You may be asked to give a biopsy sample in order to determine your condition. Before you surrender to this option be very aware that a biopsy could kill you and will in no way improve your level of care. There is quite a fair amount of pressure at the kidneys in the blood. Increased blood pressure can damage the kidneys. Infections also can damage the kidneys but are treatable with antibiotics. The safest way forward is to ask your GP to give you antibiotics making sure that you are not allergic to them of course. Explain to your Doctor that you want to do this because it is far safer than having a biopsy and less likely to cause irreparable damage to a kidney than a biopsy.
Another possibility that has not been addressed is that your kidneys might be performing a little too well and more toxins are leaving your body via your bladder than normal. Best to get a blood test in order to determine the levels of toxins in your blood to see if there is a serious problem.
However, it can be normal for people to have frothy urine from time to time and I suspect that dietary changes could explain some of these intermittent episodes.
I also have frothy urine and have had for 2 years now, but not all the time, some times a week can pass and none, other times it looks like ive drank a small amount of washing up liquid. My own problem was caused by drinking bottled water with high levels of salt in it, which raised my blood pressure.
Some bottled waters are far more mineral-intense than others - you can often taste this. But even if the water contains the minerals our bodies need - such as calcium or magnesium - it's unlikely to make a positive impact on your health in any big way, as the quantities are usually so small.
The only exceptions are some of the 'fortified with calcium' waters, such as Danone. Otherwise, depending on where you live, you can glean more calcium from tap water than from bottled water. The key is whether the water has filtered through the rocks, as this is how it picks up the calcium.
My biggest concern over bottled waters is that some of them contain excessive levels of sodium (one of the constituents of salt). This can be a problem if you have high blood pressure, which can be exacerbated by too much salt in the diet.
This may come as a surprise to those who are carefully watching their salt intake in food - but the fact is, you can be blissfully drinking your water, thinking it's doing your blood pressure good, but find it isn't getting any better - and that's because of the salt in the water.
Admittedly this is a rare scenario, as usually people who drink lots of water expel much of the sodium it contains in their urine. However, higher sodium intake is not good for anyone whose body is not efficient in getting rid of excess salt, or who has a problem such as high blood pressure or kidney disease.
It's also not a good idea if you have low bone density (excess salt increases the rate at which the bones lose calcium) or suffer from fluid retention as a result of PMShttp://www.dailymail.co.uk/pages/live/articles/health/janeclarke.html?in_article_id=495110&in_page_id=1988&in_a_source=
I also ate lots of avocado which contain a very lethal toxin called percin which is known to damage kidneys. I also loved to eat grapefruit, again not wisehttp://www.thenakedscientists.com/forum/index.php?topic=2004
Avocadoes Google: persin avocado
Avocado "can be dangerous to our animal companions. "Avocado leaves, fruit, seeds, and bark contain a toxic principle known as percin"... The primary concern with dogs is with gastrointestinal irritation, including vomiting and diarrhea... Birds and rodents appear to be particularly sensitive to avocado, and ingestion can result in respiratory distress, congestion, fluid accumulation around the heart, and even death" (Newsletter, ASPCA, Oct. 14, 2005).