Wednesday, October 28, 2009

Bacterial contamination from toilet flushing

I recently completed a long car trip, and thus spent more than a moment in public restrooms. Once in the stall, purse and road atlas in hand, I faced each time the dilemma of where to stow my gear whilst completing my business. Some facilities have elegant shelves to hold these items, others a hook on the door, some no place at all but the more or less unsavory floor. Imagine then how floored I was to read this item in the latest issue of Health Magazine(1):

"Don't put your purse on the bathroom floor; E coli in spray droplets following a flush may land on it. Hang it in the stall, and clean it inside and out weekly with a disinfecting spray or wipe."

Flushed with doubt, I wondered if this was all some sensationalist piece of journalistic nonsense designed to sell magazines and Wireless Wipes. But alas, check this out and think it over the next time you set your bag on the only dry spot on the tiled floor of a public can:

Microbiologists in the UK (2) contaminated "the sidewalls and bowl water of a domestic toilet to mimic the effects of soiling after an episode of acute diarrhoea." In other words, they dumped a gelatinous turdoid sort of matter containing fecal pathogens into the toilet bowl. Cultures of the bowl water and porcelain surfaces confirmed that significant colonies of the little darlings were clinging for dear life therein. They then flushed, and subsequent testing of the toilet AND the surrounding air confirmed that the bacteria had diminished in numbers in the actual toilet (thank heavens) but that a significant number of them had been jettisoned into the air on aerosol droplets of toilet water.

Dr. Barker and company concluded: "Many individuals may be unaware of the risk of air-borne dissemination of microbes when flushing the toilet and the consequent surface contamination that may spread infection within the household, via direct surface-to-hand-to mouth contact. Some enteric viruses could persist in the air after toilet flushing and infection may be acquired after inhalation and swallowing."

Think about it. Your toothbrushes sit how far from your toilet? My bathroom cup is inches away from mine. Do you close the cover before flushing? All this dainty hand washing, was it before or after you picked up your purse from the bathroom floor?

1) Health. November, 2009. p. 20.
2) Barker, J, Jones, MV. The potential spread of infection caused by aerosol contamination of surfaces after flushing a domestic toilet. J Appl Microbiol. 2005;99(2):339-47.

Tuesday, October 27, 2009

Diagnoses at Denny's

I've mentioned before that I tend to diagnose the passers-by that I see around town and on the road. I was eating breakfast at the Denny's in Moab, Utah this past week when a middle-aged couple lumbered to their seats.

They were both quite wide in the middle, carrying way too much visceral fat packed around their waistlines. Doubtless two cases of metabolic syndrome, a high risk constellation of central obesity plus two of the following: high blood pressure, low HDL cholesterol, diabetes or elevated fasting blood sugar, and elevated triglycerides. Of course, I have no idea about their lab findings, but he no sooner sat down but he pulled out a ziplock baggy jammed with pill bottles.

He was unnaturally red in the face contrasting with his pale arms and legs sticking out from t-shirt and shorts. Sunburn? Shoot, that's a med. student's diagnosis. Idiopathic erythema? Rosacea? Polycythemia vera? His legs, however, had none of the swelling or skin changes associated with venous insufficiency which is a good sign, but his calves and thighs were scrawny which may be a bad sign per a recent report that a low thigh circumference is associated with a higher risk for heart disease!

As they sat, unaware of my clinical musings, she leaned forward, grinning, and said something to him in a low voice. His face immediately crinkled with amusement and softened with affection.

My final diagnosis? They were in love!

Monday, October 19, 2009

Fun with the flu

My patient no sooner sat down when she grabbed a Kleenex, said "Hold on!" and quickly turned away, coughing wetly into the tissue.

"Oh gad," I thought unhappily, "She's going to show it to me."

At that moment, my patient dabbed delicately at her lips, looked over her shoulder, and said, "Don't worry, I'm not going to show it to you."

We both burst out laughing.

Saturday, October 17, 2009

C. difficile and diarrhea

Clostridium difficile (C. diff) is one of many reasons to stay out of the hospital. This bacteria is not a normal inhabitant of the human gut, but once it gets a toe-hold therein, it invades the colon wall, produces toxins, and causes serious illness with bloody diarrhea. Long classified as a nosocomial infection (acquired as a result of being under hospital care for another medical problem), C. diff is now showing up as a community-acquired infection.

