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Urinary tract infection (UTI)

OTHER  NAMES: Acute cystitis or Bladder infection,

Definition:
A urinary tract infection (UTI), is an infection that affects part of the urinary tract.(kidneys, ureters, bladder and urethra.) Most infections involve the lower urinary tract — the bladder and the urethra.When it affects the lower urinary tract it is known as a simple cystitis (a bladder infection) and when it affects the upper urinary tract it is known as pyelonephritis (a kidney infection). …..CLICK & SEE… :Female urinary system .……. Male urinary system 

Women are at greater risk of developing a UTI than men are. Infection limited to your bladder can be painful and annoying. However, serious consequences can occur if a UTI spreads to kidneys.

CLICK &  SEE THE PICTURES

Doctors typically treat urinary tract infections with antibiotics. But you can take steps to reduce your chances of getting a UTI in the first place.

SIGN  &  SYMPTOMS:   
Urinary tract infections don’t always cause signs and symptoms, but when they do they may include:

*A strong, persistent urge to urinate
*A burning sensation when urinating
*Passing frequent, small amounts of urine
*Urine that appears cloudy
*Urine that appears red, bright pink or cola-colored — a sign of blood in the urine
*Strong-smelling urine
*Pelvic pain, in women — especially in the center of the pelvis and around the area of the pubic bone

UTIs may be overlooked or mistaken for other conditions in older adults.

Types of urinary tract infection:

Each type of UTI may result in more-specific signs and symptoms, depending on which part of your urinary tract is infected.

These symptoms may vary from mild to severe and in healthy persons last an average of six days.

KIDNEYS (acute pyelonephritis):...CLICK & SEE
*Upper back and side (flank) pain
*High fever
*Shaking and chills
*Nausea
*Vomiting

BLADDER (cystitis): ….CLICK & SEE
*Pelvic pressure
*Lower abdomen discomfort (Some pain above the pubic bone or in the lower back may be present.)
*Frequent, painful urination
*Blood in urine (Rarely the urine may appear bloody  or contain visible pus in the urine.)

URETHRA (urethritis): …….CLICK & SEE
:Burning with urination
:Discharge

Children:
In young children, the only symptom of a urinary tract infection (UTI) may be a fever. Because of the lack of more obvious symptoms, when females under the age of two or uncircumcised males less than a year exhibit a fever, a culture of the urine is recommended by many medical associations. Infants may feed poorly, vomit, sleep more, or show signs of jaundice. In older children, new onset urinary incontinence (loss of bladder control) may occur.

Elderly:
Urinary tract symptoms are frequently lacking in the elderly. The presentations may be vague with incontinence, a change in mental status, or fatigue as the only symptoms, while some present to a health care provider with sepsis, an infection of the blood, as the first symptoms. Diagnosis can be complicated by the fact that many elderly people have preexisting incontinence or dementia.

It is reasonable to obtain a urine culture in those with signs of systemic infection that may be unable to report urinary symptoms, such as when advanced dementia is present. Systemic signs of infection include a fever or increase in temperature of more than 1.1 °C (2.0 °F) from usual, chills, and an increase white blood cell count.

CAUSES:    
Urinary tract infections typically occur when bacteria enter the urinary tract through the urethra and begin to multiply in the bladder. Although the urinary system is designed to keep out such microscopic invaders, these defenses sometimes fail. When that happens, bacteria may take hold and grow into a full-blown infection in the urinary tract.

The most common UTIs occur mainly in women and affect the bladder and urethra.

E. coli is the cause of 80–85% of community-acquired urinary tract infections, with Staphylococcus saprophyticus being the cause in 5–10%. Rarely they may be due to viral or fungal infections. Healthcare-associated urinary tract infections (mostly related to urinary catheterization) involve a much broader range of pathogens including: E. coli (27%), Klebsiella (11%), Pseudomonas (11%), the fungal pathogen Candida albicans (9%), and Enterococcus (7%) among others. Urinary tract infections due to Staphylococcus aureus typically occur secondary to blood-borne infections. Chlamydia trachomatis and Mycoplasma genitalium can infect the urethra but not the bladder. These infections are usually classified as a urethritis rather than urinary tract infection

Sex:
In young sexually active women, sexual activity is the cause of 75–90% of bladder infections, with the risk of infection related to the frequency of sex. The term “honeymoon cystitis” has been applied to this phenomenon of frequent UTIs during early marriage. In post-menopausal women, sexual activity does not affect the risk of developing a UTI. Spermicide use, independent of sexual frequency, increases the risk of UTIs. Diaphragm use is also associated. Condom use without spermicide or use of birth control pills does not increase the risk of uncomplicated urinary tract infection.

