Dissemination of an international high-risk clone of Escherichia coli ST410 co-producing NDM-5 and OXA-181 carbapenemases in Seoul, Republic of Korea

The rapid increase in carbapenemase-producing Enterobacterales is a global health concern. During 2017-2020, a total of 44 Escherichia coli isolates co-harbouring bla_NDM-5 and bla_OXA-181 were collected from patients at 17 hospitals in Seoul and characterized based on antimicrobial susceptibility, resistance genes and plasmid replicons detected using polymerase chain reaction (PCR). Clonal relatedness was estimated using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). All isolates had an identical multidrug resistance profile, including resistance to carbapenems, cephalosporins, ciprofloxacin, tetracycline, and trimethoprim/sulfamethoxazole, and susceptibility to amikacin, colistin, and tigecycline. Resistance genes (bla_CTX-M-15, bla_CMY-2, bla_TEM-1B, bla_OXA-1, aac(6')-Ib-cr, and qnrS) and plasmid replicons (IncFIA, IncFIB, and IncX3) was observed in almost all isolates. All isolates belonged to ST410 and were genetically similar (>88% similarity), with some PFGE types shared among isolates from different hospitals. Analysis of the whole genome revealed that the isolates clustered together with other strains of the international high-risk clone ST410 B4/H24RxC from other countries. These findings underline the ongoing spread of the high-risk clone of NDM-5- and OXA-181-producing E. coli ST410 B4/H24RxC among hospitals in Seoul. Continuous monitoring and implementation of infection control measures are crucial to track and prevent further spread of these resistant strains.

Distribution of mcr genes among carbapenem-resistant Enterobacterales clinical isolates: High prevalence of mcr-positive Enterobacter cloacae complex in Seoul, Republic of Korea

Colistin is usually used as a drug of last resort against infections caused by multidrug-resistant gram-negative bacteria, including carbapenem-resistant Enterobacterales (CRE). Recently, the acquisition of mobile colistin resistance (mcr) genes by CRE is a cause for worry. Here, we investigated the prevalence of mcr genes in CRE isolates in Seoul, Korea. A total of 3,675 CRE strains were collected from patients between 2018 and 2019 and initially screened for mcr genes using multiplex-PCR assays. Upon the identification of mcr-harboring strains, colistin susceptibility tests, identification of carbapenemase and β-lactamase genes, and plasmid replicon typing were performed. Clonal analysis was conducted using pulsed-field gel electrophoresis. mcr genes were detected in 2.2% (80/3,675) CRE strains. There were three mcr-1, one mcr-4.3, one mcr-4.3/mcr-9, 58 mcr-9, one mcr-9/mcr-10, and 16 mcr-10 carriers from various Enterobacterales species, of which 60 were in Enterobacter cloacae complex (ECC) strains. The mcr prevalence in ECC was 20.5%. Molecular detection confirmed that 21.3% and 13.8% of the mcr-harboring strains shared bla_NDM-1 or bla_KPC-2, respectively. In addition, an IncHI2 replicon was identified in 71.7% of the mcr-9 strains. Comparative analysis revealed not only a notable diversity of mcr carriers, but also clonal spreading or nosocomial outbreak of some ECC strains. Our findings revealed a silent distribution of mcr in CRE strains with high genetic heterogeneity in Seoul, underscoring the urgent need for timely intervention to control and prevent mcr dissemination.

Emergence of a multidrug-resistant clinical isolate of Escherichia coli ST8499 strain producing NDM-13 carbapenemase in the Republic of Korea

We described a carbapenem-resistant Escherichia coli ST8499 strain producing New Delhi metallo-β-lactamase-13 (NDM-13) from patient in Korea. The isolate exhibited multidrug resistance, but remained susceptible to colistin and tigecycline. The bla_NDM-13 gene was located on a 130-kb self-transmissible plasmid. This is the first report of NDM-13 carbapenemase in Korea.

Metronome vs. Popular Song: A Comparison of Long-Term Retention of Chest Compression Skills after Layperson Training for Cardiopulmonary Resuscitation

Introduction

Long-term retention of cardiopulmonary resuscitation (CPR) skill is challenging for layperson trainees. This study compared the long-term retention of chest compression skills after either metronome-guided (MG) or popular song-guided (PG) CPR training.

