Short-term outcomes comparison between preterm infants with and without acute hypoxic respiratory failure attributable to presumed pulmonary hypoplasia after prolonged preterm premature rupture of membranes before 25 gestational weeks.

OBJECTIVE: To determine the updated outcomes of preterm infants with acute hypoxic respiratory failure attributable to presumed pulmonary hypoplasia (PH) following maternal midtrimester prolonged preterm premature rupture of membranes (PPROM). STUDY DESIGN: Among preterm infants with birthweight <1500 g and 23-34 weeks gestational age in a single center, infants exposed to maternal prolonged (≥7 days) PPROM before 25 gestational weeks (PPPROM25, n = 76) were retrospectively reviewed. They were 1:1 matched with infants of matched control group (n = 76) who were unexposed to or exposed to maternal PPROM within 24 hours of delivery by year, gestational age, and weight at birth, sex, and antenatal steroid exposure. The PPPROM25 group was subdivided into infants with and without acute hypoxic respiratory failure attributable to PH (with PH, n = 20, without PH, n = 56, respectively). Clinical characteristics and major outcomes were compared. Risk factors for mortality and morbidity were analyzed using a multivariate logistic regression in the PPPROM25 group. RESULTS: The PH incidence rates were 1.3 and 26.3% and in the matched control and PPPROM25 group, respectively (p < .05). The survival rates were 92.1 and 81.6% in the matched control and PPPROM25 group (p > .05); 87.5 in the PPPROM25 group without PH and 65.0% in group with PH, respectively (p < .05). While there were no significant differences between matched control and PPROM25 group, the PPROM25 with PH group had a significantly higher rate of periventricular leukomalacia (PVL) and composite morbidity, including mortality, bronchopulmonary dysplasia, high-grade intraventricular hemorrhage, and PVL than PPPROM25 without PH group. PH was a significant risk factor for mortality and composite morbidity in the PPPROM25 group. CONCLUSIONS: Despite the improved outcomes in the infants with maternal prolonged PPROM before 25 gestational weeks, presumed PH is still a significant risk factor for their mortality and morbidity.

The Youngest Survivor with Gestational Age of 215/7 Weeks.

The decision whether or not to resuscitate extremely low gestational age (GA) infants is recommended to be individualized according to antenatal counseling with parents, neonatologists, and obstetricians. A GA of 22°/7-236/7 weeks is generally considered as the lower end of the range where infants can be candidates for selective resuscitation. Below this lower end of periviable gestation, resuscitation is usually not considered and survivors are rarely reported. To date, the youngest survivor is an infant with a GA of 216/7 weeks reported in the English medical literature. Here, we report the case of a female infant, the first twin conceived through in vitro fertilization, with a GA of 215/7 weeks, who was resuscitated initially according to strong parental wishes after antenatal counseling and is still surviving at 43 months of age with fairly good neurodevelopmental outcome.

A Novel De Novo Pathogenic Variant in FOXF1 in a Newborn with Alveolar Capillary Dysplasia with Misalignment of Pulmonary Veins.

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is an autosomal dominant, fatal developmental disorder of the lungs, with a mortality rate of about 100%. ACD/MPV is caused by mutations in FOXF1. Herein, we describe a newborn boy with ACD/MPV carrying a novel pathogenic variant of FOXF1. The patient developed respiratory distress and severe pulmonary hypertension on the first day of life. Despite aggressive cardiorespiratory management, including veno-venous extracorporeal membrane oxygenation, his condition deteriorated rapidly, and he died within the first month of his life. Lung histology showed the characteristic features of ACD/MPV at autopsy. Sequence analysis of FOXF1 from genomic DNA obtained from autopsied lung tissue revealed that the patient was heterozygous for a novel missense variant (c.305T>C; p.Leu102Pro). Further analysis of both parents confirmed the de novo occurrence of the variant. To the best of our knowledge, this is the first report of genetically confirmed ACD/MPV in Korea.

Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis Associated with Acetaminophen Use during Viral Infections.

An association between drug treatment for viral infections and severe cutaneous adverse reactions has been noted. We investigated six patients diagnosed with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) after being prescribed acetaminophen for suspected viral illnesses. Multiplex analysis was performed to measure cytokine levels in sera before and after treatment. IL-2Rα levels significantly decreased during the convalescence phase. Although acetaminophen is relatively safe, the drug can trigger SJS/TEN in patients with suspected viral infections. T-cells and monocytes may be key components of the link between viral infection and acetaminophen-induced SJS/TEN.

