Health Topic: Urticaria Pigmentosa

Don't know why, but I like health topics :)

I've been meaning to write about this one for a while. It may not really be of interest to any casual readers, but could be useful for anyone who visits when googling this term, etc.!

The words "urticaria pigmentosa" literally mean "pigmented hives". However, this skin condition is not hives, but one of the several forms that mastocytosis can take. Mastocytosis is the name for problems involving abnormal clumping of mast cells in the body -- they are the cells that produce histamine, a chemical that is produced by the body during an allergic reaction. As far as I know, though, mastocytosis does not cause allergies -- however if a child has both allergies and mastocytosis, then they will have extra problems. Also, mastocytosis can react to a wide variety of triggers, and can cause problems not normally associated with allergies.

My younger son (now age 10) - here called "Jiji", has/had a mild case of this problem. It is pretty rare, enough that many doctors have not heard of it (except for dermatologists, of course). It may effect somewhere between 1 to 6 /10,000 people (according to the internet - a few sites estimate 1/10,000, and http://www.mastokids.org/ has a video which estimates there are less than 200,000 people with it in the U.S., which would be less than 6.7 people/10,000).

Urticaria Pigmentosa (I'll abbreviate it as UP) is the form of mastocytosis where the mast cells form little clumps here and there in the skin, and for some reason these clumps draw in melanin, leading to the formation of brown spots which are semi-permanent (they take several years to fade, after the problem has subsided). UP is often found in children, and has a good chance of going away by adolescence.

There may be a few brown spots, or many, and they may be fairly stable, or they may itch and blister easily. So, there is a huge range in the severity of this condition. A child may have hundreds of spots which itch and blister easily, and also the release of histamine from many spots at once can cause other serious problems. Many children with UP carry an epi-pen, like sufferers of serious allergies. Some older children can be teased by other kids because of their spots, and even parents of small children with UP will find that other adults mistake the child's spots for chicken pox or some other unwelcome problem. Hardly anyone has ever heard of UP, so parents usually have to just say something simple like, "He has a skin condition, but it's not contagious".

We were lucky in that Jiji had only about 60 spots at the peak (around age 3 or so), and they hardly ever reacted - mainly just to immersion in hot or cold water, and the friction of drying with a towel. So, when swimming or bathing, or drying off, we would often notice that some spots were red.

I won't go into all the other main characteristics of this problem here, as it would take too long. For that, I suggest going back to Google, and also the excellent website, http://www.mastokids.org/ . Anyway, here is something I wrote up when he was 8 years old. I've edited it slightly to bring it up to date.

Our experience

"Funny spots"

Jiji began to get brown spots on one side of his face, near his ear and jaw, when he was 6 months old. I was very surprised when they suddenly appeared. We had just taken a long car drive on a sunny winter's day, to visit relatives for Christmas, and I thought the sun had somehow caused the spots. I also did some research and found that parsnips can cause sensitivity to the sun. We were living in England, and parsnips had been part of our Christmas dinner. So for the next year and a half, I kept him away from the sun and parsnips (needlessly, as it turns out). Not long after the age of 6 mos., spots appeared in a similar position on the other side of his face, too. I became worried that more and more spots would appear, covering my baby, who had been healthy until then. I caught myself looking at other babies to see if any of them had moles or large freckles, like my baby. It just didn't seem normal. I could never find any other babies with spots like his.

I tried asking the doctor and nurse, but they said, "They're just freckles." Meanwhile, people began asking me if my son had chicken pox, and a friend of a friend who was a doctor asked us at a party, "What are those spots?" We were worried, but didn't know how to take things further, since in England you need a referral from your general practitioner, if you want to see a dermatologist. I didn't want to annoy my GP by asking again and again.

The summer Jiji turned one, I kept him in his stroller under a parasol for most of the summer, while his older brother played in the sun as usual! Poor little thing! But I really felt that his skin was very sensitive to the sun. Meanwhile, the number of spots was increasing little by little. He got a few on his legs, arms, and upper chest. That next winter (when he was 1 and 1/2), he started to get spots on his tummy and back, in places where the sun definitely wasn't going through all his winter clothes. This was a puzzle. Occasionally the spots seemed more reddish, for example after a bath. Sometimes I noticed a new spot that was just red, and later it seemed that a permanent brown spot had formed in that place. I tried looking online for "brown spots", "freckles on baby", and so on, but couldn't find anything at all that seemed to fit. Around that time, we moved to a new town and had a new GP. I was worried, but he still seemed otherwise healthy.

