Archive for the ‘Medical problems’ category

Football helmets protect skulls. They don’t protect brains.

March 16, 2015

The Pediatric Insider

© 2015 Roy Benaroch, MD

A few weeks ago, I wrote about concussions—mild brain injuries caused by trauma. There’s increasing concern that repeated concussions—that is, repeated brain injuries—aren’t good. They can lead to depression, intellectual decline, movement disorders, and other kinds of symptoms that you’d expect from someone whose brain has been injured multiple times.

One tack that athletics departments are taking is to invest in more-expensive helmets. The idea has some appeal—wrap your head in something protective, and then you can bash it into things safely. But there’s a fundamental misunderstanding here. Helmets, the best helmets, can do a really good job at protecting your child’s skull from damage. But no helmet in the world has ever been shown to provide any protection for your child’s brain.

Think about it. The helmet protects the outside of your head, the hair, the skin, the eyes the cheekbones, all of those. People wearing helmets do not get lacerations of the scalp, and they don’t fracture their skulls, because the helmet protects these body parts from damage. But the brain, that is a very different story.

Your brain floats on the inside of your skull, enveloped in fluid. It gets injured not by directly smashing into someone else’s head, or into the ground, or into a windshield. The brain doesn’t strike your steering wheel and it doesn’t get hit by a hockey puck or a boxer’s gloved fist. What strikes your brain, and what causes the damage, is the inside of your own skull.

Picture this: you’re in a speeding car. You, your head, your skull, and your brain are all traveling 60 miles an hour when you swerve off the road into a concrete pole. Very quickly, you and your head stop moving—BAM, you’ve decelerated from 60 mph to zero in just a fraction of a second. If you’re lucky, your head is protected by snapping forward not into the windshield or your steering wheel, but into a relatively-soft air bag. Air bags do a great job to protect skulls and heads. But what happens to your brain? As smart as it might be, brains follow the laws of physics, too. It was just moving at 60 mph, and the thing carrying it, the skull, just stopped. The brain then slams into the front of the skull, from the inside, at 60 mph.

There is no airbag in there to protect the brain. In a car accident, the brain just slams into the inside of the skull. And in a football injury, the same thing happens—the helmet protects the scalp and the head, sure, but the brain still slams into the skull from the inside. Unless they figure out a way to implant a little helmet inside the head, between the brain and the skull, there’s nothing in there protecting the brain.

It’s worse, by the way. The really bad concussions—the most serious brain injuries—come from the brain slamming sideways into the side of the skull, or from rotational forces that shear the cortex, the top thinking part of the brain, away from the base (think of slapping a top from the side and watching it spin. Whee! Brain!) In any scenario, the physics are the same—forces act on the skull to change its motion, and the brain slams into the skull from the inside.

Good sports equipment is still essential for athletes, and I don’t mean to minimize what a good helmet can do. I don’t want poked out eyeballs or broken jaws or caved in skulls, either. But I’d also like to see a more-honest discussion of brain injury in sports, and what we can and cannot do to prevent and mitigate the effects of these injuries. We’re not getting honest info from the helmet manufacturers, that’s for sure.

Help fight childhood cancer, and help me get bald!

March 10, 2015

Heya fellow lovers of science and children! In a few days I’ll be getting my head shaved to help raise money to fight childhood cancer through St. Baldrick’s. It’s a great charity, and it’s a fun way to let the kids know we love them and would do anything to help.

As ya’ll know, I don’t take any advertisers, and I have no financial relationships or anything to disclose about drugs, medical products, or any of that lucrative endorsement stuff that could rake in the dough. I write and manage this blog just to ham it up, have a good time, and hopefully spread some solid info about children’s health. I don’t even accept donations to the blog (there is a “donate” link over there, but it’s just for show. As far as I know no one has ever clicked it.)

If you’ve ever felt that this blog is a useful resource and wanted to thank me by tossing over a few dollars, why not click this link and donate to St. Baldricks? You’ll help children with cancer, and you’ll get a glowy feeling inside. I’ll end up with less hair. It’s a win-win!

