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Wednesday, August 29, 2012

Post #32 Flu Vaccine Update 2012

How is the flu vaccine formulated?
Flu viruses are always changing. Each year, experts study thousands of flu virus samples from around the world to figure out which viruses are making people sick and how these viruses are changing. With this information, they forecast which three viruses are most likely to make the most people sick during the next flu season. These strains are then used to make the flu vaccine for the next flu season.

On February 23, 2012 the WHO recommended that the Northern Hemisphere’s 2012-2013 seasonal influenza vaccine be made from the following three vaccine viruses:

*an A/California/7/2009 (H1N1)pdm09-like virus
*an A/Victoria/361/2011 (H3N2)-like virus
*a B/Wisconsin/1/2010-like virus (from the B/Yamagata lineage of viruses)

While the H1N1 virus used to make the 2012-2013 flu vaccine is the same virus that was included in the 2011-2012 vaccine, the recommended influenza H3N2 and B vaccine viruses are different from those in the 2011-2012 influenza vaccine for the Northern Hemisphere.



When to get vaccinated?

Yearly flu vaccination should begin in September or as soon as the vaccine is available and continue throughout the influenza season, as late as March or beyond. The timing and duration of influenza seasons vary.

While influenza outbreaks can happen as early as October, most of the time influenza activity peaks in February or later. About 2 weeks after vaccination, antibodies that provide protection against influenza virus infection develop in the body.


How many shots will my child need?
This year's seasonal flu vaccine will again include the Novel 2009 H1N1 vaccine which was used during the global pandemic and which was also included in the 2010-2011 and 2011-2012 seasonal flu vaccines. This means your child will only need to get vaccinated with ONE TYPE of flu immunization this year.

If your child is 9 years or older, regardless of what flu immunizations have been given in the past, they will only need ONE immunization this flu season.

However, if your child is under 9 years of age, they may need TWO immunizations this year. See the chart below to assist you in knowing how many shots your child will need this flu season.

Please note that the decision tree sponsored by the CDC (Centers for Disease Control) and ACIP (Advisory Committee on Immunization Practices) are slightly different this year. Our office has decided to use the ACIP decision tree as it is more conservative.

If your child needs 2 flu vaccines this year, they should be spaced apart by a minimum of 4 weeks (28 days). There is no deadline by which the 2nd flu vaccine needs to be completed, but once the minimum 4 weeks has passed, the sooner the better as your child will have optimal protection only after the 2nd immunization.


0 flu shots since July 2010
1 flu shot since July 2010
2 flu shots since July 2010
Under 9 years of age
2 flu shots needed
2 flu shots needed
1 flu shot needed
9 years of age or older
1 flu shot needed
1 flu shot needed
1 flu shot needed

If your child is under 6 months of age, they are too young to receive the flu vaccine.  It is imperative then for all surrounding family members (and caretakers) to receive the flu vaccine as soon as possible to create herd immunity.  Essentially, if everyone surrounding the infant is protected, it decreases the risk that the baby will be exposed to the live flu virus.


Will a quadrivalent vaccine be available for the 2012-2013 season?
Traditionally, the flu vaccine covers 3 different strands of the flu virus and is labeled a trivalent vaccine.  Starting next year some pharmaceutical companies will produce a flu vaccine that will be expanded to include 4 different strands of the flu virus thus adding 33% more protection.

Flu vaccine for the US market is produced and distributed by the private sector. While some manufacturers are planning to produce a quadrivalent (four component) vaccine in the future, quadrivalent vaccine is not expected to be available for the 2012-2013 season.

Of note, on February 29, 2012, quadrivalent flu vaccine manufactured by MedImmune, LLC was licensed by FDA for use in the United States.


Wednesday, July 11, 2012

Post #31 Superfreakohealthonomics

For the past few years I have been intrigued by the field of behavioral economics and economics in general; the works of Daniel Kahneman, Richard Thaler, Dan Ariely, Steven Levitt (writing with Stephen Dubner), Thomas Sowell, Paul Krugman have influenced my outlook on all aspects of life including healthcare.  With medicine increasingly consuming a larger part of our nation's resources, economic analysis of the efficiency and efficacy of doctors, hospitals, and healthcare policies has and hopefully will continue to produce better theory that will in turn yield tangible results in improving outcome per dollar spent. 

