Proximal hyper-intense vessel sign on initial FLAIR MRI in hyper-acute middle cerebral artery ischemic stroke: a retrospective observational study.

BACKGROUND: A hyper-intense vessel sign on fluid attenuated inversion recovery magnetic resonance imaging (FHV) represents slow blood flow in the cerebral arteries. PURPOSE: To investigate the relationship between the proximal FHV (pFHV) on initial magnetic resonance imaging (MRI) and the status of the culprit vessel (stenosis, obstruction) in hyper-acute strokes affecting the territory of the middle cerebral artery (MCA). MATERIAL AND METHODS: The study participants consisted of 105 patients presenting to the emergency department (ED) with acute MCA infarction within 4.5 h of onset of symptoms. Patients underwent brain MRI within 45 min of arrival at the ED and angiography within 2 h of arrival. Culprit vessel status and presence of a pFHV on initial MRI were investigated retrospectively. RESULTS: The pFHV was observed in 71/105 (67.6%) patients who presented with a hyper-acute MCA infarction. All patients with hyper-acute MCA infarction caused by internal carotid artery (90.6% caused by M1 occlusion, 92.9% caused by M2 occlusion) showed a pFHV on initial MRI. After logistic regression analysis, the presence of a pFHV showed significant positive correlation with large vessel occlusion (adjusted odds ratio [OR] 34.533, 95% confidence interval [CI] 9.781-121.926; P < 0.001). A pFHV was not associated with severe large vessel stenosis. CONCLUSION: A pFHV is independently representative of the acute occlusion of intervention-eligible proximal arteries within the territory of the MCA. If a patient with a hyper-acute MCA infarction shows a pFHV, aggressive flow augmentation strategies and early activation of intervention team should be warranted for best patient outcome.

Risk of transmission via medical employees and importance of routine infection-prevention policy in a nosocomial outbreak of Middle East respiratory syndrome (MERS): a descriptive analysis from a tertiary care hospital in South Korea.

BACKGROUND: In 2015, South Korea experienced an outbreak of Middle East respiratory syndrome (MERS), and our hospital experienced a nosocomial MERS infection. We performed a comprehensive analysis to identify the MERS transmission route and the ability of our routine infection-prevention policy to control this outbreak. METHODS: This is a case-cohort study of retrospectively analysed data from medical charts, closed-circuit television, personal interviews and a national database. We analysed data of people at risk of MERS transmission including 228 in the emergency department (ED) and 218 in general wards (GW). Data of personnel location and movement, personal protection equipment and hand hygiene was recorded. Transmission risk was determined as the extent of exposure to the index patient: 1) high risk: staying within 2 m; 2) intermediate risk: staying in the same room at same time; and 3) low risk: only staying in the same department without contact. RESULTS: The index patient was an old patient admitted to our hospital. 11 transmissions from the index patient were identified; 4 were infected in our hospital. Personnel in the ED exhibited higher rates of compliance with routine infection-prevention methods as observed objectively: 93% wore a surgical mask and 95.6% washed their hands. Only 1.8% of personnel were observed to wear a surgical mask in the GW. ED had a higher percentage of high-risk individuals compared with the GW (14.5% vs. 2.8%), but the attack rate was higher in the GW (16.7%; l/6) than in the ED (3%; 1/33). There were no transmissions in the intermediate- and low-risk groups in the ED. Otherwise 2 patients were infected in the GW among the low-risk group. MERS were transmitted to them indirectly by staff who cared for the index patient. CONCLUSIONS: Our study provide compelling evidence that routine infection-prevention policies can greatly reduce nosocomial transmission of MERS. Conventional isolation is established mainly from contact tracing of patients during a MERS outbreak. But it should be extended to all people treated by any medical employee who has contact with MERS patients. TRIAL REGISTRATION: NCT02605109 , date of registration: 11th November 2015.

Manikin study showed that counting inflation breaths out loud improved the speed of resuming chest compressions during two-person paediatric cardiopulmonary resuscitation.

