Renal symptoms of HFI

[antonia]

Hi, my name is Antonia, and I'm new to this board. I have a five year old daughter who I suspect may have HFI. I have so many questions but in an effort to begin somewhere I will start with this - HFI is known to cause kidney damage but what are the signs or symptoms of that? My daughter has a history of what we originally believed was fructose malabsorption, but recently she landed in the hospital with hypoglycemia along with severe stomach pain, nausea and vomiting. An ultra sound also revealed she had thickening of the bladder wall and one of the ducts in between the kidney and bladder was also enlarged. Her GI doctor told us, yesterday, that this may indicate she could be having kidney reflux. Is this an indicator of HFI? She has always had frequent urination, sometimes after drinking at a meal she'll have to go constantly, every 5 to 10 minutes, making it impossible to avoid accidents with regular potty breaks. Hence, potty training has been a challenge during the day and we have not even attempted it at night. Is incontinence a symptom of HFI?

I have had her on somewhat of a HFI diet the last two weeks and she has drastically improved. But, I really have no idea what I'm doing. I'm worried about her nutritional needs being met. I'm still giving her some vegetables but I should probably stop doing that. She had a reaction after eating a small salad tonight. We don't have a consult with genetics until mid July. In the meantime, her GI agreed to put in an order for a DNA blood test with the BU HFI lab, but it could be months before those results come back. We are also going to set up an appointment with a urologist regarding the ultra sound results. All if this pending, but if anyone has advice for how to manage in the meantime I would be so appreciative.

[colormist]

Hi Antonia!
Welcome to the board. Hopefully we can help you a bit on your journey to diagnosis.

Before I answer your question about kidney concerned, I wanted to address your more-immediate concern about meeting your child's nutritional needs. I'm going to recommend you start a food diary AND start an account at Cronometer.com . The Cronometer website (which is free, by the way) will break down the nutritional information in your daughter's diet and let you know what vitamins are missing. My diet is chronically low in Vitamin C, E, and K and a little low in potassium. I take a multivitamin to help fill in the holes with what's missing in my diet. If you do find that you need to give your daughter a multivitamin, make sure it's free of sweeteners and additives.

So, I can't really tell you much about the kidney connection. HFI isn't really documented that well, so I can only tell you what I experience. If I eat something that has an unsafe sugar in it, I usually get ravenous afterwards and drink a LOT of water. This causes me to go to the bathroom frequently. There's some sort of threshold of sugar that causes kidney pain (low back on one side (or even both--right around the hips) but I'm not sure of what it is. After going to the bathroom, the urine smells sickly sweet. I'm under the impression that (other than vomiting), expelling the unsafe sugars out of the body via the urinary tract is the only way for a person with HFI to process fructose and sucrose. The more unsafe sugars a person with HFI consumes, the more difficult it is to get the poisonous sugars out of the body.

And if she does have HFI, that is an understanding that you, your daughter, and the people that care for her will have to come to. Fructose, sucrose, and other unsafe sugars are a form of poison to people with HFI. It can put them into a coma and possibly kill them in large enough quantities and even the smaller quantities can cause weeks of medical issues and complications.

The good news is that HFI is completely manageable and we're all living happy, healthy lives by sticking to a strict diet. It makes social functions rather difficult, but other than that we manage just fine.

[antonia]

Thank you colormist. I will check out cronometer. I don’t want to over supplement either, I’m afraid that would put more stress on her possibly already overworked kidneys. Cronometer should help me determine what supplements she truly needs. Finding those exact supplements without sugar or sorbitol, however, could prove to be a challenge. We have seen a naturopath in the past, through our GI’s office, for that sort of thing and she works with fructose malabsorption patients so maybe she could help.

Interesting that all the literature states that HFI causes kidney damage but there is no documentation on how it is manifested. Frustrating. Palmera has complained of side pain on occasion, usually right after eating, but it does not last too terribly long. Usually she describes pain all across the abdomen at belly button level. This is where her chronic pain has been. After several weeks on a HFI diet, however, that pain seems to be gone… fingers crossed! I hope that means that if the kidneys and/or liver have been damaged that they have the ability to rehabilitate or heal.