Get ready for spring! Allergy therapy update, 2015

March 9, 2015

The Pediatric Insider

© 2015 Roy Benaroch, MD

In last year’s Pulitzer Prize winning* post, I reviewed the medications available for treating the symptoms of spring allergies—antihistamines, nasal sprays, prescription and non-prescription goodness. There’s some new information and changes this year, so it’s time for an update!

First, a study just published provides more reassurance about the use of topical nasal spray steroids and growth. About 220 kids aged 3-9 were randomized to receive placebo nasal spray or intranasal triamcinolone (sold OTC as “Nasacort”), and their growth was followed before, during, and after treatment. Growth when the medication started was very slightly slower (by about an eighth of an inch a year), but that difference was quickly erased by catch-up growth after the medication was stopped. In typical practice, these medicines aren’t used year-round anyway. Bottom line: if there is any effect on growth, it’s insignificant, and it’s temporary.

We’ve also got the first FDA-approved sublingual allergy immunotherapy tablet to come to market. Sold as “Grastek”, taken regularly this can help children and adults overcome allergy to one specific plant, Timothy Grass. Downside: it takes a long time to “kick in”, and it only protects against this one specific pollen—when usually, people with polen allergies are allergic to multiple things. So I’m not sure just how useful this is. Still, it’s an interesting foot-in-the-door for home immunotherapy without the shots. I’m sure we’ll be seeing more of this kind of thing.

Here’s the rundown on all of the other medications, updated for 2015:

Antihistamines are still very effective for sneezing, drippy noses, and itchy noses and eyes. The old standard is Benadryl (diphenhydramine), which works well—but it’s sedating and only lasts six hours. Most people use a more-modern, less-sedating antihistamine like Zyrtec (cetirizine), Claritin (loratidine), or Allergra (fexofenidine.) All of these are OTC and have cheapo generics. They work taken as-needed or daily. There are still a few prescription antihistamines, but they have no advantage over these OTC products. Antihistamines don’t work at all to relieve congested or stuffy noses—for those symptoms, a nasal steroid spray is far superior.

Decongestants work, too, but only for a few days—they will lose their punch quickly if taken regularly. Still, for use here and there on the worst days, they can help. The best of the bunch is old-fashioned pseudoephedrine (often sold as generics or brand-name Sudafed), available OTC but hidden behind the counter. Don’t buy the OTC stuff on the shelf (phenylephrine), which isn’t absorbed well. Ask the pharmacist to give you the good stuff he’s got in back.

Nasal cromolyn sodium (OTC Nasalcrom) works some, though not as strongly as prescription nasal sprays. Still, it’s safe and worth a try if you’d rather avoid a prescription.

Nasal oxymetazolone (brands like Afrin) are best avoided. Sure, they work—they actually work great—but after just a few days your nose will become addicted, and you’ll need more frequent squirts to get through the day. Just say no. The prescription nasal sprays, ironically, are much safer than OTC Afrin.

Nasal Steroid Sprays include OTCs Nasacort and now OTC Flonase. There are also many prescription products, like generic fluticasone, Rhinocort, Nasonex, Nasarel, Veramyst, and others. All of these are essentially the same (though some are scented, some are not; some use larger volumes of spray.) All of them work really well, especially for congestion or stuffiness (which antihistamines do not treat.) They can be used as needed, but work even better if used regularly every single day for allergy season.

Antihistamine nose sprays are topical versions of long-acting antihisamines, best for sniffling and sneezing and itching. They’re all prescription-only (though they’re super-safe). They’re marketed as either the Astelin/Astepro twins (Astepro came out later, when Astelin became available as a generic; it lasts longer) or Patanase.

Bonus! Eye allergy medications include the oral antihistamines, above; and the topical steroids can help with eye symptoms, too. But if you really want to help allergic eyes, go with an eye drop. The best of the OTCs is Zaditor, which works about as well as rx Patanol, which they’re trying to replace with rx Pataday.

 

* That post didn’t win a Pulitzer. Does anyone read these footnotes?

