Stone formation:

Causes and preventive measures

In spite of various health precautions some of us still develop stones. This is often due to misinformation. Certain myths such as drinking water excessively would prevent formation of stones, instead could increase the chances.

Fortunately due to advances in medical technology in 95% of the cases, the stones can be removed without large incisions.

Healthwise spoke to Prof. Neville D. Perera, Consultant Urological Surgeon, Department of Urology and Renal Transplantation, National Hospital on the causes, symptoms and treatment for stones.

Stones can develop in many parts of the body. Those that form in the kidneys,gall bladder and pancreas cause many symptoms and complications. "Kidney and gallstones are the most common forms of stones. "Kidney stones are a major problem in many developing countries such as Sri Lanka," said Prof. Perera.

He explained that the fact most men are susceptible to kidney and gallstones, has little to do with anatomy. "Except for the fact that they experience comparatively more pain due to narrower and longer male urinary tract," explained Prof. Perera. However, he said that men are susceptible to kidney and gallstones because they work in a dry climate and are frequently subjected to dehydration, which is a major cause of stone formation.

Myths

Contrary to popular belief, hard water high in calcium, consumed in some areas of the country, does not cause stones, explained Prof. Perera. "It is purified when it passes through the stomach." Prof. Perera explained that drinking water excessively does not prevent formation of stones. "In fact recent studies show that if a person drinks more than four litres of water a day it increases the chances of getting stones." The recommended total liquid consumption per day of a normal person is 2.5 or three litres on a hot day.

No direct relationship between soft drinks, alcohol and smoking and stones has been found. Calcium supplements and high calcium milk products if taken with meals does not lead to stone formation.

"Most patients pass the stone with urine and claim that the stone has been dissolved", said Prof. Perera. "This is not possible in western medicine, in fact there is no conclusive scientific evidence that this can be done."

Causes

Four major causes contribute to the formation of stones explained Prof. Perera. When a small crystal of stone is formed and does not get flushed out of the urinary tract it could get bigger. Stones are composed of phosphate, carbon or calcium oxalate - the most common element. "These crystals can form due to high calcium or oxalate in urine caused by large amounts of calcium and oxalates in diet. Fortunately it is not a common problem in developing countries," explained Prof. Perera.

Dehydration due to low water intake could predispose someone to develop calcium and oxalate crystals. He explained that this could be clearly observed in the dry regions of the country.

Another mechanism of stone formation is having a block or obstruction of the urinary tract, which - in children - could result from the narrowing of ureters due to a birth defect or obstruction to the bladder by prostrate gland in adults.

Increased secretion of parath hormone by the parathyroid glands, which leads to high levels of blood calcium, can lead to stones.

Foreign bodies such as bacteria and cells in the urinary tract can act as a centre point for the formation of a stone. "There is a saying 'all bladder stones are tomb stones of bacteria', said Prof. Perera.

Symptoms

Prof. Perera explained that once a kidney stone forms it tries to come out through the urinary tract while it is still small. The signature 'loin to groin pain' - a pain which starts from the loin area and runs towards the groin - is caused by the 'rolling down' of the stone through ureter to bladder. Popularly known as 'renal colic' this pain is only second to pain in child birth. "This is often accompanied by vomiting, nausea, faintness and sweating."

If the stone is in the kidney or urinary bladder and not moving, symptoms differ significantly. A dull ache is felt in the loin area or lower abdomen if the stone is in kidney or bladder and blood mixed in urine due to scratching of tissue. "If the stone is infected with bacteria these symptoms can be accompanied by signs of urine infection, such as a burning sensation while passing urine, fever, chills and shivering."

When a stone is suspected

The existence of a stone can be confirmed by way of a simple X-ray.

However, Prof. Perera explained that, X-ray detection requires calcium as a constituent. "Ten percent of stones are not detected by X-ray because they are made up of uric acid," in which case X-ray has to be combined with ultrasound scan to show the situation of the kidneys.

If the kidneys show signs of blockage or infection physicians have to resort to special X-ray methods such as IVU (Intravenous Urogram) or CT scan. "These tests involve injecting a special radioactive dye and will provide details of the state of the kidneys."