I was also told that she had sugar in her urine the first time she was hospitalized for hypoglycemia, as well as ketones/acid. They told me the acid was normal for someone in the fasting state (although I don’t really consider 8 hours to be a fasting state myself). Her urine tested normal by the time we left the hospital, about 24 hours later.

I continue to consider other disorders with similar symptoms but always come back to HFI. It’s the only thing that explains the hypoglycemia. I don’t understand, however, how she could have gone this long with HFI eating fruits and vegetables, albeit low fructose fruits and vegetables in extremely small quantities ever since she was 3 (when we thought she had fructose malabsorption). Her severe symptoms and hypoglycemia started after we tried to increase quantities of those fruits and vegetables at the suggestion of her dietician. Before that she was kind of riding the line, not doing terrible but not great either. She did exhibit aversion to sweets as an infant and young toddler (no one believed me, so I just didn’t talk about it), but was able to eat some fruits and vegetables without obvious or extreme issue, so I find this very confusing. Are there different degrees of severity of HFI, or do levels of adolase B acitivity vary among HFI patients? I’m guessing this is unknown, but had to ask.

Thanks so much,
Antonia

[colormist]

We're not sure if there are different degrees of severity with HFI. A lot of us have different responses to eating sweets. I would actually love to eat certain berries and more vegetables as I think they taste amazing, but my liver does not agree. Regina drinks a diet soda with aspertame without any issue, whereas I would not even be able to force myself to take one swallow due to the taste.

Before my diagnosis, I ate all kinds of things I shouldn't: berries, tomatoes, salads, sweet wine, beer, bread with sugar in it. I was managing fine, but I'm sure it would have come back to bite me in the ass later. Once I went completely off everything with fructose in it, I had a new understanding for how "normal" felt. I think I spent my first 20 years in a constant state of nausea and pain--it was so regular that I didn't even feel it anymore. Of course, if I ate something really sweet (like pop, cake, or fruit juice) then I'd have to hang around a waste basket. I can't imagine what my liver was like back then! This might be what your daughter was experiencing--just getting used to feeling ill all the time and then being ill is just normal for her. Once you removed the fructose in her diet, she has a "new normal", like, this is what healthy should feel like.

It does sound like maybe your daughter has HFI and I hope you get your answers soon!

I was told my my doctor that livers are just like a starfish and if one part gets damaged, it just grows right back. That was a bit of relief. I've had kidney pain off and on for 15 years now and a recent ultrasound of my kidneys showed they looked normal.

Good luck Antonia! Please keep us posted!

[hfimomof3]

Frequent urination makes me think diabetes but I am assuming you have already tested for that? Young children refusing sweet foods on their own should make a doctor wonder about HFI, but at the same time there are a number of possible conditions that can make kids have nausea, vomiting, etc, after eating, and different disorders will require different types of care, so getting the diagnosis correct is really important. I am glad it sounds like your doctor is being careful.

What kinds of fruits and vegetables did she eat over the long term? I ate carrots and tomatoes for years before realising that they were making me ill. When I cut them out of my diet (including processed forms such as ketchup), I felt a lot better. You might also consider cutting out onions or switching to a less "juicy" type of onion such as scallions, because onions do contain sugar. I agree with Colormist that chronic low level ingestion might result in feeling slightly ill all the time, but not ill enough to recognise that dietary fructose is the cause.

My understanding is that HFI can result in both kidney and liver damage if fructose is ingested, because the toxic intermediate builds up in both places. However, the liver is the place one hears about most. I don't know if that means kidney damage is less common, less severe, or just less studied. Is her liver enlarged? Have her liver enzymes been tested?

What vetegables is she eating now? Can you give us a typical dietary day for her?

One of the main vitamins she will need that will not naturally be in her diet is vitamin C. You should be able to get vitamin C over the counter without sugar. I use Nature Made brand, it is just vitamin C. Some brands use orange flavor which I despise. Ask your doctor about the dose. YOu can crush it and put it in water for her.

