Giving Thanks

Nov 26 2014 Published by under Kidney Function

Soon we will all sit down and share a meal with family and friends, ostensibly to give thanks for what we have (or at least a day off). As you enjoy your traditions, I want you to give thanks for something else:

Urination.

The patients I take care of, with various kidney diseases, cannot merely sit down and gorge as they want. After all, it's only one day and one (never-ending) meal. No, they will have to limit some foods, take their medications, and generally live their lives as they do every other day of the year. For some, misbehavior could result in discomfort. For others, a Thanksgiving eat-a-thon could prove deadly.

So when you go around the table and say what you are all thankful for, remember to at least think about functioning kidneys and the ability to pee.

It's great to urinate!

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Pediatric Screening Urinalysis in the US

Sep 16 2014 Published by under [Medicine&Pharma]

A Brief History of Recommendations

Back in the 1980s when I trained, the American Academy of Pediatrics (AAP) recommended a screening urinalysis at four age points during childhood: infancy, early childhood, late childhood, and adolescence. Getting urine out of a child can be incredibly time consuming. Stick-on bags can be used in children not yet toilet trained, although results are often contaminated by skin flora. Bags can also leak, making the process a frustrating waiting game.

In 2000 the AAP published new guidelines with screening UA recommended only at 2 ages: 5 years old, the typical age of school entry, and in sexually active adolescents.

Hmm...UA doesn't seem to be a procedure...

Hmm...UA doesn't seem to be a procedure...

Today's well child preventive care guidelines are known as Bright Futures. The components of care are enlarged in the figure at the right; recommended lab studies are listed under Procedures, and no urinalysis can be found in this table or elsewhere in the document.

At present, it would appear that otherwise healthy, asymptomatic children do not need screening UAs.

What About Sports?

After exploring a number of professional sites, including the AAP, I found no recommendations for UAs prior to athletic participation. Blood pressure screening is included, with the recommendation that children with unexplained or uncontrolled hypertension should not participate in power lifting or body building. A urinalysis should be included in the work-up of hypertension in children, but that goes beyond the scope of the sports physical.

So the Answer is...?

Poll

None of the above wins!

None of the above. Currently, no UA is recommended at any age or before any activity for healthy, asymptomatic children.

So what are primary care providers actually doing? And why is this an issue? More fun to come, WhizBangers!

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When to Pee in the Cup

Sep 11 2014 Published by under Kidney Function

Screening urinalysis (UA), usually performed by dipstick in a physician's office, ultimately results in a lot of referrals for nephrologists. I am reviewing this topic, and I will have a series of posts about UAs over the coming weeks. First, I want to start with a poll about what is really recommended for healthy, asymptomatic children:

What are the current recommendations for screening urinalysis by the American Academy of Pediatrics?Next week I will reveal the answers from the crowd, as well as what the real answer is.

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Is the Answer at the RIVUR? #NephJC

Jul 16 2014 Published by under Evidence Based Medicine, Journal Club

This study will be discussed as part of the online, twitter-based Nephrology Journal Club on July 22,2014. More information about the workings of #NephJC can be found here.

The Problem of Reflux

Vesicoureteroreflux (VUR) occurs in approximately 10% of children overall, but about one-third of those with a febrile or otherwise symptomatic urinary tract infection (UTI). VUR is associated with an increased risk of renal "scars." Since it was first described in the 1960's, treatment of this backflow of urine from the bladder to the ureter has been recommended for all affected children. Surgery can create a competent valve at the vesicoureteral junction during voiding, but an early randomized trial showed that prophylactic antibiotics to prevent infection were just as effective as surgery in the scarring outcome.

Despite the recommendations for treatment for 50 years, permanent kidney failure attributed to VUR has not declined in the end-stage database of any country. Improved prenatal diagnosis of infant renal anomalies have allowed us to diagnose VUR in the first weeks of life, prior to any UTIs. Some children without UTIs still get renal scarring, leading some to suspect that "scars" may actually be areas of hypoplasia or other abnormal development due to an abnormal ureteric bud.