AIM: We investigated whether counting inflation breaths out loud during cardiopulmonary resuscitation (CPR) led to an earlier resumption of chest compressions. METHODS: In this randomised controlled manikin simulation study, conducted from February 2015 to April 2015, 32 fourth-year Korean medical students, equally divided into study and control groups, performed 10 cycles of 15:2 CPR while administering inflation breaths using a bag mask. The first study participant counted the number of inflation breaths out loud, and the second study participant was told to perform chest compressions as soon as they heard their colleague say two. The control group did not count out loud. The groups were blinded to the study outcomes and put in separate rooms. RESULTS: The median chest compression interruption time was shorter in the study group than the control group (40 vs 46 seconds, p < 0.01, r = 0.70), and the median chest compression fraction (CCF) was higher (68 vs 62%, p < 0.01, r = 0.71). Other quality outcomes related chest compressions and ventilation did not differ between the groups. CONCLUSION: Counting the number of inflation breaths out loud was a simple method that improved the speed of resuming chest compressions and increased CCFs in 15:2 CPR.

A vertical two-thumb technique is superior to the two-thumb encircling technique for infant cardiopulmonary resuscitation.

AIM: The two-thumb encircling (TTE) technique often results in suboptimal cardiac compression and does not meet the requirements of current resuscitation guidelines. We compared this technique with the vertical two-thumb (VTT) technique, our novel modification of the TTE technique. METHODS: This was a prospective randomised crossover simulation study of out-of-hospital infant cardiopulmonary resuscitation (CPR). Participants who had completed a basic life support course performed 10 cycles of cardiac compressions on a manikin for each technique. RESULTS: We enrolled 36 medical doctors who had applied for a hospital internship in this study. The VTT generated significantly higher pressure than the TTE and the pressure difference ranged from 26.8 to 62.9 mmHg for each cycle, with a mean difference of 43.5 mmHg (95% CI, 37.8-49.2). The difference in pressure showed a tendency to increase with increasing cycles of cardiac compressions. The participants' heart and respiratory rate was higher with the VTT, but they said that it was easier to perform cardiac compressions with this technique. CONCLUSION: The VTT technique generated more pressure than the TTE technique in a simulated model of infant out-of-hospital CPR. It can provide an alternative compression technique for effective infant CPR, especially for the rescuers with small hands or a weak grip.

Improved Understanding of the Macrofungal Diversity of Mongolia: Species Richness, Conservation Status, and An Annotated Checklist.

In this study, we updated and revised the checklist of macrofungi, along with the distribution of phytogeographical regions and the regional conservation status in Mongolia. The checklist comprises 677 macrofungal species belonging to 284 genera and 119 families in the country. Based on previous studies, 18 species are currently invasive to Mongolia. In this checklist, only four species are endemic to Mongolia. Among the 677 species, the regional conservation status of 51 species was previously assessed as threatened in the country. Furthermore, we collected all available occurrence records from various sources. A total of 4733 occurrences of 655 species across Mongolia were analyzed for species richness based on a 0.5° × 0.5° grid cell size. We found the records to be unevenly distributed across Mongolia, where records from the northern and central parts dominate. Among these, we identified 43 grids with a high diversity of macrofungal species. Most of these grids did not reside inside by protected geographical areas.

Utility of the Pentax-AWS in performing tracheal intubation while wearing chemical, biological, radiation and nuclear personal protective equipment: a randomised crossover trial using a manikin.

INTRODUCTION: Following a chemical, biological, radiation and nuclear (CBRN) incident, prompt establishment of an advanced airway is required for patients with respiratory failure within the warm zone, while wearing personal protective equipment (PPE). Previous studies reported that intubation attempts were prolonged, and incidence of esophageal intubation was increased with conventional Macintosh laryngoscope (McL), while wearing CBRN-PPE. Pentax-AWS (AWS), a recently introduced portable video laryngoscope, was compared with the McL to test its utility for tracheal intubation while wearing CBRN-PPE. METHODS: 31 participants performed unsuited and suited intubations on an advanced life support simulator. The sequence of intubating devices and PPE wearing were randomised. Time to complete tracheal intubation (primary end point), time to see the vocal cords, overall success rate, percentage of glottic opening, dental compression and ease of intubation were measured. RESULTS: Suited intubations required significantly longer time to complete intubation than unsuited intubations, in both McL and AWS (22.2 vs 26.4 s, 14.2 vs 18.2 s, respectively). However, suited AWS intubations required shorter time to complete tracheal intubation than unsuited McL intubations (18.2 vs 22.2 s). In secondary outcomes, moreover, suited intubations using the AWS compared favourably with unsuited intubations using the McL. CONCLUSIONS: Although the CBRN-PPE adversely affected time required to complete tracheal intubation with the AWS, suited intubations using the AWS were even superior to unsuited intubations using the McL. The AWS should be a promising device to perform tracheal intubation while wearing the CBRN-PPE.

Lecanora neobarkmaniana (Lecanorales, Lecanoraceae), A New Lichen Species from South Korea.