[colormist]

Hi Antonia! I just watched a video that talked about different kinds of fructose intolerance. You can view the video here: youtu.be/AsEx6luLDko (around 5:30 is when he starts to talk about fructose conversion in the liver and discusses two types of fructose disorders: Essential Fructosuria & HFI)

I skimmed through your posts above a second time and didn't see any mention of elevated liver levels. Did the doctors test her liver levels?

In the video I linked above, it describes how Essential Fructosuria is a deficiency of Fructokinase in the liver. Fructose doesn't get processed at all and is expelled through the kidneys & bladder.

With HFI, the fructose is half-processed, but is hung up because HFI lacks Aldolase B (which is step 2 in processing fructose). The fructose then just hangs around in the liver causing lots of problems before being expelled by the kidneys & bladder.

I'm not sure if it's either condition, but I thought I'd let you know about Essential Fructosuria (since it primarily impacts the urinary tract).

[antonia]

Thank you both for your feedback.

The video is very informative without being over my head technically, so thank you for that! Interesting about fructosuria. I had run into that in previous searches and it left me scratching my head, now it makes more sense. Considering it really has no symptoms (or treatment) I think I can safely rule that out. The sorbitol enzyme disorder is interesting as well. I’ve known, since Palmera was 3, she could not tolerate sorbitol. She ate some toothpaste once and had an immediate reaction – nausea within 5-10 minutes, followed by bad diarrhea an hour or so later. Still HFI resonates with me most because it explains the hypoglycemia. Also, it’s my understanding that sorbitol metabolizes to fructose which would explain her reaction to it.

I don’t think it is diabetes either (although her dad does have type II). If she had diabetes she would have hyperglycemia or high blood sugar, not low. Diabetics do become hypoglycemic but only after they start taking insulin or meds to bring blood sugar down. The meds are difficult to regulate and sometimes they lower blood sugar too much leading to diabetic hypoglycemia.

I have actually had very little help from her doctors thus far. Her pediatrician thinks nothing is wrong with her at all. Her GI is a better listener and put in an order for the DNA blood test at my request, but admits he really knows nothing about HFI. What liver enzymes do you get tested for and what kind of test is it?

She did have some metabolic tests run the second time she was in the ER with hypoglycemia. All came back normal.  ho They tested for acelcarnitine profile, insulin, and urine organic acids. Other than the insulin, I have no idea what those are, neither did her pediatrician. I was just told since all came back normal that I did not need to see a specialists, that some kids just get hypoglycemic when they get sick. When I mention that she was not sick (with a virus) the last time she was in the ER, I just get perplexed looks or blank stares.

Her ultrasounds do not show an enlarged liver. The kidneys  also looked normal, but one of the ducts was enlarged. Also there was thickening of the bladder wall indicating inflammation.

I will write more about her diet later. It’s such a long story, complicated by her low fodmap diet for fructose malabsorption, but I really would appreciate your feedback.

Thanks again,
Antonia

[colormist]

I'm not entirely certain which tests would show elevated liver levels. My doctor was shocked when she saw some of my results (I was having gallbladder issues and a fructose reaction at the same time), so I'll list the tests that had high results and hopefully you might be able get your doctor to perform a liver panel test.

Gamma GT -
This one was crazy elevated. The range was 7-50 U/L and my two results (a month apart) were 606 & 246. Both these results were after ingesting fructose (only once by accident).

Hepatic Function Panel (this tests several things: albumin, alkaline phosphatase*, bilirubin*, ast (sgot)*, alt (SGPT)*, and protein). -
I've asterisks the ones that were elevated after consuming fructose. This was also during a gallbladder attack, so keep that in mind. It might have been my gallbladder elevating the results and not the fructose. The gallbladder incident is separate issue from HFI.

My ultrasound also showed my liver was within normal limits (this test was done when I wasn't processing fructose). I did have blood in my urine (when I was processing fructose).