Treatment

The treatment depends on the size, the location of the stone and symptoms and complications caused. "Not all stones require active treatment or removal," said Prof. Perera. Small stones less than five millimeters in the kidney, which do not cause discomfort to the patient or damage the kidney can be kept under observation. "All that's needed is to keep an on the situation with annual ultrasounds and X-rays.

There is a 90% chance that stones less than 5 mm will find their way out in a matter of weeks." The stones which are 'moving' can also be kept under observation. Prof. Perera said that there are now new drugs that relax and expand the urethra (water pipe) and speed up the passage of these stones. "But these drugs should always be taken under a physician's advice since they could trigger side effects", warned Prof. Perera.

If the stone gets bigger and , does not show signs of passing or causes complications they require removal. Prof. Perera explained that larger stones which are in the middle of the kidney ureter or bladder require active treatment.

Prof. Perera explained that less than three decades ago such stones were removed through open surgeries that involved a large cut in the abdomen resulting in a life long scar. The cut itself leading to a lot of complications such as infections, pain, bleeding and bad cosmetic effects, especially in young people.

Fortunately, due to advances in medical technology within the last two and half decades most stones can be removed without such large incisions. ESWL or Extra-corporeal Shock Wave Lithotripsy is a revolutionary stone crushing method, where a special sound wave is sent into the body.

Prof. Perera explained that most kidney stones which are less than 2 cm can be crushed into tiny pieces within a half hour session of ESWL without general anesthesia, as a day procedure or in-and-out procedure. "No overnight stay is required, only a painkiller is needed to counteract the pain produced by passage of tiny pieces with urine."

Prof. Perera assured that complications resulting from this procedure - such as passing blood with urine and infections - are rare and repetition up to three times is safe. "Because there is a slight chance that the kidney might get damaged." He said that the procedure is safe enough to be used on children, but should be avoided on pregnant women, or as a method of which to crush large or hard stones.

Patients have to undergo 'keyhole surgery' if the stone is too large or hard to be crushed. Medically known as PCNL (Percutaneous Nephrolithotripsy) this involves the introduction of a small telescopic instrument - the size of a pencil - into the kidney through the water pipe or a direct puncture made in the loin under general anesthesia.

The procedure of introducing the telescopic instrument through the urinary tract is known as URS (Ureterorenoscopy). Once the stone is detected through the fibreoptic, it is crushed into powder, allowing it to get flushed out with urine later on.These methods require special instruments and trained urological surgeons to perform the surgery. Ninety-five percent of stones can be removed by these methods without resorting to large incisions, explained Prof. Perera.

He explained that surgeons resort to open surgery in less than five percent of the cases, such as in the case of stag horns - very large stones - or if the kidney is none functioning.

Dangers and complications

"Stones can block the ureters and kidneys," explained Prof. Perera.

Once the kidney is blocked it will stop the filtering of urine. "If both kidneys are blocked it could lead to kidney failure." Infections caused by bacteria in the stones could lead to the destruction of the kidneys. Large stones left unattended for a long period can lead to the destruction of the bladder.

Prevention

If a patient is regularly subject to stones, he or she may require special drugs. Prof. Perera explained that this is necessary only in the case of a birth defect that would require lifelong treatment.

Occasionally, certain diseases in parathyroid glands, which causes an increased secretion of the parath hormone leads to high blood calcium levels, resulting in repeated stone formation. "This will require a parathyroidectomy - removal of effected parathyroid gland(s)."

He explained that if all four glands are removed the patient must take a calcium supplement.

"Consume an adequate amount of water to prevent dehydration and seek medical advice as soon as symptoms manifest in order to avoid complications.

-SP

Gel cuts HIV-infections by half

A vaginal gel has significantly cut the rate of women contracting HIV from infected partners in an experiment in South Africa, researchers said.

They said the gel, containing Aids drug tenofovir, cut infection rates among 889 women by 50% after one year of use, and by 39% after two and a half years.

If the results are confirmed it would be the first time that a microbicidal gel has been shown to be effective.