Lecanora is one of the largest genera of lichens worldwide. These lichens can be easily seen, and are commonly found on trees and rocks. Most Korean Lecanora species belong to the Lecanora subfusca group, which has well-defined superficial thallus, red-brown apothecia, and soredia. The new species of L. neobarkmaniana grows on rocks, farinose soredia coalescing, usually covering the whole thallus, and containing atranorin and zeorin. We used internal transcribed spacer (ITS) and mitochondrial small subunit (mtSSU) sequence data to identify the phylogenetic relationship across Lecanora sequence data and found the species to form different clades. In this study, we reported some interesting findings and described the genetic relationship with other sorediate Lecanora species and the characteristics of the new species. An identification key for the Korean sorediate Lecanora species is given.

Two New Species of the Family Acarosporaceae from South Korea.

Acarosporaceae is a crustose lichen and is known as a species that has more than 50 multi-spores, and has hyaline spores. Those taxa are often found in rock and soil in mountain areas or coastal regions in Korea, and very diverse forms and species are known. However, after an overall genetic phylogenetic analysis of carbonized ascomata in 2015, species consisting only of the morphological base are newly divided, and several species of Acarosporaceae in Korea are also being discovered in this situation. As a result of analysis using internal transcribed spacer (ITS) and nuLSU gene analysis, Korean species belonged to Acarospora and Sarcogyne clade, and Acarospora classified as the Acarospora clade was mixed with the Polysporina group and the Sarcogyne clade is mixed with the Acarospora. We identified two new species (Acarospora beangnokdamensis J. S. Park & S. O. Oh, sp. nov., Sarcogyne jejuensis J. S. Park & S. O. Oh, sp. nov.) through morphological, molecular, and secondary metabolite substance and found one new record (Sarcogyne oceanica K. Knudsen & Kocourk). We have made a classification key for Acarospora and Sarcogyne in Korea and reported all information together here.

Conventional blood tests in predicting influenza A (H1N1) rapidly.

PURPOSE: Although real-time reverse transcriptase-polymerase chain reactions (rRT-PCR) are gold standard for the diagnosis of influenza A (H1N1), the results can be delayed up to several days, which is problematic during a pandemic. Because of this limitation of rRT-PCR, clinicians have often had to set a treatment plan that was solely based on clinical suspicion. We investigated the hematological and biochemical factors that are associated with rRT-PCR results, in order to help clinicians deal with acute febrile patients during influenza pandemics. METHODS: We conducted a retrospective, cross-sectional study of 465 emergency department patients who underwent both rRT-PCR and blood tests at the same time. Hematological and biochemical findings were compared between the rRT-PCR-positive group and rRT-PCR-negative group. RESULTS: Levels of leukocytes, hemoglobin, platelets, blood urea nitrogen (BUN), total bilirubin, lactate dehydrogenase, serum glucose, C-reactive protein (CRP), and procalcitonin were significantly different between the two groups in the univariate analyses. In the multivariate analyses, leukocyte counts ≤ 10.8 (× 10(9))/L [odd ratio (OR) = 8.2, sensitivity = 93.7%, NPV = 85.3%], BUN levels ≤ 7.1 µmol/L (OR = 3.0, sensitivity = 93.7%, NPV = 85.3%), and CRP levels ≤ 60 mg/L (OR = 2.4, sensitivity = 93.7%, NPV = 85.3%) were independently associated with positive rRT-PCR results. CONCLUSIONS: Leukocyte counts, BUN levels and CRP levels were important predictors of rRT-PCR-positive results for 2009 influenza A (H1N1) in adults.

Complete mitochondrial genome sequence of Pulveroboletus ravenelii (Boletales, Basidiomycota).

Pulveroboletus ravenelii, an ectomycorrhizal fungus, has long been used in traditional Chinese medicine and mushroom dyes; however, its mitogenome and phylogenetic relationship with other taxa remain unexplored. Here, we sequenced the mitochondrial genome of P. ravenelii using next-generation sequencing and found that its mitogenome, a circular DNA molecule of 43,528 bp, comprised 15 protein-coding genes, 15 transfer RNA genes, and two ribosomal RNA genes. The mitogenome had a base composition of A (37.52%), C (11.14%), G (12.21%), and T (39.13%) and a GC content of 23.35%. A phylogenetic tree was constructed to determine the phylogenetic relationship of this species with other taxa based on the mitochondrial genome sequence. This study revealed the phylogenetic positions of P. ravenelii and its related genera for the first time.