They're probably not going to see much of an issue with her liver if she's not in the midst of processing fructose (if she has HFI).

I hope you get your test results back soon!

[charlie]

Hi Antonia,

sorry I haven't been on for a while so not spotted your post. Welcome to the board.
Out of interest my daughter doesn't have HFI although I thought she did for years until the gene test came back negative and we looked down other paths. She has fructose malabsorption but also Congenital Sucrase-Isomaltase Deficency and she has frequent urination and kidney back pain. If she eats something she shouldn't she floods and has never been consistently dry at night often flooding heavily. She is now 12 and is finally starting to get some dry nights but the trick seems to be eliminating starch which is very hard to do. she has no extremely low fructose, no sucrose and very low starch and I give her some enzymes that help with general digestion as well as containing starch enzymes. She is better if she takes one with every meal.

What are your daughters other symptoms?

[antonia]

Hi,charlie. Glad to see you are active on this board. I ran into some of your past threads and have wondered about CSID also, but I never see hypoglycemia as a symptom for that. Did or does your daughter ever get hypoglycemic? (I suppose it would be very possible if she is unable to absorb fructose or break down starch.) My daughter's symptoms as of late include nausea, stomach pain (middle of belly, belly button level or lower), vomiting (when she gets really hypoglycemic), poor sleep, constant hunger, constipation, reflux and the urinary incontinence (sometimes worse than others). She has never been failure to thrive, always had a huge appetite despite her problems. Should also mention her growth has been slow this past year. She tested positive via breath test for fructose malabsorption at age three. From age 3 until now she has been on a low fodmap diet. Before low fodmap she had diarrhea, after low fodmap it changed to constipation. She did okay on the low fodmap diet after I learned I had to keep her serving sizes of fruits and vegetables very small and learned she could not tolerate brown rice, only white. When we challenged serving sizes of those low fodmap fruits and vegetables and started allowing some sucrose added foods in to her diet she started having problems again. And we learned she was becoming hypoglycemic after some recent trips to the ER. Should also mention something the dentist told me at age 3 leads me to believe she has been hypoglycemic before.  He said she had black stains on her teeth (not dental carries, just stains) like they see in their diabetic patients.  Said she had the mouth chemistry of a diabetic.  Diabetics on insulin do become hypoglycemic but I did not make that connection at the time.

Recently I changed to a version of a HFI diet. Currently she eats Cream of Rice, white rice, pasta (made from rice and corn), eggs, beef, pork, chicken, turkey, salmon, milk, cheese (all kinds as long as there are no additives), cottage cheese, plain greek yogurt, processed corn products (corn flakes, polenta, plain chips, tortilla), plain potato chips, tator tots, Brazilian cheese bread (tapioca flour based bread, no sugar), olives, spinach, cucumber, green beans, romaine lettuce, some spices (sage, parsley, thyme, black pepper, dill). She has vastly improved on this diet. From only being able to sit on the couch, puke bowl in hand, to rosy cheeks, sleeps well and rarely has nausea. I recently found a vitamin C supplement I think is safe to give her so now I will remove all vegetables. She still says stomach pain will come and go. I don't know if it's caused by fructose/sucrose or constipation though. Also has some reflux which in the past I've been able to control by giving her probiotics and relieving the constipation. Relieving constipation stops the reflux. Those probiotics have sugar though, so I stopped giving them to her. I've also stopped the tator tots as they seemed to make her nauseous the last time she ate them (they do have dextrose added, don't know if that could be the cause, heard it can be impure).

Sounds like you've had a long journey. How did you finally determine it was FM and CSID? In relation to CSID, I don't think my daughter has a problem with starch, but I suppose sucrose is a possibility. Prior to suspecting HFI, my daughter was scheduled for some GI tests, an endoscopy and SIBO breath test. Now that I suspect HFI I'm afraid to do those tests. The SIBO breath test involves giving her a lactulose sugar solution, not safe if she has HFI. And I'm afraid if she has the endoscopy they'll give her something with sucrose or sorbitol during the procedure. I've cancelled both those tests. I think the endoscopy could test for some of the enzymes involved in CSID though.