Concussions are brain injuries

February 19, 2015

The Pediatric Insider

© 2015 Roy Benaroch, MD

Many parents (and even some teenagers) realize that kids are going to be using their brains at some point in their lives. I’m getting more and more questions about the effects of concussions—are they going to lead to trouble, down the road? How can they be prevented and treated?

First: let’s abandon the term “concussion.” It’s a weird word that waters down a much simpler term: traumatic brain injury. A concussion is a mild brain injury caused by trauma. So let’s just call it that, “mild traumatic brain injury.” Wordy, but those words say a lot more to parents and children than “concussion.”

How do you know a brain has been injured? Simply enough, it stops working right. A person who’s had a blow to the head followed by a period of brain-not-working has had a brain injury, a “concussion”. The symptoms could include, after the injury, a period of confusion or dizziness or a feeling that you’re “not all there.” Sometimes, but not usually, there’s a brief loss of consciousness. That worth saying again: people who’ve had a mild traumatic brain injury usually do not get knocked out. They just feel knocked around. Later, there are continued symptoms like headache, dizziness, a “fuzzy brain” feeling; sometimes there are also problems with moodiness or irritability, or trouble with sleep cycles. Again, remember, these are all symptoms of an injured brain.

People understand the concept of injuries. You injure your ankle, you expect to need to rest it. Everyone knows rest is the best way to prevent an injury from getting worse, and rest is the best way to prevent an even-worse re-injury. We instinctively know that during rehabilitation for an injured ankle, you’ll kind of walk and run funny—which puts you at risk for other injuries, too.

All of these concepts are exactly the same for concussion, and that’s easy to explain if you remember to think of a concussion as a “traumatic brain injury”. Rest is the key, to allow the brain to heal, to prevent worsening damage from continued trauma, to prevent re-injury of the brain, and to prevent injury of other body parts because you’re not performing well with an injured brain. See? Easy as an ankle to explain.

Of course, resting a brain isn’t exactly as simple as resting an ankle. We can’t use a sling or an ACE wrap (well, you can, but you’ll look weird and it won’t help.) Resting a brain means, well, brain rest: no intellectual work, no school, no physical exercise. Just like you’d rest an ankle until it felt better, resting a brain after it’s injured should continue until there are no symptoms of injury. No headaches, no sleep problems, no fuzzy brain, no dizziness, no trouble focusing. When all of these symptoms have abated, people with mild traumatic brain injuries should gradually advance to more-intense schooling and activities, step by step, until the patient is back up to full activity. If there’s a step backwards—if brain symptoms begin—do exactly what you’d do if your ankle starts to hurt again. Back off the activity and allow more time to heal.

There’s good evidence that allowing a period of time to rest and heal after a mild traumatic brain injury can help prevent re-injury and longstanding symptoms—but we don’t know exactly how long the rest should be. One recent study showed that to a point, too much rest for too long can actually worsen and extend symptoms. Once symptoms improve, it’s a good idea to start back on activities (start slow and advance step by step) rather than continue through a fixed number of days of rest. We have some work to do to fine tune and individualize the best concussion care advice.

While a single concussion, especially with appropriate treatment, is unlikely to lead to long term problems, there are some sobering concerns about people who’ve had multiple concussions. There’s an increased risk of long term cognitive decline, movement disorders, and depression. And we know many athletes under-report concussions. In one study, 30% of high school football players reported a history of concussion, but only half of those had reported the injury. There may be far more concussions injuring far more high school brains than we appreciate.

As I said, many of those brains are going to be used later. Maybe we ought to try to do a better job keeping them in good shape.

Vaccines: Children have rights, too

February 9, 2015

The Pediatric Insider

© 2015 Roy Benaroch, MD

Some people who argue against vaccinations claim that vaccine policies infringe on their “rights”—their rights, as parents, to make medical decisions for their children. It’s a scary, misleading, and chilling message. We need to be careful about where one person’s rights end and the next person’s rights begin. We need to remember that children (their children, and your children too) have rights of their own.