Clinical study on ureteritis observed in contrast-enhanced computed tomography in the emergency department.

OBJECTIVE: We aimed to investigate the causes and clinical and laboratory features of patients with ureteritis observed on intravenous contrast-enhanced abdominopelvic computed tomography (APCT) conducted in the emergency department (ED). METHODS: All APCTs conducted in the ED from November 2017 to November 2020 were investigated for the presence of ureteritis. The incidence of ureteritis, presumed cause of ureteritis, and clinical as well as laboratory features of patients with ureteritis were retrospectively analyzed. RESULTS: Ureteritis was observed in 422 out of 7,386 patients (5.7%) who underwent APCTs. The two main reasons for undergoing APCT in the ED were abdominal pain (49%) and infection focus workup (33%). The first major cause of ureteritis was urinary tract infection (UTI) (351 of 422, 83%). Most patients (85%) were febrile, but 208 (59%) exhibited no urinary symptoms such as dysuria, increased frequency, or residual urine sense. The second major cause of ureteritis was ureteral stones (42 of 422, 10%). Thirty-two of 42 patients (76%) had simple obstructive uropathy, while 24% of patients had a combined infection along with an obstruction. Other rare causes were malignancy and the spread of adjacent inflammation. CONCLUSION: Ureteritis was a common finding observed in 5.7% of patients who underwent APCTs at the ED, and most of them were secondary to UTIs and ureteral stones. UTIs can cause ureteritis even without typical symptoms or signs suggestive of UTI, and diagnosis without an APCT can be difficult. More liberal use of APCTs should be considered when the cause of fever is difficult to diagnose.

Clinical investigation on acute pyelonephritis without pyuria: a retrospective observational study.

BACKGRUOUND: The current guidelines for the diagnosis of acute pyelonephritis (APN) recommend that APN be diagnosed based on the clinical features and the presence of pyuria. However, we observed that some of the patients who are diagnosed with APN do not have characteristic clinical features or pyuria at the initial examination. We performed this study to investigate the characteristics of APN without pyuria. METHODS: A retrospective, cross-sectional study was conducted on 391 patients diagnosed with APN based on clinical and radiologic findings, between 2015 and 2019. The clinical features, laboratory results, and computed tomography (CT) findings were compared between patients with normal white blood cell (WBC) counts and those with abnormal WBC counts (WBC of 0-5/high power field [HPF] vs. >5/HPF) in urine. RESULTS: More than 50% of patients with APN had no typical urinary tract symptoms and one-third of them had no costovertebral angle (CVA) tenderness. Eighty-eight patients (22.5%) had normal WBC counts (0-5/HPF) on urine microscopy. There was a negative correlation between pyuria (WBC of >5/HPF) and previous antibiotic use (odds ratio, 0.249; 95% confidence interval, 0.140-0.441; p<0.001), and the probability of pyuria was reduced by 75.1% in patients who took antibiotics before visiting the emergency room. CONCLUSION: The diagnosis of APN should not be overlooked even if there are no typical clinical features, or urine microscopic examination is normal. If a patient has already taken antibiotics at the time of diagnosis, imaging studies such as CT should be performed more actively, regardless of the urinalysis results.

Tracheal intubation during chest compressions using Pentax-AWS(®), GlideScope (®), and Macintosh laryngoscope: a randomized crossover trial using a mannequin.

BACKGROUND: A randomized crossover trial was conducted to compare the performance of two videolaryngoscopes (Pentax-AWS(®), GlideScope(®)) with the Macintosh laryngoscope for tracheal intubation during continuous chest compressions on a mannequin. METHODS: Thirty-two inexperienced junior interns performed tracheal intubations on an advanced life support simulator with either a normal or difficult airway scenario. The sequence of intubating devices and airway difficulty were randomized. The following data were measured and recorded: time to complete tracheal intubation (primary end point), overall success rate, time to visualize the vocal cords, percentage of glottic opening, dental compression, and ease of intubation. RESULTS: With a normal airway, the times (median [interquartile range]) to complete tracheal intubation were shorter with the Pentax-AWS (12.1 [10.1-14.4] sec) and the GlideScope (14.3 [12.4-17.6] sec) than with the Macintosh laryngoscope (16.5 [13.1-22.1] sec) (P < 0.03 for both). The time difference between the two videolaryngoscopes was not statistically significant. With a difficult airway scenario, the times to complete tracheal intubation were 13.9 [10.9-20.4] sec, 19.2 [16.4-32.3] sec, and 30.1 [21.0-56.5] sec, respectively (P < 0.05 for all differences). The videolaryngoscopes were also more effective than the Macintosh laryngoscope with respect to secondary outcomes. CONCLUSIONS: The two videolaryngoscopes were superior to the Macintosh laryngoscope in terms of performing tracheal intubation during continuous chest compressions on a mannequin. In a difficult airway scenario simulating cardiac arrest, the Pentax-AWS performed better than the GlideScope.