Women are more prone to UTIs than men because, in females, the urethra is much shorter and closer to the anus. As a woman’s estrogen levels decrease with menopause, her risk of urinary tract infections increases due to the loss of protective vaginal flora. Additionally, vaginal atrophy that can sometimes occur after menopause is associated with recurrent urinary tract infections.

Chronic prostatitis may cause recurrent urinary tract infections in males. Risk of infections increases as males age. While bacteria is commonly present in the urine of older males this does not appear to affect the risk of urinary tract infections.

Urinary catheters:
Urinary catheterization increases the risk for urinary tract infections. The risk of bacteriuria (bacteria in the urine) is between three to six percent per day and prophylactic antibiotics are not effective in decreasing symptomatic infections. The risk of an associated infection can be decreased by catheterizing only when necessary, using aseptic technique for insertion, and maintaining unobstructed closed drainage of the catheter.

Male scuba divers utilizing condom catheters or the female divers utilizing external catching device for their dry suits are also susceptible to urinary tract infections.

Others:
A predisposition for bladder infections may run in families. Other risk factors include diabetes, being uncircumcised, and having a large prostate. Complicating factors are rather vague and include predisposing anatomic, functional, or metabolic abnormalities. In children UTIs are associated with vesicoureteral reflux (an abnormal movement of urine from the bladder into ureters or kidneys) and constipation.

Persons with spinal cord injury are at increased risk for urinary tract infection in part because of chronic use of catheter, and in part because of voiding dysfunction. It is the most common cause of infection in this population, as well as the most common cause of hospitalization. Additionally, use of cranberry juice or cranberry supplement appears to be ineffective in prevention and treatment in this population.

Pathogenesis:
The bacteria that cause urinary tract infections typically enter the bladder via the urethra. However, infection may also occur via the blood or lymph. It is believed that the bacteria are usually transmitted to the urethra from the bowel, with females at greater risk due to their anatomy. After gaining entry to the bladder, E. Coli are able to attach to the bladder wall and form a biofilm that resists the body’s immune response.

RISK FACTORS  &  COMPLICATIONS:
*Urinary tract abnormalities. Babies born with urinary tract abnormalities that don’t allow urine to leave the body normally or cause urine to back up in the urethra have an increased risk of UTIs.

*Blockages in the urinary tract. Kidney stones or an enlarged prostate can trap urine in the bladder and increase the risk of UTIs.
A suppressed immune system. Diabetes and other diseases that impair the immune system — the body’s defense against germs — can increase the risk of UTIs.

*Catheter use. People who can’t urinate on their own and use a tube (catheter) to urinate have an increased risk of UTIs. This may include people who are hospitalized, people with neurological problems that make it difficult to control their ability to urinate and people who are paralyzed.

*A recent urinary procedure. Urinary surgery or an exam of your urinary tract that involves medical instruments can both increase your risk of developing a urinary tract infection.
When treated promptly and properly, lower urinary tract infections rarely lead to complications. But left untreated, a urinary tract infection can have serious consequences.

Complications of a UTI are as follows::

*Recurrent infections, especially in women who experience three or more UTIs.
*Permanent kidney damage from an acute or chronic kidney infection (pyelonephritis) due to an untreated UTI.
*Increased risk in pregnant women of delivering low birth weight or premature infants.
*Urethral narrowing (stricture) in men from recurrent urethritis, previously seen with gonococcal urethritis.
*Sepsis, a potentially life-threatening complication of an infection, especially if the infection works its way up to urinary tract to the kidneys.