Mandatory Closure Versus Nonintervention for Patent Ductus Arteriosus in Very Preterm Infants.

OBJECTIVE: To determine whether a nonintervention approach for treating hemodynamically significant patent ductus arteriosus (PDA) is associated with decreased mortality and/or morbidity compared with a mandatory closure approach in extremely low birth weight infants. STUDY DESIGN: We reviewed the medical records of 178 infants of 23-26 weeks' gestational age with PDA, requiring ventilator treatment, and with hemodynamically significant PDA ≥2 mm in size. Mandatory closure was used during period I (July 2009 to December 2011, n = 81), and nonintervention was used during period II (January 2012 to June 2014, n = 97). RESULTS: During period I, 64% of infants were first treated with indomethacin, and 82% were ultimately ligated surgically. During period II, no infant was treated with indomethacin and/or ligation. The average postnatal day of PDA closure was day 13 and day 44 during periods I and II, respectively. There was significantly more use of diuretics and fluid restriction during period II compared with period I. There was no difference in mortality or morbidities such as necrotizing enterocolitis or intraventricular hemorrhage. The incidence of bronchopulmonary dysplasia (BPD) and the propensity score adjusted OR of BPD were significantly lower during period II compared with period I. CONCLUSIONS: Despite longer PDA exposure, nonintervention was associated with significantly less BPD compared with mandatory closure. Additional study is warranted to determine the benefits and risks of non-intervention for the hemodynamically significant PDA in extremely low birth weight infants.

Intratracheal transplantation of mesenchymal stem cells simultaneously attenuates both lung and brain injuries in hyperoxic newborn rats.

BACKGROUND: Bronchopulmonary dysplasia is an independent risk factor for adverse neurodevelopmental outcomes in premature infants. We investigated whether attenuation of hyperoxic lung injury with intratracheal transplantation of human umbilical cord blood-derived mesenchymal stem cells (MSCs) could simultaneously mitigate brain damage in neonatal rats. METHODS: Newborn Sprague-Dawley rats were exposed to hyperoxia or normoxia conditions for 14 d. MSCs (5 × 10(5) cells) were transplanted intratracheally at postnatal day (P) 5. At P14, lungs and brains were harvested for histological and biochemical analyses. RESULTS: Hyperoxic lung injuries, such as impaired alveolarization evident from increased mean linear intercept (MLI) and elevated inflammatory cytokine levels were significantly alleviated with MSC transplantation. Hyperoxia decreased brain weight, increased brain cell death, and induced hypomyelination. MSC transplantation significantly ameliorated hyperoxia-induced increased terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells in the dentate gyrus and reduced myelin basic protein. In correlation analyses, brain weight and myelin basic protein (MBP) were significantly inversely correlated with lung MLI and inflammatory cytokines, while TUNEL-positive brain cell number showed a significant positive correlation with lung MLI. CONCLUSION: Despite no significant improvement in short-term neurofunctional outcome, intratracheal transplantation of MSCs simultaneously attenuated hyperoxic lung and brain injuries in neonatal rats, with the extent of such attenuation being closely linked in the two tissues.

Trends in Survival and Incidence of Bronchopulmonary Dysplasia in Extremely Preterm Infants at 23-26 Weeks Gestation.

The aim of this study was to investigate the relationship between survival and incidence of bronchopulmonary dysplasia (BPD) in extremely premature infants, and identify clinical factors responsible for this association. Medical records of 350 infants at 23-26 weeks gestation from 2000 to 2005 (period I, n = 137) and 2006 to 2010 (period II, n = 213) were retrospectively reviewed. The infants were stratified into 23-24 and 25-26 weeks gestation, and the survival, BPD incidence, and clinical characteristics were analyzed. BPD was defined as oxygen dependency at 36 weeks postmenstrual age. The overall survival rate was significantly improved in period II compared to period I (80.3% vs. 70.0%, respectively; P = 0.028), especially in infants at 23-24 weeks gestation (73.9% vs. 47.4%, respectively; P = 0.001). The BPD incidence in survivors during period II (55.0%) was significantly decreased compared to period I (67.7%; P = 0.042), especially at 25-26 weeks gestation (41.7% vs. 62.3%, respectively; P = 0.008). Significantly improved survival at 23-24 weeks gestation was associated with a higher antenatal steroid use and an improved 5-minute Apgar score. A significant decrease in BPD incidence at 25-26 weeks gestation was associated with early extubation, prolonged use of less invasive continuous positive airway pressure, and reduced supplemental oxygen. Improved perinatal and neonatal care can simultaneously lead to improved survival and decreased BPD incidence in extremely premature infants.