The original study showed equivalent results from surgery and antibiotic prophylaxis, but it included no untreated control group to assess the strategy of intermittent treatment of  UTIs when they occurred. The Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial set out to determine if long-term prophylaxis prevented recurrence of UTIs, occurrence of "scars," or contributed to antimicrobial resistance.

The Study

The study was a randomized, double-blind, placebo-controlled trial of prophylaxis with trimethoprim-sulfamethoxazole (TMPS). Children were screened and enrolled after 1 or 2 febrile or otherwise symptomatic UTIs, including positive culture. Bagged urine samples were not allowed. Children in the study ranged in age from 2 months to 6 years and had grades I to IV VUR (severe grade V patients were excluded). Exclusion criteria included other urinary abnormalties, chronic kidney disease, inability to take TMPS, and other selected medical issues.

Studies included dimercaptosuccinic acid (DMSA) scans at baseline and 1 and 2 years later. These scans (the gold standard for kidney scars) were read and scored centrally by two pediatric nuclear medicine radiologists.

Treatment failure was defined as:

  • 2 febrile UTIs
  • 1 febrile and 3 symptomatic UTIs
  • 4 symptomatic UTIs
  • New or worsening "scars" at 1 year

The Results

Baseline characteristics of the children enrolled can be seen here. No significant differences on any parameter existed between the treatment and control groups. Time to first febrile or symptomatic UTI after trial enrollment is shown below:

Figure2

As shown in the paper’s figure 2 above, the two groups separated significantly within the first 6 months of treatment, with TMPS prophylaxis clearly preventing UTIs. By the end of 2 years, approximately one quarter of the placebo group had experienced an infection, while only half that many in the prophylaxis group had fallen ill.

A number of potential modifying factors were assessed for impact on the results, shown in the figure below:

Figure 3

As shown prophylaxis was more valuable for children who presented with febrile, as opposed to symptomatic but afebrile, UTI. Bowel and bladder dysfunction, determined via a standardized survey, also favored the use of TMPS.

Renal “scars” showed no difference throughout the study. Rectal swabs showed no significant difference in the rate of resistance of E. coli to TMPS between the prophylaxis and control groups.

Remaining Questions

Clearly antibiotic prophylaxis reduces the risk of recurrence of UTIs in children with VUR. However, about 75% of children receiving placebo had not suffered a recurrence after 2 years of study. UTIs cause discomfort, school absence, and lost work for parents; even after this trial we have no evidence of long-term damage prevention through the use of TMPS. Antibiotic resistance does not seem to be a big problem in this patient population.

So the question remains: what should we do about VUR?

In my mind, the question is still open. Many families today have qualms about long-term exposure to these medications. Other families dread missing a UTI and would far prefer to take the antibiotic. The tolerance of the family for illness vs the small risks of prophylaxis often prove to be a big factor driving therapy.

That leaves us each a lot of flexibility in our approach to VUR. My personal preference is to watch most cases without prophylaxis initially. Those who have further UTIs in the first few months after diagnosis are encouraged to start prophylaxis and consider surgical treatment. Those without significant recurrences receive follow-up on a regular basis. All of this requires ongoing discussion with the parents and input regarding their tolerance for urinary symptoms.

The pediatric nephrology community hoped that RIVUR would answer our managment questions about VUR. It would appear that we still have more we need to know.

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What I Am Reading: An Open Letter to Alan Bradley

Jan 22 2014 Published by under What I'm Reading

Dearest Mr. Bradley:

I love Flavia de Luce. I first wrote about this almost 3 years ago when I discovered the 10-year-old chemist and binge-read the first novels. I was 10 or 11 when I got my first chemistry set, and I remember the thrill of heating stuff with my bunsen burner, especially if it gave off a horrific odor. I ran out of sulfur quickly.

Click to Amazon

I have pre-ordered each of these books, letting them download to my iPad to delight me once again. The latest volume, The Dead in Their Vaulted Arches, once again left me wanting more. This despite the fact that the book wrapped up some long-running plot questions.

