Simultaneous Nosocomial SARS-CoV-2 Outbreaks with Different Patterns of Occurrence in Two General Wards; Experience in a Tertiary Care Hospital in Korea

A nosocomial outbreak of severe acute respiratory syndrome-coronavirus-2 occurred in two general wards. One outbreak had pre-symptomatic transmission and was linked epidemiologically with an index case. The other outbreak was associated with early detection failure in a crowded room. Notably, adherence to appropriate mask wearing was not confirmed in the hospital outbreak. Confirmed cases were moved into isolation rooms, and contacts were quarantined. Quarantined cases were tested regularly and facilitated early termination of the hospital outbreak.

A study of factors influencing the length of stay in the emergency department of patients who were admitted after a self-poisoning suicidal attempt

Objective@#A suicide attempt by self-poisoning is a common cause of admissions to the emergency department (ED). Management of such intentiona poisoning often requires complicated medical procedures, resulting in a longer length of stay (LOS) as compared to other cases that require treatment in the ED. This study aimed to determine the factors affecting a longer LOS in self-poisoning patients. @*Methods@#This was a retrospective study wherein all the medical charts of patients who visited the ED of one hospital, from August 2016 to July 2019, because of intentional self-poisoning, were reviewed. @*Results@#Most of the patients visited the ED involuntarily and there were almost twice as many female patients as males. Almost half of the patients were referred to the psychiatry department. A comparison of various factors within the LOS groups revealed significant differences in mental status, guardian co-visitation, patient gender, psychiatric referral, and poisoning substance. Moreover, the LOS had a stronger association with the pre-consultation period than the consultation to decision-making period. @*Conclusion@#To reduce the LOS, it seems important to make a rapid decision on whether to observe the patient in the ED and wait until the workup is completed or to admit and then evaluate the patient in the ward. If the clinicians cannot obtain enough information to evaluate the patient for appropriate management, short-term admission may be an option to reduce the LOS and to provide a stable evaluation.

Simultaneous Nosocomial SARS-CoV-2 Outbreaks with Different Patterns of Occurrence in Two General Wards; Experience in a Tertiary Care Hospital in Korea

A nosocomial outbreak of severe acute respiratory syndrome-coronavirus-2 occurred in two general wards. One outbreak had pre-symptomatic transmission and was linked epidemiologically with an index case. The other outbreak was associated with early detection failure in a crowded room. Notably, adherence to appropriate mask wearing was not confirmed in the hospital outbreak. Confirmed cases were moved into isolation rooms, and contacts were quarantined. Quarantined cases were tested regularly and facilitated early termination of the hospital outbreak.

A Study on the Characteristics of Intentional Self-Poisoning Patients :Comparison between Non-Prescription and Prescription Drugs / 정신신체의학

Objectives@#：Self-poisoning is the leading cause of visits to the emergency departments after a suicide attempts. This study is aimed to compare the patient characteristics according to the category of drugs ingested by the patients who attempted suicide. @*Methods@#：All medical charts were retrospectively reviewed from patients who visited the emergency center, at Seoul Medical Center, due to intentional self-poisoning from April of 2011 to July of 2019. We investigated the information regarding the subtype and quantity of the intoxication drug, how it was obtained, suicidal history, and psychiatric history, as well as, sociodemographic information. Variables were compared between prescription drug (PD) and non-prescription drug (NPD) poisoning groups. @*Results@#：The mean age of the NPD poisoning group was significantly lower than that of the PD poisoning group. The patient ratio of those enrolled in national health insurance and living with spouses were significantly higher in the NPD poisoning group. Compared to the NPD poisoning group, the PD poisoning group had a higher incidence of mental illnesses, underlying diseases and ratio of involuntary visit to the emergency department.Among the prescription drugs, the benzodiazepine poisoning group had a higher rate of self-prescription than the non-poisoning group, while the zolpidem poisoning group had a higher rate of the using someone else’s prescription than other drugs. Each single drug poisoning group (benzodiazepine, zolpidem, and antidepressant singleagent) had a higher rate of no mental illness than each of the mixed-poisoning group. @*Conclusions@#：Guidelines for regulating non-prescription drugs are needed as a matter of suicide prevention. Also, this study suggests that clinicians need to be careful when issuing prescriptions and should suicidal risk according to patients’ characteristics, duration of follow-up and type of drug packaging.

