Preliminary study on diagnosis of acute scrotum usingpoint-of-care ultrasonography by novice emergency residents:a comparison with conventional ultrasonography

Objective@#The diagnostic accuracy of novice residents in evaluating the scrotal pathology by point-of-care (POC) ultrasonography(US) was compared with that by the conventional US to determine the level of experience required toachieve competency. @*Methods@#Three novice residents underwent a one-day training course on identifying scrotal pathologies using POC US.They performed POC US on patients with an acute scrotum to identify five pathological findings. The diagnosis was confirmedby conventional scrotal US. The sensitivity and specificity of POC US by novice residents were calculated, and thechanges in sensitivity and specificity over time were observed. @*Results@#Sixty-two patients were included; the overall sensitivity and specificity were 76.7% (95% confidence interval [CI],61.3%-88.2%) and 78.9% (95% CI, 54.4%-93.9%), respectively. Decreased blood flow in the testicle showed very goodspecificity (100%; 95% CI, 93.8%-100.0%). The sensitivity and accuracy were variable at first 18 scans of each resident,but increased after 18 scans and were maintained over time. @*Conclusion@#Although the diagnostic accuracy of novice residents in evaluating the scrotal pathology using POC US wasvariable at first, the accuracy improved over time, especially after 18 scans of each resident. Nevertheless, larger, longtermresearch is needed to confirm the results of this study.

The method to reduce the malposition rate via reposition of guidewire with ultrasound guidance in the central venous catheterization

OBJECTIVE: Malposition of central venous catheterization (CVC) may cause vascular related complications and catheter dysfunctions. The aim of this study was to reduce the malposition rate of CVC by repositioning the malposition after confirming the location of the guide-wire with ultrasound (US) guidance. METHODS: This research assessed the before study (group A) from January to December 2016 and after study (group B) from January to December 2017 in the emergency department. CVCs were performed using the anatomical landmark technique (group A) and US guided technique (group B). In group B, if the guided-wire was misplaced, it was drawn back and repositioned under US guidance. The final location of the catheter tip was confirmed by chest X-ray. The rate of malposition before and after repositioning of the two groups was compared. RESULTS: The subjects were group A (694 cases) and group B (619 cases) with a total of 1,313 patients. The rate of malposition before repositioning of the two groups were 16 cases (2.3%) and 13 cases (2.1%), respectively, and no statistically significant difference was observed (P>0.05). In group B, there were 10 cases (1.6%) of guidewire malposition that was identified and three cases (0.5%) of catheter malposition could not be identified under US examination. The malpositioned guidewires were all corrected by repositioning under ultrasound guidance. The rate of malposition after repositioning of the two groups were 2.3% (n=16) and 0.5% (n=3), respectively, and a statistically significant difference was observed (P=0.009). CONCLUSION: With US guidance, confirming the location and repositioning CVC guidewire can reduce the malposition rate in CVCs.

Does the direction of J-tip of the guide-wire influence the misplacement of subclavian catheterization?

OBJECTIVE: Central venous catheter (CVC) misplacement can result in incorrect readings of the central venous pressure, vascular erosion, and intravascular thrombosis. Several studies have examined the correlation between the guidewire J-tip direction and misplacement rate. This study examined whether the guidewire J-tip direction (cephalad vs. caudad) affects the misplacement rate in right subclavian venous catheterization. METHODS: This prospective randomized controlled study was conducted between February 2016 and February 2017. The subjects were divided into two groups (cephalad group vs. caudad group) and the misplacement rate was compared according to guidewire J-tip direction in each group. RESULTS: Of 100 patients, the cephalad and caudad groups contained 50 patients each. The age, sex, and operator experience were similar in the two groups. In the cephalad group, misplacement of CVC insertion into the ipsilateral internal jugular vein occurred in two cases. In the caudad group, misplacement of CVC insertion into the contralateral subclavian vein occurred in one case, with loop formation in the brachiocephalic trunk in one case. Guidewire J-tip direction showed no significant correlation with CVC misplacement. CONCLUSION: The guidewire J-tip direction does not influence the rate of misplacement.

