Janice A. Espinola

Cord-Blood 25-Hydroxyvitamin D Levels and Risk of Respiratory Infection, Wheezing, and Asthma

OBJECTIVE: Higher maternal intake of vitamin D during pregnancy is associated with a lower risk of wheezing in offspring. The relationship between cord-blood levels of 25-hydroxyvitamin D (25[OH]D) and childhood wheezing is unknown. We hypothesized that cord-blood levels would be inversely associated with risk of respiratory infection, wheezing, and asthma. PATIENTS AND METHODS: Cord blood from 922 newborns was tested for 25(OH)D. Parents were asked if their child had a history of respiratory infection at 3 months of age or a history of wheezing at 15 months of age and then annually thereafter. Incident asthma was defined as doctor-diagnosed asthma by the time the child was 5 years old and reported inhaler use or wheezing since the age of 4 years. RESULTS: The median cord-blood level of 25(OH)D was 44 nmol/L (interquartile range: 29–78). Follow-up was 89% at the age of 5 years. Adjusting for the season of birth, 25(OH)D had an inverse association with risk of respiratory infection by 3 months of age (odds ratio: 1.00 [reference] for ≥75 nmol/L, 1.39 for 25–74 nmol/L, and 2.16 [95% confidence interval: 1.35–3.46] for <25 nmol/L). Likewise, cord-blood 25(OH)D levels were inversely associated with risk of wheezing by 15 months, 3 years, and 5 years of age (all P < .05). Additional adjustment for more than 12 potential confounders did not materially change these results. In contrast, we found no association between 25(OH)D levels and incident asthma by the age of 5 years. CONCLUSIONS: Cord-blood levels of 25(OH)D had inverse associations with risk of respiratory infection and childhood wheezing but no association with incident asthma.

Increased US Emergency Department Visits for Skin and Soft Tissue Infections, and Changes in Antibiotic Choices, During the Emergence of Community-Associated Methicillin-Resistant Staphylococcus aureus

STUDY OBJECTIVE Test the hypotheses that emergency department (ED) visits for skin and soft tissue infections became more frequent during the emergence of community-associated methicillin-resistant Staphylococcus aureus (MRSA), and that antibiotics typically active against community-associated MRSA were chosen increasingly. METHODS From merged National Hospital Ambulatory Medical Care Survey data for 1993-2005, we identified ED visits with diagnosis of cellulitis, abscess, felon, impetigo, hidradenitis, folliculitis, infective mastitis, nonpurulent mastitis, breast abscess, or carbuncle and furuncle. Main outcomes were change over time in rate of ED visits with such a diagnosis and proportion of antibiotic regimens including an agent typically active against community-associated MRSA. We report national estimates derived from sample weights. We tested trends with least squares linear regression. RESULTS In 1993, infections of interest were diagnosed at 1.2 million visits (95% confidence interval [CI] 0.96 to 1.5 million) versus 3.4 million in 2005 (95% CI 2.8 to 4.1 million; P for trend <.001). As a proportion of all ED visits, such infections were diagnosed at 1.35% in 1993 (95% CI 1.07% to 1.64%) versus 2.98% in 2005 (95% CI 2.40% to 3.56%; P for trend <.001). When antibiotics were prescribed at such visits, an antibiotic typically active against community-associated MRSA was chosen rarely from 1993 to 2001 but increasingly thereafter, reaching 38% in 2005 (95% CI 30% to 45%; P for trend <.001). In 2005, trimethoprim-sulfamethoxazole was used in 51% of regimens active against community-associated MRSA. CONCLUSION US ED visits for skin and soft tissue infections increased markedly from 1993 to 2005, contemporaneously with the emergence of community-associated MRSA. ED clinicians prescribed more antibiotics typically active against community-associated MRSA, especially trimethoprim-sulfamethoxazole. Possible confounders are discussed, such as increasing diabetes or shifts in locus of care.