A Study on the Characteristics of Intentional Self-Poisoning Patients :Comparison between Non-Prescription and Prescription Drugs / 정신신체의학

Objectives@#：Self-poisoning is the leading cause of visits to the emergency departments after a suicide attempts. This study is aimed to compare the patient characteristics according to the category of drugs ingested by the patients who attempted suicide. @*Methods@#：All medical charts were retrospectively reviewed from patients who visited the emergency center, at Seoul Medical Center, due to intentional self-poisoning from April of 2011 to July of 2019. We investigated the information regarding the subtype and quantity of the intoxication drug, how it was obtained, suicidal history, and psychiatric history, as well as, sociodemographic information. Variables were compared between prescription drug (PD) and non-prescription drug (NPD) poisoning groups. @*Results@#：The mean age of the NPD poisoning group was significantly lower than that of the PD poisoning group. The patient ratio of those enrolled in national health insurance and living with spouses were significantly higher in the NPD poisoning group. Compared to the NPD poisoning group, the PD poisoning group had a higher incidence of mental illnesses, underlying diseases and ratio of involuntary visit to the emergency department.Among the prescription drugs, the benzodiazepine poisoning group had a higher rate of self-prescription than the non-poisoning group, while the zolpidem poisoning group had a higher rate of the using someone else’s prescription than other drugs. Each single drug poisoning group (benzodiazepine, zolpidem, and antidepressant singleagent) had a higher rate of no mental illness than each of the mixed-poisoning group. @*Conclusions@#：Guidelines for regulating non-prescription drugs are needed as a matter of suicide prevention. Also, this study suggests that clinicians need to be careful when issuing prescriptions and should suicidal risk according to patients’ characteristics, duration of follow-up and type of drug packaging.

Comparison of cobas EGFR Mutation Test v2 and PANAMutyper-R-EGFR for Detection and Semi-Quantification of Epidermal Growth Factor Receptor Mutations in Plasma and Pleural Effusion Supernatant

BACKGROUND: Plasma epidermal growth factor receptor (EGFR) mutation tests are less invasive than tissue EGFR mutation tests. We determined which of two kits is more efficient: cobas EGFR Mutation test v2 (cobasv2; Roche Molecular Systems, Pleasanton, CA, USA) or PANAMutyper-R-EGFR (Mutyper; Panagene, Daejeon, Korea). We also evaluated whether pleural effusion supernatant (PE-SUP) samples are assayable, similar to plasma samples, using these two kits. METHODS: We analyzed 156 plasma and PE-SUP samples (31 paired samples) from 116 individuals. We compared the kits in terms of accuracy, assessed genotype concordance (weighted κ with 95% confidence intervals), and calculated Spearman's rho between semi-quantitatively measured EGFR-mutant levels (SQIs) measured by each kit. We also compared sensitivity using 47 EGFR-mutant harboring samples divided into more-dilute and less-dilute samples (dilution ratio: ≥ or <1:1,000). RESULTS: cobasv2 tended to have higher accuracy than Mutyper (73% vs 69%, P=0.53), and PE-SUP samples had significantly higher accuracy than plasma samples (97% vs 55–71%) for both kits. Genotype concordance was 98% (κ=0.92, 0.88–0.96). SQIs showed strong positive correlations (P<0.0001). In less-dilute samples, accuracy and sensitivity did not differ significantly between kits. In more-dilute samples, cobasv2 tended to have higher sensitivity than Mutyper (43% vs 20%, P=0.07). CONCLUSIONS: The kits have similar performance in terms of EGFR mutation detection and semi-quantification in plasma and PE-SUP samples. cobasv2 tends to outperform Mutyper in detecting less-abundant EGFR-mutants. PE-SUP samples are assayable using either kit.