The classic patient profile for C. diff sufferers is someone who is old, rather ill, and receiving heavy duty antibiotics such as clindamycin, cephalosporins (which are routinely given before surgical procedures), and fluoroquinolones such as Cipro and Levaquin. Several times a year, I see a patient who has none of those characteristics but has big-time diarrhea due to C. diff. Here's disconcerting news about possible sources of community acquired C. diff.
  1. Meat in Tucson: Researchers there sampled both raw and "ready-to-eat" meat from supermarkets. 42% of the product tested was positive for toxigenic c. diff.(1)
  2. Ready-to-eat salads in Scotland: 7.5% of these "healthy choices" harbored virulent c. diff.(2)
  3. Meat in Canada: 20% prevalence, and more common in winter.(3)
Denver infectious disease specialist Dr. Mary Bessesen theorizes: "I suspect that animals carry it in their gut and on their skin when they arrive at the packing house." She goes on to note that no one knows for sure whether C. diff in the commercial meat supply causes human disease but "what we have thus far is suggestive only--not proof--but it is concerning."

1) Songer, JG et al. Emerg Infect Dis. 2009 May;15(5):819-21.
2) Bakri, MM et al. Emerg Infect Dis. 2009 May;15(5):817-8.
3) Rodriquez-Palacios A. et al. Emerg Infect Dis. 2009 May;15(5):802-5.
4) Vujia, DJ et al. Emerg Infect Dis.
2009 Jan;15(1):69-71.

Sunday, October 11, 2009

"Using the daylight"

Wise words from a century ago(1):

When illumination was poor, people went to bed shortly after nightfall and arose at daybreak. As illumination has become better, they have gone to bed later and later, especially in the cities; and the hour of rising has grown later until, in the summer at least, many persons sleep as much during daylight as in the dark.

This is of course unfortunate. Sleep is never so restful--at least for most persons--during the hours of light as when it is dark. Everyone knows this from personal experience.
The old saw was that two hours of sleep before midnight were worth twice that amount afterward; and while this might not be literally true, the truth in it is that if sufficient sleep is to be obtained after midnight, then much of it must be secured after darkness has ceased. Everywhere one hears the complaint that people are becoming more nervous and are losing the power to rest thoroughly. Undoubtedly, some of this--probably much more than we suspect--is due to the fact that so much of sleep in city life where the increase in nervousness is particularly noticeable must under present conditions be obtained during hours of daylight.

The article goes on to make a case for the establishment of daylight savings time. So now we have daylight savings time, and people are still going to bed too late but now they're also getting up too early, getting insufficient sleep whether it's dark or light. And ever more, they're also becoming more nervous and are losing the power to rest thoroughly.

You cannot flick off bright lights, computers, or TVs and just pop into bed expecting to fall directly to sleep. A case could be made for turning down the wattage in preparation for bed, perhaps reading with just an Itty Bitty Book Light turned onto the page instead of a table lamp flashing our brains. Less Ambien and more common sense.
1)The Journal A.M.A., July 31, 1909, liii, 383, 387.

Saturday, October 10, 2009

Influenza, antibiotics, and procalcitonin

Sure, I know what procalcitonin is, namely that which is not yet but will be calcitonin or the hormone produced by the thyroid which shuts off bone breakdown. Salmon calcitonin (Miacalcin) nasal spray used to be the only drug available for treatment of osteoporosis before Sally Field and other aging baby boomers elevated this condition to a status worthy of new and better compounds.

So what's this got to do with antibiotics? Nothing that we knew about back when I was in med school, I can assure you of that. An article and editorial in a September issue of JAMA(1), therefore, was quite an eye-opener on just how important it is to continue on with continuing medical education.