"Diagnosis"

Finally, when he was 2, after a year and a half of worrying and taking various precautions, I had a chance to ask our new GP about the spots. He was immediately interested in them, agreed that they didn't look normal, and referred us to a dermatologist. The dermatologist was quick to diagnose urticaria pigmentosa, and said it was uncommon and he wanted to show a couple of medical students who were there that day. He also brought in another doctor to look, and she agreed with his diagnosis. He had tested it by rubbing a spot, and he said that the spot became red and raised, though I couldn't see much difference. (Side note: on the same visit he also felt that Jiji had eczema, but I realized afterwards that, unclothed, his skin had reacted to my wool sweater, and that he must share my allergy to wool/lanolin.)

I got home and of course searched for UP online, and the diagnosis made sense to me. I was so relieved that it wasn't some kind of cancer or blood disorder, and also relieved that he wouldn't have to stay out of the sun for his whole life! I began letting him go in the sun, and this made the spots less noticeable, as he tanned (also, as he is half Indian and half white, he tans easily). After reading about UP online, I was nervous about adverse reactions to bee stings, etc., and began keeping a bottle of antihistamine syrup at home and at school (just for the first 2-3 years or so, until the problem seemed to be subsiding -- I do still inform his school, "just in case", but have not been taking any other precautions).

The dermatologists wanted to see him every year, just to keep tabs on him. The spots were probably at their peak around age 3 or 4, when he had a total of about 60 spots. A few on each side of his face, a few on each leg and arm, and a few on his back and front. Many of them seemed to be quite symmetrical in arrangement, on the left and right side of his body, and I've read that U.P. can appear to be kind of symmetrical. I have always considered that he has a very mild case of U.P. We have never had any problems with the spots (touch wood), except for occasional redness. The triggers for this were temperature extremes and abrasion (towel rubbing, water jets, etc). By the time he got old enough for other kids to notice the spots, they were already starting to fade away, and the other kids don't seem to have noticed them. Ironically, he ended up getting some cute freckles (real freckles, this time) around his cheeks and nose, and for some reason he is sensitive about them, and says that he doesn't like the way he looks, because of his freckles (?). He has never said anything against the U.P. spots, though, which are less visible from the front, and which are now mostly faded, anyway.

By the age of 8, and I could only find a few of the spots left. They were light enough that a stranger wouldn't really notice them.

"Growing pains"

Jiji has always been very healthy, generally speaking, and is very physically active, likes sports, etc., but he does tend to catch things more easily or worse than the rest of our family. For example, he had flu two years in a row at ages 5 and 6, but no-one else in the family caught it from him. One thing is that he had a very bad problem with "growing pains" in his legs, which started before he could speak, so he couldn't even tell us what the problem was. He used to cry from the pain, at night, and since I and my husband both had growing pains as children, eventually we figured out what the problem was (he would quieten down when his legs were massaged).


As he became older, he was able to tell us that the problem was pain in his legs, and we had to give him children's Tylenol and/or massage his legs in the middle of the night, to help him with the pain (we didn't want to get out of bed and would have him get into our bed and then try massaging his legs, while half asleep - but often it wasn't enough and we had to get up for the Tylenol in the end anyway). Sometimes this would happen up to a couple of times a week. By age 8, he only had this problem once every couple of months or so, but still the pain was bad enough to make him cry in his sleep. When he was younger, he also seems to be prone to pains in his stomach, though these have never been bad enough to cause much inconvenience. From looking at the http://www.mastokids.org/ site, it seems that kids with mastocytosis do frequently have leg and stomach pains. The stomach pains were less severe in our case, but the leg pains were often unbearable for Jiji and would not go away until a parent got out of bed to go get the children's Tylenol. They were frequent enough that we had to make sure to pack the children's Tylenol for any overnight trips, even just one night, in case of a problem.

I am curious to know if there could be any relationship between mastocytosis and garden-variety "growing pains". The reason I wonder about this is that there is a strong history of growing pains in my family. I had them, and my mother and grandmother both had bad growing pains. My husband had them, too, and was the only one in a family of 4 children to have them. Jiji had bad leg pains ("growing pains"), but I learn now that leg pains can be a symptom of mastocytosis (which he does have) ... hmmm... so I wonder if there is any connection.

In the top photo (taken at age 2) you can see about 10 spots on his upper body and arms - the ones on his face were not so visible from the front. The spots were not so big, but it was worrying that I didn't know what they were, and they were gradually increasing in number. Luckily they topped out at around 60 total, on his face, front, back, arms and legs. The two spots visible near his collarbone used to get reddish more often - perhaps they were irritated by the edge or collar of his clothing.

In the bottom photo (also age 2, playing with his big brother), you can clearly see about 5 or 6 of the spots on one side of his face (but only if you click the photo to see a larger version). This photo is a couple of months after the first one, and that is the summer I started letting him go in the sun, so he is much more tan in the second photo (plus it's kind of a dark photo, while the first photo is inside, with a flash).