Vol. 16 •Issue 14 • Page 8
Pediatric Reactive Airway Disease:
A Link to RSV Points To Possible Treatment
While the birth of a new baby is a time of elation, many new parents, despite their Herculean nesting efforts, find themselves unprepared. Certainly, Mom and Dad have a crib, diapers and other baby accessories in place. However ready the home might be, there are still those times of uncertainty ahead—like when their newborn falls sick to an illnesses like Respiratory Syncytial Virus (RSV) bronchiolitis.
As RTs know from prior work loads, RSV is hard on kids at certain times of the year, especially during the winter months when RSV cases skyrocket. Bronchiolitis, one result of RSV, is a viral infection of the lower respiratory tract, occurring most often in children younger than one year. Characteristics include respiratory distress, wheezing in the expiratory phase of breathing, low-grade fever, cough and nasal discharge.
RSV, the most common cause of pneumonia in infants, affects nearly every youngster to some degree by the time they reach age two. Currently there is no evidence-based therapy to combat it. Still, the threat from RSV is becoming increasing more severe.
“The hospitalization rate for bronchiolitis in infants has more than doubled in recent decades and now constitutes one in six of all hospitalizations in infancy,” noted Hans Bisgaard, MD, professor of pediatrics at Copenhagen University Hospital in Denmark and a member of a group studying montelukast and Respiratory Syncytial Virus, in a press release. “Nearly 50 percent of all infants hospitalized with lower respiratory disease were associated with RSV bronchiolitis. In addition, RSV represents a major burden for outpatient visits for RSV airway infections presenting as upper airway respiratory tract infections and exacerbations of bronchitis and asthma.”
But what often happens next can be equally difficult to treat. Severe cases of RSV bronchiolitis are commonly followed by reactive airway disease (RAD), with recurrent wheeze and other asthma-like symptoms. Bisgaard et al. theorize this link could account for some of the increase in incidence in early childhood wheeze. Like RSV, no current therapies are supported by evidence.
Bisgaard’s group recently studied whether a current asthma drug might help control RAD in children. They investigated 116 infants who had symptoms of moderate to severe RSV bronchiolitis that required hospital admission. Each of the subjects, who were between three months and three years of age, became ill during two winter seasons from December 1999 to March 2001. They published the results of their findings in the February issue of the American Journal of Respiratory and Critical Care Medicine.
Of the 116 infants studied, 55 of the children received placebo treatment and the others were treated with 5-mg tablets of montelukast (Singulair) from Merck. Treatments were given each night for 28 days, and symptoms were recorded on a diary card.
According to the investigators, the infants on montelukast were free of any symptoms during 22 percent of their days and nights, compared with 4 percent symptom-free days and nights for those on placebo. Additionally the children experienced a reduction in daytime cough and a significant delay in exacerbations. No children showed any significant side effects.
The researchers believe the treatment affects the reactive airway disease secondary to the bronchiolitis rather than the acute inflammation changes associated with the bronchiolitis.
The authors said specific receptor antagonists had recently become available against cysteinyl-leukotrienes (Cys-LT), which are released during RSV airway infection in infants. Cys-LTs are known to cause bronchial obstruction and other problems. Chewable montelukast 5 mg tablets were the specific receptor antagonists researchers used for treatment against the reactive airway disease.
“The implications of these findings may not be restricted to RSV bronchiolitis but may reflect a general effect on postviral hyperresponsiveness airway symptoms,” said Bisgaard. “Such treatment may have important implications for the treatment of viral-induced exacerbations of asthma and perhaps other chronic obstructive airway disease in children and adults.”
Currently, montelukast is approved for use in asthmatic children as young as age five. Asthma inflects roughly 5 million children in the U.S. and approximately 1.3 children under the age of five.
As far as preventing RSV with a drug, thus effectively halting the infection before it begins, the jury is still out. One study published last year tested the cost effectiveness of Synagis, a sometimes-successful preventive measure against RSV. In this case, a pound of prevention may be too much.
“We found that it is more expensive to treat these children with Synagis in an attempt to prevent RSV hospitalization than it is to pay for the medical costs actually associated with hospitalization,” said Nahed El-Hassan, MD, a neonatology fellow at Strong Children’s Hospital in Rochester, N.Y. “For illustrative purposes, let’s assume one clinic spends $47,000 to provide Synagis to 20 children for one RSV season. These efforts prevent an average of only one hospitalization, which costs less than $7,000. We knew treating these children was expensive and sometimes inefficient, but this was eye-opening.”
Synagis treatment involves giving children monthly injections of the medicine during RSV season, which typically lasts from November through March. The study’s authors estimate it costs between $2,000 and $8,400 to provide the treatment to one patient during a single RSV season.
“Synagis does not reduce mortality, which fortunately is very low,” said co-author Timothy Stevens, MD. “The effects of the drug wear off in 30 to 60 days, and the baby is susceptible to the virus again the next RSV season. A vaccine that can provide long-term protection is needed.”
“Certainly, Synagis provides some children with a great benefit,” according to El-Hassan. “What we need to do now is determine ways to target the treatment so that those children who are most at risk are the ones receiving it. If we can identify those children and provide the drug to them, we’ll make a big difference at a decreased cost.”
You can reach Shawn Proctor at [email protected].
RAD or Asthma: Miscommunication Often Foils Diagnosis
Physicians and other caregivers need not tiptoe around diagnosing a child with asthma, according to a new study from Pediatric Research in Office Settings (PROS), the practice-based research network of the American Academy of Pediatrics.
According to the study authors, diagnosing asthma in young children is a critical first step in disease management. Yet the message is often poorly conveyed.
In the study, researchers reviewed the diagnosis of more than 600 patients with respiratory symptoms in 21 pediatric practices. The patients ranged in age from one to five years. Doctors recorded diagnoses, as well as what they communicated to parents. Parents recorded the diagnoses they heard.
Researchers discovered doctors often used euphemistic terms for asthma, like asthmatic/wheezy bronchitis and reactive airway disease (RAD), which could cause confusion.
“To allay parents’ concerns, health care providers often use terms like RAD and other euphemisms instead of stating the child has asthma. Even when told their child has asthma, parents will commonly remember the doctor saying their child had an infectious sounding illness,” said Lloyd N. Werk, MD, team leader for the study.
In 62 cases, doctors considered asthma or a related diagnosis likely. But they informed parents of just 46 patients of their suspicions. Even then, parents often came away with a differing diagnosis.
For example, only two parents remembered being told their child had RAD when doctors indicated this was their diagnosis in 25 cases. In the 17 cases in which doctors say they told parents their child had asthma, only nine of the parents came away with that diagnosis.
“Are doctors not saying it, or are parents not hearing it? Either way, this study suggests that if a child has asthma, then the doctor should call it asthma,” said Stacia Finch, MA, PROS project manager and lead author. “Parents react the same way to hearing their child has asthma as they do to the other terms often used to diagnose these symptoms.”