Tricorder Watch

So what could be the Holy Grail of diagnostic equipment? The Tricorder®, that workhorse of the Star Trek TV series would be an obvious choice. With it’s flashing lights and whirring noises, it could measure three different parameters, weather patterns, geology and biology.
In the hands of Dr. Leonard ‘Bones’ McCoy the Tricorder® could diagnose any medical mystery. All it took was a few brief waves of his hand and the Chief Medical Officer of the Starship Enterprise was able to tell a dramatic Kirk and a calm Spock what the creature of the week was.
Point of Care (POC) instruments claim to be Tricorder®, but are they? What makes a good Tricorder®?
First of all it has to be portable. POC instruments are certainly that.
Second of all, they have to non invasive. Unfortunately, POC still need to penetrate skin to get a drop of blood in order to provide a result.
Finally, a Tricorder® will not harm the patient. No one ever gets sick because of McCoy placing it over them.
But despite all the promise that this futuristic diagnostic instrument offers, there are still some modern day realities that would have to be considered if tomorrow one was developed.
You still need to train someone how to interpret the data produced. To be effective, it would have to be in the hands of a healer, not a technologist.
Which brings me to the second point; you would still need a technologist to do the QC and maintenance of the Tricorder®. You couldn’t send one on the away team if it wasn’t working properly.
The Labvocate is constantly on Tricorder® watch, and there are a few developments in progress. This will be discussed in the future.

COPD vs. Global Warming

One more thought about COPD. Previously I wrote that there will be a rise in the number of cases of this condition, as well as becoming the third cause of death worldwide.
Why the increase? Air pollution is targeted as the main cause, especially in developing countries that don't have strict emission standards fro automobiles and industry.
So while there is much debate about whether or not climate change is due to air pollution. Has that caused the wild climate changes lately? At the risk of being called a heretic I'll say the jury is still out on that.
However, the rise of COPD is a definite indicator that air pollution needs to be decreased.
Then maybe we can all start breathing alittle bit easier.

COPD- Future Diagnostic Challenge

If you were to have a group of 100 Canadians in a room, four of them would have heart disease, one of them would be newly diagnosed with cancer, eight would have kidney disease and three of them would have type one diabetes. You would need to have a room holding a thousand Canadians before you would find one with AIDS.
But back to that original room of one hundred, there would a significant amount coughing and hacking from COPD (Chronic Obstructive Pulmonary Disease), twenty five percent to be exact. Currently, COPD is the fourth cause of death in the world, behind heart disease, CVA and lower respiratory infections.
Yet this is a condition that goes largely undiagnosed and treated until it is too late.
Why?
One reason could be that COPD is a broad based term for a number of different diseases. It also doesn't have a set criteria of classification. When does that annoying cough you've had for a month actually become defined as COPD?
But one reason it may go undiagnosed is because the test used to test for COPD is not found in the traditional medical disciplines of Medical Laboratory Science or Diagnostic Imaging. COPD is diagnosed by a test called spirometry.
This procedure measures airflow from lungs and determines if there are any obstructions present which could be causing COPD.
In 2000, it was estimated that 13 million Americans were undiagnosed with COPD. An office version of spirometry would be used the measure the forced expiratory volume at 6 seconds (VEV6) to screen for COPD.
Whatever version of spirometry used, this a test diagnostic facilities should investigate the feasibility of implementing. Accreditation agencies should also be involved to make sure that all spirometry testing is standardized. Finally, clinicians and patients should be educated about this test and the impact COPD will have on Canada's healthcare system.
If anything, it will help those 1 in 4 Canadians breathe a little bit more easier.