DIAGNOSIS:
In straightforward cases, a diagnosis may be made and treatment given based on symptoms alone without further laboratory confirmation. In complicated or questionable cases, it may be useful to confirm the diagnosis via urinalysis, looking for the presence of urinary nitrites, white blood cells (leukocytes), or leukocyte esterase. Another test, urine microscopy, looks for the presence of red blood cells, white blood cells, or bacteria. Urine culture is deemed positive if it shows a bacterial colony count of greater than or equal to 103 colony-forming units per mL of a typical urinary tract organism. Antibiotic sensitivity can also be tested with these cultures, making them useful in the selection of antibiotic treatment. However, women with negative cultures may still improve with antibiotic treatment. As symptoms can be vague and without reliable tests for urinary tract infections, diagnosis can be difficult in the elderly.

Classification:
A urinary tract infection may involve only the lower urinary tract, in which case it is known as a bladder infection. Alternatively, it may involve the upper urinary tract, in which case it is known as pyelonephritis. If the urine contains significant bacteria but there are no symptoms, the condition is known as asymptomatic bacteriuria. If a urinary tract infection involves the upper tract, and the person has diabetes mellitus, is pregnant, is male, or immunocompromised, it is considered complicated. Otherwise if a woman is healthy and premenopausal it is considered uncomplicated. In children when a urinary tract infection is associated with a fever, it is deemed to be an upper urinary tract infection.

Children:
To make the diagnosis of a urinary tract infection in children, a positive urinary culture is required. Contamination poses a frequent challenge depending on the method of collection used, thus a cutoff of 105 CFU/mL is used for a “clean-catch” mid stream sample, 104 CFU/mL is used for catheter-obtained specimens, and 102 CFU/mL is used for suprapubic aspirations (a sample drawn directly from the bladder with a needle). The use of “urine bags” to collect samples is discouraged by the World Health Organization due to the high rate of contamination when cultured, and catheterization is preferred in those not toilet trained. Some, such as the American Academy of Pediatrics recommends renal ultrasound and voiding cystourethrogram (watching a person’s urethra and urinary bladder with real time x-rays while they urinate) in all children less than two years old who have had a urinary tract infection. However, because there is a lack of effective treatment if problems are found, others such as the National Institute for Health and Care Excellence only recommends routine imaging in those less than six months old or who have unusual findings.

Differential diagnosis:
In women with cervicitis (inflammation of the cervix) or vaginitis (inflammation of the vagina) and in young men with UTI symptoms, a Chlamydia trachomatis or Neisseria gonorrheae infection may be the cause. These infections are typically classified as a urethritis rather than a urinary tract infection. Vaginitis may also be due to a yeast infection. Interstitial cystitis (chronic pain in the bladder) may be considered for people who experience multiple episodes of UTI symptoms but urine cultures remain negative and not improved with antibiotics. Prostatitis (inflammation of the prostate) may also be considered in the differential diagnosis.

Hemorrhagic cystitis, characterized by blood in the urine, can occur secondary to a number of causes including: infections, radiation therapy, underlying cancer, medications and toxins. Medications that commonly cause this problem include the chemotherapeutic agent cyclophosphamide with rates of 2 to 40%. Eosinophilic cystitis is a rare condition where eosinophiles are present in the bladder wall. Signs and symptoms are similar to a bladder infection. Its cause is not entirely clear; however, it may be linked to food allergies, infections, and medications among others.

TREATMENTS;
Medications:
For those with recurrent infections, taking a short course of antibiotics when each infection occurs is associated with the lowest antibiotic use. A prolonged course of daily antibiotics is also effective. Medications frequently used include nitrofurantoin and trimethoprim/sulfamethoxazole (TMP/SMX). Methenamine is another agent used for this purpose as in the bladder where the acidity is low it produces formaldehyde to which resistance does not develop. Some recommend against prolonged use due to concerns of antibiotic resistance.

In cases where infections are related to intercourse, taking antibiotics afterwards may be useful. In post-menopausal women, topical vaginal estrogen has been found to reduce recurrence. As opposed to topical creams, the use of vaginal estrogen from pessaries has not been as useful as low dose antibiotics. Antibiotics following short term urinary catheterization decreases the subsequent risk of a bladder infection. A number of vaccines are in development as of 2011.