Would love to hear what you think. I would be nowhere without the help of people from these support groups and discussion boards.

Thanks,
Antonia

[antonia]

Colormist, first of all I hope your gallbladder issues are getting resolved and you're feeling better. Thank you for the liver enzyme info. So, this may be a stupid question, but those levels were measure via a blood draw?

Best,
Antonia

[colormist]

My gallbladder issues are much better now that it is no longer in my body! Surgery was a bit rough. Percocet actually caused me MORE pain than the surgery (which is completely opposite of what it's supposed to do). I ended up vomiting from the pain. After vomiting, I refused the Percocet and my doctor was indisposed to give me an alternative medication. When he finally did call, he talked about a medication he knew I couldn't take because it had sugar in it! He even said he knew I couldn't take it! I guess he was expecting me to say, "Oh, let's do it anyway! I completely want to vomit after having surgery on my stomach and I could do with some more pain in my kidneys."

Seriously, doctors--even when they KNOW what your condition is--are difficult to work with and you have to watch their every move.

The liver data was gather via blood test. They took a few vials and performed lots and lots of tests. The liver function test being one of them.

There's another test they can do that is a biopsy of the liver, but that one is very invasive.

I'm glad to hear that your daughter is doing better on the diet. It can be scary having a sick child and not knowing what to do to make it better.

One note: be sure to monitor her after cucumbers. Cucumbers do have a bit of unsafe sugars in them (you can see a breakdown here: nutritiondata.self.com/facts/vegetables-and-vegetable-products/2439/2 click "more details" under carbohydrates).
If you notice her having symptoms after ingesting cucumber, you might want to remove that from her diet. I'm not certain why dill pickles are okay and cucumbers aren't but that's just another instance of the HFI diet being really, really unpredictable.

[charlie]

Hi Antonia, yes hypoglycemia is a major problem for my daughter. She has a real phobia about needles so can't use a blood sugar monitor but she displays classic symptoms and has been hospitalised for it in the past. She wakes up every morning with low blood sugar and needs a hot milk to get her going followed by bacon and sausage breakfast. if she doesn't eat little and often then she will go into screaming rages, feels nauseous and fuzzy headed, blanks out and can pass out. I have learned over the years to manage it. I think it is an issue because they cannot absorb the sugars from their diet properly so once they have burnt off their reserves there is nothing left.

We diagnosed CSID by diet elimination in the end and the breakthrough was eliminating starch and using starch enzymes. Sucrose and fructose made her very sick, starch just made her lethargic and gassy. To save a long post have a look at a blog I have started, but not got very far with as my computer is so old it takes ages to do..... sugarfreelifeblog.wordpress.com/2014/11/09/a-long-11-year-search-for-answers/

In terms of diagnosis, yes the endoscopy tells you the levels of enzymes but we have done it very slowly by building up the diet and seeing what she can cope with. We are currently waiting to see a Geneticist to see if we can get the CSID one done.
Hope this helps. Unfortunately diagnosis is often little step by little step.

[antonia]

Thanks Charlie. Good for you in getting a blog up and running.

So, originally I was thinking CSID was not likely because Palmera does not get diarrhea from eating starch (or sugar, when she was eating it). However, I spoke with a mom on a fructose malabsorption support site yesterday whose daughter is also diagnosed with both FM and CSID and she said her daughter has been constipated since birth. Palmera had diarrhea or loose stools up until we put her on a low fodmap diet, then it changed to constipation. Don’t really know what that means, other than I just can’t rule anything out. The profiles we see in the literature don’t necessarily fit everybody.