Superfreakonomics written by Levitt and Dubner, mentioned above, contains an interesting data-crunching-analysis section regarding the outcome of emergency room visits covering 620,000 visits over eight years, and more than 300 doctors involved in patient care.  In their chapter they discuss various topics including which common complaints are linked to higher death rates (clot, fever, infection, and shortness of breath) and which are linked to lower death rates (chest pain, dizziness, numbness, and psychiatric).

"So a patient with chest pains is no more likely than the average ER patient to die within a year, whereas shortness of breath more than doubles the death risk.  Similarly, roughly 1 in 10 patients who show up with a clot, a fever, or infection will be dead within a year; but if a patient is dizzy, numb, or has a psychiatric condition, the risk of dying is only one-third as high."

Other findings note that you want a doctor who attended a prestigious medical school and residency program, an extra ten years on the job yields the same result as having served a residency at a top hospital, and women in general do a better job at keeping people alive.

The part I found most fascinating was the analysis on what constitutes a good ER doctor.  Essentially, the authors looked at the survival rates of patients after randomizing situations to get a fair comparison of each doctor's ability.  Additionally, they asked the doctors to rank their colleagues to gauge the strength of each physician's reputation.  Surprisingly, the reputation of a doctor had little correlation with the survival rate of his/her patients with overall parity between all physicians analyzed.

What they did find however, was that the best doctors - based on collegial ranking - achieved the same outcomes as weaker ranked physicians with less healthcare dollars spent.  Which means that the best doctors ordered less tests, less medications, and less intervention and still produced the same results as weaker colleagues.  This makes sense: if you have a better fund of knowledge and your deductive skills are stronger, you do not need as many tests to confirm what you can glean from a good history and physical.

No doubt this translates into the primary care setting as well, as insurance companies with their treasure troves of data could easily confirm.  The best doctors do no need as many x-rays, blood tests, and specialist referrals to treat their patients appropriately - of course, in the right situation all of these need to be ordered, but in judicious fashion.
Additionally, the best doctors will utilize less medications and prescribe the cheapest ones available where efficacy is synonymous; this requires a deeper understanding of the pathophysiology of disease and the pharmcokinetics of drugs available.  And, of course, in many instances the astute physician will prescribe no medications at all where nature will run its course and healing will occur regardless of intervention.

Judicious use of resources will not only ensure the most economically sound outcome for the patient, but it will limit their exposure to radiation, reduce overall pain from needle sticks and procedures, and circumvent untoward side effects of unnecessary medications.  Less money, less pain, less side effects - it is a win, win, win situation.  As economists devote more attention to healthcare, I hope the ensuing data analysis will assist the medical field as a whole in becoming more efficient and efficacious.  

Superfreakohealthonomics coming soon to your local Barnes and Noble and doctor's office.

Friday, May 25, 2012

Post #30 Food Allergies: What and What Not To Do

I recently reread an article that I thought poignantly summarized how food allergies should be approached by a clinician. Although the article was written in 2010, the information is scientifically sound and current. I bolded the recommendations as written by the author and added some commentary where appropriate. Parents can use this information to assess whether their doctor is appropriately advising them on how to approach the work-up of their child's food allergies (or lack thereof).

From Medscape Allergy & Immunology, Food Allergy: What You Need to Know by Stephanie A. Leonard, MD, Posted: 11/15/2010.

1. Delaying of potentially allergenic foods until 1, 2, or 3 years of age has not been shown to prevent food allergies. In 2008, the American Academy of Pediatrics amended their earlier position and no longer recommends avoidance of such foods as a preventive measure.

There was an excellent study done in the Journal of Clinical Immunology in 2008 showing that early consumption of peanuts in infancy is associated with a lower prevalence of peanut allergy. Essentially, the study looked at the prevalence of peanut allergies in Jewish children in the UK (where peanuts are avoided in infancy) vs Jewish children in Israel (where peanuts are fed in infancy). The UK had a 10 fold higher prevalence in peanut allergies.

2. Food allergic patients, especially those with a new diagnosis, should be seen by an allergist for complete work-up, education, and management. Children can outgrow their food allergies, and yearly monitoring is warranted.

A complete work-up should include a thorough history and possibly skin testing and/or blood work. The skin tests and blood work are NOT highly accurate when used as a stand-alone test. They must be analyzed in conjunction with a good history and exam to achieve the most accurate diagnosis. Testing by itself will lead to 50% false positives.

3. Specific food IgE levels can be measured after careful history-taking identifies potential allergens. The focus should be on foods ingested within 2 hours leading up to an acute reaction or foods that appear to consistently exacerbate eczema.