Optimal Timing of Mesenchymal Stem Cell Therapy for Neonatal Intraventricular Hemorrhage.

We recently showed that intraventricular transplantation of human umbilical cord blood (UCB)-derived mesenchymal stem cells (MSCs) significantly attenuated posthemorrhagic hydrocephalus (PHH) and brain injury after severe intraventricular hemorrhage (IVH) in newborn rat pups. The purpose of this study was to optimize the timing of MSC transplantation for severe IVH. Severe IVH was induced by injecting 100 µl of blood into each ventricle of Sprague-Dawley rats on postnatal day 4 (P4). Human UCB-derived MSCs (1 × 10(5) cells in 10 µl of normal saline) were transplanted intraventricularly under stereotaxic guidance either early at P6 or late at P11. Serial brain MRIs and behavioral function tests, such as negative geotaxis and rotarod tests, were performed. At P32, brain tissue samples were obtained for histological and biochemical analyses. Intracerebroventricular transplantation of MSCs significantly attenuated the development of PHH, behavioral impairment, increased apoptosis and astrogliosis, reduced corpus callosum thickness and brain myelination, and upregulated inflammatory cytokines including interleukin (IL)-1α, IL-1ß, IL-6, and tumor necrosis factor-α (TNF-α) at P6 but not at P11 after induction of severe IVH. Intracerebroventricular transplantation of human UCB-derived MSCs attenuated PHH and brain injury after severe IVH in newborn rats in a time-dependent manner. Significant neuroprotection was only demonstrated when administered early at 2 days after induction but not late at 7 days after induction of severe IVH.

Antibacterial effect of mesenchymal stem cells against Escherichia coli is mediated by secretion of beta- defensin- 2 via toll- like receptor 4 signalling.

Recently, we demonstrated that intratracheal transplantation of human umbilical cord blood- derived mesenchymal stem cells (MSCs) attenuates Escherichia (E) coli- induced acute lung injury primarily by down- modulating inflammation and enhancing bacterial clearance iQn mice. This study was performed to elucidate the mechanism underlying the antibacterial effects of MSCs. The growth of E. coli in vitro was significantly inhibited only by MSCs or their conditioned medium with bacterial preconditioning, but not by fibroblasts or their conditioned medium. Microarray analysis identified significant up- regulation of toll- like receptors (TLR)- 2 and TLR- 4, and ß- defensin 2 (BD2) in MSCs compared with fibroblasts after E. coli exposure. The increased BD2 level and the in vitro antibacterial effects of MSCs were abolished by specific antagonist or by siRNA- mediated knockdown of TLR- 4, but not TLR- 2, and restored by BD2 supplementation. The in vivo down- modulation of the inflammatory response and enhanced bacterial clearance, increased BD2 secretion and the resultant protection against E. coli- induced pneumonia observed only with MSCs, but not fibroblasts, transplantation in mice, were abolished by knockdown of TLR- 4 with siRNA transfection. Our data indicate that BD2 secreted by the MSCs via the TLR- 4 signalling pathway is one of the critical paracrine factors mediating their microbicidal effects against E. coli, both in vitro and in vivo. Furthermore, TLR- 4 from the transplanted MSCs plays a seminal role in attenuating in vivo E. coli- induced pneumonia and the ensuing acute lung injury through both its anti- inflammatory and antibacterial effects.

Optimal Route for Human Umbilical Cord Blood-Derived Mesenchymal Stem Cell Transplantation to Protect Against Neonatal Hyperoxic Lung Injury: Gene Expression Profiles and Histopathology.

