I’ve heard medical students are told “When you hear hoofbeats, think of horses, not zebras.” Meaning whatever symptoms they see are more likely to be explained by something common than by something exotic.

I’m here to tell you that with my son, a medical appointment often turns into a safari. It’s always zebras.

It started with his teeth, which came in early. We saw the first pearly buds when he was four months old and we had our first visit to a pediatric dentist five months later, since some of his teeth erupted with visible holes in them. I know what you’re thinking. You’re thinking it’s baby bottle mouth (which can also be seen in breastfed babies, so what the heck is with the name?) He was breastfed and no, the holes were not from any substance – formula or mother’s milk – eating away at the teeth. The dentist found no signs of decay. The enamel simply wasn’t there. Ever. His teeth came without all of the advertised features. While the dentist was probing with his little prober tool, a chip of tooth went flying across the room. They were that fragile.

“What would cause it? What would make his teeth be all wrong?” I asked. Among the possible answers, one stood out. If a pregnant mother runs a fever during the stage of fetal development when the tooth buds grow, it can cause dental problems, including incompletely formed enamel. Ah, yes, I spent a large part of the pregnancy ill. Two different intestinal viruses, a series of head colds and a nasty, lingering sinus infection. Zebras prenatally. We opted for baby oral surgery to cap the teeth a few months later.

Fast forward to a couple of weeks before my boy’s tenth birthday. It was a beautiful spring day, perfect for planting flowers, riding bicycles, enjoying the glory of life. I decided to plant flowers and enjoy the glory of life. My husband and son decided to take a bike ride together.

Picture: Mother with her garden trowel, adorning the family yard with festive petunias, waving happily, heart swelling at the joyful sight of her husband and their child bonding in a healthy activity. And know that in a horror movie, this is when the ominous music begins to play, warning viewers that things look a little too perfect now, don’t they? Within ten minutes the father-son duo arrived back home, excursion truncated as the son was experiencing too much pain from his helmet pushing against the bump on his head.

“Bump on your head? Where?” he pointed to a spot just behind the hairline and above his right eye. I felt it with my fingers. Yep, big old goose egg.

“Did you hit your head on something?”

“Not that I can remember?”

“How long has this been here?”

“I don’t know. Two or three weeks.” (As an aside, my son had a very poor grasp on time for a very long time.)

“Why didn’t you say something?”

Shrug.

What’s the opposite of hypochondria? That’s what my second-born has. Tumor on the head? No biggie. Why raise a fuss?

And, oh yeah, it was a bone tumor. We became well-acquainted with the town’s only pediatric neurosurgeon, who eventually took charge of his treatment. After many tests and appointments and scans and x-rays and more scans, it was determined that he had only the one tumor, but it had already eaten away a spot in his skull right down to the meninges of the brain.

One neurosurgery, a bone graft and a biopsy later, we had a diagnosis. The good news: it wasn’t cancer. The weird news: it was caused by an extremely rare auto-immune disorder that can mimic cancer – Langerhans Cell Histiocytosis. This is a disease so rare that the biggest risk factor is being a fictional character on a TV medical drama. In fact, it was the disease of the week once on “House.” LCH affects four or five people out of one million. My son’s doctor might never see another case in her entire career. My son might never have another tumor or symptom from it. Or he might. It’s so weird and rare it’s impossible to say. He’s had no more problems from it so far.

But there was another thing with his teeth after that. What to say about his teeth? I could fill a book with details of his dental woes. When his permanent teeth began showing up, his baby teeth were reluctant to leave. He kept getting more teeth but not losing many, so they came in wicky-wacky. We had some baby teeth removed by his dentist. I honestly think she could have lost every patient but him and still made a pretty good living.

I was overjoyed though, when I saw his top front permanent teeth were strong and complete, even if a little crooked. That lasted a few weeks, until he chipped both when he fell off the jungle gym on the school playground. We would discover many years later that one of the teeth sustained severe permanent damage. This came to light when he got braces at age twelve.

One of the aims of the orthodontia was to bring that front tooth down in line with the others. It had been riding high, never descending completely after getting whacked on the monkey bars. But the tooth didn’t move down. Instead, all of his other teeth started moving up to meet it. Wait, what? I know! That’s exactly what we said, too.

A super-duper futuristic 3-D x-ray revealed the root of the problem. The tooth was ankylosed. This is an uncommon but not unheard of complication that can happen with injured teeth, especially in a human whose bones are still growing. The tooth had fused to the bone up above. It wasn’t going anywhere. Well, not until an oral surgeon cut it out and the orthodontist built a fake tooth-on-a-retainer (like pizza-on-a-stick except a tooth on a retainer) to take its place. The hope is to get an implant if the kid ever stops growing. We’re on hold with that issue for now, but sometimes…

I can’t keep my mind from leaping to TUMOR. For instance when my son and I are sitting in the living room, both reading, as we were a couple of weeks ago, and he says “I hate it when that happens.” And I say “What?” and he says “When I can’t read because the center point of my vision disappears.”

WHAT???!!!!

“Has this happened before?”

“Only a few times.”

“How often?”

“Not very often. It’ll be, like, a few weeks sometimes between one time and the next. And my vision always comes back before too long.”

And he hadn’t thought to mention it. What is the opposite of hypochondria?

The good news this time: still not cancer. Not even a tumor. The weird news this time: it turns out you can have migraines without the headache part. Ocular migraine – that’s what he’s experiencing.

It’s like the Serengeti around here. Always zebras.