IgE levels are the most common blood tests done to help identify food allergies. Common names for the IgE blood test are the RAST (RadioAllergoSorbent Test) or the ImmunoCAP test.

4. Specific food IgE testing panels are not recommended because of the occurrence of false positives and the potential for foods that an individual has been tolerating to be unnecessarily removed from their diet.

Removing healthy foods that a child has been tolerating well, simply because a test shows a possible allergy can make a family's life unnecessarily difficult and possibly hurt the overall nutritional value of a child's diet. Again, a thorough history and exam with the guidance of an experienced allergist should help prevent unnecessary diet modifications.

5. Removing a previously tolerated food from a patient's diet solely on the basis of an elevated specific IgE can put the patient at risk for developing an actual clinical allergy to that food.

Not only could you make your life more difficult than necessary, you may actually create a true food allergy when there was not one to begin with.

6. An undetectable specific food IgE level is not a guarantee that an individual is not allergic. If the history is suggestive, skin testing should be performed (and possibly an oral food challenge as well) before the food is ingested again.

In addition to false positives, the blood tests may also show FALSE NEGATIVES - meaning even though the blood test was negative, a true food allergy may exist. Again, a thorough history and exam with an allergist is important.

7. Specific food IgE levels help to predict the likelihood of reactivity but not the type or severity of reaction. The significance of the levels varies among foods, so they are not comparable.

The level of IgE is often misinterpreted as the higher it is, the more allergic the individual is to that certain food. Many of the "levels" are extrapolated from other foods and have not actually been individually calibrated; therefore the severity of allergy CANNOT be accurately measured by a blood test.

8. Food allergic individuals should carry 2 self-injectable epinephrine devices and antihistamine at all times in case of emergency. Self-injectable epinephrine devices should be renewed once a year.

The newer epipen injection devices are now coming in two-packs. They should NOT be split up. The two-packs are necessary because in 20% of anaphylactic reactions there will be a SECOND phase to the reaction necessitating a second epipen injection. Children should be monitored for 4-6 hours after the first injection to ensure another dose in not needed. Ideally, you will already have sought medical care in an appropriate setting by the time a second reaction occurs, but it is prudent to be prepared.

9. Epinephrine given for an allergic reaction is most effective when administered intramuscularly into the thigh muscle.  Corticosteroids are not useful in the acute management of an allergic reaction because of slow onset, but they might prevent biphasic or protracted reactions.

Corticosteroids are oral steroids that can be given by injection or orally (as a liquid or pill).

10. Adolescents and patients with a history of asthma are at higher risk for fatal anaphylaxis and require additional education. Delay of epinephrine is also a risk factor for fatal anaphylaxis.

Teenagers are at highest risk because they are most likely not to have their epipen when needed or they fail to understand how dangerous a food allergy truly can be.

11. Food allergies have a profound effect on quality of life, and support groups and Websites of food allergy organizations (such as the Food Allergy and Anaphylaxis Network, or FAAN) can be useful.

Food allergies can be a big deal and when they have been appropriately diagnosed by an experienced allergist, the child must be seen regularly and proper precautions must be taken. However, improper use of blood tests and skin tests can lead to restrictive lifestlyes and possibly create a food allergy when there was not one to begin with. As always, judicious use of tests at the appropriate time will lead to the best results and healthiest child.

Friday, March 2, 2012

Post #29 Mom and Dad are on antibiotics, why not the kid?

Let's start with the kid.

Fact: Bacterial illnesses typically need antibiotics. Viral illnesses do not.

Antivirals help in certain rare cases - but for the purposes of this blog I will assume a typical viral illness encountered in a primary care physician's (PCP) office.

Your average child per the Centers for Disease Control and Prevention (CDC) will encounter 6-12 viral illnesses a year (typically colds and stomach bugs) and most of these will be concentrated during the wintertime when viruses tend to spread more easily due to humidity and temperature factors.

What this means is your child will be sick a lot - especially during the winter; and antibiotics will not help any of these viral illnesses. Of course should your child have a bacterial illness (often preceded by a viral illness) they should be prescribed antibiotics. The typical bacterial illnesses encountered in a PCP's office include: ear infections, pneumonia, sinus infections, and skin infections.

The majority of the sick children that I see on a daily basis have a fever or symptoms from a virus. I educate the parents on what a virus is, why antibiotics will not help, and what to look for in case the viral illness progresses to become a bacterial illness - in which case they will need to return to be placed on antibiotics. Overtime, my parents become adept at distinguishing the child who appears viral and the child who seems to have something a bit more serious. This in turn saves them visits to my office and decreases their overall expenditure of time and money - not too mention a significant reduction in frustration.