The aim of this study was to determine the optimal route of mesenchymal stem cell (MSC) transplantation. To this end, gene expression profiling was performed to compare the effects of intratracheal (i.t.) versus intravenous (i.v.) MSC administration. Furthermore, the therapeutic efficacy of each route to protect against neonatal hyperoxic lung injury was also determined. Newborn Sprague-Dawley rats were exposed to hyperoxia (90% oxygen) from birth for 14 days. Human umbilical cord blood-derived MSCs labeling with PKH26 were transplanted through either the i.t. (5×10(5)) or i.v. (2×10(6)) route at postnatal day (P) 5. At P14, lungs were harvested for histological, biochemical and microarray analyses. Hyperoxic conditions induced an increase in the mean linear intercept and mean alveolar volume (MAV), indicative of impaired alveolarization. The number of ED-1 positive cells was significantly decreased by both i.t. and i.v. transplantations. However, i.t. administration of MSCs resulted in a greater decrease in MAV and ED-1 positive cells compared to i.v. administration. Moreover, the number of TUNEL-positive cells was significantly decreased in the i.t. group, but not in the i.v. group. Although the i.t. group received only one fourth of the number of MSCs that the i.v. group did, a significantly higher number of donor cell-derived red PKH 26 positivity were recovered in the i.t. group. Hyperoxic conditions induced the up regulation of genes associated with the inflammatory response, such as macrophage inflammatory protein-1 α, tumor necrosis factor-α and inter leukin-6; genes associated with cell death, such as p53 and caspases; and genes associated with fibrosis, such as connective tissue growth factor. In contrast, hyperoxic conditions induced the dwon-regulation of vascular endothelial growth factor and hepatocyte growth factor. These hyperoxia-induced changes in gene expression were decreased in the i.t. group, but not in the i.v. group. Thus, local i.t. MSC transplantation was more effective than systemic i.v. MSC administration in protecting against neonatal hyperoxic lung injury.

Optimal Route for Mesenchymal Stem Cells Transplantation after Severe Intraventricular Hemorrhage in Newborn Rats.

Recently, we showed that intracerebroventricular (IC) transplantation of human umbilical cord blood (UCB)-derived mesenchymal stem cells (MSCs) significantly attenuates posthemorrhagic hydrocephalus (PHH) and brain damage after severe IVH in newborn rats. This study was performed to determine the optimal route for transplanting MSCs for severe IVH by comparing IC transplantation, intravenous (IV) transplantation, and IV transplantation plus mannitol infusion. Severe IVH was induced by injecting 100 uL of blood into each ventricle of Sprague-Dawley rats on postnatal day 4 (P4). After confirming severe IVH with brain magnetic resonance imaging (MRI) at P5, human UCB-derived MSCs were transplanted at P6 by an IC route (1×105), an IV route (5×105), or an IV route with mannitol infused. Follow-up brain MRIs and rotarod tests were performed. At P32, brain tissue samples were obtained for biochemical and histological analyses. Although more MSCs localized to the brain after IC than after IV delivery, both methods were equally effective in preventing PHH; attenuating impaired rotarod test; increasing the number of TUNEL-positive cells, inflammatory cytokines, and astrogliosis; and reducing corpus callosal thickness and myelin basic protein expression after severe IVH regardless of mannitol co-infusion. Despite the superior delivery efficacy with IC than with the IV route, both IC and IV transplantation of MSCs had equal therapeutic efficacy in protecting against severe IVH. These findings suggest that the less invasive IV route might be a good alternative for clinically unstable, very preterm infants that cannot tolerate a more invasive IC delivery of MSCs.

Effect of Prophylactic Palivizumab on Admission Due to Respiratory Syncytial Virus Infection in Former Very Low Birth Weight Infants with Bronchopulmonary Dysplasia.

The aim of this study was to observe the effects of prophylactic palivizumab on hospitalization secondary to respiratory syncytial virus (RSV) infection (RSVhospitalization) in former very low birth weight infants (VLBWI) with bronchopulmonary dysplasia (BPD). This study also sought to identify the risk factors of RSVhospitalizationin this particular infant population. A prospective observational study was conducted between September 2007 and April 2008 in seven Korean hospitals. Children with a history of very low birth weight, a diagnosis of BPD and who were <2 yr old at the onset of the RSV season were included in this study. Palivizumab injections were administered monthly for a maximum of five months during the RSV season. RSVhospitalization rates were reviewed, and RSVhospitalization rates between subgroups were categorized by gestational age, birth weight, and duration of ventilator care. A total of 90 subjects completed the follow-up interviews. The mean gestational age at birth was 26.1±1.7 weeks, and the mean birth weight was 889.4±222.2 g. The incidence of RSVhospitalization in the study population was 8.9% (8/90), and the mean hospital stay was 11.0±5.5 days, including one death. There were no statistically significant differences in the patients' demographic characteristics or risk factors for RSV hospitalization. When subgroup analyses were conducted, there were still no statistically significant differences. The administration of palivizumab prophylaxis during the entire RSV season is important in VLBWI with BPD, regardless of their gestational age and birth weight, or previous ventilator dependency.