Methods

This was a prospective randomised simulation trial. Untrained laypersons were randomly allocated to MG (n=61) or PG (n=68) groups at CPR training sessions. After CPR training, each participant performed 5-cycle CPR using a manikin with a Skill-Reporter™ immediately and six months afterwards.

Results

Immediately after training, the mean compression rate (MCR) was slightly higher in the PG than the MG group (107.4 vs. 102.2/min; p<0.0001), but there was no significant difference in the proportions of participants with an appropriate chest compression rate (100-120/min) (PSACCR) between the MG and PG (53/61 (86.9%) vs. 65/68 (95.6%); p=0.114). Six months later, MCR was faster in the MG than the PG (124.8 vs. 110.0/min; p<0.0001), and PSACCR in the PG was higher than that in the MG (62/68 (91.2%) vs. 25/61 (41.0%); p<0.0001). In both tests, there were no significant differences in other chest compression parameters of between the two groups, except for a minimal difference in incomplete chest release.

Conclusion

CPR training using a popular song is more effective than metronome-guided training in helping laypersons to maintain recommended compression rates after 6 months. (Hong Kong j.emerg.med. 2016;23:145-152)

The clinical significance of infrared thermography for the prediction of postherpetic neuralgia in acute herpes zoster patients

BACKGROUND

Infrared thermography is a non-invasive diagnostic tool that provides information for damage to the nerve, there was some reports that thermal asymmetry of acute Herpes zoster (HZ) patients was significantly related to development of PHN.

OBJECTIVE

To identify whether infrared thermography is useful as a predictor for the development of postherpetic neuralgia (PHN) and as an objective assessment tool of subjective pain in acute HZ patients.

METHODS

Infrared thermography was performed on the affected body regions of 112 patients who had been diagnosed with an acute stage of HZ. Demographic and clinical data were recorded. Differences >0.5°C for the mean temperature across the face and trunk were considered abnormal. According to whether PHN developed or not, we analyzed the correlation of risk factors.

RESULTS

The study consisted of a total of 112 subjects (46 males and 66 females) with an age range of 9-93 years. The following summarizes the analysis results. (1) As pain severity increased, the occurrence of PHN increased significantly. (2) In older patients, the occurrence of PHN was significantly higher. (3) As the temperature difference between the affected and contralateral dermatome (ΔT) increased, the occurrence of PHN increased significantly. (4) There is a statically significant association between diabetes mellitus and the occurrence of PHN. (5) There is no correlation between pain intensity and ΔT.

CONCLUSION

In this study, we showed that infrared thermography is useful as a predictor of PHN development in acute HZ patients but is not useful as an objective assessment tool for indicating subjective pain.

Efficacy and safety of topical glycopyrrolate in patients with facial hyperhidrosis: a randomized, multicentre, double-blinded, placebo-controlled, split-face study

BACKGROUND

Although facial hyperhidrosis has been frequently associated with a diminished quality of life, various conservative modalities for its management are still far from satisfactory.

OBJECTIVE

To evaluate the antiperspirant efficacy and safety of the topical glycopyrrolate on facial hyperhidrosis at specified posttreatment intervals.

METHODS

Thirty-nine patients with facial hyperhidrosis were enrolled and treated with 2% topical glycopyrrolate on one-half of the forehead, whereas the other half of the forehead was treated with a placebo. All patients applied topical glycopyrrolate or placebo once a day for nine successive days. Each evaluation included weighing sweat and assessing the Hyperhidrosis Disease Severity Scale (HDSS) score and any adverse effects.

RESULTS

Compared with the placebo-treated sides, topical glycopyrrolate-treated sides showed a reduction in the rate of sweat production at the forehead of 25.16 ± 10.30% (mean ± SD) at 90 min after the first application (day 1), 29.63 ± 7.74% at 24 h after the first application (day 2) and 36.68 ± 11.41% at 24 h after eight additional successive daily applications (day 10) (all P < 0.025). There was a little more decrease in HDSS score with the topical glycopyrrolate-treated half of the forehead, but the difference was not statistically significant (P > 0.025). No serious adverse events were reported during the course of this study. Only one patient developed a transient headache after treatment.

CONCLUSION

Topical glycopyrrolate application appears to be significantly effective and safe in reducing excessive facial perspiration.