But every so often, a parent mentions that their adult PCP prescribed them some antibiotics for their recent illness and they wonder out loud why I am not following suit.

It is a fair question. Most of the time from my cursory visual exam of a parent I think to myself it is unlikely the mom/dad needs to be on antibiotics and thus ensues a dance to explain why I don't recommend antibiotics for colds, but perhaps the adult has something more serious - but in truth I suspect most of the time they have the exact same cold as their kid.

So why the discrepancy?

Let's move on to the adult.

The most common reason that an adult is prescribed antibiotics is for bronchitis or sinusitis.

The following information on bronchitis and sinusitis is straight from Up To Date, a website that most doctors trust and pay a hefty annual sum to access.

Bronchitis

Acute bronchitis is one of the most common conditions encountered in clinical practice. Acute bronchitis is a self-limited inflammation of the bronchi due to upper airway infection. Patients with acute bronchitis present with a cough lasting more than five days (typically one to three weeks), which may be associated with sputum production.

Acute bronchitis is one of the most common conditions associated with antibiotic misuse. This respiratory condition is generally caused by a virus. However, reports indicate that more than 60 to 90 percent of patients with acute bronchitis who seek care are given antibiotics.

Guidelines from the American College of Physicians and the Centers for Disease Control and Prevention (CDC) are intended to dissuade clinicians from prescribing antibiotics for acute bronchitis. Both guidelines state unequivocally that pertussis is the only indication for antibacterial agents in the treatment of acute bronchitis. However, the frequency of prescriptions for antibiotics for acute bronchitis has decreased only modestly, from approximately 75 to 60 percent in the past decade. Additionally, the choice of antibiotics prescribed for the treatment of acute bronchitis has changed substantially during the same time span. Prior to 1990 approximately 20 percent of antibiotics prescribed for the treatment of acute bronchitis were broad spectrum; more recently approximately 60 percent of all prescriptions written for this condition were for broad-spectrum agents.

MICROBIOLOGY — The usual causes of acute bronchitis are viral infections of the upper airways including influenza A and B, parainfluenza, coronavirus (types 1-3), rhinovirus, respiratory syncytial virus, and human metapneumovirus.

Although it has been suggested that the bacterial pathogens that cause pneumonia (eg, Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, or even gram-negative bacilli) can also cause acute bronchitis, there is no convincing evidence to support the concept of "acute bacterial bronchitis" caused by these pathogens in adults. An exception is in patients with airway violations such as tracheostomy or endotracheal intubation, or those with exacerbations of chronic bronchitis.

Sinusitis

Acute rhinosinusitis (ARS) is defined as symptomatic inflammation of the nasal cavity and paranasal sinuses lasting less than four weeks. The term "rhinosinusitis" is preferred to "sinusitis" since inflammation of the sinuses rarely occurs without concurrent inflammation of the nasal mucosa.

Acute rhinosinusitis is further specified as acute bacterial rhinosinusitis (ABRS) or acute viral rhinosinusitis (AVRS).

The most common etiology of ARS is a viral infection associated with the common cold. Viral rhinosinusitis is complicated by acute bacterial infection in only 0.5 to 2.0 percent of episodes. Uncomplicated AVRS typically resolves in 7 to 10 days. ABRS also is most commonly a self-limited disease, with 75 percent of cases resolving without treatment in one month.

Distinguishing AVRS of colds and influenza-like illnesses from bacterial infection is a frequent challenge to the primary care clinician. Antibiotics may be indicated for ABRS, but are ineffective and not recommended for AVRS. Despite the overwhelming prevalence of a viral etiology, however, 92 percent of patients in the United Kingdom and 85 to 98 percent of patients in the United States (US) are prescribed an antibiotic when seen for an upper respiratory or sinus infection.

As you can see, for both bronchitis and sinusitis antibiotics are rarely needed in the adult patient. Bronchitis, unless caused by pertussis (uncommon), does not need antibiotics and less than 2% of sinusitis cases are caused by a bacteria.

However, the statistics repeatedly show a high prescription rate of antibiotics for both conditions.

Why?

1. Adults in general are more willing to try medications because they are less concerned about side effects. With their kids they are more scrupulous with what they feed them.

2. Even if the success rate is low, adults feel more pressure to return to work and are willing to get any advantage they can in feeling better sooner.

