JOURNAL CLUB

The top ten of 2000

Commentaries By Michael G. Burke, MD

Editor's Note: It's time, once again, to offer our selection of the past year's top pediatric stories. Here are ten articles from Y2K that Dr. Burke believes may be helpful to pediatricians as they care for children. They are not in order of importance.

Do patients know how to use their EpiPens?

Patients prescribed self-injectable epinephrine and their parents often don't know how to use the delivery devices correctly and don't have the medication readily available, according to a study. Pediatricians, too, frequently are not familiar with the EpiPen, EpiPen Jr., and Ana-Kit and may fail to review their use with patients.

Investigators surveyed families of food-allergic children with a mean age of 6.4 years, who were prescribed self-injectable epinephrine by a pediatrician or an allergist. Although 86% of the families said they had the device with them "at all times," only 71% had the epinephrine at the study visit. And since 10% of that group had devices beyond the labeled expiration date, only 55% of the 101 families had unexpired epinephrine on hand when the survey was conducted. Of children attending school, 77% had the medication available in their school, but only 81% of this group had ensured that the school knew how and when to give the medication.

In addition to administering the questionnaire, investigators asked participants to demonstrate correct use of the devices with which they were familiar, using a trainer. Only 32% could do so, though 49% of parents recalled that a physician demonstrated use of the device and 80% said they received a verbal explanation. Of the 29 pediatricians enrolled in the study, 18% were familiar with at least one device and were able to demonstrate its use; 24% gave patients written material about use indications (Sicherer SH et al: Pediatrics 2000;105:359).

Commentary: We attending physicians had a pretty weak performance here: 21% were able to demonstrate use of an EpiPen. For a quick refresher, contact the Food Allergy Network at 800-929-4040 or on the Web at www.foodallergy.org . For $2 plus shipping and handling, this group sells a practice EpiPen (trainer) without needle or medication.

A single steroid injection for asthma attacks?

A single intramuscular (IM) injection of dexamethasone acetate appears to be as effective as a five-day course of oral prednisone for treating young children with mild to moderate exacerbations of asthma. Investigators, seeking an alternative to oral prednisone, which many young children balk at taking, compared the two treatments in 32 children who required corticosteroids to treat asthma exacerbations. The children, who were outpatients at a tertiary care medical center, ranged in age from 6 months to 7 years. They received either a single dose of IM dexamethasone acetate (~1.7 mg/kg) or oral prednisone (~2 mg/kg/d) for five days. Parents kept an asthma symptom diary, used to measure changes in asthma signs or symptoms (clinical asthma score), from days 1 through 5 of treatment.

Clinical asthma scores improved significantly in both groups during the first five days of therapy, with no notable difference between the two groups. Three children refused more than three quarters of their oral prednisone doses, and another four missed from one third to half the doses despite their parents' best efforts. The IM injection caused no complications, and about 70% of parents in both groups said they would choose it to treat their child's next asthma attack (Gries DM et al: J Pediatr 2000;136:298).

Commentary: The IM injection may be an alternative for outpatient asthmatics who refuse foul-tasting oral steroids. The authors are careful to point out that the IM preparation used was dexamethasone acetate, not the shorter-acting dexamethasone phosphate commonly used for treating croup. They also clearly state that these findings should not be extrapolated to children with severe asthma exacerbations that require hospitalization. That's a different study, which needs to be done.

Meningococcal carriage surges at start of college

A study from the United Kingdom shows that during the beginning of the college term meningococci spread rapidly in first-year students. Investigators based their findings on a study of 2,507 college freshman who completed a questionnaire about personal characteristics and lifestyle and submitted to a pharyngeal swab on one of the first four days of the semester. Second swabs were taken either one month or two months later.

Although the initial carriage rate for Neisseria meningitidis was low (8%), it rapidly increased to 23% during the first week of school. The average carriage rate of meningococci during the first week among students living in dormitories that provided meals was 14%. One month later it was 31% and in two months it had reached 34%. The carriage rate was lower in dormitories where students ate elsewhere. Although non-C strains, mainly serogroup B and nongroupable meningococci, predominated in the swabs taken the first week of school, serogroup C meningococci was the most common strain acquired during the term. Analysis showed that active and passive smoking and kissing were risk factors for carriage; in addition, students who lived off campus were less likely to be carriers than those who lived on campus. Risk factors for acquisition of meningococci were male gender, active smoking, visits to campus bars and nightclubs, kissing, and living in coed dorms. Since this study was conducted, the United Kingdom introduced meningococcal vaccination for university students (Neal KR et al: BMJ 2000;320:846).

Commentary: In the past year, how often have parents of college students asked you if they should have their child immunized against N meningitidis? The Advisory Committee on Immunization Practices has recommended that families of freshmen living in dorms be given the option of immunizing their children. For details, go to the Web site of the Centers for Disease Control and Prevention, www.cdc.gov , and search on meningococcus.