Prevention of Cytomegalovirus Transmission via Breast Milk in Extremely Low Birth Weight Infants.

PURPOSE: Extremely low birth weight infants (ELBWIs) have a high risk of acquiring cytomegalovirus (CMV) infection via breast milk and consequently developing serious symptoms. We evaluated whether freeze-thawing or pasteurization could prevent postnatal CMV infection transmitted through breast milk in ELBWIs. MATERIALS AND METHODS: Medical records of 385 ELBWIs with whole milk feeding, and freeze-thawed or pasteurized breast milk feeding were reviewed retrospectively. Postnatally acquired CMV infection was defined as an initial negative and a subsequent positive on follow-up urine CMV DNA polymerase chain reaction screening tests. The incidence, clinical characteristics, symptoms, sequelae, and long-term outcome at corrected age [(CA): 2 years of CMV infection] were analyzed. RESULTS: While no infant developed CMV infection with whole milk (0/22) or pasteurized breast milk (0/62) feeding, postnatal CMV infection was diagnosed in 8% (27/301) of ELBWIs who were fed freeze-thawed breast milk. Gestational age in the CMV group was significantly lower than the control group. In 82% (22/27) of cases, CMV infection was symptomatic and was associated with increased ventilator days and ≥moderate bronchopulmonary dysplasia (BPD). Neurodevelopmental outcome and growth status at CA 2 years were not different between the study groups. Lower gestational age and freeze-thawed breast milk feeding >60% of total oral intake during the first 8 postnatal weeks were independent risk factors for acquiring postnatal CMV infection. BPD (≥moderate) was the only significant adverse outcome associated with this CMV infection. CONCLUSION: Pasteurization but not freeze-thawing of breast milk eradicated the postnatal acquisition of CMV infection through breast milk.

Cell type-dependent variation in paracrine potency determines therapeutic efficacy against neonatal hyperoxic lung injury.

BACKGROUND AIMS: The aim of this study was to determine the optimal cell type for transplantation to protect against neonatal hyperoxic lung injury. To this end, the in vitro and in vivo therapeutic efficacies and paracrine potencies of human umbilical cord blood-derived mesenchymal stromal cells (HUMs), human adipose tissue-derived mesenchymal stromal cells (HAMs) and human umbilical cord blood mononuclear cells (HMNs) were compared. METHODS: Hyperoxic injury was induced in vitro in A549 cells by challenge with H2O2. Alternatively, hyperoxic injury was induced in newborn Sprague-Dawley rats in vivo by exposure to hyperoxia (90% oxygen) for 14 days. HUMs, HAMs or HMNs (5 × 10(5) cells) were given intratracheally at postnatal day 5. RESULTS: Hyperoxia-induced increases in in vitro cell death and in vivo impaired alveolarization were significantly attenuated in both the HUM and HAM groups but not in the HMN group. Hyperoxia impaired angiogenesis, increased the cell death and pulmonary macrophages and elevated inflammatory cytokine levels. These effects were significantly decreased in the HUM group but not in the HAM or HMN groups. The levels of human vascular endothelial growth factor and hepatocyte growth factor produced by donor cells were highest in HUM group, followed by HAM group and then HMN group. CONCLUSIONS: HUMs exhibited the best therapeutic efficacy and paracrine potency than HAMs or HMNs in protecting against neonatal hyperoxic lung injury. These cell type-dependent variations in therapeutic efficacy might be associated or mediated with the paracrine potency of the transplanted donor cells.

Hypothermia augments neuroprotective activity of mesenchymal stem cells for neonatal hypoxic-ischemic encephalopathy.