Monitoring and risk assessment of pesticide residues in commercially dried vegetables

We tested for residual pesticide levels in dried vegetables in Seoul, Korea. A total of 100 samples of 13 different types of agricultural products were analyzed by a gas chromatography-nitrogen phosphate detector (GC-NPD), an electron capture detector (GC-μECD), a mass spectrometry detector (GC-MSD), and a high performance liquid chromatography-ultraviolet detector (HPLC-UV). We used multi-analysis methods to analyze for 253 different pesticide types. Among the selected agricultural products, residual pesticides were detected in 11 samples, of which 2 samples (2.0%) exceeded the Korea Maximum Residue limits (MRLs). We detected pesticide residue in 6 of 9 analyzed dried pepper leaves and 1 sample exceeded the Korea MRLs. Data obtained were then used for estimating the potential health risks associated with the exposures to these pesticides. The estimated daily intakes (EDIs) range from 0.1% of the acceptable daily intake (ADI) for bifenthrin to 8.4% of the ADI for cadusafos. The most critical commodity is cadusafos in chwinamul, contributing 8.4% to the hazard index (HI). This results show that the detected pesticides could not be considered a serious public health problem. Nevertheless, an investigation into continuous monitoring is recommended.

Evaluation of Chest Compression Depth during Nine Minutes of Hands-Only Cardiopulmonary Resuscitation Performed by a Lone Rescuer and its Effect by Age Group: A Pilot Simulation Study Using a Manikin

Objective

There have been few studies on the use of long-standing hands-only cardiopulmonary resuscitation (CPR) by a lone rescuer. This study aimed to evaluate the long-standing (nine minutes) hands-only CPR by a lone rescuer, and the change of chest compression depth over time. The effect of age of rescuer on chest compression depth was also studied.

Methods

From a total of 404 adult lay-persons who participated in CPR training, 91 subjects were enrolled in the simulation trial of nine minutes of hands-only CPR using a manikin with a Skill-Reporter™. The quality of the chest compression over time and the effects of rescuer age were analysed.

Results

Of the 91 participants, 74 (81%) fully completed the nine minutes of CPR. No significant differences of incomplete CPR rate between each age group were observed. No significant differences in the degree of reduction in effective chest compressions were observed based on the time course among the different age groups. The total number of compressions decreased abruptly from the six-minute time point onwards (five minutes vs. six minutes, p=0.038).

Conclusions

Most trained lay-persons could complete the 9 minutes of hands-only CPR. The rate of chest compression shows a significant decrease after 6 minute. We do not find a significant difference in the decrease of adequate chest compressions over time among various age groups in this pilot simulation study.

Photodynamic therapy: new treatment for refractory lymphocytic infiltration of the skin

Lymphocytic infiltration of the skin (LIS) is a relatively uncommon skin condition, first described by Jessner and Kanof in 1953. LIS presents mainly on the face, in particular on the cheeks and earlobe, but also on the neck, upper trunk or proximal limbs of middle-aged adults. LIS is often resistant to treatment. Photodynamic therapy (PDT) refers to the process of applying a topical prodrug, such as 5-aminolaevulinic acid (ALA) or methyl 5-aminolaevulinic acid (MAL), followed by irradiation with visible or ultraviolet light. The prodrug is converted by target tissue to photoactive porphyrins, which lead to local tissue destruction when activated by light. We describe a 48-year-old woman with refractory LIS, who was treated with MAL-PDT.

Management of anterior inferior cerebellar artery aneurysms: endovascular treatment and clinical outcome

BACKGROUND AND PURPOSE

AICA aneurysms are rare and a challenge to treat surgically. We present our experience of the angiographic results and the clinical outcomes for 9 AICA aneurysms treated by EVT.

MATERIALS AND METHODS

Between 1997 and 2009, EVT was attempted for 9 AICA aneurysms. Six patients presented with SAH, and 3 aneurysms were found incidentally. The location of the aneurysms was the proximal AICA in 7 and the distal AICA in 2. Five aneurysms originated from an AICA-PICA variant. Clinical outcomes and procedural complications were evaluated, and angiography was performed 6, 12, and 24 months after embolization to confirm recanalization of the coiled aneurysm.

RESULTS

EVT was technically successful in 7 patients (78%). Surgical trapping was performed in 1 patient after failure of EVT, and another aneurysm occluded spontaneously, along with the parent artery during EVT. In 7 patients, the AICAs had good patency on postoperative angiography. Stent-assisted coiling was performed in 3 patients. Follow-up angiographies were performed in 7 patients and showed no evidence of recanalization or progressive occlusion with further thrombosis except in 1 patient. There was no evidence of aneurysm rupture during the follow-up period, and 8 patients were able to perform all usual activities (mRS score, 0-1).

