Suh Young Lee

Cross-reactivity to Acetaminophen and Celecoxib According to the Type of Nonsteroidal Anti-inflammatory Drug Hypersensitivity

Purpose Identification of tolerable alternative analgesics is crucial for management in nonsteroidal anti-inflammatory drug (NSAID)-sensitive patients. We investigated cross-reactivity of acetaminophen and celecoxib according to the type of aspirin/NSAID hypersensitivity and aimed to determine the risk factors for cross-intolerance. Methods We retrospectively reviewed the medical records of patients intolerant to aspirin and NSAIDs who had undergone an acetaminophen and/or celecoxib oral provocation test. Aspirin/NSAID hypersensitivity was classified into 4 types according to a recently proposed classification: aspirin-exacerbated respiratory disease (AERD), aspirin-exacerbated chronic urticaria (AECU), aspirin-induced acute urticaria/angioedema (AIAU), and NSAID-induced blended reaction (NIRD). Results A total of 180 patients with hypersensitivity to aspirin and NSAIDs were enrolled; 149 acetaminophen provocation test results and 145 celecoxib provocation test results were analyzed. The overall cross-reaction rates to acetaminophen and celecoxib were 24.8% and 10.3%, respectively. There was a significant difference in the cross-reactivity to acetaminophen according to the type of NSAID hypersensitivity. Cross-reactivity to acetaminophen was highest in the AECU group (43.9%), followed by the AERD (33.3%), NIBR (16.7%), and AIAU (12.5%) groups. Underlying chronic urticaria was more prevalent in patients with cross-intolerance to both acetaminophen (P=0.001) and celecoxib (P=0.033). Intolerance to acetaminophen was associated with intolerance to celecoxib (P<0.001). Conclusions Acetaminophen and celecoxib may induce adverse reactions in a non-negligible portion of aspirin/NSAID-sensitive patients. Physicians should be aware of the possible cross-reactions of these alternative drugs and consider an oral challenge test to confirm their tolerability.

Mechanical analysis for crack-free release of chemical-vapor-deposited diamond wafers

Chemical-vapor-deposited (CVD) diamond thick films for electronic applications must be released without cracks from the substrate as freestanding wafers. In this study, the mechanism of cracking in the CVD films was investigated experimentally and theoretically. Experimental observations showed that cracks initiated at the edge of the diamond wafer and then propagated towards the center. Finite-element analysis (FEA) reveals that, during cooling, compressive thermal stresses concentrate at the thick films edge and additional tensile stress acts circumferentially. This was verified by the experimental analysis of diamond films deposited on Si, Mo and W substrates. Observations on low interfacial adhesion and crack-free film on the W substrate indicated that, in addition to the high thermal stress, low interfacial adhesion plays an important role in cracking. Thus, film cracking depends on the fracture strength of the film and its relative magnitude with respect to interfacial adhesion. Methods of crack suppression were suggested on the basis of this cracking mechanism: increase of film thickness and minimization of the substrates CTE and interfacial adhesion. The analysis was confirmed by successful suppression of cracking by application of a low-adhesion interlayer prior to deposition of diamond film.

Skin tests in patients with hypersensitivity reaction to iodinated contrast media: a meta‐analysis

Patients with a previous history of hypersensitivity reaction (HSR) to iodinated contrast media (ICM) are at high risk of the development of HSR to ICM. Many studies have tried to evaluate the diagnostic potential of skin tests in this population but have not yet reached a common conclusion. We investigated the role of skin tests in patients with HSR to ICM in terms of positive rate, cross‐reactivity rate, and tolerability to skin test‐negative ICM according to the type of HSR.

Influence of chronic sinusitis and nasal polyp on the lower airway of subjects without lower airway diseases.

Purpose Upper and lower respiratory tract pathologies are believed to be interrelated; however, the impact of upper airway inflammation on lung function in subjects without lung disease has not been evaluated. This study investigated the association of CT finding suggesting chronic sinusitis and lung function in healthy subjects without lung disease. Methods This was a retrospective study of prospectively collected data from 284 subjects who underwent a pulmonary function test, bronchial provocation test, rhinoscopy, and osteomeatal unit computed tomography offered as a private health check-up option. Results CT findings showed that the sinusitis group had a significantly lower FEV1/FVC ratio than subjects without sinusitis finding (78.62% vs 84.19%, P=0.019). Among the sinusitis group, subjects classified by CT findings as the extensive disease group had a slightly lower FEV1/FVC than those of the limited disease group (76.6% vs 79.5%, P=0.014) and the associations were independent of the presence of airway hyperresponsiveness. The subjects with nasal polyp had also lower FEV1 and FEV1/FVC than subjects without nasal polyp (FEV1: 100.0% vs 103.6%, P=0.045, FEV1/FVC: 77.4% vs 80.0%, P=0.005). Conclusions CT findings suggesting chronic sinusitis and nasal polyp were associated with subclinical lower airway flow limitation even in the absence of underlying lung disease.