Children:
The evidence that preventative antibiotics decrease urinary tract infections in children is poor. However recurrent UTIs are a rare cause of further kidney problems if there are no underlying abnormalities of the kidneys, resulting in less than a third of a percent (0.33%) of chronic kidney disease in adults. Whether routine circumcisions prevents UTIs has not been well studied as of 2011.

Alternative medicine:
Some research suggests that cranberry (juice or capsules) may decrease the number of UTIs in those with frequent infections. A Cochrane review concluded that the benefit, if it exists, is small. Long-term tolerance is also an issue with gastrointestinal upset occurring in more than 30%. Cranberry juice is thus not currently recommended for this indication. As of 2011, intravaginal probiotics require further study to determine if they are beneficial.

Lifestyle and home remedies:

Urinary tract infections can be painful, but you can take steps to ease your discomfort until antibiotics treat the infection.
The following tips should be followed:

*Drink plenty of water. Water helps to dilute your urine and flush out bacteria.

*Avoid drinks that may irritate the bladder. Avoid coffee, alcohol, and soft drinks containing citrus juices or caffeine until your infection has cleared. They can irritate the bladder and tend to aggravate frequent or urgent need to urinate.

*Use a heating pad. Apply a warm, but not hot, heating pad to your abdomen to minimize bladder pressure or discomfort.
PREVENTIONS:
The following steps can be taken to reduce the risk of urinary tract infections:

*Drink plenty of liquids, especially water. Drinking water helps dilute your urine and ensures that you’ll urinate more frequently — allowing bacteria to be flushed from your urinary tract before an infection can begin.

*Drink cranberry juice. Although studies are not conclusive that cranberry juice prevents UTIs, it is likely not harmful.

*Wash  or  Wipe properly   from front to back. Doing so after urinating and after a bowel movement helps prevent bacteria in the anal region from spreading to the vagina and urethra.

*Empty the bladder soon after intercourse. Also, drink a full glass of water to help flush bacteria.

*Avoid potentially irritating feminine products. Using deodorant sprays or other feminine products, such as douches and powders, in the genital area can irritate the urethra.

*Change the birth control method. Diaphragms, or unlubricated or spermicide-treated condoms, can all contribute to bacterial growth.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
https://en.wikipedia.org/wiki/Urinary_tract_infection
http://www.mayoclinic.org/diseases-conditions/urinary-tract-infection/

Baby Development & Care from Birth to Three Months

It is very difficult to know  what a newborn baby is capable of. In the early days and weeks after birth, to the naked eye, not much. Eating, crying, sleeping, and pooping seem to take up the majority of her day, with a few moments of alertness thrown in for good measure. But recent research has shown that she’s doing a lot more than that. “Even in the first minutes of life, babies are a wonder,” says Naomi Steiner, MD, a developmental and behavioral pediatrician at Tufts-New England Medical Center, in Boston. “The newborn has a superactive brain and is primed to learn.”
CLICK & SEE….>..….(1)….……....(2)
Recent research, much of which relies on high-tech advances in intrauterine photography and brain imaging, now offers empirical proof of what parents have known all along: Babies are smart. What’s more, each baby is born with a unique personality that becomes readily apparent within the first few weeks of life. “Babies come into the world as themselves,” says Dr. Steiner. “It’s our job to get to know them.”

Baby’s Ability

Even though your baby can’t care for herself, what she is capable of at birth may surprise you. She’s born with 70 innate reflexes designed to help her thrive, some of which are truly remarkable. “Reflexes like the tonic neck reflex — in which your baby turns his head to one side, straightens one arm, and holds the other out — are critical to labor and delivery, helping your baby squirm around during the birth process, stimulating the uterus to keep contracting,” says Dr. Brazelton. In essence, he’s helping your labor progress.