Apologies

First of my apologises for neglecting this blog. The last year has been an exciting one, 'thriving on chaos' as Tom Peters would put it. Hopefully I will be able to soon expand on that.
It is gratifying to see that there are people who read this blog and I thank them.
So what will I be trying to achieve with this blog in the following year?
First of all, I'm going to shoot for at least one posting per week.
Second of all, I'm going to still focus on matters concerning laboratory medicine.
But I'm going to add reflections on what I've been doing for the last year. I will be referring to Tom Peters and William Demings more this year. I might even throw in some references to the Book of Job as well, since I think that should be required reading for anyone working in Health Care.
Finally, I will be adding some posts about how lab medicine is affecting my own personal health.
Thank you for taking the time to read my posting. I look forward to your thoughts and comments.
Regards,
Mark Hawkins

Pathology of the Throat and HPV

It has been well documented that the human papillomavirus (HPV) can cause cervical cancer. There is now evidence that HPV main play a role in throat cancer. Does the unsafe sexual behavior presently done mean that there may be an epidemic of oropharyngeal cancer in the future? The or pharynx consists of the middle part of throat behind the mouth including the back one-third of the tongue, the soft palate, the side and back walls of the throat, and the tonsils. Cancer in this area can be difficult to diagnose and treat.
Maybe it’s time to treat this like cervical cancer. Pap smears on women at high risk of developing cervical cancer using Pap smears and HPV testing have helped to drastically reduce the death rate from cervical cancer in the industrialized world. Earlier detection has led to early treatment and better outcomes.
Would performing Pap smears on specimens from the oropharyngeal area be an effective screening test for throat cancer? Or what about gargling with mouth wash, and then centrfiuging the washings down to look for suspicious cells?
Hopefully, someone is reading this blog and it will get them asking the same question. Screening for an illness is the first step to treating an illness.

Explaing the 'e' in eGFR

What’s with this GFR test? For years there we were, medical professionals, just doing our jobs when out of nowhere comes a ‘new’ test we suddenly have to become knowledgeable of. It’s like we’re the only child whose parents have come home with a brand new baby sibling that we’re suddenly suppose to instantly love and accept. We didn’t ask for it, and things were fine until it came along to cause a lot of uncomfortable questions.
Hopefully this entry will answer questions about this newest diagnostic test.
First of all, GFR stands for Glomerular Filtration Rate. The glomerulus is the structure in the kidney responsible for filtering blood, so determine how well it is working can be used to measure kidney function.
Second of all, it’s not a new test. It’s actually a number calculated from a formula using four variables; plasma creatinine, age, gender and race.
Thirdly, the GFR derived from this formula is actually an estimated GFR . That’s why some labs report it as eGFR. Performing an actual GFR requires injecting a patient with a nuclear isotope (125I-iothalamate) and determining how long it takes for the kidneys to filter it out of the body. This is a procedure that cannot be performed on a large scale to screen patients who are at risk of developing chronic Kidney Disease (CKD).
In 1989 the National Institute of Diabetes and Digestion and Kidney Disease in the U.S. performed a study to see what affect diet could have on CKD and two of the tests used were plasma creatinine and 125I-iothalamate GFR.
As a result, a lot of useful data was produced, allowing researchers to develop a formula to quickly estimate GFR. The result was a magic number of 60 ml/minute/1.73 m^2. As long as the eGFR was 61 or greater, than the risk of CKD was decreased. A eGFR of 60 or less indicated further investigation.
Actually then, all the eGFR does is take the plasma creatinine and present is as a number to indicate kidney function.
But here are some ground rules for using the eGFR.
It cannot be used for paediatric patients eighteen years and under cannot have an eGFR performed on them. The test is gender specific. African Americans have a higher content of muscle, requiring a different formula than non African Americans.
Plasma creatinine must be used. Values from Point of care analyzers measuring creatinine using whole blood cannot use this formula.
In fact, any analyzer that measures plasma creatinine to calculate eGFR has to be standardized. What does that mean?
Finally, any analyzer that measures plasma creatinine has to be standardized. What does that mean?
The purpose of the eGFR is to screen patients at risk of developing CKD. However, if the analyzer being used has a high degree of variability , there is the potential for the patient having a wide range of results. One day your patient could have kidney disease with a eGFR of 58, the next day they could be a healthy 62.
An example of a successful standardization program is the one launched by the province of B.C. in 2003. It provided labs with specimens of known creatinine values for them to analyze. These labs then sent the results to the province, which calculated a correction factor for the analyzer.
The results speak for themselves.
Before the standardization program labs on average were reporting eGFR values 16.5% lower than they actually were. This meant that 535,000 British Columbians had been falsely diagnosed being at risk of developing kidney disease. By having labs use the correction factor in their formula for calculating eGFR, 449,000 patients were prevented from being misdiagnosed. Needless anxiety for the patient was avoided as well as the cost savings. The standardization program cost $335,000 to launch, and has a yearly budget of $135,000. Part of that goes towards educating physicians, patients and allied health professionals on the strengths and weaknesses of the eGFR as a diagnostic tool.
So the eGFR has become a useful diagnostic tool. The important thing is to be aware of its limitations, and not to obsess about its numbers.

