How to Treat Childhood Cutaneous Mastocytosis

A six-month-old patient presented with pink spots on their skin. Despite evaluations by multiple healthcare providers, the cause of the rash remained unclear. It wasn’t until nine months later that a definitive diagnosis of pigmentary urticaria was made. As the treating physician, I will describe the condition, its underlying causes, and the recommended course of treatment for this patient.

What is urticaria pigmentosa and why does it appear

Urticaria pigmentosa, also known as cutaneous mastocytosis, is a skin condition that presents as dark and itchy patches. The root cause of the dermatitis is the accumulation of mast cells in the skin, which are a part of the body’s local immune system. These cells release substances that cause inflammation in tissues.

Outbreaks of pigment dermatitis can be triggered by various factors including skin damage, exposure to high or low temperatures, taking certain medications, infections, stress, physical exercise, spicy food, and insect bites. While skin spots are the most common symptom of the condition, rarer symptoms can include fainting, nausea, vomiting, bloating, fatigue, and headaches.

Pigmented urticaria is more common in children but can also occur in adults. Approximately half of affected children recover from the condition by adolescence. There is also a systemic form of the disease, in which mast cells accumulate not only in the skin, but also in other organs and tissues such as the digestive tract and bone marrow. This form of the disease is much rarer than cutaneous mastocytosis.

How the child was diagnosed with pigmented urticaria

The child in question was first brought to the attention of medical professionals when they were half a year old. The parent reported that red spots, approximately one centimeter in size, would appear on the child’s stomach and back when they were held. These spots would disappear on their own after some time. During a routine check-up at the clinic, several doctors took note of these spots, with a neurologist speculating that they may be caused by a vaso-vegetative dystonia, a condition that doesn’t actually exist.

The neurologist advised that no treatment was necessary as the child would grow and become more active, causing the spots to disappear on their own. However, by the age of one, the spots were still visible and pale, but did not cause the child any discomfort. A year later, a cardiologist confirmed that the spots had no relation to the cardiovascular system and referred the child to a dermatologist for further evaluation.

How to properly diagnose and treat pigmented urticaria

Pigmented Urticaria Diagnosis. Mastocytosis is an uncommon illness in children, and it can be diagnosed by a dermatologist without any further tests. The doctor simply rubs the affected skin, and if the skin reacts by swelling and forming blisters, the diagnosis is confirmed.

Additional examination is not always necessary. However, if the rash is extensive, a blood biochemistry test, abdominal cavity ultrasound, and a blood test for tryptase, an enzyme found in mast cell granules, may be recommended. An increase in tryptase levels is a sign of mast cell activation. These tests are necessary to rule out systemic forms of the disease.

The treatment of pigmented urticaria typically does not involve medication and the child is simply monitored by a dermatologist. In most cases, the condition tends to resolve on its own during childhood.

However, if symptoms such as nausea, vomiting, and allergic reactions are present, antihistamines, particularly those that stabilize mast cell membranes, may be prescribed. In the case of anaphylactic reactions, hormone medications may be used. The treatment of systemic forms of mastocytosis falls under the purview of an oncologist, rather than a dermatologist.

How Patient Had Two Severe Outbreaks of Pigmented Urticaria

The first outbreak occurred three months after a visit to a dermatologist and two months after the end of treatment. The mother bought cheaper diapers for the son and as a result, his skin was covered in bright red spots. She immediately gave him antihistamine drops and rubbed him with gels, and the redness eventually went away.

The second outbreak was worse and happened about a year and a half later. The son woke up one morning with a red face, and the spots were not only on his body but also on his arms, legs, head, and face. The mother gave him antihistamine drops and started applying what she could find at home, but the next morning new spots appeared. The mother was frightened and took her son to the doctor at a dermatology and cosmetology center. On the fourth day, the new spots stopped appearing and the child was feeling better.

The mother did not take the son for a follow-up visit since everything had returned to normal, and the dermatologist was unable to answer the cause of the exacerbation. It is possible that it was due to the hot weather.

When pigment urticaria flares up, the skin spots may itch and if there are many, symptoms such as nausea, vomiting, and diarrhea may occur. The activation of outbreaks can be caused by various factors.

How to avoid worsening of condition in pigment urticaria

When pigment urticaria flares up, the skin spots may itch and if they are many, sometimes symptoms such as nausea, vomiting, and diarrhea may occur. Activation of outbreaks can be caused by:

• Physical factors, such as physical exercise, skin friction, extreme temperatures, sudden temperature changes, and spicy food.
• Stress.
• Some medications, including nonsteroidal anti-inflammatory drugs, iodinated contrast agents, vancomycin antibiotics, and myorelaxants.
• Infections, including viral infections. It is worth noting that the coronavirus infection in most patients does not intensify the symptoms of mast cell activation.
• Tooth extraction.
• Elevated body temperature.
• Surgical and diagnostic procedures, including biopsy or endoscopy, although many children with mastocytosis tolerate them normally.
• Alcohol in medications. Insect bites.

There is no need to avoid all possible triggering factors, only those that cause exacerbation in a specific case should be excluded.

Remember

• Outbreaks in pigment urticaria occur due to the accumulation of chunky cells in the skin. Skin form of the disease is most commonly seen, but there are also systemic forms, where the bone marrow, nervous and digestive systems are affected.
• Pigment urticaria does not usually require treatment and resolves on its own by adolescence.
• Skin mastocytosis is treated by a dermatologist, while other forms of urticaria are often managed by an allergist.
• Probiotics and sorbents are not necessary for pigment urticaria or allergic reactions.
• To prevent disease exacerbation, it is important to eliminate triggers that cause outbreaks in a specific case.