Utility of a Modified Oropharyngeal Airway for Performing Tracheal Intubation Using a Fiberoptic Bronchoscope and Video Stylet: A Randomized Crossover Trial Using a Manikin.

PURPOSE: The purpose of this study was to assess if a modified airway (MA), developed by the authors, would act as a guide and improve the performance of intubation when used with a video stylet (VS) or fiberoptic bronchoscope (FOB) for endotracheal intubation. METHODS: This randomized crossover simulation study using manikins was conducted with 36 novice operators. Time to complete intubation, time to see the glottis, and success rate of intubation of each device were measured and compared with or without use of MA. RESULTS: For intubation using FOB with MA, the median time to complete intubation significantly reduced from 46 to 31 seconds with a medium effect size (p=0.004, r = 0.483), and the median time to see the glottis significantly reduced from 7 to 5 seconds with a medium effect size (p=0.032, r = 0.357). The overall success rate was not statistically different between FOB with MA (33/36, 91.7%) and FOB alone (31/36, 86.1%); however, the cumulative success rate over time for FOB with MA was higher than that for FOB alone (p=0.333). For intubation using VS, there were no differences in the time to see the glottis and time to complete intubation between VS with MA and VS alone (p=0.065 and p=0.926, respectively), and the cumulative success rate was not statistically significant (p=0.594). CONCLUSION: Adjunct use of MA helped reduce time to complete intubation in FOB, but not in VS. If an inexperienced operator uses FOB, it would be helpful to use MA as an adjunct device.

Chronic Gastritis Is Associated with a Decreased High-Density Lipid Level: Histological Features of Gastritis Based on the Updated Sydney System.

Chronic gastritis could activate a systemic inflammatory response that could result in adverse lipid profiles. To determine the severity of chronic gastritis, Helicobacter pylori (HP), mononuclear cell (lymphocytes and plasma cells), and neutrophil scores were assessed on the basis of the updated Sydney system (USS), which is widely used for histological grading. The aim of this study was to assess the relationships between gastric histological features and lipid profile levels. This study included 15,322 males and 5929 females who underwent a health checkup and gastric biopsy at the Kangbuk Samsung Medical Center (KBSMC). We analyzed whether the HP, mononuclear cell, and neutrophil grades according to the USS were related to serum leukocyte count, unhealthy behaviors, and lipid profile levels. Gastritis with HP, neutrophils, or moderate to severe mononuclear cells was associated with an elevated serum leukocyte count. A high leukocyte count was related to increased low-density lipoproteins (LDL) and triglycerides/very-low-density lipoprotein (VLDL) and decreased high-density lipoproteins (HDL). In multivariate analyses, chronic gastritis with HP or moderate to severe mononuclear cells was significantly associated with decreased HDL in males, while mononuclear cells were significantly related to decreased HDL in females. Chronic gastritis was associated with an increased systemic inflammatory response, which was associated with unfavorable lipid profiles, especially low HDL levels.

Current Guideline of Chest Compression Depth for Children of All Ages May Be Too Deep for Younger Children.

AIM: To determine whether the chest compression depth of at least 1/3 of the Anteroposterior (AP) diameter of the chest and about 5 cm is appropriate for children of all age groups via chest computed tomography. METHODS: The AP diameter of the chest, anterior chest wall diameter, and compressible diameter (Cd) were measured at the lower half of the sternum for patients aged 1-18 years using chest computed tomography. The mean ratio of 5 cm compression to the Cd of adult patients was used as the lower limit, and the mean ratio of 6 cm compression to the Cd of adult patients was used as the upper limit. Also, the depth of chest compression resulting in a residual depth <1 cm was considered to cause internal injury potentially. With the upper and lower limits, the compression ratios to the Cd were compared when compressions were performed at a depth of 1/3 the AP diameter of the chest and 5 cm for patients aged 1-18 years. RESULTS: Among children aged 1-7 years, compressing 5 cm was deeper than 1/3 the AP diameter. Also, among children aged 1-5 years, 5 cm did not leave a residual depth of 1 cm, potentially causing intrathoracic injury. CONCLUSION: Current pediatric resuscitation guidelines of chest compression depth for children were too deep for younger children aged 1-7 years.