The Effect of Low Birth Weight and Age on the Cognitive Performance of Preterm Preschoolers

OBJECTIVES: The current study examined the effect of birth weight on the relationship between age and IQ of children, who were born preterm with very low birth weight (VLBW) or extremely low birth weight (ELBW). METHODS: The study subjects were 82 children, aged between 3–5 years, who visited the neonatal intensive care unit of a university hospital located in Seoul. The children had been born prematurely with VLBW or ELBW. Their IQ was tested using the performed Korean-Wechsler Preschool and Primary Scale of Intelligence fourth edition. RESULTS: A hierarchical regression analysis showed a significant interaction effect of birth weight and age on Full Scale IQ (FSIQ); the effect of age on FSIQ differed according to birth weight. For the group with VLBW, FSIQ was more likely to be higher with increasing age. Conversely, for the group with ELBW, FSIQ remained low regardless of the age level. In addition, birth weight and age had a significant interaction effect on the Visual Spatial Index. Birth weight had a significant main effect on Verbal Comprehension Index. CONCLUSION: This research suggested the possibility of predicting the cognitive developmental of premature children, by highlighting the fact that prematurely born children, with VLBW/ELBW, have different cognitive developmental trajectories.

Appropriate oral antibiotics for bone and joint infections based on the susceptibility of clinical Staphylococcus aureus isolates

No abstract available.

A Multicentre Study about Pattern and Organisms Isolated in Follow-up Blood Cultures / 대한임상미생물학회지

BACKGROUND: This study analysed patterns of requests for repeated blood cultures and the microorganisms isolated in follow-up cultures. METHODS: The frequencies and intervals of repeated blood cultures performed during January and February of 2010 at seven university-affiliated hospitals in Korea were evaluated. Results of microbiological cultures at follow-up were analysed with respect to pathogen replication, immune clearance, appearance of new pathogens, and skin contaminants. RESULTS: Among 3,072 patients who received repeated blood cultures, the average number of requests was 3.2. Of the 5,241 follow-up blood culture events recorded, durations of 1, 2, and 3 days between cultures were identified for 23.1%, 21.4%, and 15.0% of events, respectively. Relative to each initial culture, persistent pathogen growth in subsequent culture(s) accounted for 2.3% of events, whereas immune clearance was confirmed in 8.5% of events. Previously undetected pathogens were isolated in 5.2% of the follow-up cultures, the majority of which grew after an interval of six days. Skin contaminants were detected in 7.6% of the repeated cultures, and 76.1% of the follow-ups displayed no growth of microorganisms. CONCLUSION: The most common numbers of repeat culture requests were two and three, and these were typically performed within three days of the initial culture. Among the follow-up cultures, new pathogens were identified in 5.2%, and the majority of this group likely presented for follow-up during a new disease episode.

Comparison of anthropometric data and clinical health indicators according to the serum vitamin B12 status in female older adults living in a rural area of Jeonla province, Korea / 한국영양학회지

Subclinical vitamin B12 deficiency is common in the elderly worldwide. We investigated the change of serum vitamin B12 concentration with aging and compared anthropometric data and clinical health indicators between normal (> or = 340 pg/mL) and low (< 340 pg/mL) serum vitamin B12 groups in 470 Korean women aged 65 years and over living in a rural area. Serum vitamin B12 concentration showed inverse correlation with age (r = -0.0992, p < 0.05). The normal B12 group showed significantly (p < 0.05) higher red blood cell count, hemoglobin, and hematocrit compared to the low B12 group, however, no difference in mean corpuscular volume was observed between the two groups. The normal B12 group showed significantly lower serum homocysteine concentration (p < 0.01) and prevalence of vitamin D (p < 0.01) or folate deficiency (p < 0.001). Bone mineral density (T-score) was significantly higher (p < 0.05) in the normal B12 group, compared with that in the low B12 group, and showed positive correlation (r = 0.1490, p < 0.01) with serum vitamin B12 concentration after adjusting for age, body weight, and body mass index. No differences in anthropometric data, physical activity, and smoking and drinking habits were observed between the two groups. In conclusion, it could be suggested that older female adults with normal serum vitamin B12 level would be less anemic and osteoporotic and more resistant to hyperhomocysteinemia associated chronic diseases than those with low serum vitamin B12 level.