Other reflexes are less subtle to a new parent. If left on his mother’s abdomen in a dim, quiet room after birth, a healthy newborn “will rest for about 30 minutes and will gaze at his mother’s face on and off,” reports Marshall Klaus, MD, who wrote the first textbook on neonatology and has coauthored a number of popular books for new parents, including Your Amazing Newborn (Perseus). Then he’ll begin smacking his lips and moving toward the breast completely unaided, using a powerful stepping reflex and bobbing his head up and down to gather momentum. Once at the breast, a newborn will open his mouth wide and place his lips on the areola, latching on all by himself for his first feeding. From that point on, these inborn responses will affect your newborn’s every move. The rooting reflex, for example, helps your baby seek nourishment. However, seemingly random, reflexive movements may be more intentional than we first thought. “When in a quiet, alert state, and in communication with a caregiver, some babies will reach out to try and touch something,” says Dr. Klaus.

Normal newborns at birth apparently have the underlying potential to reach for things, he explains, but their strong neck muscles are linked to their arms, so that a slight neck movement moves the arms as well. This connection protects the baby’s head from suddenly dropping forward or backward.

Baby’s Thinking

It depends upon how you define thought; of course, a newborn can’t share ideas. But some researchers believe that babies do put concepts together (albeit on a primitive level), evidenced by the fact that they remember and recognize their mother’s voice from birth, and express and respond to emotions before and immediately after birth. One could argue that memory and emotion are inextricably linked to thought. “A baby’s brain grows very differently depending on what sorts of experiences the baby has both in utero and after birth,” says Wendy Anne McCarty, PhD, the founding chair and faculty of the Prenatal and Perinatal Psychology Program at the Santa Barbara Graduate Institute, in California. “During gestation, birth, and early infant stages, we learn intensely and are exquisitely sensitive to our environment and relationships. From the beginning of life, we’re building memories.” Other experts say that a baby’s brain is too undeveloped to do more than orchestrate vital body functions. One fact remains clear: Newborns learn every day and apply that knowledge to their growing repertoire of skills. So can a newborn really think? Watch your baby, and judge for yourself!

Yopu may find the following:-In the first three months, your baby will learn to raise his or her head, smile, kick, move both arms and legs, roll over and make babbling noises. You will also learn to distinguish your baby’s cries, which will help you determine what your baby wants from you. Baby may also learn to wake up less as his or her stomach grows bigger and takes more in at a feeding.

Dr. Klaus discovered that newborns instinctively reach out until about 3 weeks of age, when this ability apparently disappears until about 3 months of age. This coincides with the time it takes your baby to start learning how to integrate his senses and gain control over his muscles. This is a prime example of how your baby’s need to learn so much, so quickly, means he must set aside some tasks while focusing on other, more important ones, such as regulating his sleep-wake cycles and figuring out how to focus his brand-new eyes on all the new sights around him.

So why do all these useful survival instincts seem to disappear so early — some as early as the 2-month mark? A baby spends the first few months of his life reacting to the world around him. But once he starts to understand where he ends and the world begins, which is partly a matter of brainpower, and partly a matter of practice, some behaviors that were once reflexive become active, as gradually baby learns that he can make things happen on his own and affect his environment. And, says Dr. Brazelton, “Just watching a baby learn is enough to give you hope for the human race.”

Baby’s Senses and Sensibility:-
Touch:
Your newborn’s skin is his largest and most highly developed sensory organ. At birth, your baby can respond to variations in temperature, texture, pressure, and pain. Your newborn’s lips and hands have the largest number of touch receptors, which may account for why newborns enjoy sucking on their fingers.

Smell:
By the 28th week of pregnancy, your baby can use her nose. One piece of evidence: Newborns placed between a breast pad from their mother and one from another woman most often turn toward the one with the alluring Mom-smell.

Taste:
In your womb, your baby gets a sampling of flavors as he swallows amniotic fluid. Studies have shown that fetal swallowing increases with sweet tastes and decreases with bitter or sour tastes.

Hearing:
Although your baby’s middle ear is still somewhat immature at birth, as are the sound processing centers of his brain, your newborn can hear you and will prefer human speech over any other sounds, especially if the voice is yours.

Vision:
By the time you actually meet your baby, her eyes are capable of excellent vision; however, her brain is still too immature to distinguish between different shades of color. By the time your baby is 3 months old, she will want to look at the world around her. She’ll prefer bright colors or sharp contrasts, and her favorite thing to look at will be faces.