For example, Dr. Bob Sears says in all caps “FORCED VACCINATIONS FOR CALIFORNIANS ARE ON THEIR WAY.” No, Bob. California lawmakers have introduced a bill to eliminate “personal belief exemptions” for public school attendance. No one is going to force any vaccines on anyone, and there are no jackbooted thugs on the way. But if you want to send your child to public school, they’ve got to be vaccinated. There’s still a religious exemption (which is odd—no major religions are against vaccinating) and of course a medical exemption. But “personal belief exemptions” shouldn’t hold water, because personal beliefs don’t prevent disease. Vaccines do. You want your kids in public school, with my kids? Then my kids’ right to have a safe school overrides your rights to not vaccinate your child. Simple.

How far do rights go? Until they start to infringe on the rights of others.

Dr. Bob goes on to say that mandatory school vaccines violate “a parent’s right to make all health care decisions for their child.” He seems to agree with statements from a few politicians in the news lately. Rand Paul, an ophthalmologist and Kentucky Senator, says “The state doesn’t own your children. Parents own the children, and it’s an issue of freedom.”

No, Dr. Paul. Children are not things to be owned. They are not property. They are people, and they have rights too. Do what you want with your own children—anything short of abuse or egregious neglect, and the government won’t interfere. But as soon as your “rights” start to threaten the health of other children, and of our entire communities, that’s where your rights end. And the rights of the rest of us begin.

Can getting cold give you a cold? A win for Grandma!

January 29, 2015

The Pediatric Insider

© 2015 Roy Benaroch, MD

Grandma says, “Bundle up or you’ll catch cold!”

Research just published in the Proceedings of the National Academy of Sciences explains why Grandma may have been right.

A team from Yale University looked at rhinovirus–the most common of the common cold viruses—and the immune response in mice. They found some solid science:

Mouse airway cells infected with mouse-adapted rhinovirus 1B exhibited a striking enrichment in expression of antiviral defense response genes at 37 °C relative to 33 °C, which correlated with significantly higher expression levels of type I and type III IFN genes and IFN-stimulated genes (ISGs) at 37 °C.

In other words, when the nose is at the ordinary body temperature (37 C = 98.6 F), there is a more-robust immune response than when the nose is cold (33 C = 91.4 F). Cold temperatures allow the rhinovirus to replicate and spread more easily.

Does this mean you ought to put a muffler on your pet mouse this winter? Maybe so. And maybe your children, too!

Immunity, breastfeeding, and the timing of measles vaccine

January 27, 2015

The Pediatric Insider

© 2015 Roy Benaroch, MD

Leave it to Disney to make a splash—any day now, we’ll hear that Anna and Elsa have caught the measles themselves (imagine a link to the sisters all covered with spots, looking miserable in the hospital, with a worried snowman and moose cowering in the background. “For the first time in forever… measles is back….”)

I’ve already covered the outbreak in detail. Briefly: over the December holiday someone at one of Disneyland’s theme parks in California brought in measles. At least 5 employees and probably about 40 park visitors caught it, almost all of whom were unvaccinated. Since then, despite a massive public health effort to identify and isolate potentially infectious contacts, the outbreak has spread to about 100 cases in 6 states. Again, and this can’t be repeated too much, almost all of the cases are occurring in people who have not been fully vaccinated, either because they’re babies who are too young, or for other reasons. It’s not yet clear exactly what that breakdown is. Some of the cases could have and should have been vaccinated; it’s likely that others had health issues that prevented timely vaccination. In any case, since measles is super-contagious, it will likely continue to spread, especially among communities with poor immunization coverage. Sadly, this has been an entirely predictable and avoidable outbreak.

A few comments and notes sent in—thanks especially Emily and Jennifer–have asked for more details about the MMR vaccine and how immunity affects how it works. I feel another Q&A coming on….

 

Aren’t newborns pretty well protected against measles, from mom’s antibodies?

The placenta sends lots of important things to baby—oxygen, nutrition, growth factors, love, and what’s called “passive immunity” via maternal antibodies. These are large molecules, a kind of immunoglobulin called “IgG” which mom had made previously after exposures to diseases or vaccines. Good maternal immunity to things like influenza and measles does provide good protection for their newborns. That’s why it’s important for pregnant women to get flu vaccines, and for all girls to get all of their vaccines—so later, when they’re pregnant, their little babies get protection, too.

