Dermatitis venenata: symptoms, causes and treatment

Definition

What is dermatitis venenata?

Dermatitis venenata is an irritant reaction to the skin caused by bites or direct contact between the skin and insect saliva or hair. Usually, the type of insect that triggers it is a beetle from the genus Paederus that flies at night or commonly called a tomcat.

This is why dermatitis venenata is also known as dermatitis paederus. This type of dermatitis is more common in hot and tropical climates, which are habitat for the paederus beetle. In Indonesia, the common cause is the tomcat insect.

Contact with the paederus beetle causes a characteristic reddish patch on the skin. The patches can spread around the eye and develop into painful blisters.

The blisters are often linear (elongated), which is why this condition is also known as dermatitis linearis. If not treated properly, blisters can lead to skin infections or leave scars.

Dermatitis venenata is basically a form of irritant contact dermatitis, so the treatment of the two is not much different. If you feel the symptoms, contact your doctor immediately to get the right treatment.

Symptoms

What are the symptoms of dermatitis venenata?

Symptoms usually appear within 8-24 hours of contact. However, other types of beetles may not develop symptoms within 24 - 48 hours. Many sufferers simply do not realize that they have had contact with the paederus beetle.

You may experience symptoms the next day when you wake up. Initially appear reddish patches on the skin. This symptom may be accompanied by itching, burning, or stinging like a prickling.

A few hours later, the red patches usually develop into a blister or a fluid-filled (bouncy) lump. In severe cases, the affected skin may appear darker or experience tissue death.

Insect venom can be spread when you kill insects that stick to your skin or rub itchy skin. If you touch your eyes, the toxins can cause inflammation of the whites of your eyes or the skin around your eyes.

Symptoms of mild dermatitis venenata usually improve after two days. Moderate symptoms with blistering may last 7 - 8 days. Meanwhile, skin that looks darker generally only recovers after one month.

When do you need to see a doctor?

Minor irritation symptoms can improve by cleaning the affected skin with soap and water. On the other hand, the symptoms of severe venenata dermatitis should be treated with medication.

See a doctor immediately if you have fever, joint pain, or muscle aches. Checks are also needed if the insect venom causes inflammation of the inner ear or triggers symptoms of rhinitis (seasonal allergy).

Cause

What causes dermatitis venenata?

In contrast to dermatitis in general, dermatitis venenata is caused by paederin poison. This poison is produced by the pseudomonas bacteria found in insect hemolymph. Hemolymph is a fluid that circulates in an insect's body, much like blood in humans.

Launching DermNet New Zealand, paederin is a chemical substance that has a strong potential to irritate the skin. If the skin affected by paederin is not cleaned quickly, it can cause the release of a protease enzyme that breaks down the protective layer of the skin.

Paederin venom also destroys the chemical bonds between skin cells. Meanwhile, skin cells cannot repair themselves because paederin helps inhibit protein formation, DNA formation, and cell division.

Diagnosis and treatment

How do doctors diagnose this condition?

The diagnosis process begins with a physical examination and skin condition. The doctor will also observe the symptoms that arise, ranging from the form of patches on the skin, skin scrapings, to blisters and crusts that form after the blister dries up.

After that, the doctor will likely perform a biopsy to take a sample of the skin that is problematic. A biopsy is important because dermatitis paederus has symptoms very similar to other conditions, such as:

• heat or chemical burns,
• herpes zoster or herpes simplex infection,
• impetigo,
• dermatitis herpetiformis,
• contact dermatitis, as well
• dermatitis due to other insects.

What are the treatment options available?

Once symptoms appear, the first thing you should do is clean your skin with clean water and soap. This step aims to clear the toxins from the skin and prevent them from spreading to other parts of the body.

After that, compress the skin with a clean cloth soaked in cold water and apply a corticosteroid medication. Several types of corticosteroid eczema ointment can be purchased over the counter without a doctor's prescription, but make sure you follow the directions for use on the drug packaging.

You can also relieve pain and itching with other medications, such as calamine lotion, menthol cream, and topical anesthetics. Some brands of topical anesthetics containing lidocaine and benzocaine are also available over the counter as well as corticosteroid drugs.

Symptoms of severe venenata dermatitis may need to be treated with other medications. Doctors sometimes give iodine tincture (a solution of iodine, alcohol, and a number of other substances) to neutralize toxins and as an antiseptic.

If the blister becomes infected, the doctor will prescribe antibiotics in the form of a drink. The type of antibiotic used generally is ciprofloxacin and other antibiotics in a similar class.

Prevention

How can you prevent dermatitis venenata?

The most effective way to prevent dermatitis venenata is to avoid contact with the trigger, namely the paederus beetle such as the tomcat. In addition, you also need to know how to deal with beetles that stick to the skin.

Below are some simple tips you can do.

• Recognize the characteristics of the paederus beetle.
• Reducing the paederus beetle population in the vicinity of the residence.
• Using a lamp that does not emit ultraviolet light.
• Turn off the lights while sleeping.
• Sleep with a mosquito net while living in an area with a high insect population.
• Get rid of the paederus beetle that sticks to the skin without killing it.
• Do not rub the skin that is exposed to Paederus poison.
• Immediately clean hands affected by Paederus beetles with clean water and soap.

Dermatitis venenata is a type of irritant contact dermatitis caused by contact with Paederus beetles or tomcats. As with other types of dermatitis, medication can help relieve the symptoms caused by this condition.

If you feel the symptoms, immediately visit a dermatologist to get the right treatment. Do not rub the poisoned skin to prevent the symptoms from spreading to other parts of the body.