Autophagy Is Disrupted in a Knock-in Mouse Model of Juvenile Neuronal Ceroid Lipofuscinosis

Juvenile neuronal ceroid lipofuscinosis is caused by mutation of a novel, endosomal/lysosomal membrane protein encoded by CLN3. The observation that the mitochondrial ATPase subunit c protein accumulates in this disease suggests that autophagy, a pathway that regulates mitochondrial turnover, may be disrupted. To test this hypothesis, we examined the autophagic pathway in Cln3Δex7/8 knock-in mice and CbCln3Δex7/8 cerebellar cells, accurate genetic models of juvenile neuronal ceroid lipofuscinosis. In homozygous knock-in mice, we found that the autophagy marker LC3-II was increased, and mammalian target of rapamycin was down-regulated. Moreover, isolated autophagic vacuoles and lysosomes from homozygous knock-in mice were less mature in their ultrastructural morphology than the wild-type organelles, and subunit c accumulated in autophagic vacuoles. Intriguingly, we also observed subunit c accumulation in autophagic vacuoles in normal aging mice. Upon further investigation of the autophagic pathway in homozygous knock-in cerebellar cells, we found that LC3-positive vesicles were altered and overlap of endocytic and lysosomal dyes was reduced when autophagy was stimulated, compared with wildtype cells. Surprisingly, however, stimulation of autophagy did not significantly impact cell survival, but inhibition of autophagy led to cell death. Together these observations suggest that autophagy is disrupted in juvenile neuronal ceroid lipofuscinosis, likely at the level of autophagic vacuolar maturation, and that activation of autophagy may be a prosurvival feedback response in the disease process.

Mutations in a novel CLN6-encoded transmembrane protein cause variant neuronal ceroid lipofuscinosis in man and mouse.

The CLN6 gene that causes variant late-infantile neuronal ceroid lipofuscinosis (vLINCL), a recessively inherited neurodegenerative disease that features blindness, seizures, and cognitive decline, maps to 15q21-23. We have used multiallele markers spanning this approximately 4-Mb candidate interval to reveal a core haplotype, shared in Costa Rican families with vLINCL but not in a Venezuelan kindred, that highlighted a region likely to contain the CLN6 defect. Systematic comparison of genes from the minimal region uncovered a novel candidate, FLJ20561, that exhibited DNA sequence changes specific to the different disease chromosomes: a G-->T transversion in exon 3, introducing a stop codon on the Costa Rican haplotype, and a codon deletion in exon 5, eliminating a conserved tyrosine residue on the Venezuelan chromosome. Furthermore, sequencing of the murine homologue in the nclf mouse, which manifests recessive NCL-like disease, disclosed a third lesion-an extra base pair in exon 4, producing a frameshift truncation on the nclf chromosome. Thus, the novel approximately 36-kD CLN6-gene product augments an intriguing set of unrelated membrane-spanning proteins, whose deficiency causes NCL in mouse and man.

A Nested Case-Control Study of Midgestation Vitamin D Deficiency and Risk of Severe Preeclampsia

CONTEXT Vitamin D may be important in the pathogenesis of severe preeclampsia. Given the few effective preventive strategies for severe preeclampsia, studies establishing this link are needed so that effective interventions can be developed. OBJECTIVE Our objective was to assess whether midgestation vitamin D deficiency is associated with development of severe preeclampsia. DESIGN AND SETTING We conducted a nested case-control study of pregnant women who had previously given blood for routine genetic multiple marker screening and subsequently delivered at a tertiary hospital between January 2004 and November 2008. PATIENTS Participants included women with singleton pregnancies in the absence of any chronic medical illnesses. From an overall cohort of 3992 women, 51 cases of severe preeclampsia were matched by race/ethnicity with 204 women delivering at term with uncomplicated pregnancies. Banked maternal serum was used to measure maternal 25-hydroxyvitamin D [25(OH)D]. MAIN OUTCOME MEASURE The main outcome was severe preeclampsia. RESULTS Midgestation maternal 25(OH)D concentration was lower in women who subsequently developed severe preeclampsia compared with controls [median (interquartile range), 75 (47-107) nmol/liter vs. 98 (68-113) nmol/liter; P = 0.01]. Midgestation maternal 25(OH)D of less than 50 nmol/liter was associated with an almost 4-fold odds of severe preeclampsia (unadjusted odds ratio, 3.63; 95% confidence interval, 1.52-8.65) compared with midgestation levels of at least 75 nmol/liter. Adjustment for known confounders strengthened the observed association (adjusted odds ratio, 5.41; 95% confidence interval, 2.02-14.52). CONCLUSION Maternal midgestation vitamin D deficiency was associated with increased risk of severe preeclampsia. Vitamin D deficiency may be a modifiable risk factor for severe preeclampsia.