The action begins on the railroad spur to Buckshaw, the family manor. The body of Flavia's mother arrives by train, with her coffin draped by the Union Jack and Churchill in attendance. Finally, we get confirmation that her mother did not go off mountain climbing and die in some madcap heiress scheme. No, she was working for the British government's war effort in the far east. Of course, being Flavia's mother, her death was no accident either. She leaves the name of her murderer written in invisible ink which, I am delighted to tell you, was probably her own urine. Yup, something to make this nephrologist very happy.

I will not reveal any other important murder information here. Suffice it to say there is more than one body and plenty of suspects.

After the main action resolves, Flavia finds out that she is being sent to Miss Bodycote's Female Academy in Canada, the same school where her mother was "finished." This is not the usual finishing school; the chemistry department may be run by a murderer, and it has acquired the latest spectrophotometer for its students. Those facts make Flavia a willing traveler to the other side of the pond.

Unlike earlier de Luce books, this one does not include the title of the next tome in the ending material. Many loose ends wrapped up with this title; does this mean the end of Flavia's adventures? I sincerely hope not. I want to go to Canada with her! Or at least visit Buckshaw when she goes home on break! More chemistry! More poison! More death!

Please don't take Flavia away yet!

Of course, we do have a Flavia de Luce TV series in the works for 2015. I hope the producers do it justice (they seem to have a good track record at least).

What I really want are more books, to see Flavia grow up and achieve and put away more murderers. Please, Mr. Bradley, make it happen!

Sincerely,

Pascale

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To Boldly "Go" Where No Man Has Gone Before

Jul 12 2013 Published by under [Biology&Environment]

The space race of the 1960s resulted in numerous technological advances. Sending people into such a hostile environment provided myriad physiological challenges.

Famously, urination caught the engineers' attention a little too late.

In Advances in Physiology Education, Hunter Hollins of the National Air and Space Museum reviews Forgotten hardware: how to urinate in a spacesuit. A good chunk of the article deals with the development of the pressurized flight suit, necessary for both high altitude spy planes and the space program. These life-saving devices make urination problematic, even for dudes.

The most obvious solution would seem to be some sort of diaper. However, as anyone who has dealt with a baby knows, moist skin may break down and become uncomfortable. For a few hours this could work, but once flight became measured in days instead of hours, the adult diaper became impractical.

Guess how this works

Guess how this works

The engineers looked to another off-the-shelf solution, the condom or Texas catheter. A condom-like sheath rolls over the penis; the opening at the other end connects to some sort of collection bag or bottle. These devices are used medically and for convenience (AKA Bladder Buddy, which the web site assures us makes a great gift). The man urinates and gravity pulls the urine down into the receptacle, away from the urethra.

Oops. No gravity in space. How do we keep the urine from causing trouble?

Up through the Apollo program, astronauts wore pressurized suits throughout their travels, even while in a pressurized cabin. A space-suit valve solved this problem, allowing astronauts to briefly increase the pressure in their suits and force urine into the external receptacle.

So we have dealt with dudes in space. But what about us women? Is this the real reason they grounded us for so long?

Space shuttle and space station missions run longer than those initial Mercury and Apollo missions. In a self-enclosed orbiting world, how can waste be handled? Enter the space toilet.

Click to Enlarge

When we use an earth toilet, we need a single opening. Whatever we excrete, via the power of gravity, falls into the bowl. In most first-world countries, water in the bowl then exits (also via gravity) while more water flushes the bowl and refills it.

Since space has no gravity, we have to do things a bit differently. The diagram shows thigh bars and foot restraints to keep the astronaut on the toilet, something that rarely presents a problem here on earth (unless the user has been drinking a lot).

The space toilet actually has two openings. One appears to be a traditional toilet opening for poop; the other opening is a funnel shaped for the gender of the user. The funnel goes over the urethral opening. Vacuums pull the waste away from the user, making up for the absence of gravity.