CONCLUSIONS

EVT may provide a feasible and safe option as an alternative, though a microsurgical option is initially considered for the management of AICA aneurysms. Further follow-up and more experience are also necessary.

Reconstructive endovascular treatment of intracranial fusiform aneurysms: a 1-stage procedure with stent and balloon

BACKGROUND AND PURPOSE

Intracranial fusiform aneurysms, which incorporate the branch vessel and require salvaging of the parent vessel, are difficult to manage. The goal of this study was to evaluate the efficacy of reconstructive endovascular treatment of intracranial fusiform aneurysms by using a 1-stage procedure with a stent and balloon.

MATERIALS AND METHODS

During a 3-year period, 20 patients with 20 intracranial fusiform aneurysms were treated by using a 1-stage procedure involving a balloon and stent. Subarachnoid hemorrhage was present in 15 patients. Five aneurysms were located in the anterior circulation and 15, in the posterior circulation. Clinical outcomes and periprocedural complications were evaluated in all patients. The extent of coil packing was evaluated by control angiography after embolization and classified as either complete occlusion or partial occlusion. Angiography was performed 6, 12, and 24 months after embolization to evaluate stent patency and coil packing.

RESULTS

The 1-stage procedure by using a combination of balloon and stent was technically successful in all patients. There were no complications related to the procedure, complete occlusion was obtained in 16 patients, and partial occlusion, in 4 patients. All patients recovered well except for 2 who died due to causes unrelated to the procedure. Clinical follow-up was performed in all surviving patients at a mean of 12.3 months (range, 7-24 months), and angiography showed that the patent parent arteries were free of aneurysm recanalization or in-stent stenosis.

CONCLUSIONS

This 1-stage procedure may provide a feasible and safe treatment strategy for the management of intracranial fusiform aneurysms that are not amenable to deconstructive embolization.

Effect of a new infrared light device (1100-1800 nm) on facial lifting

Laser skin resurfacing procedures can be classed into two categories - invasive and non-invasive. The last several decades have witnessed a host of advancements in ablative laser therapy and other ablative modalities for the rejuvenation of skin, including the CO(2) laser, the erbium : yttrium aluminum garnet laser, chemical peels, and dermabrasion. Despite the excellent results that can result from the practice of these techniques by experienced surgeons, the invasive nature of these devices is associated with inherent risks and patient discomfort. Therefore, much of the focus has been on non-ablative lasers and intense-pulsed light devices. We evaluated the efficacy and safety of treatment with the new infrared light device (1100-1800 nm), Titan, and assessed the degree of improvement associated with two-time laser treatments, as compared to one-time laser treatment.

Endovascular treatment of intracranial vertebral artery dissections with stent placement or stent-assisted coiling

BACKGROUND AND PURPOSE

Endovascular treatment with stent placement or stent-assisted coiling was recently introduced as an alternative to parent artery occlusion in intracranial vertebral artery dissections. We describe the efficacy and limitations of this method.

METHODS

Fourteen patients with intracranial vertebral artery dissection were treated with stent placement (10 patients) or stent-assisted coiling (4 patients). Double overlapping stents were deployed in 4 of 10 patients with stent placement alone. Angiographic follow-up at 6 to 12 months was available in 13 patients.

RESULTS

In 13 patients with dissecting aneurysm, immediate angiographic outcomes were complete occlusion (1 patient), nearly complete (2 patients), and incomplete (10 patients). Follow-up angiograms of 12 of these patients showed complete occlusion (6 patients) and incomplete (6 patients; 1 unstable and 5 stable). Complete occlusion rates in follow-up angiograms were superior in double stent placement (75%) or stent-assisted Guglielmi detachable coil (GDC) embolization to stent placement alone (0%). There were no instances of postprocedural ischemic attacks, new neurologic deficits, and no new minor or major strokes before patient discharge. On the modified Rankin scale applied in follow-up, all patients were assessed as functionally improved or of stable clinical status.

CONCLUSIONS

Intracranial vertebral artery dissections were acceptably treated with stent placement or stent-assisted coiling, and the patency could be preserved at follow-up. However, the efficiency of stent placement alone for intracranial vertebral artery dissecting aneurysm was limited. Stent-assisted coil embolization or double stent placements are a viable alternative for complete occlusion of dissecting aneurysms.

