【Written by a Vet】Miliary Dermatitis in Cats: Causes, Symptoms, Treatments, and Prevention Tips

Are you familiar with a skin condition called miliary dermatitis? It is a type of dermatitis in cats characterized by small, millet-seed-like red bumps on the skin. In this article, we will explain feline miliary dermatitis in detail.

What Is Miliary Dermatitis? An Inflammatory Skin Disease in Cats

Definition and Characteristics of Miliary Dermatitis

Miliary dermatitis is the most common form of dermatitis seen in cats. Small bumps resembling millet seeds appear on parts of the body or over the entire body. Because the skin surface develops small raised papules and crusts, it feels gritty to the touch.

Often Involving Allergies or Fleas

Feline miliary dermatitis is believed to be caused by allergies. Among these, flea allergy is considered a leading cause. Other potential triggers include mosquitoes, mites, pollen, house dust, mold, food, and atopy.

Main Symptoms and Visual Characteristics of Feline Miliary Dermatitis

Small Red Bumps, Itching, Crusts, and Hair Loss

Red papules can form on parts of the body or all over. Because these papules are itchy, the cat will lick or scratch them. Over time, the papules form crusts, and excessive scratching may lead to hair loss. Sometimes, these crusts may flake off and appear as dandruff.

Commonly Affected Areas

Miliary dermatitis commonly appears on the head, neck, and back, and is most frequently observed on the back.

Differences from Other Skin Diseases

While miliary dermatitis involves the appearance of small papules, secondary bacterial infections can occur when the cat licks or scratches due to the itchiness. In such cases, it may look like bacterial dermatitis. Hair loss may occur, but because the hair falls out in large patches or breaks off due to licking, it looks different from the circular hair loss caused by fungal infections.

Various Causes: Fleas, Allergies, and Stress Are Also Related

Connection to Flea Allergy Dermatitis

Flea allergy is considered a primary cause of miliary dermatitis. There are reports that 35% of cats with flea allergies exhibit symptoms of miliary dermatitis. An allergic reaction to flea saliva can sometimes manifest as systemic miliary dermatitis.

Possibility of Food or Environmental Allergies

Cat food, house dust, and pollen can also cause miliary dermatitis. In the case of food, symptoms may arise after switching to a specific diet. Environmental allergies can sometimes be seasonal.

Mental Stress and Immune Abnormalities Can Also Be Causes

When mental stress leads to a weakened immune system, infections by bacteria or fungi can cause miliary dermatitis. Autoimmune diseases, where the immune system attacks the body itself, can also lead to the development of miliary dermatitis.

Diagnosis and Treatment of Feline Miliary Dermatitis

Diagnostic Methods at Veterinary Clinics

At a veterinary clinic, the process begins with an interview, visual examination, and physical palpation. The interview will confirm whether flea or mite prevention is being practiced, as well as the cat’s dietary habits. During the physical exam, the veterinarian checks the location of the dermatitis and the condition of the papules. They may collect cells from the affected area to examine under a microscope to check for bacteria, fungi, and specific cell types. If an allergy is suspected, allergy testing may be performed.

If the cause cannot be identified through these tests, blood tests or other investigations may be necessary.

Treatment with Steroids, Antihistamines, and Topical Medications

Miliary dermatitis is accompanied by itching, which causes stress. Therefore, managing the itch is essential. Since the itch involves a substance called histamine, antihistamines may be administered for mild symptoms. If symptoms are severe, it is necessary to stop the itching using steroids. If the affected area is small or the itching is well-controlled, topical steroids may be used instead.

The Importance of Flea Control and Allergen Removal

Miliary dermatitis is frequently seen in conjunction with flea allergies. Therefore, if flea control is not currently being practiced, it is essential to begin. Fleas thrive from spring through autumn, which is when preventative medicine is administered, but for cats with flea allergies, year-round administration is recommended.

In cases of food or environmental allergies, it is necessary to remove the allergen. If it is a food allergy, switching to a hypoallergenic diet is required. For environmental allergies such as house dust, measures such as frequent cleaning are necessary.

Tips for Prevention and Preventing Recurrence at Home

Perform Flea Prevention Year-Round

Fleas are active when the average temperature exceeds 14°C. Outdoor fleas can enter the home by clinging to the owner's shoes, clothing, or bags. Once inside, the indoor environment often stays above 14°C, creating a risk for year-round activity. Therefore, practicing year-round prevention, even if there is no known flea allergy, helps in preventing the condition or its recurrence.

Reviewing Diet and Allergen Measures

Miliary dermatitis can also be triggered by food allergies. While food allergies themselves cannot be strictly prevented, it is best to avoid low-quality cat food for both nutritional and health reasons. If an allergy is present, removing the allergen may help reduce symptoms and prevent recurrence.

Creating a Low-Stress Environment and Regular Health Checks

Stress can trigger various diseases, not just miliary dermatitis. To help your cat avoid stress, ensure the room temperature is comfortable and that they always have access to water. Also, provide the number of litter boxes equal to the number of cats plus one. Creating a hiding spot where the cat can retreat is also beneficial.

Additionally, because cat fur is dense, minor cases of miliary dermatitis may go unnoticed. Since the condition is sometimes discovered during brushing due to an increase in dandruff, regular brushing and physical contact are important. If you notice any abnormalities, consult a veterinarian early. Regular health checkups are also vital.

If You Notice Symptoms of Miliary Dermatitis, See a Veterinarian Promptly

Risk of Worsening or Becoming Chronic If Left Untreated

Because miliary dermatitis involves allergies, the dermatitis will persist as long as the allergen is present. Leaving it untreated increases the intensity of the itch, causing the cat to damage the skin further. This can lead to bacterial infection and worsening symptoms, such as pus discharge. While miliary dermatitis is not fatal, it can lead to sepsis if the immune system is compromised.

Is There a Risk of Infection to Other Cats or Humans?

In conclusion, the condition itself is not contagious. However, because flea allergy is a major cause, fleas may be present. Since fleas can jump to and bite other animals or humans, frequent cleaning and regular flea control are necessary.

Summary

Miliary dermatitis is a skin condition caused by an underlying allergy. While small papules, crusts, itching, and hair loss are the main symptoms, managing both the itch and the allergy is essential. Because flea allergy is a major culprit, frequent cleaning and regular flea control are necessary.