Life to the Full
29/May/2007
From the Sydney Morning Herald
For cystic fibrosis sufferers, early diagnosis helps enormously but the condition requires a life of regimented management.
Danni McClellan lives the busy life of many young women her age. At 21, she is in the third year of a university degree. She plays sport and goes out every weekend. Recently she travelled to Norway on exchange for nine weeks.
Behind that hectic schedule, however, is a lot of careful planning and preparation. McClellan suffers from cystic fibrosis (CF), one of the most common life-threatening recessive genetic conditions affecting Australian children. To cope with her hectic schedule she must follow a formidable program of medication and treatment. Through early diagnosis and aggressive management, more sufferers than ever are surviving into adulthood.
"I have a regime that I follow every day," she says. It involves taking antibiotics, a puffer, vitamins, pancreatic enzymes with food and three lots of nebulisation. On top of that she has one to two hours of chest percussion to clear her airways.
"I go out every weekend, but if I am going out I make sure that I do physio and nebuliser before I go out," she says. In Norway, she "had to take a big Esky everywhere because some of my medications have to be refrigerated".
McClellan, however, is one of the more fortunate CF sufferers; she belongs to a new generation who were diagnosed at birth.
Cystic fibrosis is a disorder that affects salt and chloride channels in cells that produce mucus. As a result, CF sufferers produce thick, sticky mucus, which affects the function of many organs in the body, including the lungs, gut, pancreas and, sometimes, liver. In particular, the ability of the lungs to clear the mucus from the airways is compromised, predisposing sufferers to respiratory tract infections and eventually respiratory failure and premature death. There is no cure.
Sufferers must undergo a gruelling daily regime of up to three hours of physiotherapy, including chest percussion, to clear mucus from the lungs. They frequently suffer respiratory-tract infections and are more vulnerable to infection with multi-resistant bacteria, necessitating frequent and often constant doses of antibiotics.
CF causes pancreatic insufficiency, so sufferers must take enzyme supplements with each meal to enable them to digest food properly. Affected children need about 30 to 40 per cent more calories to ensure they maintain a healthy body weight.
CF is an inherited disorder affecting an estimated 3000 Australians. According to Cystic Fibrosis Australia, about one in 25 people of Caucasian ancestry carry the CF gene, most without knowing it. Where both parents are carriers, there is a one in four chance that their offspring will be born with CF, and a 50 per cent chance that children will be silent carriers of the gene. Some children with CF are more severely affected than others, probably because of individual variations in the CF gene.
According to Terry Stewart, chief executive of Cystic Fibrosis Australia, the organisation responsible for running the Australian Cystic Fibrosis Data Registry, the average lifespan of CF sufferers is about 36 years. But that is gradually increasing.
"When the registry started in 1998, 27 per cent of CF sufferers were over the age of 18," Stewart says. "In the latest report [2004], that has increased to 42 per cent of the population."
Dr Peter Cooper is a respiratory physician and director of the cystic fibrosis unit at the Children's Hospital at Westmead. He credits the improvement in part to the fact that all babies in Australia are screened for CF at birth.
Early diagnosis facilitates early, aggressive treatment. "We start physiotherapy at birth," Cooper says. "We give them enzymes to help absorb their food with every meal and we start them on antibiotics in the first year." Central to successfully managing CF in young patients is educating parents. "The success of treatment depends much more on parents than with any other disease," Cooper says. The impact on families is enormous, with daily management of affected children taking up to six hours. "At our clinic we've seen families where five out of six children have CF," Cooper says.
"If parents are taught how to look after their children and educated about recognising early warnings and put in touch with a support system, then we can prevent a lot of damage.
"Basically there hasn't been a huge change in the type of care we're giving. What's happening is due to a change in how aggressively we treat and our ability to pick up infection early."
When it comes to access to drugs, our health system is yet to catch up. Many physicians believe that a new drug, dornase alfa (Pulmozyme), which works by breaking down thick mucus, will benefit babies and toddlers. However, access to this expensive drug is limited by strict criteria.
"Generally, it is available to patients who are more severely affected and can show a 10 per cent improvement in lung function," Cooper says. "That limits its use to children over five or six who are able to blow into a lung function machine, but it is not yet available to younger children."
Similarly, use of the powerful antibiotic and anti-inflammatory drug azithromycin is typically restricted to more severe cases. That may change. Australian researchers are collaborating with colleagues in Europe to determine whether drugs such as dornase alfa and azithromycin are effective when used in month-old babies with CF.
"We're trying to understand if these drugs can be used in a preventive sense," Cooper says. If they can, researchers may be able to make a case for broadening access to the drugs.
The longer lung function is preserved and colonisation of the lungs with resistant bacteria is delayed, the longer patients will survive. When respiratory physician Peter Bye started work at Royal Prince Alfred Hospital's cystic fibrosis centre for adults in 1986, there were 30 patients. Now there are 212.
"When I first came, young patients would tell me things like they wanted Elvis played at their funeral, but the expectations of these people are very high now," he says.
But the longer patients survive, the more complex their management becomes. Compared with their pediatric counterparts, adults with CF are five times more likely to have severe lung disease and at least one third harbour multi-resistant organisms. To date, 70 patients from the RPAH's cystic fibrosis centre have undergone lung transplants.
Because transplanted lungs are sourced from CF-free donors, the new lungs do not have and will not develop CF. However, recipients must take potent anti-rejection drugs to protect their new lungs. Moreover, the recipient's pancreas, sweat glands, sinuses and reproductive tract are still affected, necessitating specialist care.
"We see a lot more lung transplants in adults than in children because, having lived longer, their lung function is much worse," Bye says.
Adults with CF are also more likely to suffer from other complications. About 30 per cent have insulin-dependent diabetes due to chronic pancreatic insufficiency. About 10 per cent are affected by osteoporosis, which develops due to poor nutrition. It is estimated that only one-third of adults with CF have normal bone density.
While CF typically renders male sufferers infertile, advances in sperm-harvesting and IVF mean that men with CF can still father children.
"These techniques have a very high success rate," Bye says. "At our clinic we have 15 males who have fathered 21 children between them."
Current research is focused on determining the best way to target multi-resistant bacteria, and whether the presence of certain strains of bacteria may indicate a poorer prognosis.
Bye says the management of adult CF is an increasingly pressing health concern. "At least 40 per cent of people with CF in Western countries are now adults," he says. "It won't be long before there are more adults with CF than children. But the good news is that life continues to improve for all patients with CF because of ongoing medical?advances."
Danni McClellan says that, if anything, she feels healthier than she did when she was younger. "I look after myself, I play a lot of basketball and keep fit," she says.
"Every year I go to hospital for about 10 days for a tune-up. If I maintain the routine I have there's really no reason why I should get much worse.
Sometimes having CF is a massive pain - it's frustrating when you don't feel well - but generally I feel good."
She plans to pursue a career in clinical psychology and start a family. "I know that there are some antibiotics you can't take if you're pregnant or breastfeeding so I may need to change my medications but I definitely want to have kids."
Anne Fawcett
Sydney Morning Herald May 25 2007
Photo: Domino Postiglione