Though hypothermia is the only clinically available treatment for neonatal hypoxic-ischemic encephalopathy (HIE), it is not completely effective in severe cases. We hypothesized that combined treatment with hypothermia and transplantation of human umbilical cord blood (UCB)-derived mesenchymal stem cells (MSCs) would synergistically attenuate severe HIE compared to stand-alone therapy. To induce hypoxia-ischemia (HI), male Sprague-Dawley rats were subjected to 8% oxygen for 120 min after unilateral carotid artery ligation on postnatal day (P) 7. After confirmation of severe HIE involving >50% of the ipsilateral hemisphere volume as determined by diffusion-weighted brain magnetic resonance imaging (MRI) within 2 h after HI, intraventricular MSC transplantation (1 × 105 cells) and/or hypothermia with target temperature at 32°C for 24 h were administered 6 h after induction of HI. Follow-up brain MRI at P12 and P42, sensorimotor function tests at P40-42, evaluation of cytokines in the cerebrospinal fluid (CSF) at P42, and histologic analysis of peri-infarct tissues at P42 were performed. Severe HI resulted in progressively increased brain infarction over time as assessed by serial MRI, increased number of cells positive for terminal deoxynucleotidyl transferase nick-end labeling, microgliosis and astrocytosis, increased CSF cytokine levels, and impaired function in behavioral tests such as rotarod and cylinder tests. All of the abnormalities observed in severe HIE showed greater improvement after combined treatment with hypothermia and MSC transplantation than with either therapy alone. Overall, these findings suggest that combined treatment with hypothermia and human UCB-derived MSC transplantation might be a novel therapeutic modality to improve the prognosis of severe HIE, an intractable disease that currently has no effective treatment.

Immunologic evaluation of patients with cefotetan-induced anaphylaxis.

Cefotetan is a commonly prescribed second-generation cephalosporin that acts against a wide range of bacteria. However, cefotetan-induced hypersensitivity has rarely been reported. We report 2 cases of cefotetan-induced anaphylaxis with immunologic evaluation. The first case was a 70-year-old asthmatic woman who had dyspnea and hypotension during administration of cefotetan, in which high serum-specific IgE to cefotetan-human serum albumin (HSA) conjugate was detected by enzyme-linked immunosorbent assay. The second case was a 63-year-old asthmatic woman who complained of chest tightness and dyspnea during cefotetan infusion, in which high serum-specific IgG1 and IgG4 with no serum specific IgE to cefotetan-HSA conjugate was detected. The basophil activation test using basophils from the patient showed a significant up-regulation of CD63 with the addition of anti-IgG4 antibody compared with that in non-atopic healthy controls. In conclusion, cefotetan can induce anaphylaxis, which may involve both IgE- and IgG4-mediated responses in the pathogenic mechanism.

Clinical features of elderly chronic urticaria.

BACKGROUND/AIMS: Chronic urticaria (CU) is defined as itchy wheals lasting 6 weeks or more. As the aged population increases worldwide, it is essential to identify the specific features of this disease in the elderly population. METHODS: We investigated the prevalence and clinical features of CU in elderly patients. Medical records of 837 CU patients from the outpatient Allergy Clinic of Ajou University Hospital, Korea were analyzed retrospectively. Patients with chronic spontaneous urticaria according to the EAACI/GA2LEN/EDF/WAO guidelines were included. Patients older than 60 years were defined as elderly. RESULTS: Of the 837 patients, 37 (4.5%) were elderly. In elderly versus nonelderly CU patients, the prevalence of atopic dermatitis (AD) was significantly higher (37.8% vs. 21.7%, respectively; p = 0.022), while that of aspirin intolerance was lower (18.9% vs. 43.6%, respectively; p = 0.003) in terms of comorbid conditions. The prevalences of serum specific immunoglobulin E antibodies to staphylococcal enterotoxin A and staphylococcal enterotoxin B were considerably higher in elderly CU patients with AD than in those without AD (37.5% vs. 0%, respectively). CONCLUSIONS: Elderly patients with CU had a higher prevalence of AD. Therefore, there is a need to recognize the existence of AD in elderly CU patients.

Immunologic evaluation of immediate hypersensitivity to cefaclor.

