female guinea pigs, old and young can be affected, although the underlying causes of moist dermatitis are likely to affect older guinea pigs.

It is caused by the abnormal and prolonged contact of skin with urine, including urine-soaked bedding.

In cases of dental disease, if the guinea pig is hyper-salivating, the skin around the mouth and under the chin may be affected.

Bladder stones, which make the guinea pig leak urine and be unable to expel urine away from the body, are a potential underlying cause.

Any guinea pig affected by paralysis or paresis will be unable to move away from urine and will sit/lie in it.

Your veterinarian will want to review how your guinea pig is housed as well as performing a clinical examination.

A culture and sensitivity test may be run following swabbing or a tissue biopsy of the affected area of skin.

X-rays, ultrasound and examining the urine (urinalysis) may also be recommended to detect any underlying conditions, such as bladder stones or a urinary tract infection.

In most cases pain relief will be necessary.

The guinea pig will need to be placed onto soft, dry bedding or fleece fabric towelling. The affected area must be kept dry, with wet bedding removed as soon as possible. Any affected fur should be clipped off to allow the skin to breathe and to be cleaned. Topical application of an antimicrobial cream may also be recommended by your veterinarian. Oral antibiotics may be used in severe cases or where there is a secondary infection of the skin (pyoderma).

If your guinea pig suffers from bladder stones, they will need to be surgically removed and dental disease will require the appropriate treatment.

This depends on the underlying cause. If the cause is poor husbandry and this is corrected, then the outlook is good.

Underling medical causes need diagnosing and addressing (such as bladder stones and dental disease) and may need ongoing treatment. In these cases, the long-term prognosis is uncertain.

Yes, to some degree.

Make sure your guinea pigs enclosure is kept clean and dry and they do not have to sit and stand in their own urine and feces.

Clean the toilet areas daily.

Ensure they have comfortable bedding to rest on (hay is ideal) and maintain a suitable diet (high in fiber and vitamin C).

If you notice any sore patches, then consult your veterinarian as soon as possible.