Membrane trafficking and mitochondrial abnormalities precede subunit c deposition in a cerebellar cell model of juvenile neuronal ceroid lipofuscinosis

BackgroundJNCL is a recessively inherited, childhood-onset neurodegenerative disease most-commonly caused by a ~1 kb CLN3 mutation. The resulting loss of battenin activity leads to deposition of mitochondrial ATP synthase, subunit c and a specific loss of CNS neurons. We previously generated Cln3Δex7/8 knock-in mice, which replicate the common JNCL mutation, express mutant battenin and display JNCL-like pathology.ResultsTo elucidate the consequences of the common JNCL mutation in neuronal cells, we used P4 knock-in mouse cerebella to establish conditionally immortalized CbCln3 wild-type, heterozygous, and homozygous neuronal precursor cell lines, which can be differentiated into MAP-2 and NeuN-positive, neuron-like cells. Homozygous CbCln3Δex7/8 precursor cells express low levels of mutant battenin and, when aged at confluency, accumulate ATPase subunit c. Recessive phenotypes are also observed at sub-confluent growth; cathepsin D transport and processing are altered, although enzyme activity is not significantly affected, lysosomal size and distribution are altered, and endocytosis is reduced. In addition, mitochondria are abnormally elongated, cellular ATP levels are decreased, and survival following oxidative stress is reduced.ConclusionsThese findings reveal that battenin is required for intracellular membrane trafficking and mitochondrial function. Moreover, these deficiencies are likely to be early events in the JNCL disease process and may particularly impact neuronal survival.

Increasing Length of Stay Among Adult Visits to U.S. Emergency Departments, 2001–2005

BACKGROUND Emergency departments (EDs) are traditionally designed to provide rapid evaluation and stabilization and are neither staffed nor equipped to provide prolonged care. Longer ED length of stay (LOS) may compromise quality of care and contribute to delays in the emergency evaluation of other patients. OBJECTIVES The objective was to determine whether ED LOS increased between 2001 and 2005 and whether trends varied by patient and hospital factors. METHODS This was a retrospective analysis of a nationally representative sample of 138,569 adult ED visits from the National Hospital Ambulatory Medical Care Survey (NHAMCS), 2001 to 2005. ED LOS was measured from registration to discharge. RESULTS Median ED LOS increased 3.5% per year from 132 minutes in 2001 to 154 minutes in 2005 (p-value for trend < 0.001). There was a larger increase among critically ill patients for whom ED LOS increased 7.0% annually from 185 minutes in 2001 to 254 minutes in 2005 (p-value for trend < 0.01). ED LOS was persistently longer for black/African American, non-Hispanic patients (10.6% longer) and Hispanic patients (13.9% longer) than for non-Hispanic white patients, and these differences did not diminish over time. Among factors potentially associated with increasing ED LOS, a large increase was found (60.1%, p-value for trend < 0.001) in the use of advanced diagnostic imaging (computed tomography [CT], magnetic resonance imaging [MR], and ultrasound [US]) and in the proportion of ED visits at which five or more diagnostic or screening tests were ordered (17.6% increase, p-value for trend = 0.001). The proportion of uninsured patients was stable throughout the study period, and EDs with predominately privately insured patients experienced significant increases in ED LOS (4.0% per year from 2001 to 2005, p-value for trend < 0.01). CONCLUSIONS Emergency department LOS in the United States is increasing, especially for critically ill patients for whom time-sensitive interventions are most important. The disparity of longer ED LOS for African Americans and Hispanics is not improving.

Improved overall trends but persistent racial disparities in emergency department visits for acute asthma, 1993-2005.

BACKGROUND Emergency department (ED) visits for acute asthma provide an important marker of morbidity. OBJECTIVE To describe the epidemiology of ED visits for acute asthma. METHODS We obtained data from the National Hospital Ambulatory Medical Care Survey, 1993 to 2005, and used the primary diagnosis code for asthma (493) to identify cases. We calculated national estimates by using assigned patient visit weights and national rates per 1000 US population with demographic-specific population data from the US Census Bureau. RESULTS From 1993 to 2005, there were approximately 23,800,000 asthma visits, representing 1.8% of all ED visits, or an overall rate of 6.7 visits per 1000 US population. The national visit rate rose between 1993 and 1998 (P(trend) = .05), but was stable (or possibly decreasing) from 1998 to 2005 (P(trend) = .07). Although rates for white subjects decreased by 25% from 1998 to 2005 (P(trend) = .02), the rates for black subjects remained constant (P(trend) = .80). The overall asthma-related ED visit rate was highest among the following groups: age <10 years (13), women (7.2), black subjects (19), Hispanic subjects (7.1), and subjects in the Northeast (9.2). ED administration of inhaled anticholinergic agents increased 20-fold and systemic corticosteroids increased 2-fold from 1993 to 2005 (P(trend) = .02 and .03, respectively), whereas inhaled beta-agonist and inhaled corticosteroid administration was stable (P(trend) = .09 and .34, respectively). CONCLUSION Although asthma-related ED visit rates showed a significant upward trend from 1993 to 1998, our results support the emerging view that the asthma epidemic may have reached a plateau. Nevertheless, the higher visit rates observed among specific demographic groups and widening disparities, particularly among black subjects, remain problematic and warrant further investigation.

