Laurie Varlotta

Airway hyperreactivity in children with sickle cell disease.

Progressive restrictive defect with increasing age, obstructive lung disease, and bronchodilator responsiveness have been reported in sickle cell disease (SCD). Because airway hyperreactivity (AHR) can be underestimated when assessed by bronchodilator responsiveness in patients with normal baseline lung function, the aim of this study was to investigate the prevalence of AHR in SCD by cold-air bronchial provocation testing, and to assess whether AHR can be present in symptom-free patients with SCD. Forty patients aged 6 to 19 years (mean, 10.7 years +/- 3.5 SD) performed pulmonary function tests. Eighteen were known to have a history of reactive airway disease (RAD group), and 22 had no known history of RAD (non-RAD group). A control group, aged 6 to 7 years (mean, 10.5 +/- 3.1 years), consisted of 10 siblings of the non-RAD SCD group. There were no significant differences in age and height among the groups. If the forced expiratory volume in 1 second (FEV1) was greater than 70%, cold air challenge (CACh) was performed; if the FEV1 was less than 70%, aerosolized bronchodilator therapy was given. A decrease in FEV1 of more than 10% after CACh or an increase in FEV1 of 12% or greater after bronchodilator inhalation was considered evidence of AHR. In the RAD group, the total lung capacity was 88.9% +/- 14.0% of race-corrected predicted values, the forced vital capacity was 91.2% +/- 12.6%, and FEV1 was 85.3% +/- 16.2%. The mean maximal percent fall in FEV1 after CACh (n = 13) was 18.5% +/- 9.6% and was greater than 10% in 11 of 13 patients. The mean increase in FEV1 after bronchodilator therapy (n = 5) was 11.5% +/- 8.3%, and it was greater than 12% in 4 of 5 patients. In the non-RAD group the baseline total lung capacity was 101.6% +/- 11.7%, forced vital capacity was 95.5% +/- 10.2%, and FEV1 was 93.3% +/- 13.2%. The mean maximal percent fall in FEV1 after CACh (n = 19) was 14.1% +/- 8.8% and was greater than 10% in 13 of 19 patients. The mean increase in FEV1 after bronchodilator therapy (n = 3) was 14.7% +/- 11.3%, and was 12% of greater in 1 of 3 patients. In the control group the baseline total lung capacity was 105.7% +/- 12.1%, forced vital capacity was 96.2% +/- 11.1%, and FEV1 was 92.9% +/- 10.3%. The mean maximal percent fall in FEV1 was 5.0% +/- 2.5%, and was greater than 10% in none of 10 patients. The prevalence of AHR in the control group, the RAD group, and the non-RAD group was zero, 83%, and 64%, respectively (p < 0.0001). The overall prevalence in the SCD group was 73%. We conclude that there is a high prevalence of AHR in children with SCD and that airway hyperreactivity may exist in patients with SCD even in the absence of the clinical symptoms of RAD. AHR may be a significant component of sickle cell lung disease.

Immunogenicity of a new purified fusion protein vaccine to respiratory syncytial virus: A multi-center trial in children with cystic fibrosis

A third generation, purified fusion protein (PFP-3) vaccine was developed to prevent severe respiratory syncytial virus (RSV) disease in high-risk groups. A phase II, multi-center, adjuvant-controlled trial was performed in RSV seropositive children with cystic fibrosis (CF); 151 received the adjuvant-control and 143 received the vaccine. Details of the vaccine-induced immune response are presented. At enrollment, RSV-specific, serum antibodies were comparable between both groups. A highly sensitive and specific serum antibody vaccine profile was established for the PFP-3 vaccine. At post-vaccination and end-of-study, RSV-specific, neutralizing antibody (Nt Ab) and binding antibody (Bd Ab) to the fusion (F) protein were significantly higher in PFP-3 vaccinees. After 28 days post-vaccination, Nt Ab and Bd Ab to F protein titers declined slowly at rates of 0.23 and 0.37 log2 per month, respectively. The PFP-3 vaccine-induced a robust immune response that lasted throughout the RSV season.

Risk factors for emergence of Stenotrophomonas maltophilia in cystic fibrosis.

The number of patients with cystic fibrosis (CF) whose sputum culture has yielded Stenotrophomonas maltophilia has increased in the last 5 years at St. Christophers Hospital for Children. We conducted a case‐control study to determine risk factors for recovery of S. maltophilia in respiratory secretions from patients with CF. We reviewed the outpatient and inpatient records of patients colonized with S. maltophilia between 1993 and 1997, and of age‐matched (at time of initial recovery of S. maltophilia) control patients with CF who had never had a positive sputum culture for S. maltophilia. Variables included age at time of CF diagnosis, gender, severity of CF (based on Shwachman‐Kulczycki (S‐K) scores and spirometry), frequency of hospitalizations, use of oral, intravenous, or inhaled antibiotics, and use of oral or inhaled corticosteroids in the 2 years prior to the first isolation of S. maltophilia from respiratory secretions. Statistical methods included stepwise logistic regression to determine risk factors for acquisition of S. maltophilia.