I have a hard time telling when Palmera is hypoglycemic, her behavior and energy levels do change but it’s very subtle. She tends to want to cuddle, gets pale, or I just see it in her facial expressions, but I’m usually the only one who picks up on it. She is also very much a people pleaser, very conscious about being a “good girl”, and that may have something to do with it. The hospital staff has been so surprised how low her blood sugar is when we bring her in. One of the nurses’ remarked, after getting the results from her blood draw, “Wow, she is mentating so well, I never would have guessed.” A little girl with smiles for the doctors’ jokes concerned about finding the right movie on the TV and chatting about her favorite characters just does not read as sick, I guess. Also what I deal with at the pediatric office… The doctors there think I’m crazy.

Not to say we have not had our fare share of tantrums, she can be extremely emotional, but I’ve never been able to correlate her behavior to what she’s been eating or her immediate medical state as many moms seem to be able to do. I also suspect she may have been having minor seizures while sleeping. Due to being hypoglycemic?? I tried to catch this on video but was never able to. I knew if I had no proof her pediatrician would foo foo it.

I also think about glycogen storage disorders and I saw on your blog that you considered that as well. How did you rule that out? Genetic testing?

For now her energy levels on the HFI diet have been so great I feel I want to wait and see what the blood test reveals before I pursue other diagnosis. Her sleep has also been amazing. She used to wake several times a night, thrash around a lot, cry out and whimper. When I would ask what was wrong, why she could not sleep, she would just say she did not know. I slept in her room almost every night on the floor. It was just easier to be there to comfort her. I have been in my own bed now for the last couple weeks. Amazing. Should be beneficial to my marriage as well.

[antonia]

Colormist, glad to hear the gallbladder can no longer cause you problems! I can only imagine how much more stressful it is to deal with an already stressful situation by having to explain HFI to your doctors. It's even difficult to communicate with them about fructose malabsorption. When Palmera was in the hospital they told me they had dieticians on staff that understood the low fodmap diet but when they brought her meals it was clear that they did not... Grrr. Also had to put a stop to them giving her oral, anti nausea meds that I'm sure contained sugar or sorbitol. They just don't seem to get it.

I see what you mean about cucumbers and see similar data for romaine lettuce as well. I've actually removed all vegetables for now. I'm giving her a vitamin C supplement and now that I see the overall improvement in removing them all together I'm getting over my trepidations about it.

[christopher]

Jun 16, 2015 15:33:34 GMT -5 antonia said:

Should also mention something the dentist told me at age 3 leads me to believe she has been hypoglycemic before.  He said she had black stains on her teeth (not dental carries, just stains) like they see in their diabetic patients.  Said she had the mouth chemistry of a diabetic.  Diabetics on insulin do become hypoglycemic but I did not make that connection at the time.

This is a strange coincidence or perhaps it is not. I also suspect I have FBPase deficiency, and I also get these black stains on my teeth. Especially along the edges where the teeth meet the gum will stain black. I have to have the discoloration removed by a professional at regular intervals, but it usually comes back. I´ve had them for years. 

Have you ever considered that your child might have FBPase deficiency as well as Fructose malabsorption? Just a thought...

[antonia]

Well, you are the first person who has ever told me that they share the teeth staining trait with my daughter. I do strongly consider FBPase Deficiency in addition to HFI. But I can go back and forth, back and forth between the two forever, mulling over my daughter's history, and never come to a conclusion either way. She shares many traits with HFIers, but there have also been many instances where I feel she's consumed too much fructose and not gotten sick from it to believe she could have HFI.

Through our local, children's hospital we have had partial gene testing done for both HFI and FBPase Deficiency. Both tests have come back negative. Only the sequencing portion of these tests were performed however. Based on the negative result of the sequencing tests they do not feel that the deletion/duplication portions of the tests are warranted. They do not believe my daughter has a biochemical disorder. So I have been left to work this out on my own.

Currently I am working on getting a blood sample to Dr. Tolan's lab for complete HFI gene analysis. I will feel better about the results knowing that Dr. Tolan is the expert on this kind of analysis. I have heard at least one person say they initially got a negative result from their HFI test, then the test being done again using different parameters and ending up with a positive result! So there must be room for error in this kind of analysis somewhere.