First, a word or two about lower respiratory tract infections (LTRI) and antibiotic use, a subject that impacts my patients and my decision-making processes every day, especially as swinish flu slams the Denver area. Why do I closet myself several times an hour with some miserable coughing wretch at great personal risk to my own lower respiratory tract? To distinguish ordinary, show-stopping/week-ruining influenza from its many complications, particularly secondary bacterial bronchitis and pneumonia. Often it's me (don't want to overprescribe antibiotics to avoid complications to the patient and antibiotic resistance to the public) vs. them (No time for this! Need antibiotics! Big test/presentation/trip/wedding coming up! Need antibiotics!).

I check out: how sick are they, how long have they been sick, are they having trouble breathing, is their O2 level low, how do their lungs sound, what color are their secretions. Knowing all the while that they feel miserably sick, any days with flu are too many days, their airways are swollen so of course they feel short of breath, and, of course, their secretions are doubtless gross because flu-sloughed cells in the airway plus gobs of white cells will make that which they hack out green.

Surely there must be a better formula other than my experience + intuition + observations. Enter procalcitonin(PCT), and it's not just for regulating calcium anymore. While the thyroid C-cells make PCT and turn it into calcitonin depending on the biochemical need to drop calcium levels in the blood, all sorts of other tissues release PCT when the body is fighting bacterial attack. Under normal conditions, PCT is barely detectable in the blood but levels can soar 100,000-fold with widespread sepsis as bacteria invade the bloodstream.

So here we have a wonderful demonstration of theragnostics (another concept that's new to me) wherein a diagnostic test--say PCT levels--identifies patients likely to be helped by a certain therapy, and then targeted drug therapy is given--e.g.antibiotics--based on those results. And I, with my expensive cognitive skills, am cut out of the equation thus making therapy not only more scientific and less intuitive, but also more accessible and affordable!

Now of course this is not yet anything you'll find in a Walgreen's TakeCare Clinic (until perhaps a handheld PCT-O-Meter is developed) but the possibilities are exciting. Not only could we know just when to treat acute bronchitis or pneumonia with antibiotics because PCT levels indicate a bacterial source, we could use this test in other puzzling situations such as whether or not artificial joints are infected or a patient with worsening chronic lung disease has an infectious complication.
1) Schuetz, P et al. Effect of Procalcitonin-Based Guidelines vs Standard Guidelines on Antibiotic Use in Lower Respiratory Tract Infections. JAMA Sept. 9, 2009 Vol 302, No. 10 1059-1066.

Sunday, October 04, 2009

Emotion and Memory

My friend got lost years ago while on a cross-country skiing trip. The morning paper and the evening news reported search efforts in daily, discouraging detail. Time passed, and the possibility that my friend and her skiing partners lived on became less and less likely. One day, however, while driving home with the car radio on, a breaking-news bulletin announced that they had been found, alive and well if a bit frost-nipped on fingers and toes. I had to pull over and get a grip on my teary emotions.

I can tell you the exact spot I pulled over, the weather, and where I had been. This all quite remarkable as, on average, I've a big picture sort of mind while the details leak before storage in long-term brain files (no surprise this to my husband). My friend later told me that everyone invariably related the minutiae of the moment in which they'd heard of her rescue--this after I'd supplied her with my experience as if it were the most fascinating tale.

So what's with this emotional boost to memory? If you were alive at the time, you can doubtless remember where you were when Kennedy was shot or the moon landing occurred. Likewise for the World Trade Center tragedy and perhaps Princess Diana's death.

Japanese neuroscientists studied emotion and memory in patients with Alzheimer's Disease (AD) following the devastating Kobe earthquake of 1995.(1) They performed brain MRIs on all the subjects, then checked out who remembered the earthquake and who remembered the MRI. The patients were much more likely to remember the quake, suggesting that intense emotions reinforced the memory.

The researchers went on to correlate the ability to remember the temblor with the residual size of the subjects' hippocampus (the brain's memory center) and amygdala (emotional center). Victims of AD are known to suffer from brain shrinkage. Those who retained the emotional memory of waking up to a significant earthquake were much more likely to have a normal-sized amygdala no matter the size of their hippocampus, and, likewise, those with impaired emotional event memory had more intense amygdalar damage.
1)Kazui, H. Emotion and memory. Four studies of the emotional memory in Alzheimer's disease. Japanese Journal of Neuropsychology. VOL.18;NO.3;PAGE.150-156(2002).