Arthonia dokdoensis and Rufoplaca toktoana - Two New Taxa from Dokdo Islands (South Korea).

Arthonia dokdoensis sp. nov., a lichenicolous fungus from the subcosmopolitan Arthonia molendoi complex growing on crustose thalli of species of the genus Orientophila (subfamily Xanthorioideae, Teloschistaceae), as well as the lichen species Rufoplaca toktoana sp. nov. (subfamily Caloplacoideae, Teloschistaceae) similar to Rufoplaca kaernefeltiana, both from Dokdo Islands, Republic of Korea, are described, illustrated, and compared with closely related taxa. In the phylogenetic tree of the Arthoniaceae based on 12S mtSSU and RPB2 gene sequences, the phylogenetic position of the A. dokdoensis and the relationship with the A. molendoi group are illustrated, while the position of the newly described R. toktoana is confirmed by phylogenetic tree based on ITS nrDNA data.

Macrofungal Survey of the Tian Shan Mountains, Kyrgyzstan.

The Tian Shan mountain system is one of the large mountain ranges located in Central Asia. This region is globally recognized as mountain ranges, offering inestimable wealth in fauna and flora with significant biodiversity values. We surveyed macrofungal diversity of Tian Shan in Kyrgyzstan from 2016 to 2018. A collection of macrofungi was made, and these were subjected to sequence comparisons and phylogenetic analysis to ensure the identity of the collected macrofungi. Of those collected, 95 out of 100 specimens were successfully sequenced and compared with those of other related species retrieved from GenBank. The sequenced specimens were classified into 2 phyla, 8 orders, 24 families, 47 genera, and 57 species, based on current taxonomic concepts (combining morphology and phylogeny). To the best of our knowledge, this study provides the first well-documented checklist and phylogenetic analysis of macrofungi recovered from the Tian Shan mountains in Kyrgyzstan.

First Report of Buchwaldoboletus lignicola (Boletaceae), a Potentially Endangered Basidiomycete Species, in South Korea.

During the 2014 survey of the mushroom flora of Gwangneung forest in South Korea, we collected two specimens of boletoid mushroom growing on a felled tree of Pinus koraiensis. These specimens were characterized by a light brown to reddish-brown pileus with appressed tomentum, pore surface bluing instantly when bruised, golden-yellow mycelium at the base of stipe, and lignicolous habitat. Both specimens were identified as Buchwaldoboletus lignicola, a rare basidiomycete, based on morphological characteristics and sequences of internal transcribed spacer (ITS; fungal barcode). Here, we describe these specimens and provide the first report of this genus in South Korea.

Characteristics of blood tests in patients with acute cerebral infarction who developed symptomatic intracranial hemorrhage after intravenous administration of recombinant tissue plasminogen activator.

OBJECTIVE: Patients suspected as having acute ischemic stroke usually undergo blood tests, including coagulation-related indexes, because thrombocytopenia and coagulopathy are contraindications for recombinant tissue plasminogen activator (rtPA) administration. We aimed to identify blood test indexes associated with symptomatic intracranial hemorrhage (sICH) in patients with acute ischemic stroke who received intravenous rtPA. METHODS: This retrospective observational study included patients diagnosed with acute ischemic stroke who were treated with intravenous rtPA at the emergency department of a tertiary hospital in Seoul between February 2008 and January 2018. Blood test indexes were compared between the sICH and non-sICH groups. Logistic regression and receiver-operating characteristic curve analyses were performed. RESULTS: In this study, 375 patients were finally included. Of 375 patients, 42 (11.2%) showed new intracranial hemorrhage on follow-up brain computed tomography, of whom 14 (3.73%) had sICH. Platelet count, aspartate aminotransferase and lactate dehydrogenase levels were significantly different between the sICH and non-sICH groups, and platelet count showed statistical significance in the regression analysis. Significantly lower platelet counts were observed in the sICH group than in the non-sICH group (174,500 vs. 228,000/mm3, P=0.020). The best cutoff platelet count was 195,000/mm3, and patients with platelet counts of <195,000/mm3 had a 5.4- times higher risk of developing sICH than those with platelet counts of ≥195,000/mm3. CONCLUSION: Platelet count was the only independent parameter associated with sICH among the blood test indexes. Mild thrombocytopenia may increase the risk of sICH after intravenous administration of rtPA.