But those IgGs from momma, they don’t last so long. The “titers” drop off fairly rapidly, and the protection falls quickly. Best protection probably lasts weeks, with some protection falling off over months. By six months of age, there’s probably no protection from maternal IgGs.

However, there’s still some small amount of IgGs circulating. Though they’re not protective, they can interfere with some kinds of vaccines (especially live, attenuated vaccines like MMR and chicken pox.) That’s why these vaccines are ordinarily given at 12 months of life or later. It’s not dangerous to give them early—it’s just that they probably won’t work as well to provide strong, lasting protection. Maternal IgGs do not interfere with the effectiveness of many other vaccines, like the Hepatitis B, DTaP, polio, and the other vaccines given in the first year of life.

 

Can you give MMR vaccine earlier, say if exposure risk is high?

Yes, though it may not work as well or provide protection that’s long-lasting. Current recommendations are to give the first dose of MMR routinely at 12-15 months of life. It should be given early (as early as 6 months) if the risk of exposure is high. For example, the CDC currently recommends early MMR for international travel to Europe, Asia, the Pacific, and Africa. I think it would also be prudent to vaccinate early for travel to California, especially if your baby will be in crowded places like airports or theme parks (California officials have said that these places are safe—IF you’re vaccinated.)

A dose of MMR vaccine given in the 6 – 11 month window will provide some protection, but since the lingering maternal IgGs will prevent it from being fully effective the dose doesn’t “count.” Two further doses will still be needed, following the typical schedule at 12-15 months and at 4-5 years of age.

 

Doesn’t breastfeeding give baby antibodies? Wouldn’t that prevent measles? Or can breastfeeding interfere with the MMR vaccine?

Breastmilk does contain antibodies, but they’re a different kind of antibodies. They’re not the IgG antibodies that circulate in the blood, they’re IgA antibodies that concentrate more in body secretions, including nasal mucus and breast milk. These IgA molecules don’t interfere with vaccines. They provide modest protection against mostly gastrointestinal infections (think diarrhea and vomiting illnesses)—which makes sense, because the breastmilk IgA molecules are swallowed. They don’t make their way into the blood, or at least not very much—like other proteins, if you swallow them they’re mostly torn apart during digestion. Breastmilk IgA provides just a little protection against infections that are caught via the respiratory tract, including the common cold and measles. For instance, a breastfed baby on average statistically will likely get one half of an ear infection fewer in the first year of life. Not a huge impact, at least not in respect to those kinds of infections.

 

Is there any way to test for those maternal measles IgG antibodies? I mean, if my baby’s antibodies are low enough at 9 months of age, could I get him vaccinated then?

Well, you can test for them, but the exact amount doesn’t perfectly correlate with whether the baby will become immune after the vaccine. You won’t know if the vaccine given at 9 months worked well unless you test your baby afterwards—and even then, there’s a grey zone in the measurements.

 

Maybe we should test for immunity? I mean, should we be testing children after the MMR to make sure it worked?

After one dose of MMR, about 85% of children will get complete, lifelong protection against the three components: measles, mumps, and rubella. The second dose, traditionally given at age 4-5, will pick up almost all of the remaining unprotected 15%, leaving only 1% non-immune. Those odds are really, really good—and if a community has high vaccination rates, that 1% of kids whose MMR didn’t take are still well protected by herd immunity. Of course, if vaccine rates fall, it all falls apart. The 1% who didn’t respond are vulnerable, as are babies too young to vaccinate and people with health conditions that preclude vaccination.

Testing for immunity can done under special circumstances, sometimes to help control an outbreak, or in people at risk for losing immunity after chemotherapy, for instance. But the testing is expensive and kind of a hassle (it’s not always easy to draw blood from children, and they don’t like it very much.) Because the vaccine is so safe, it makes more sense to just give the two doses than to test everyone.


Follow

Get every new post delivered to your Inbox.

Join 1,318 other followers