Acute viral gastroenteritis in children hospitalized in Iksan, Korea during December 2010-June 2011 / 소아과

PURPOSE: Viral etiology is common in cases of children with acute diarrhea, and antibiotic therapy is usually not required. Therefore, it is important to determine the distribution of common viruses among children hospitalized with acute diarrhea. METHODS: We included 186 children who suffered from acute diarrhea and were hospitalized at the Wonkwang University Hospital Pediatric ward from December 1, 2010 to June 30, 2011 in this study. Stool samples were collected and multiplex reverse transcriptase polymerase chain reaction (multiplex RT-PCR) was used to simultaneously determine the viral etiology such as rotavirus, norovirus, astrovirus, or adenovirus. RESULTS: Causative viruses were detected in 72 of the 186 cases (38.7%). The mean age of the virus-positive cases was 1 year and 9 months (range, 1 month to 11 years). Rotavirus was detected in 50/186 (26.9%); norovirus, in 18/186 (9.7%); and astrovirus, in 3/186 cases (1.6%). Adenovirus was not detected in any of the cases. Proportions of norovirus genogroups I and II were 21.1% and 78.9%, respectively. Four of the 51 rotavirus-positive cases (7.8%) had received rotavirus vaccination at least once. The mean duration of diarrhea was 2.8 days (range, 1 to 10 days) and vomiting occurred in 39 of the 72 cases (54.2%). CONCLUSION: Viral etiology was confirmed in about one-third of the children with acute diarrhea, and the most common viral agent was rotavirus, followed by norovirus.

Sensitivities of seasonal and pandemic rapid antigen tests differentiated by the level of immunofluorescence for the detection of pandemic influenza A/H1N1 2009 virus

No abstract available.

Evaluation of ExiPrep16 Automated System for the Extraction of Nucleic Acids from Nasopharyngeal Swabs for the Detection of Respiratory Viruses

BACKGROUND: Automated nucleic acid extraction offers a standardized sample treatment method, low error rate, and avoids sample nucleic acid contamination for use in molecular diagnostics. Here, we evaluated the performance of automated ExiPrep16 system (Bioneer Co.) in comparison with the manual Viral Gene-spin Viral DNA/RNA Extraction kit (VGspin; iNtRON Biotechnology Inc.) for the detection of respiratory viruses from nasopharyngeal flocked swabs. METHODS: To compare the agreement rate and analytical sensitivity between ExiPrep16 and VGspin, previously collected 78 patient samples and 11 pooled samples of each respiratory viruses and their serially diluted samples (until 1/10(8)), were tested by multiplex reverse-transcriptase PCR (Seeplex RV 12 ACE Detection kit; SeeGene Inc.). In addition, we repeatedly analyzed the threshold cycle of the pooled and 1/10(3) dilution of adenovirus (ADV) and influenza virus A (Flu-A) by using real-time PCR to evaluate the precision and crossover of the ExiPrep16 system. RESULTS: The analytical sensitivity of the ExiPrep16 was comparable to that of VGspin, and the highest detectable dilution varied in the range of 1/10 to 1/10(6) depending on the viruses. The total, overall positive and negative percent agreements of ExiPrep16 in comparison with VGspin were 95.7%, 96.2%, and 95.2%, respectively. The mean (CV%) of pooled and 1/10(3) dilution of ADV were, respectively, 19.2 cycle (2.1%) and 31.6 cycle (4.3%) and those for Flu-A were 22.6 cycle (3.1%) and 35.5 cycle (2.6%). No carryover was detected. CONCLUSIONS: Compared to the manual VGspin, ExiPrep16 ensured nucleic acid extraction for efficient detection of respiratory viruses.