Resources:

http://www.parents.com/baby/care/newborn/your-baby-from-birth-to-3-months/?page=5
http://www.thebabydepartment.com/babycare/baby-development.aspx

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The unconquered enemy

We humans think of ourselves as intelligent and rational. We have successfully evolved, subdued the lower animal species and conquered the world. We could not be more wrong.

The simple, single-celled bacterium has been around longer than we have, and has effectively survived the ice age, floods, drought and the chemical onslaught of antibiotics.

The medical community thought that it had finally conquered bacteria and infectious diseases after Alexander Fleming discovered penicillin in 1928. Doctors couldn’t have been more naive.

Bacteria have offensive, defensive, stealth fighter and commando manoeuvres that no human army can match. They hide in areas like pus, thick layers of skin, bone and cartilage that antibiotics can’t penetrate. They adapt and change faster than a speeding bullet. They are not bound by narrow-minded considerations like race or ethnicity; they join forces enthusiastically with bacteria of other species. When all else fails they copulate, and during the process, exchange genetic material that provides resistance to antibiotics.

Immunisation is a powerful weapon that boosts the body’s own defence mechanism

Unfortunately, human beings are collaborating in this warfare, unwittingly aiding bacterial victory. Fifty per cent of the total antibiotic production is used for animals. Farmers rearing cows, sheep, goats, chicken and fish often use animal feed fortified with antibiotics to keep their livestock healthy. Sometimes the antibiotics are administered as regular supplements. These antibiotics contaminate the environment. The sub-optimal quantities administered to the animals aren’t enough to kill all the targeted bacteria. Genetic mutations occur and resistant bacteria emerge. These eventually find their way into the human community. Treatment with the antibiotic recommended for that particular infection will then fail, requiring more potent and expensive drugs.

Sometimes doctors may be at fault. They may fail to calculate the correct dosage, particularly in case of children where it is based on the body weight. Sometimes the dosage intervals may be incorrect and the next dose is administered later than required, after the drug has been totally eliminated from the body. Also, in the absence of investigations, the chosen antibiotic may be inappropriate for that particular infection. Instructions to patients may be incomplete, without specifications on whether it is to be taken before or after food, as food may help or impede absorption.

Surgery or ICU admissions raise the spectre of post operative infection, although this should not be the case if proper sterilisation techniques are followed. To prevent this, antibiotics are administered prophylactically prior to, during and after surgery. This aids the development of resistance, as the targeted organism may not be the same as the infecting one.

Often patients, too, have unrealistic expectations. They are not willing to accept the fact that antibiotics do not work against viral infections. They find it difficult to follow a “wait and watch” policy. They fail to realise that it is antipyretics (like paracetemol) and not ad hoc doses of antibiotics that reduce fever. They tend to “doctor shop” till they find someone who will prescribe the antibiotics they want.

Diseases that compromise host immunity allow bacteria to gain a foothold and thrive. In such a scenario, higher and longer doses of antibiotics have to be used. Some of these diseases, like diabetes, can be controlled with a little effort, diet control and exercise.

Our drug control policy is somewhat lax. Pharmacies freely dispense unprescribed schedule H antibiotics in irrational combinations OTC (over the counter). Although this is illegal, their activities cannot be faulted, as “supply meets demand.”

As educated responsible citizens, we should not self medicate and perpetuate this menace. Immunisation is a powerful weapon that boosts the body’s own defence mechanisms. As soon as the invading bacteria launch an attack, the sentries and foot soldiers (white blood cells and immunoglobulins) sound the alarm, engulf and annihilate the bacteria. Immunisation is available against diphtheria, tetanus, pertussis (whooping cough), H. influenzae (meningitis, ear infections, bronchitis), Pneumococcus (pneumonia, ear infections, meningitis), Meningococcus (meningitis) and typhoid.

Researchers are trying to discover newer and stronger antibiotics to combat the menace of bacterial resistance. They cost crores to discover and test before they can be finally used. We therefore need to conserve and use what we already have. Once the rate of discovery ceases to keep pace with the mutation in the bacteria, we have lost the battle to the microbes.

So, I strongly believe that people should rely more on alternative therapy like yoga,meditation,herbal medications etc. for maintaining a good health unless there is any medical emergency .

Source:The Telegraph(Kolkata,India)

A ray of hope for autism.