Reading to toddlers boosts vocabulary

A simple and inexpensive intervention, delivered as part of well-child care, increases how much parents read to children and enhances the language development of toddlers, according to new research conducted in a multicultural group of 205 low-income families with infants. The infants were between 5 and 11 months old when the study began, with results of the intervention evaluated about a year later. Participating families were told the study was about children's play activities, interests, language development, and sleep habits and were interviewed about these subjects when the study began. At well-child visits, pediatricians gave half the families an age-appropriate children's board book; an age-specific handout explaining how children can benefit from, enjoy, and interact with books; and literacy-promoting anticipatory guidance. The other families received no books or materials related to literacy.

After an average of 3.4 well-child visits, repeat interviews with parents and tests of the children's vocabulary showed that the intervention group had higher vocabulary scores than the control families. This result applied to toddlers 18 to 25 months old, not to those who were younger. In addition, in intervention families there was a 40% increase in parents who said they and their child usually read together at bedtime, reading aloud was one of their child's favorite activities, or that it was one of their own favorite joint activities. The comparable increase in these preferences in control families was 16%. Analyses that controlled for demographic variables showed that the effects of the intervention were strongly associated with increased emphasis on shared reading experiences and their enjoyment (High PC et al: Pediatrics 2000;105:927).

Commentary: Here's some solid evidence to support advocates of Reach Out and Read and other office-based literacy programs. It's nice to see that these simple programs, which seem to make sense, really work.

Antibiotics and risk of HUS after E coli infection

Use of antibiotics in children with gastrointestinal infections caused by Escherichia coli O157:H7 increases the risk of hemolytic-uremic syndrome (HUS), a new report shows. Investigators conducted a prospective study of children younger than 10 years who had diarrhea caused by E coli O157:H7. Ten (14%) of the total group of 71 developed HUS. Of these 10 children, five had taken antibiotics, though only nine (13%) of the 71 had been given antibiotics, at the direction of their physician. Investigators studied possible confounding factors for the association between antibiotics and development of HUS: demographics, the presence or absence of specific symptoms, the length of time from the onset of diarrhea to when the initial stool culture was obtained (a shorter interval may reflect more severe extraintestinal injury prompting earlier evaluation and greater risk for the syndrome), and initial measures of illness severity. After adjustment for the most important of these factors, antibiotic administration remained a risk factor for development of HUS (Wong CS et al: N Engl J Med 2000;42[26]:1930).

Commentary: Children treated with antibiotics were more than 14 times more likely to develop HUS than the other children. The authors suggest that empiric antibiotic use be avoided in children with diarrhea. If you are leaning toward treating, hold off until stool cultures identify a pathogen other than E coli O157:H7.

Getting blood cultures—fast

A continuously monitoring blood culture system detects most significant positive cultures within 48 hours and almost all positive cultures by 72 hours, according to a prospective study. During the 47-month study period, investigators obtained 10,200 single-bottle blood cultures taken in the emergency department and outpatient clinics of an urban pediatric hospital. Patients ranged in age from less than 1 week to 24 years. Of 711 cultures that became positive, 258 (36.3%) contained only pathogens, 370 (52.0%) contained only skin contaminants, and 83 (11.7%) contained a mixture of contaminant and pathogen. Of the 258 cultures containing only pathogens, 14% were positive by 12 hours of incubation, 87% by 24 hours, 92% by 36 hours, 95% by 48 hours, 98% by 60 hours, and 99.7% by 72 hours. A total of 239 cultures yielded pathogens critical to pediatrics: Streptococcus pneumoniae, Salmonella and other Enterobacteriaceae, Neisseria meningitidis, and Groups A and B streptococci. Within 24 hours, 226 of these cultures (94.6%) had become positive. By 48 hours, 98.3% had become positive, and four remained undetected. Blood cultures containing only contaminants became positive more slowly than cultures that contained pathogens (McGowan KL et al: Pediatrics 2000;106:251).

Commentary: For cultures positive for S pneumoniae, the mean time to positive culture was only 14.04 hours with a 95% confidence interval of 13.61 to 14.48 hours. This study may be useful to you if your practice is to treat fever without a source in children younger than 3 years with empiric ceftriaxone. Deciding what to do at the 24-hour follow-up may be easier if you know that most positive cultures will be positive by then.

Gun storage practices: Whom do you ask?

Women living in homes where guns are stored may be unaware that these firearms are not stored safely, according to new research. Using a national, random, digit-dial telephone survey, investigators analyzed responses from 434 households with children younger than 18 years in which an adult (generally a man) either personally owned a gun or lived in a gun-owning household but did not personally own a gun (generally a woman). Whereas 21% of gun owners said that a household gun was stored loaded, only 7% of nonowners made a similar report. Likewise, 9% and 2%, respectively, indicated that a household gun was stored loaded and unlocked. These findings, investigators said, suggest that nongun owners in homes with guns, 87% of whom are women, may be unaware that guns in their homes are stored in a way that experts agree is unsafe (Azrael D et al: Pediatrics 2000;1063:e31).

Commentary: What is the moral of this story? When you ask for history with regard to storage of guns in the home, consider the source of the information. Target your anticipatory guidance to your audience. Encourage nonowners living in homes with guns to find out how those guns are stored. If the gun owner is in the office, tell him directly the advantages of locking and unloading his firearms.