Association between Elevated Pleural Interleukin-33 Levels and Tuberculous Pleurisy

BACKGROUND: Interferon-gamma (IFN-gamma) plays a crucial role in Mycobacterium tuberculosis induced pleural responses. Interleukin (IL)-33 up-regulates the production of IFN-gamma. We aimed to identify whether an association between pleural IL-33 levels and tuberculous pleurisy exists and determine its diagnostic value. METHODS: Pleural IL-33, ST2 (a receptor of IL-33), adenosine deaminase (ADA), and IFN-gamma, as well as serum IL-33 and ST2 were measured in 220 patients with pleural effusions (PEs). Patients with malignant (MPEs), parapneumonic (PPEs), tuberculous (TPEs), and cardiogenic (CPEs) pleural effusions were included. RESULTS: Pleural and serum IL-33 levels were highest or tended to be higher in patients with TPEs than in those with other types of PEs. The median pleural fluid-to-serum IL-33 ratio was higher in TPE cases (> or = 0.91) than in other PE cases (< or = 0.56). Pleural IL-33 levels correlated with those of pleural ADA and IFN-gamma. However, the diagnostic accuracies of pleural IL-33 (0.74) and pleural fluid-to-serum IL-33 ratio (0.75) were lower than that of ADA (0.95) or IFN-gamma (0.97). Pleural ST2 levels in patients with MPEs were higher than in patients with TPEs. Serum ST2 levels did not differ among the groups. CONCLUSIONS: We identified an association between elevated pleural IL-33 levels and tuberculous pleurisy. However, we recommend conventional pleural markers (ADA or IFN-gamma) as diagnostic markers of TPE.

Anthropometric Index, Dietary Habits and Nutrient Intake of the Oldest-old Population Aged 95 and Over Living in Seoul / 대한지역사회영양학회지

The population aged 95 years and older in Seoul approximately increased to five-fold over the past 10 years, while nationwide rates increased to three-fold. In order to examine the dietary habit and nutritional status of oldest-old population living in Seoul, we recruited 87 subjects (25 males and 62 females) aged 95 years and older. The prevalence of underweight (BMI or = 25 kg/m2) were 18.2% and 18.2% in males, and 20.8% and 9.4% in females, respectively. In self-assessment of health, only 25.3% answered to be unhealthy. More males exercised regularly and reported a wide range of activities than females. The average of %Kcal from carbohydrate, protein and fat (C : P : F) was 64.9 : 13.8 : 21.2 in males and 68.1 : 14.2 : 17.7 in females. The average daily energy intake was 1,307 kcal in males and 1,304 kcal in females. More than 75% of subjects were taking under estimated average requirements (EAR) for vitamin B1, B2 & C and Ca. The average of mean adequacy ratio (MAR) was 0.66 in males and 0.70 in females, and 28.8% of males and 12.9% of females were in MAR < 0.50. Based on MAR, 32.0% of males and 14.5% females were classified as normal and 16.0% of males and 25.8% of females were classified as malnourished. Our subjects were taking more animal food, especially milk and its products, compared to those living, in rural areas. However, a significant proportion did not meet the EAR for vitamin B1, B2 & C and Ca.

Number of Blood Cultures per 1,000 Patient Days at University-Affiliated Hospitals in Korea / 대한임상미생물학회지

The authors calculated the number of blood cultures per 1,000 admitted patient days at seven university-affiliated hospitals in 2010, which ranged from 65 to 129 (mean 110). The number of blood cultures per 1,000 patient days could possibly be a good parameter for assessing the appropriateness of blood culture.