Prospective Multicenter Study of Children With Bronchiolitis Requiring Mechanical Ventilation

OBJECTIVE: To identify factors associated with continuous positive airway pressure (CPAP) and/or intubation for children with bronchiolitis. METHODS: We performed a 16-center, prospective cohort study of hospitalized children aged <2 years with bronchiolitis. For 3 consecutive years from November 1 until March 31, beginning in 2007, researchers collected clinical data and a nasopharyngeal aspirate from study participants. We oversampled children from the ICU. Samples of nasopharyngeal aspirate were tested by polymerase chain reaction for 18 pathogens. RESULTS: There were 161 children who required CPAP and/or intubation. The median age of the overall cohort was 4 months; 59% were male; 61% white, 24% black, and 36% Hispanic. In the multivariable model predicting CPAP/intubation, the significant factors were: age <2 months (odds ratio [OR] 4.3; 95% confidence interval [CI] 1.7–11.5), maternal smoking during pregnancy (OR 1.4; 95% CI 1.1–1.9), birth weight <5 pounds (OR 1.7; 95% CI 1.0–2.6), breathing difficulty began <1 day before admission (OR 1.6; 95% CI 1.2–2.1), presence of apnea (OR 4.8; 95% CI 2.5–8.5), inadequate oral intake (OR 2.5; 95% CI 1.3–4.3), severe retractions (OR 11.1; 95% CI 2.4–33.0), and room air oxygen saturation <85% (OR 3.3; 95% CI 2.0–4.8). The optimism-corrected c-statistic for the final model was 0.80. CONCLUSIONS: In this multicenter study of children hospitalized with bronchiolitis, we identified several demographic, historical, and clinical factors that predicted the use of CPAP and/or intubation, including children born to mothers who smoked during pregnancy. We also identified a novel subgroup of children who required mechanical respiratory support <1 day after respiratory symptoms began.

Vitamin D Status and Periodontal Disease Among Pregnant Women

BACKGROUND Maternal periodontal disease is found in < or = 40% of pregnant women and is associated with adverse pregnancy outcomes. Vitamin D deficiency may play a role in periodontal disease and tooth loss, and insufficient vitamin D status is common among pregnant women. The objective of this study is to examine the relationship between maternal vitamin D status and periodontal disease. METHODS A case-control study was conducted. Cases were defined as pregnant women with clinical moderate to severe periodontal disease; controls were pregnant women who were periodontally healthy. Maternal data were chart abstracted and serum was collected between 14 and 26 weeks of gestation. Serum 25-hydroxyvitamin D (25[OH]D) levels were measured using liquid chromatography-tandem mass spectrometry. Median serum 25(OH)D levels and prevalence of vitamin D insufficiency (defined as <75 nmol/l) were compared between cases and controls. The odds ratio and 95% confidence interval for moderate to severe periodontal disease among women with vitamin D insufficiency was calculated using multivariable logistic regression, adjusting for maternal race, season of blood draw, and other potential confounders. RESULTS A total of 117 cases were compared to 118 controls. Cases had lower median 25(OH)D levels than controls (59 versus 100 nmol/l; P <0.001) and were more likely to have vitamin D insufficiency (65% versus 29%; P <0.001). The adjusted odds ratio (95% confidence interval) for moderate to severe periodontal disease among women with vitamin D insufficiency was 2.1 (0.99 to 4.5). CONCLUSIONS Vitamin D insufficiency (serum 25[OH]D <75 nmol/l) is associated with maternal periodontal disease during pregnancy. Vitamin D supplementation represents a potential therapeutic strategy to improve maternal oral health.