Such a gel could be a defence for women whose partners refuse to wear condoms.

New ways of curbing the spread of HIV are badly needed, particularly in sub-Saharan Africa, where nearly 60% of those infected with the virus are women.

Many women are often forced to take part in unsafe sex, and are biologically more vulnerable to HIV infection than men, making a gel they apply an attractive option.Welcoming the results, UN agencies said they would convene an expert consultation in South Africa next month to discuss the next steps with the product.

'Just pennies' The results of the three-year study, which was completed by the Centre for the Aids Programme of Research in South Africa (Caprisa), are being presented at an international aids conference in Vienna and were published on Monday by the US magazine Science.

The gel was found to be both safe and acceptable when used once in the 12 hours before sex and once in the 12 hours after sex by women aged 18 to 40 years.

Salim Abdool Karim, one of the two leading co-researchers, told reporters in Vienna that the 889 women involved in the trial, conducted in the coastal city of Durban and a remote rural village, had largely used the gel as directed.

They were also given condoms and advice about sexually transmitted diseases, and tested for HIV once a month.

After 30 months, 98 women became infected with HIV - 38 in the group that got tenofovir in the gel and 60 in the group that got placebos.

"We showed a 39% lower incidence of HIV in the tenofovir group," Dr Karim said.

Tenofovir, he added, lowered the risk of infection by 50% at 12 months but then the efficacy declined.

Women who used the gel more consistently were much less likely to be infected, he said.

He added that he did not know how much each dose would cost but said the applicators and gel cost "just pennies".

"Boy, have we been doing the happy dance," Dr Karim, from the University of KwaZulu-Natal in Durban, said.

'Hope for women' "It's the first time we've ever seen any microbicide give a positive result that you could say was statistically significant," said Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

The researchers say women who used the gel also showed a significant reduction in genital herpes, a common sexually transmitted infection, which itself increases the risk of HIV infection.

The UN's HIV /AIDSagency noted that nearly 20 years of research had gone into microbicides that can be controlled by a woman, independent of her partner.

"We are giving hope to women," said Michel Sidibe, executive director of UNAids.

"For the first time we have seen results for a woman-initiated and controlled HIV prevention option." A microbicide, he said, would be a "powerful option for the prevention revolution and help us break the trajectory of the Aids epidemic".

Dr Margaret Chan, director-general of the World Health Organisation, welcomed Caprisa's findings.

"We look forward in seeing these results confirmed," she said.

"Once they have been shown to be safe and effective, WHO will work with countries and partners to accelerate access to these products."

- BBC

[Health News]

Innovations in weight loss surgery

Dr. Brian Quebbemann, surgical director at The N.E.W. Program weight-loss centre in Newport Beach and TransEnterix, Inc. have teamed up to develop the Spider surgical tool, which allowed surgeons to perform bariatric surgery without the typical surgical incision.

The tool enters through a small hole made in the belly button and cuts down the capacity of the stomach, by up to 80 percent.

Approved by the FDA last year, the Spider has multiple instrument channels, allowing the surgeon to insert flexible instruments to expand the abdomen (kind of like an umbrella), minuscule cameras to view the working environment, and surgical tools to trim the stomach and make sutures. The Spider is then removed through the same hole.

Also on the horizon, and currently in a multi-centrestudy to gain FDA approval, is the TOGA System, a less-invasive bariatric procedure that is performed endoscopically (through the mouth).

A set of flexible devices is inserted through the mouth into the stomach to staple together sections of the stomach and thus reduce its overall food capacity.

The TOGA System is a set of flexible stapling devices that is inserted through the mouth into the stomach. Once the device is in place, suction is used to gather together tissue from both sides of the stomach into the device. The collected tissue is then fastened together with titanium staples.

The procedure creates a small stomach pouch, shaped like a narrow sleeve, at the top of the stomach. Once the stomach is stapled and the procedure is complete, the device is removed from the body.

If you are looking for a weight loss plan that does not include any type of surgery, visit the HealthNews diet pages and test out our Individual Diet Selection tool, which can help find the right diet for you lifestyle.

- Healthnews