Vitamin B12 content analysis of favorite Korean restaurant foods, convenient foods and bakery products

There is a limitation to estimate vitamin B12 intake due to the lack of data on vitamin B12 content of Korean commercial foods. In this study, vitamin B12 content was determined in favorite Korean restaurant foods, convenient or instant foods, fast foods and bakery products through a modified microbioassay using Lactobacillus delbrueckii ATCC 7830. Bulgogi and seafood & green pepper griddle had high vitamin B12 content, 3.50 and 2.96 microg/100 g, respectively. Pork suyook, pork griddle and pollack griddle had 0.48, 0.31 and 0.32 microg/100 g of vitamin B12, respectively. In stew, soft-tofu stew with seafood and doenjang stew with seafood had relatively high vitamin B12 content, 1.93 and 1.44 microg/100 g, respectively. Bibimbap and 4 different types of rice porridge, beef & mushroom, chicken & ginseng, seafood or abalone, had 0.36, 0.08, 0.09, 1.64 and 0.13 microg/100 g of vitamin B12, respectively. One serving of haejanggguk, yookejang, chuotang and galbitang had 5.97, 2.04, 2.63 and 1.91 microg of vitamin B12, respectively. One serving of samgetang and sulongtang had 2.89 microg and 6.64 microg of vitamin B12. In noodles, one serving of cram noodle soup, bibim-nangmyeon, and mul-nangmyeon had 18.8, 1.21 and 0.38 microg of vitamin B12, respectively. One regular gimbap and one triangle gimbap contained 1.09-2.53 and 0.54-1.11 microg of vitamin B12, respectively. One cheese-burger, chicken-burger and bulgogi-burger had 0.76, 0.62 and 0.54 microg of vitamin B12, respectively. A plain bagel and a waffle contained 0.13 and 0.17 microg/100 g of vitamin B12, respectively. Ready-made tomato sauce or cream sauce for spaghetti in a retort pouch contained only a trace of vitamin B12. In conclusion, these results should contribute to improving the present food vitamin B12 content database, most of which were cited from foreign data, thereby it could be helpful to estimate the vitamin B12 intake of Koreans more accurately than before. It will also provide new information for dietary education related to vitamin B12 and health.

Vitamin B12 Content Using Modified Microbioassay in Some Korean Popular Seaweeds, Fish, Shellfish and Its Products

There is a limitation to estimate vitamin B12 intake due to a lack of data on vitamin B12 content in many Korean foods. In this study, vitamin B12 content was determined in some seaweeds, fish, and shellfish and their product that are consumed in Korea using a modified microbioassay with Lactobacillus delbruecki ATCC 7830. Dried laver and dried seasoned and toasted laver contained very high levels of vitamin B12 (66.8 and 55.2-71.3 microg/100 g, respectively. Sea lettuce and seaweed fulvescene also contained high vitamin B12 content of 5.47-9.41 and 6.46-7.20 microg/100 g, respectively, whereas sea mustard and sea tangle contained low levels of vitamin B12; vitamin B12 was not detected in seaweed fusifome. Pacific saury, trout, sea-bass, or squid contained 12.01, 2.00, 0.49 and 2.33 microg vitamin B12/100 g, respectively. Ochellatus octopus, and naked sand lance contained 0.72-1.43 and 3.68 microg vitamin B12/100 g, respectively. Dried Alaska pollack contained 0.19-2.64 microg vitamin B12/100 g. Shellfish such as little neck clam and small ark shellfish contained high levels of vitamin B12 of 30.5-40.5 microg/100 g, and mussel and abalone contained 17.71 and 7.82 microg/100 g, respectively. Of unique Korean traditional fermented seafood products, salt-fermented products of squid (2.91 microg/100 g), clams (34.31 microg/100 g), Alaska pollack roe (9.98-12.02 microg/100 g), hairtail guts (4.58 microg/100 g) or small shrimp (0.58-1.55 microg/100 g), and fish sauce from anchovies (1.52-1.78 microg/100 mL), sand eel (0.22-0.24 microg/100 mL) or small shrimp (0.19-0.78 microg/100 mL) were analyzed. A few commercial brands of flying fish roe (0.73-1.73 microg/100 g), canned tuna (0.40 microg/100 g), and fried fish paste (0.25-0.69 microg /100 g) were also analyzed. In conclusion, vitamin B12 content in these foods, chosen considering the Korean food culture, should contribute to improve the present vitamin B12 food database. It may be helpful to estimate vitamin B12 intake more correctly than before, and provide additional information for dietary education related to vitamin B12 and meal management.