The effect of amniotic membrane extract on the expression of iNOS mRNA and generation of NO in HaCaT cell by ultraviolet B irradiation

BACKGROUND/PURPOSE

Amniotic membrane (AM) is the innermost fetal membrane, which contains several proteinase inhibitors and expresses several growth factors. Nitric oxide (NO) has been implicated in the pathogenesis of various inflammatory diseases including sunburn and ultraviolet induced erythema. The expression of inducible nitric oxide synthase (iNOS) is up regulated by UVB irradiation and inhibited by TGF-beta and EGF-beta. We evaluated the effect of AM extract on the expression of iNOS mRNA by UV irradiation in HaCaT cell (immortalized human keratinocyte cell line).

METHODS

HaCaT cells were irradiated UVB 30 mJ/cm2 and AM extract was added. The iNOS mRNA was isolated by RT-PCR and NO production was assessed by spectrophotometric method based on Griess reaction.

RESULTS

The expression of iNOS mRNA was induced by UVB irradiation in HaCaT cell and the expression of iNOS mRNA was higher at 48 h than that at 24 h. AM extract down regulated the induction of iNOS mRNA in HaCaT cell by UVB irradiation. NO generation was increased by UVB irradiation, but down regulated by AM extract treatment in HaCaT cells.

CONCLUSION

These results assured that the expression of iNOS mRNA and generation of NO are up regulated by UVB irradiation and showed that AM extract down regulated the induction of iNOS mRNA and decreased generation of NO by UVB irradiation.

Time course of expression of mRNA of inducible nitric oxide synthase and generation of nitric oxide by ultraviolet B in keratinocyte cell lines

BACKGROUND

Nitric oxide (NO), the ubiquitous free radical, has been implicated in the pathogenesis of various inflammatory diseases, including sunburn and ultraviolet (UV) radiation-induced pigmentation, and it also seems to play an important part in host defence against bacterial infection.

OBJECTIVES

The purpose of this study was to determine the time course of production of NO and time course of expression of inducible NO synthase (iNOS) by UVB irradiation and lipopolysaccharide (LPS) stimulation in keratinocyte cell lines. Furthermore, we intended to elucidate the relationship between iNOS and NO in various stimulated conditions.

METHODS

Normal human keratinocytes (NHK), HaCaT cells and PAM212 cells were irradiated with UVB at a dose of 50 mJ cm-2 and 100 mJ cm-2. Separately, the cell lines were stimulated with 20 micro g of LPS. NO was measured by the Griess assay and iNOS mRNA was isolated by reverse transcriptase-polymerase chain reaction at 12, 24, 48 and 72 h after stimulation.

RESULTS

The generation of NO was induced by UVB irradiation and LPS stimulation. NO production was significantly increased at 72 h after irradiation of UVB 100 mJ cm-2 in NHK, and at 48 and 72 h in HaCaT cells. In PAM212 cells, NO production was significantly increased at 12, 24, 48 and 72 h by UVB 100 mJ cm-2 and at 72 h by LPS. Induction of iNOS mRNA peaked at 48 h and then decreased to basal level at 72 h when treated with UVB irradiation. The time course of production of NO was approximately correlated with the timing of induction of iNOS mRNA.

CONCLUSIONS

These results suggest that the expression of iNOS mRNA is upregulated by UVB irradiation, and that NO produced by this inducible enzyme may play a part as a mediator or an immunomodulator in UV-induced skin reactions such as sunburn reaction and photo-induced immune alterations.

Expressions of beta-defensins in human keratinocyte cell lines

BACKGROUND

Defensins, a major family of antimicrobial peptides, are small cationic, cysteine-rich peptides with a wide range of antimicrobial activity. In human, beta-defensin-1 was isolated from urine and cervical mucous suggesting that this peptide plays an antimicrobial role in the genitourinary tract. Beta-defensin-2 was identified in psoriatic scale produced by keratinocytes suggesting that this peptide contributes to defend the expansive surface of the integuments.

OBJECTIVE

Current research was done to investigate the expression and modulation of beta-defensin mRNA in human keratinocyte cell lines.