If my daughter's HFI test comes back negative through Dr. Tolan then I suppose we'll look into FBPase Deficiency analysis at an outside lab of some kind. Reality is that these DNA tests are not diagnostic and we may never get our answer through them. In your research, if you ever come across other indicators of FBPase Deficiency, besides DNA, do let me know! Or if you find a researcher with expertise in FBPase Deficiency, along the lines of what Dr. Tolan is to HFI, I would be all over that. These are frustrating diseases to diagnose for sure.

[lucky]

Antonia,

Perhaps your metabolic team might consider an in-hospital "Fasting Test".

My son had this test after his genetic testing came back negative. There are 4 metabolic disorders that do not do well under fasting situations... one of which involves fructose issues (FBPase deficiency). This test can give needed metabolic results.

[christopher]

Antonia,

I just read your first post again. From time to time I also have the urge to urinate very frequently, although there might not be all that much urine to actually pass. Never been able to figure out why these sensations appear from time to time.

If I can speculate a little, based on what I´ve read about FBPase deficiency, I have a hypothesis as to why it might cause renal damage.
From what I know: In FBPase deficiency the lacking enzyme causes fructose-1,6-biphosphate to accumulate instead of being converted to the next normal intermediate product in the glycolytic or the gluconeogenic pathway. But, the fructose-1,6-biphosphate can still be converted to lactate by way of another enzyme we´re not deficient in. This can cause lactic acidosis - an accumulation of lactate and H+ ions in the blood, the latter of which is what is actually causing the acidosis. How much lactate that accumulates will in my understand depend on how deficient the person is in FBPase and how much noxious sugars that have been ingested. If the lactate and H+ ions accumulate enough, I believe this will cause a sensation in the body, just like when muscles tire/stiffen from exhaustion/exercise. I know I have had these sensations in the past, but have never realized why it might be until just recently.

I believe a person with FBPase deficiency has two different ways to remove the accumulated lactate from the body: 1) lactate can be used directly by the muscles as a fuel source - meaning we might be able to "walk it off" or exercise it off in other ways. Or, 2) the excess lactate is filtered from the blood by the kidneys and passed into the urine. I have no idea if this is correct, but I have noticed in the past that my urine has smelled quite sweet but not fruity, rather it has smelled more like porridge made with milk. Not sure the sugar lactate has a smell, but I suppose it might be easy to find out, and it would make a lot of sense.
2) is what I believe might cause the renal damage.

I will have to talk to a doctor about this, but I believe this peculiar trait of FBPase deficiency can make challenge tests a safer than for those with regular HFI. If you can keep a steady supply of glucose to the body while challenging the liver by ingesting pure fructose, I believe this will cause some degree of lactic acidosis - similar to what you get from intensive exercise - without the hypoglycemia. If so, the lactate can be measured with a device similar to blood glucose meters that diabetics use, but for measuring lactate. A lot of running coaches and swimming coaches have these devices. They´re very expensive to buy, but quite cheap to use if you could borrow one.

Of course, if one were to have something else than FBPase deficiency, or something else in addition to it, that might make this a terrible idea! Even if that is not the case either, lactic acidosis from other causes than exercise is associated with a very high likelihood of death. Just to be clear for everyone : DO NOT TRY THIS on your own! If you mess up you might kill yourself/the person doing the challenge.

Antonia - have you ever noticed your child hyperventilating - either by breathing very quickly or taking very deep breaths, or even sighing from time to time?

[antonia]

Lucky, we were pretty much shown the door by our metabolic team. Had received an email stating the FBPase test was negative and we should, therefore, cancel any follow up appointments.

A couple days later, after receiving that email, we ended up in the ER with hypoglycemia. Palmera was fighting some kind of illness and we could not stop the hypo from occurring. While we were there, the ER doc spoke with a different genetic doctor, on call at the time, and he told us that he would see us. We see him in March. I hope he will take the time to listen and be more investigative than our previous doctor. But I'm not holding my breath. Since, other than the hypoglycemia, her labs show up normal and because we manage her diet so well at home there is nothing for doctors to "see". They basically don't believe there is anything metabolically wrong with her.