3. Past success with antibiotics makes adults assume future illnesses continue to require them.

4. Adult doctors know this is what patients expect and they do not want to lose business.

5. Some adult doctors are not aware of the Up To Date information posted above.

6. Educating a patient about the difference between a virus and a bacteria and the statistics on bronchitis and sinusitis can be time consuming.

7. Some doctors feel safer treating all patients with antibiotics so that they do not risk missing the 2% of sinusitis cases that are actually caused by bacteria.

8. Placebo effect.

Over the years, I have convinced many of my close friends and parents of patients of the above information. This has saved them trips to their doctors, co-pays, trips to the pharmacy, money spent on antibiotics, and unnecessary side effects incurred.

Of course, this is not to say that antibiotics are never needed. But just as my patient's parents have become astute with when their kids have something greater going on than a typical cold, adults too can become more in tune with their own body's illnesses.

Overtime, this will lead to better health and less frustration. Antibiotics are one of the greatest advances of modern medicine, but they are powerful tools that need to be utilized judiciously.

And often if your pediatrician is not recommending an antibiotic for your child, chances are you don't need one either.

Saturday, January 28, 2012

Post #28 Respiratory Syncytial Virus (RSV) - Dispelling Some Myths

One of the common fear-inducing germs that moms ask me about during the wintertime is the Respiratory Syncytial Virus more simply known as RSV. Most moms correctly recognize the germ as a potentially devastating illness, however there are some common misconceptions about the germ that I would like to clarify.

Probably the most common misconception is that RSV is always dangerous; while RSV can be dangerous it typically is not.
RSV is one of many known viruses which causes the common cold (there are over 200). The majority of people who acquire RSV will go on to have typical cold symptoms including cough, runny nose, and possibly fever. Most people will recover within a few weeks without any long term complications.

However, the very first time a human being catches RSV, there is a higher probability of lung involvement leading to either bronchiolitis (inflammation of the small airways) or pneumonia (inflammation of the lungs involving the air sacs); as such the younger you are the more likely you will have lung involvement with an RSV infection. Additionally, there is greater risk of severe disease in children who were born premature (especially less than 35 weeks gestation).

So if your child is younger than 6 months of age and in particular if they were under 35 weeks gestational age when born, there is greater risk of serious illness from an RSV infection.

The older your child becomes three things will favor them against serious complications:

1. There immune systems will mature.
2. They will become physically larger (as will their airways).
3. They will encounter the RSV germ repeatedly giving them greater antibody protection with each subsequent illness.

It should be noted that the elderly are also affected more significantly by RSV than a healthy young adult, however as a pediatrician I do not have any expertise in this population.

The second common misconception is that RSV can be avoided - it cannot. Almost every child will become infected with RSV at least once by their second birthday and reinfection is common.

RSV, like other cold viruses, is spread through respiratory droplets (i.e. sneezes and coughs) but more commonly it is spread via direct contact with other infected children and the surfaces they touch. It really is a matter of WHEN and not IF your child will catch RSV. As stated above, children's bodies handle RSV better as they get older.

Thus if your child is a preemie and/or they are under 6 months of age, it makes sense to take some precautions to delay the initial onset of the inevitable first acquisition of RSV. Typical hygienic habits are what serve you best: washing hands, portable hand cleanser, and covering sneezes appropriately (elbow method is best).

The last misconception is not as common and is not really a true misconception. As a pediatrician, I am often asked whether RSV lung infection will increase the risk of asthma in the future. The short answer is - it's complicated.

A good way to think about this is the chicken or egg analogy.

Do kids that are more prone to asthma genetically have a greater propensity of having lung involvement with their very first RSV infection?

Maybe.

Or does an early infection with RSV increase the chances of having asthma later in life?

Maybe.

One of those statements is likely true and possibly both. The research has not definitively answered either question adequately and we will likely never know for sure. What we do know is that RSV infection in the lungs (everyone eventually gets it but not everyone gets involvement of the lungs) has some correlation with recurrent wheezing. But we also know that long-term there are no permanent changes found in the lungs of these same children - at least not as a result of RSV.

The bottom line is that your child will catch RSV at some point in their life and it will likely manifest itself as nothing worse than the common cold. However if your child is under 6 months of age and particularly if they were born premature, healthy hygiene may prevent lung involvement and thus reduce the risk of serious illness. Finally, should your child have lung involvement with their RSV illness, they have a greater risk for recurrent wheezing, however the RSV germ should not cause long-term changes in their lungs.