The funnel urination system means that in space, women can pee standing up!

This system also allows urine to be processed to recover water. Waste not, want not, when you are miles above the earth!

The lack of gravity also affects urination in other ways. Total body water redistributes, resulting in diuresis shortly after entering weightlessness. The space toilet gets unpacked first! Bladders also get fuller in space. Without gravity, urine does not "pool" in the lower portions of the bladder where most of the sensory neurons lie. We ordinarily feel an urge to void around 1/3 of bladder capacity. In space, the bladder often must get 2/3 full before those nerves get stimulated.

Urine is a fact of our lives, and it must be dealt with, even while we face the final frontier.

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More Than Food and Football

Nov 21 2012 Published by under Wackaloonacy

Once again, pause and be glad that you can pee. Otherwise, your feast would be more limited.

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"Fluid Is a Drug"

Nov 02 2012 Published by under Pharmaceuticals

Kidney Week 2012 is in full swing. Earlier I tweeted from a session on acute kidney injury (AKI) in the pediatric population; the Storify of my brief notes follows down below. One quote from Stuart Goldstein of Cincinnati's Center for Acute Care Nephrology hit home with my nephro-tweeps, specifically the title of the post.

Like all drugs, fluids require a physician's order; nurses take off the order; the pharmacy fills the order; and the agent is administered to the patient. Why do we have a rather cavalier attitude to giving intravenous fluids?

He made another point I liked. We should treat kidney replacement therapy in the intensive care unit the way we do ventilators. You do not wait until the patient is pulseless to institute respiratory support; why do we wait until the kidney completely fails before supporting the patient's metabolic needs?

Of interest, his analysis shows that more than 15% volume overload {(liters of intake - output)/baseline weight in kg >0.15} produces higher mortality and longer length of stay. This is also the point where excess volume seems to complicate respiratory support.

The session provided a great review of the history of continuous filtration therapy and information on pediatric AKI (#PAKI) outside of the intensive care unit.

[<a href="http://storify.com/PHLane/pediatric-acute-kidney-injury" target="_blank">View the story "Pediatric Acute Kidney Injury" on Storify</a>]

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The Carnal Carnival: PEE!

Apr 15 2011 Published by under [Medicine&Pharma]


Click image for original source

This month, the Carnal Carnival feature pee! May I present a collection of recent blogs about kidneys and the golden fluid they produce.

First up, Uremic Frost presents an obituary for Edith Helm, the first female kidney transplant recipient. A 20-year-old newly-wed when she found out she had months to live, she underwent the transplant and ultimately became the first transplant recipient to give birth. She died at 76 in her home state of Oklahoma.

Next, we had an unusual event this week, documented by the Renal Fellows Network. The event was presentation of a new predictive equation for patients who have lost at least 40% of normal kidney function, and it predicts the two year risk of end-stage kidney failure with at least 90% accuracy. As the equation was presented at the World Congress of Nephrology, it also got published in JAMA and an app including the equation was released for all major mobile platforms. Very Media 2.0.

University of the Kidney presents a cool video on the dream of organ regeneration. Over at Nephron Power an excellent slide show on cystic kidney diseases can be viewed.

Precious Bodily Fluids considers how fast your creatinine level would rise if someone really removed both kidneys and left you in a bathtub of ice.

Finally, I have to give my Scientific American guest blog another shot-out. Who wouldn't want to reminisce about Paradoxical Polyuria? Ah...good times.

So enjoy learning a bit more about the golden fluid, and try not to pee your pants in the liquor store!

- Posted using BlogPress from my iPad

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April Carnal Carnival: The Golden Fluid

Mar 16 2011 Published by under Wackaloonacy

A pissing good time...

WhizBANG! has the immense pleasure of hosting The Carnal Carnival on Friday, April 15. The theme will be urine and urination.

Humans, animals, statues... Anything goes as long as that golden fluid (or lack thereof) is involved.

So start sending links to goldenurine@gmail.com or you may regret it. This carnival will be epic!

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