Characteristics of Microorganisms Isolated from Blood Cultures at Nine University Hospitals in Korea during 2009 / 대한임상미생물학회지

BACKGROUND: Blood culture is important for determining the etiologic agents of bacteremia and fungemia. Analyses of blood culture results and antimicrobial susceptibility can provide clinicians with relevant information for the empirical treatment of patients. The present study was conducted to assess the frequencies and antimicrobial resistance patterns of clinically important microorganisms from nine hospitals. METHODS: Data including microbiological isolates and corresponding antimicrobial susceptibility test results were collected during 2009 from nine and five university hospitals, respectively. Microorganism identification was based on conventional methods. Antimicrobial susceptibility was tested using the VITEK II system or the Clinical and Laboratory Standards Institute disk diffusion method. RESULTS: Of 397,602 blood specimens cultured from nine hospitals, 34,708 (8.7%) were positive for microorganisms. Excluding coagulase-negative Staphylococci (CoNS), Escherichia coli was the most common isolate (13.5%), followed by Staphylococcus aureus (11.5%), Klebsiella pneumoniae (6.5%) and Enterococcus faecium (3.4%). The isolation rate of CoNS was 23.6%, while that of ceftazidime-resistant E. coli showed geographic differences ranging from 11% to 28%. Among the Gram-negative isolates, A. baumannii displayed the highest levels of resistance. The total isolation rate of the Candida species increased compared to the previous reported rate in Korea. CONCLUSION: Among the isolates, CoNS was the most common, followed by E. coli and S. aureus. The gradual increase in the prevalence of extended-spectrum beta-lactamase (ESBL) producers has contributed to the increase in multi-drug resistance among bacterial isolates from bloodstream infections.

Comparison of Culture, Direct Immunofluorescence Assay, and Multiplex Reverse Transcriptase PCR for Detection of Respiratory Viruses

BACKGROUND: Rapid detection of causative viruses is important for the management of acute respiratory illnesses. To increase the detection rate and decrease the turnaround time (TAT) and cost, we used 24-well plates instead of R-mix shell vials and changes the report time from once on day 3 to twice on days 1 and 5 of culture. The detection rate and TATs of each culture method, direct immunofluorescence assay (DFA), and multiplex reverse transcriptase polymerase chain reaction (mPCR) were compared. METHODS: Among 2,062 nasopharyngeal swabs (NPSs) received from January 2009 to January 2011, 707 NPSs were cultured in R-mix shell vials and 1,355 NPSs were cultured in 24-well plates. We analyzed 538 NPSs simultaneously using DFA, mPCR, and culture and compared the detection rate for 7 viruses (adenovirus, influenza A and B virus; parainfluenza virus 1, 2, and 3; and respiratory syncytial virus [RSV]). RESULTS: The detection rate when using shell vials was 28.4% (201/707) and was 29.4% (399/1,355) on day 1 and 33.3% (452/1,355) on day 5 when using 24-well plates. In addition, of the 53 viruses that were detected on day 5, 34 were adenovirus, 7 were parainfluenza virus, 4 were influenza A virus, 3 were influenza B virus, 4 were RSV, and 1 was a mix of influenza B and parainfluenza virus. The TAT when using shell vials and 24-well plates was 4.8 days and 2.5 days, respectively. The detection rate for the 7 respiratory viruses using culture, DFA, and mPCR was 24.3%, 20.8%, and 38.5%, and the TAT was 3.7 days, 1.0 day, and 1.4 days, respectively. CONCLUSIONS: Using 24-well plates for virus culture is an efficient method for the detection of respiratory viruses.