PURPOSE: Cefaclor is widely prescribed for various infectious diseases. As its consumption increases, the number of hypersensitivity reactions to cefaclor has increased. This study aimed to evaluate the immunologic findings of immediate hypersensitivity to cefaclor. MATERIALS AND METHODS: We enrolled 47 patients with immediate hypersensitivity to cefaclor from Ajou University Hospital and Asan Medical Center. Serum specific IgE, IgG1, and IgG4 antibodies to cefaclor-human serum albumin (HSA) conjugate were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The most common phenotype was anaphylaxis (Group I, 78.7%), followed by urticaria (Group II, 21.3%). The detection of specific IgE, IgG1, and IgG4 to cefaclor-HSA conjugate by ELISA tended to be higher in Group I (40.5%, 41.7%, 21.6%) than in Group II (20.0%, 20.0%, 0%) with no statistical significance. Significant associations were found between specific IgE and IgG1 or IgG4 (p<0.001, p=0.019). ELISA inhibition tests showed significant inhibitions by both free cefaclor and cefaclor-HSA conjugate. For basophil activation tests in patients having no specific IgE antibody, the CD63 expression level on basophils increased with incubations of free cefaclor. CONCLUSION: The most common manifestation of immediate hypersensitivity to cefaclor was anaphylaxis, most of which was mediated by IgE; however, a non-IgE mediated direct basophil activation mechanism was suggested in a subset of anaphylaxis patients.

Association of serum periostin with aspirin-exacerbated respiratory disease.

BACKGROUND: Recent studies recommend periostin as a systemic biomarker of eosinophilic airway inflammation to predict responses to novel treatments that targets eosinophilic TH2-driven inflammation in asthmatic patients. OBJECTIVE: To investigate the clinical implications of serum periostin levels in patients with aspirin-exacerbated respiratory disease (AERD) based on its overlapping TH2-mediated pathogenesis with the eosinophilic asthma. METHODS: Serum periostin levels were measured by human periostin enzyme-linked immunosorbent assay (ELISA) in serum samples from 277 adults with asthma. Serum periostin levels were compared between patients with AERD and aspirin tolerant asthma (ATA) with other asthma phenotypes, such as severe or nonsevere asthma and eosinophilic or noneosinophilic asthma. The association of serum periostin levels with clinical parameters (including disease severity and comorbid condition) was analyzed. RESULTS: Serum periostin levels were significantly higher in patients with AERD vs ATA, patients with severe asthma vs nonsevere asthma, and patients with eosinophilic asthma vs noneosinophilic asthma (P=.005, P=.02, and P=.001, respectively). Multivariate regression analysis revealed serum periostin levels as a significant parameter to predict AERD phenotype (P=.006) together with severe asthma phenotype (P=.04). In addition, serum periostin levels correlated with blood eosinophil counts (Spearman ñ = 0.244, P<.001) and sputum eosinophil counts (Spearman ñ = 0.261, P < 0.001). Higher serum periostin levels were noted in comorbid AERD patients with more severe chronic rhinosinusitis (Lund-Mackay stages 3 and 4) than those with less severe chronic rhinosinusitis (Lund-Mackay stages 1 and 2) (P = .03). CONCLUSION: Serum periostin levels are significantly elevated in AERD patients and associated with AERD phenotype and disease severity.

Elevated platelet activation in patients with chronic urticaria: a comparison between aspirin-intolerant and aspirin-tolerant groups.

BACKGROUND: Platelets are actively involved in immune inflammatory processes that release inflammatory mediators. Platelet activation has been reported in various inflammatory diseases; however, few studies have described platelet involvement in chronic urticaria (CU). OBJECTIVE: To investigate platelet-activation markers, namely P2Y12 receptor and P-selectin expression, and soluble P-selectin level in patients with aspirin-intolerant CU (AICU) and aspirin-tolerant CU (ATCU). METHODS: Forty-eight patients with CU and 25 normal controls were enrolled in this study. Aspirin intolerance in patients with CU was confirmed by an oral provocation test. P2Y12 and P-selectin expressions on platelets were measured using flow cytometry; soluble P-selectin level in plasma was measured by enzyme-linked immunosorbent assay. To study the functional effects of aspirin, platelets were treated with aspirin (2 mmol/L) and the expressions of P2Y12 and P-selectin were compared between the AICU and ATCU groups. RESULTS: The expression of P2Y12 was significantly higher in patients with CU compared with controls, whereas no significant difference was noted in the expression of P-selectin level. The levels were not significantly different according to urticaria symptom score, symptom control status, and aspirin intolerance. Soluble P-selectin level was significantly higher in the AICU group than in the ATCU group compared with controls. Aspirin did not significantly suppress P2Y12 and P-selectin expressions on platelets in the AICU group, whereas significant suppression was noted in the ATCU group. CONCLUSION: These findings suggest that increased platelet activation contributes to skin inflammation in patients with AICU and those with ATCU. The functional difference of platelets in response to aspirin may contribute to persistent skin inflammation in patients with AICU.