Turner syndrome diagnosis often delayed

A study of 81 girls with Turner syndrome (TS) shows that this condition often is not diagnosed until late childhood or adolescence despite growth failure and the presence of numerous typical historical and physical characteristics of TS. The mean age at diagnosis for the 81 patients was 4.2 years and ranged from prenatal life to 16.8 years. Lymphedema or webbed neck was present in all patients diagnosed at birth. Six of 38 patients (16%) who had a history of lymphedema at birth did not get a diagnosis in infancy, however. Of patients who received a diagnosis in childhood or adolescence, 25 of 39 (64%) had lymphedema at birth or two or more of the dysmorphic features, such as webbed neck, nail dysplasia, high palate, and short fourth metacarpal, that might have led to the diagnosis of TS at birth. These patients did not receive a diagnosis until an average of 9.1 years later.

After infancy, short stature was the feature that most often led to an evaluation by karyotype. The interval between decline in height below the fifth percentile and diagnosis was long, however, a mean of 5.2 years. Patients exhibited multiple clinical features as well as short stature that might have served as diagnostic clues for TS. They had medical problems such as delayed puberty, nonverbal learning disabilities, feeding difficulties during infancy, coarctation of the aorta, or strabismus, in addition to the common dysmorphic features listed above. Investigators estimated that overall delay in diagnosis of TS for patients whose condition was recognized in childhood or adolescence was 7.7 years (Sävendahl L et al: J Pediatr 2000;137:455).

Commentary: To avoid delay in diagnosis of Turner syndrome, the authors offer these guidelines for screening. Consider a karyotype in all girls with unexplained short stature (< fifth percentile), webbed neck, peripheral lymphedema, coarctation of the aorta, or delayed puberty (absence of Tanner 2 breast development at 12.5 years). Also consider screening in girls with two or more of these features: nail dysplasia, high arched palate, short fourth metacarpal, and strabismus.

Zanamivir prevents family spread of influenza

Prophylaxis with zanamivir is an effective option for preventing the transmission of influenza within households, according to a new study. Investigators divided 337 families that had one member with an influenza type illness into two treatment groups. Family members with index cases of influenza received either inhaled zanamivir (10 mg) or placebo twice a day for five days. The other healthy family members received the same study drug as the ill member in their household, either zanamivir (10 mg) or placebo once daily for 10 days.

Among families in which the index illness was laboratory-confirmed influenza, the percentage in which influenza developed in contacts was 29% in the placebo group and 8% in the zanamivir group. Among families in which the index illness proved not to be influenza, the percentage was 8% and 1%, respectively. The rate of zanamivir protection against influenza in healthy household contacts was 79% overall, 72% in the families with confirmed influenza, and 87% in the group with influenza-negative index cases. Zanamivir prophylaxis was effective against both influenza A and influenza B, did not appear to be related to development of zanamivir-resistant influenza variants, and was well tolerated. In addition, among the subjects with index cases of laboratory-confirmed influenza, the median duration of symptoms was 2.5 days shorter in the zanamivir group than in the placebo group (Hayden FG et al: N Engl J Med 2000;343:1282).

Commentary: This may be big news for families in flu season and also for residents of long-term care facilities and other groups of high-risk people.

A marker for hypertrophic pyloric stenosis

Hypoplasia or absence of the mandibular frenulum is commonly associated with infantile hypertrophic pyloric stenosis, a new study finds. The mandibular frenulum is a normal midline craniofacial structure extending from the vestibular mucosa of the lower lip to the gingival mucosa of the lower jaw. Investigators compared clinical data for 25 infants with surgically confirmed infantile hypertrophic pyloric stenosis and 319 controls with matching gestational ages. Of the 25 subjects, 23 (92%) had a hypoplastic or absent mandibular frenulum, compared with five (1.6%) of the controls (De Felice C et al: J Pediatr 2000; 136:408).

DR. BURKE, Section Editor for Journal Club, is Chairman of the Department of Pediatrics at Saint Agnes Hospital, Baltimore. He is a Contributing Editor for Contemporary Pediatrics.

CLINICAL TIP

What an inspiration!

If you are frustrated by toddlers who refuse to take deep breaths, try this maneuver. First have the child sit on the parent's lap with his back to the pediatrician. Then place the stethoscope on his chest under his T-shirt. With your other hand, lightly press on the abdomen, then slowly move your hand upward toward the diaphragm. Hold your hand in that position for one breath, which will be shallow because diaphragmatic excursion is limited. Then release your hand while continuing to listen to the chest, and you will find that the child's next breath will be a deep inspiration.

Robert Giusti, MD
Brooklyn, N.Y.

Do you have a Clinical Tip to share with colleagues? Let us know; we'll pay $50 for each item accepted for publication. Tips sent by mail should be addressed to Molly Frederick, Clinical Tips Editor, Contemporary Pediatrics, 5 Paragon Drive, Montvale, NJ 07645-1742. If you submit by e-mail (Molly.Frederick@medec.com), please include your mailing address.

 

Michael Burke. The top ten of 2000. Contemporary Pediatrics 2001;0:134.