After years of research, scientists have zeroed in on the genes responsible for autism. V. Kumara Swamy reports

A five-year-long international study that looked into the genetic underpinnings of autism has zeroed in on new genes, giving hope to millions that some day a treatment for this complex brain disorder may be possible. According to current estimates, around 1.7 million people suffer from autism in India.

 

The preliminary results of the study, gleaned from a large sample of 1,200 families with multiple cases of autism in 19 different countries, were published in this month’s issue of Nature Genetics. More than 120 scientists from 50 institutes participated in the exercise.

The Autism Genome Project, launched way back in 2002, in its first phase assembled the largest gene “biobank” in the world. It conducted a comprehensive genome scan, announcing last month that the susceptible genes  responsible for inheriting the risk of the disease  have been identified.

Autism is a psychiatric disorder that inhibits a child’s ability to communicate and develop social relationships, resulting in slow learning and severe intellectual impairment in some cases.

The identification of the susceptible genes, say the experts, will provide an insight into the basis of the disease as well as pave the way for developing intervention methods.

The scientists had at their disposal a gene chip  technology that can rapidly look for genetic commonality in the samples collected.

The new study implicates a previously unidentified region of chromosome 11 and neurexin 1, a member of a family of genes believed to be important in neuronal contact with and communication to other parts of the body. Although there have been several genetic analyses for autism, the results have not been uniform and none has been performed on such a large scale before.

Researchers also speculate that there may be five or six major genes and as many as 30 others involved in autism. If a foetus has more of these genes, there is a higher chance of being born with autism or a more severe form of the disease.

According to Andy Shih of Autism Speaks, a New York-based organisation, the findings could have an impact in the near future. Some of the data will have immediate diagnostic impact, and the new understanding of the genetic contributors will give direction to the development of targeted treatment and intervention,  he says. Shih’s organisation is one of the funders of the current research study.

First classified as a specific disorder over 50 years ago, the incidence of autism is rising steadily, although the criteria for diagnosis have changed over time.

There have been various estimates for autism in India, but no prevalent study that can arrive at a definite figure, says Dr Shobha Srinath of the National Institute of Mental Health and Neuro Sciences (Nimhans), Bangalore. Moreover, there may be underreporting in many places owing to ignorance, she adds.

While it is estimated that one in every 500 children suffer from autism in India, in countries like the US, the problem is more acute with the figure being one in every 150 children. According to experts, the disease affects more boys than girls. In the UK, autism is said to affect one in every 100 children.

Researchers have for long suspected a genetic link to the disease, and the latest study only confirms that, says Dr J.R. Ram, consultant psychiatrist, Apollo Gleneagles Hospital, Calcutta. “The study is a breakthrough so far as understanding the problem is concerned, but because autism is such a complex disease we need to be realistic about the findings,” he adds.

Parents, it seems, are also of the same opinion.  see this study as a ray of hope, but I think we are still some distance away from any effective treatment in the form of medication,” says Indrani Basu, the parent of an autistic child and also the head of the Autism Society of West Bengal, Calcutta.
Source:The Telegraph (Kolkata,India)

Why boys are brats

The first Indian genetic study on a common behavioural disorder explores why inattentiveness and hyperactivity are more common in boys than in girls. G.S. Mudur reports .

Mothers who carry a ‘faulty’ version of the MAOA gene prefentially hand it down to their sons.

The exact biological basis for boys appearing naughtier than girls has long eluded scientists, but Calcutta-based geneticist Kanchan Mukhopadhyay has stumbled upon something that may at least partly explain why more boys than girls get into trouble in school and at home.

Mukhopadhyay has been looking for genes that might help unravel the complexity of attention deficit hyperactivity disorder (ADHD) — a behavioural disorder so common that psychiatrists expect two children in every class of 40 to have it. It’s a condition marked by inattentiveness, impulsive action and hyperactivity, and surfaces typically during early school years. Most children diagnosed with ADHD while in school continue to have the symptoms in adolescence and adulthood.

Now, in a study of a medium-sized gene on the human chromosome X — one of the two sex chromosomes — Mukhopadhyay and her colleagues have detected a possible mechanism that might explain why ADHD is four times more common in boys than in girls. The researchers at the Manovikas Biomedical Research and Diagnostic Centre, Calcutta, have discovered that mothers who carry a “faulty” version of the gene preferentially hand it down to their sons.