Genetic Strip Mining

My first lesson on neonatal screening made a dramatic impression on me. I was a student at BCIT in 1985 and it was during a lecture in clinical chemistry the PKU test was explained to me. Before this test had been developed, thousands of newborns each year were destined to be warehoused in state run facilities for the mentally impaired with no hope of any sort of normal life. The lecturer had worked in that time frame to see firsthand these patients.
So what happened to change this?
In 1934 Dr. Asbjorn Folling of Norway observed that certain mentally retarded patients smelt strange. Giving in to his curiosity, he discovered the source of the odour was phenylacetic acid present in the patient’s urine. From his observations, Folling concluded that the mental retardation resulted from genetics and diet. Since the source of the phenylacetic acid was from a chemical called phenylketone, and it was present in the urine, the disease was called phenylketonuria (PKU).
So the next step in treating the disease was to determine how this all caused mental retardation in what appeared to be healthy newborns. The answer was that these infants were lacking an enzyme called phenylalanine hydroxylase which breaks down an essential amino acid called phenylanine . Without this enzyme, there is a build up phenylanine levels in the blood, resulting in elevated levels of phenylanine which are harmful to the central nervous system and if left untreated, lead to brain damage. Unable to properly break down the phenylanine, it is then converted to phenylacetic acid, which is then excreted into the urine.
In 1951 Horst Bickel, a German professor, developed a protein drink without any phenylanine in it, allowing for a infant with PKU to receive proper nutrition. Then in 1958, Robert Guthrie developed a way for testing for PKU that was simple and inexpensive. All it involved was placing a few drops of blood on a piece of filter paper. Eight years later in 1966, hospitals began screening for PKU.
In 1986, that was a very powerful message. Laboratory technologists could improve a patient’s outcome with a very simple test. Families were spared the bitter burden of institutionalizing a child.
Since this first neonatal screening, other tests have been included, such as genetic screening for cystic fibrosis and sickle cell anemia.
Unfortunately now events have occurred that have challenged just not PKU testing be done, but all neonatal screening.
In the four decades since the first PKU screening, genetic testing has grown exponentially. A person’s entire genome can be determined from a single drop of blood. Parents are concerned that blood stored on a PKU card can be used to determine that child’s genetic information, and be kept in a private data base. There is an expectation of privacy that blood samples from the millions of PKU cards collected is not turned into some huge ‘genetic strip mine,’ as researchers and private companies take advantage of this huge pool of DNA.
Parents cannot let fear prevent them from having their infants screened for disease. At the same time researcher’s have to be allowed to do research at a molecular level to help with disease diagnosis and treatment. The millions of PKU cards stored in hospitals world wide make a tempting target.
It is for the good of the newborn that government makes newborn screening mandatory, and it is also good that researchers try to find a treatments and cures for disease. In a historical perspective, did the doctor mentioned earlier, Dr. Folling, have to get permission to begin those groundbreaking experiments that led to the discovery of PKU? What if he had been denied that opportunity to find out why those patients had strange smelling urine, how many millions of patients would have had negative outcomes?
True, there has to be a limit to who has access to stored genetic material, whether it be dried blood on filter paper to tissue biopsies from a cancer patient. It is time for politicians to become not only involved, but informed.
What would my solution be? Earlier I used the term ‘genetic strip mining.’ Treat all stored genetic material as a public resource, and any company that develops that resource pay a royalty to the government for that material. Respect of patient’s privacy is paramount
These are interesting times. But we can’t let fear prevent us from making sure children of every generation have a chance to overcome the challenges they face in this business we call life, including the DNA they are born with.