METHODS

HaCaT and A431 cell lines were used to all culture experiments. Cultured human keratinocytes were stimulated with ultraviolet (UV) B irradiation or tumor necrosis factor-alpha (TNF-alpha) or lipopolysaccharide (LPS) to determine whether defensin mRNA production occurred. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to amplify defesin cDNA from stimulated keratinocytes, and southern blots were used to verify the specificity of RT-PCR amplication products.

RESULTS

Expression of human beta-defensins was upregulated with UVB irradiation, TNF-alpha and LPS in HaCaT cells and in comparison to the control, significantly higher at 6 h post stimulation with UVB 100 mJ/cm2 and peak at 12 to 18 h post stimulation with UVB 30 mJ/cm2, TNF-alpha and LPS. A431 cells did not show expression of human beta-defensins in unstimulated state, even after irradiation with UVB or TNF-alpha or LPS.

CONCLUSIONS

This report demonstrates the presence of defensin in human keratinocytes and capacity of human keratinocytes to produce defensin mRNA in response to UVB irradiation, TNF-alpha and LPS. Release of defensins by keratinocytes in response to cytokines elaborated in inflammation may contribute to the host defense responses.

Hair restoration surgery in patients with hypotrichosis of the pubis: the reason and ideas for design

BACKGROUND

Hypotrichosis of the pubis is not an uncommon condition, especially in oriental women. Besides the aesthetic problem, this condition may cause low self-esteem, social embarrassment, and psychologic problems to patients. There have been many efforts to correct this condition medically and surgically for decades. Among them hair restoration surgery is thought to be the only definitive therapeutic modality at present.

OBJECTIVE

Our purpose was to show the importance of preoperative evaluation of what type of pubic hair patterns the patients may seek and thereafter to make a design based on the patients' desire and physiologic feature of pubic hair for the natural-appearing results and satisfaction of the patients.

METHODS

Ten female patients were enrolled in this study aged between 23 and 48 years with pubic hair maturity index class I-III. For selection of a patients' favored pubic hair pattern, we provided photograph samples of pubic hair patterns that consisted of four types as previously documented: horizontal, sagittal, acuminate, and disperse. We restored hairless mons using a conventional one- to three-haired mini-micrograft technique.

RESULTS

Five patients belonged to the pubic hair maturity index class I, four to class II, and one to class III. Seven of 10 patients wanted a horizontal (inverted triangular) type, which is most commonly seen in young females, 2 patients wanted acuminate, and 1 wanted sagittal. Eight patients underwent a single-session operation, while two others underwent operations twice. The two patients requiring two operation sessions belonged to a group of class I pubic hair and desired acuminate-type hair. Most patients were satisfied with the results of their operations.

CONCLUSION

In designing a pubic hair graft, it is important to know the patients' desire and to make a design based on it for the satisfaction of the patients and for natural-appearing results. Before the procedure, dermatologic surgeons should have to consider a grafted hair line, the distribution, density, and directions of the hair shaft, and the angling of the hair to the skin.

Least-squares fitting of the phase map obtained in phase-shifting electronic speckle pattern interferometry

A new method has been developed to remove noise from the deformation phase map obtained by a phase-shifting electronic speckle pattern interferometry. Unlike usual methods, it estimates almost noise-free phase values directly from the distributions of the intensity differences of four interference patterns by a least-squares fit. The fluctuations of uniform deformation phases are reduced to less than 0.05 rad with a 5 x 5 pixel fitting window. The so-called sawtooth phase jumps that are due to the use of arctangent functions are retained sharply in this method.

Comparison of albuterol to isoproterenol as a bronchodilator for use in pulmonary function testing

We compared the effectiveness of albuterol with isoproterenol as a bronchodilator for use in pulmonary function testing. A total of 180 patients presenting for routine pulmonary function testing were randomly assigned to receive 5 mg of either albuterol or isoproterenol by compressed air nebulizer. Forced expiratory maneuvers were performed before, 5 min after, and 10 min after bronchodilator administration. The average increase in FEV1 and FVC did not differ between drugs. Also, the fraction of patients achieving a clinically significant bronchodilator response did not differ between drugs. Importantly, there was no significant difference between average 5 and 10 min postbronchodilator values for FEV1 or FVC for either bronchodilator, suggesting that a peak response was reached by 5 min. These results show no advantage of isoproterenol over albuterol in terms of potency or speed of action. Given the well-known cardiovascular side effects of isoproterenol, albuterol is the preferable agent for use in pulmonary function testing.