“This is an effort to understand better the biochemical changes in the brain that accompany ADHD,” said Swagata Sinha, a psychiatrist and a member of the research team. “When we treat patients with ADHD today — whether through behaviour therapy or medication — we find that some respond well, while others do not respond. A clearer picture of what’s going on inside the ADHD brain may help us improve therapy.”

In their study, the Manovikas Centre researchers analysed the genetic alphabets on a gene that makes an enzyme called monoamine oxidase (MAOA) in a group of 64 boys and nine girls with ADHD who were brought to their clinic as outpatients. They also examined the corresponding genes in both the parents of 67 children.

“We picked the MAOA gene because it has long been viewed as a candidate gene implicated in ADHD,” Mukhopadhyay told KnowHow.

Nearly a decade ago, researchers in the US had shown that mice that lack MAOA show aggressive behaviour. Several other studies have also pointed to a role for MAOA in human behaviour and brain physiology, perhaps through its action of altering the levels of various brain chemicals that neurons use to signal each other.

The study by the Manovikas Centre researchers has shown that one version of the gene that causes the MAOA enzyme to have lower-than-normal activity is associated with ADHD. Patients with ADHD are more likely to have this version of the gene than people without ADHD. Their findings were published in a recent issue of the American Journal of Medical Genetics: Neuropsychiatric Genetics.

The researchers caution that their findings need to be validated through larger samples of patients and that the presence of the variant of the gene that makes only low activity enzyme can at best only predispose people to ADHD. “Several genes are likely to be involved in ADHD — one gene alone cannot explain it,” said Mukhopadhyay.

Previous studies have suggested that environmental triggers may act on people who are already genetically predisposed to ADHD. And while ADHD had long been viewed as a problem emerging from a chemical imbalance in the brain, an imaging study three years ago revealed that there may also be subtle anatomical differences in areas of the brain that control behaviour changes observed in ADHD. In that study, US researchers had used a new brain mapping study to detect what they described as abnormal brain anatomy in a small set of children with ADHD.

The researchers at the North Shore Long Island Jewish Health System in New York found abnormalities in the circuitry in several regions of the brain such as frontal cortex, basal ganglia and the cerebellum.

“These areas are involved in the processes that regulate attention, impulsive behaviour and hyperactivity — the key symptoms of children with ADHD,” said Manzar Ashtari, associate professor of psychiatry and radiology at the clinic.

The evidence for the role of environmental triggers was bolstered by another study in the US last year which showed that genetic variations may determine how children respond to potential toxins in the environment. The study by researchers at the Cincinnati Children’s Hospital suggested that genes can predispose a child to negative effects of environmental exposure to lead.

The study found that only children with certain variations of a gene that helps control the levels of a brain chemical called dopamine appear specially vulnerable to the adverse effects of lead on attentiveness.

Increasing lead exposure tended to impair performance in boys more than in girls. Boys appear more vulnerable than girls. “This is consistent with the fact that boys have higher rates of ADHD than girls,” said Tanya Froehlich at the Cincinnati Children’s Hospital.

The Calcutta study has also revealed a possible additional mechanism to explain why boys have more ADHD than girls. The study has indicated that the version of the MAOA gene associated with low-activity enzyme is “preferentially transmitted” from mothers to boys with ADHD.

“It is still unclear why this variant of the gene is preferentially transmitted to boys,” Mukhopadhyay said. However, the researchers also point out that their study included only nine girls, and a larger study would be needed to ascertain that such transmission does not occur in girls.

The MAOA gene lies on the X chromosome which both boys and girls get from their mothers. In principle, this alone could explain why ADHD is less common in girls than in boys. The sex chromosome is XX in girls and XY in boys.

“Boys have only one copy of the X chromosome. If they get the low-activity version, they have nothing else to compensate for its low activity. But girls have two X chromosomes. In the event that one X has the low-activity enzyme, the other can compensate by producing normal levels,” said Mukhopadhyay.

Source:The Telegraph (Kolkata,India)