Barriers to adherence to cystic fibrosis infection control guidelines

In 2003, the American Cystic Fibrosis (CF) Foundation published revised, evidence‐based guidelines for infection control. We sought to assess potential barriers to adherence to these guidelines experienced by health care professionals (HCPs) caring for CF patients.

Vitamin D deficiency is associated with pulmonary dysfunction in cystic fibrosis

BACKGROUND Vitamin D deficiency is common in CF. Whether vitamin D affects pulmonary function in CF is unknown. METHODS Data were abstracted from clinically stable CF patients who had pulmonary function studies and serum 25-hydroxyvitamin D [25(OH)D, ng/ml] levels drawn within 2 months of each other. Findings were adjusted for multiple variables known to affect pulmonary function in CF. RESULTS Enrollees totaled 597. Overall mean 25(OH)D level was 29.6±12.8 ng/ml (SD). Serum 25(OH)D levels showed a significant correlation with forced expiratory volume in 1s (FEV1) % predicted (r=0.20, p<0.0001) and forced vital capacity % predicted (r=0.13, p=0.0019). Multivariate analysis revealed that serum 25(OH)D remained an independent predictor of FEV1 % predicted even after controlling for multiple other factors known to affect CF lung function. CONCLUSIONS Serum 25(OH)D levels are significantly associated with pulmonary function in CF. Further study is required to determine whether this association is causal.

Clinical pharmacist impact on care, length of stay, and cost in pediatric cystic fibrosis (CF) patients

Cystic fibrosis (CF) patients are often treated with aminoglycoside (AG) antibiotics during infective pulmonary exacerbations. Achieving pharmacokinetic and pharmacodynamic (PK/PD) targets to improve outcomes and counteract resistance is paramount.

Monitoring and Internalizing Symptoms Among Youths With Cystic Fibrosis

Youths with cystic fibrosis (CF) may be at increased risk for internalizing symptoms, but factors explaining individual variation in these symptoms are not understood. Monitoring, a cognitive-affective information processing style characterized by the tendency to scan for, attend to, and magnify threatening cues when stressed, was hypothesized to be related to more internalizing symptoms. Optimism, in contrast, was hypothesized to serve as a protective factor and to be related to fewer internalizing symptoms. Eighty-seven youths with CF (ages 7–18 years) attending a clinic visit completed measures of monitoring, optimism, state anxiety, trait anxiety, and depressive symptoms. Parents also completed a measure of their childs internalizing symptoms. As hypothesized, monitoring predicted increased trait anxiety and depressive symptoms, whereas optimism predicted decreased trait anxiety, state anxiety, depressive symptoms, and parent-rated internalizing symptoms. Age, gender, respiratory function, and socioeconomic status generally were unrelated to internalizing symptoms, with the exception that younger children had more trait anxiety but fewer parent-rated internalizing symptoms. Results suggest that monitoring and a lack of optimism may explain individual variation in internalizing symptoms among youths with chronic physical problems. Further research is needed to examine whether these factors precede increases in internalizing symptoms over time.

Daily spirometry in an acute exacerbation of adult cystic fibrosis patients

To help answer the question of length of intravenous antibiotics during an acute exacerbation of cystic fibrosis (CF), we had subjects to follow daily home spirometry while on intravenous antibiotics. CF patients, 18 and older, with an acute exacerbation requiring intravenous antibiotics had a daily FEV1. The average time to a 10% increase over their initial sick FEV1 was calculated, as well as the time to a new baseline. A total of 25 subjects completed the study. Ten of the 25 subjects did not have a sustainable 10% increase in FEV1. Of the 15 subjects with a sustainable 10% increase in FEV1, it took 5.2 days (±4.5) after day 1, while a new baseline was achieved on average at 6.6 days (±4.8) after day 1. Given the wide range of time to a 10% improvement and new baseline, it is recommended there should be flexibility in length of intravenous antibiotics in CF, not by a preset number.

Monitoring and Blunting as Predictors of Internalizing Symptoms Among Youths With Cystic Fibrosis

Monitoring and blunting are cognitive-affective informational processing styles that may predict future internalizing symptoms among youths with cystic fibrosis (CF). Forty-four youths with CF (9–23 years) and one of their parents completed measures of the youths’ monitoring, blunting, and internalizing symptoms at baseline and again two years later. Monitoring was associated with higher levels of concurrent internalizing symptoms on self- but not parent report, and did not predict changes in future symptoms. Blunting, in contrast, predicted a relative decrease in self-reported anxiety and depressive symptoms and in parent-report of youths’ depressive symptoms at Time 2. Our findings suggest that blunting may be an important protective factor in the adjustment of youths with CF.