The influence of the decision making time by using point-of-care creatinine in patients with acute abdomen

OBJECTIVE: Radio-contrast abdomino-pelvic computed tomography (APCT) is considered the gold standard diagnostic tool for an acute abdomen in the emergency department. On the other hand, APCT has a risk of contrast-induced nephropathy. Emergency physicians evaluate the creatinine (Cr) level prior to taking a APCT for the above reason but it takes time to evaluation the serum Cr level. This study hypothesized that Cr measured by a point-of-care test (POCT) can shorten the time to making clinically important decisions for patients with an acute abdomen. METHODS: This prospective randomized study was conducted between March 2017 and October 2017. The subjects were divided into two groups (Cr measured by laboratory vs. Cr measured by POCT). To analyze the clinical acceptability for creatinine, agreement was demonstrated graphically by Bland-Altman plots. This study compared the time to make a clinically important decision by physicians and the length of stay at the emergency department in both groups. RESULTS: A total of 76 patients were eligible for the study, 38 patients were assigned to each group. There was no statistically significant difference in the time to the first medical examination (P=0.222) and emergency department stay time (P=0.802). On the other hand, the time to recognition of the Cr level (P < 0.001), time to performing APCT (P < 0.001), time to decision making (P < 0.001), and time to initiation of treatment (P < 0.001) were shortened significantly in the point-of-care creatinine group. CONCLUSION: In this study, the POCT for creatinine can allow rapid decision making by shortening the time to performing the radio-contrast APCT than the laboratory for patients with an acute abdomen.

Evaluation of Reverse Hybridization Assay for Detecting Fluoroquinolone and Kanamycin Resistance in Multidrug-Resistance Mycobacterium tuberculosis Clinical Isolates / 결핵및호흡기질환

BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB) is an increasing public health problem and poses a serious threat to global TB control. Fluoroquinolone (FQ) and aminoglycoside (AG) are essential anti-TB drugs for MDR-TB treatment. REBA MTB-FQ(R) and REBA MTB-KM(R) (M&D, Wonju, Korea) were evaluated for rapid detection of FQ and kanamycin (KM) resistance in MDR-TB clinical isolates. METHODS: M. tuberculosis (n=67) were isolated and cultured from the sputum samples of MDR-TB patients for extracting DNA of the bacilli. Mutations in genes, gyrA and rrs, that have been known to be associated with resistance to FQ and KM were analyzed using both REBA MTB-FQ(R) and REBA MTB-KM(R), respectively. The isolates were also utilized for a conventional phenotypic drug susceptibility test (DST) as the gold standard of FQ and KM resistance. The molecular and phenotypic DST results were compared. RESULTS: Sensitivity and specificity of REBA MTB-FQ(R) were 77 and 100%, respectively. Positive predictive value and negative predictive value of the assay were 100 and 95%, respectively, for FQ resistance. Sensitivity, specificity, positive predictive value and negative predictive value of REBA MTB-KM(R) for detecting KM resistance were 66%, 94%, 70%, and 95%, respectively. CONCLUSION: REBA MTB-FQ(R) and REBA MTB-KM(R) evaluated in this study showed excellent specificities as 100 and 94%, respectively. However, sensitivities of the assays were low. It is essential to increase sensitivity of the rapid drug resistance assays for appropriate MDR-TB treatment, suggesting further investigation to detect new or other mutation sites of the associated genes in M. tuberculosis is required.

Acquired Drug Resistance during Standardized Treatment with First-line Drugs in Patients with Multidrug-Resistant Tuberculosis / 결핵및호흡기질환

BACKGROUND: First-line drugs, if sensitive, are the most potent drugs in the treatment of multidrug-resistant tuberculosis (MDR-TB). This study examined the frequency and risk factors associated with acquired drug resistance to first-line drugs during a standardized treatment using first-line drugs in patients with MDR-TB. METHODS: This study included patients who were diagnosed with MDR-TB at the National Masan Tuberculosis Hospital between January 2004 and May 2008, treated with standardized first-line drugs, and for whom the preand post-treatment results of the drug susceptibility test were available. Their medical records were reviewed retrospectively. RESULTS: Of 41 MDR-TB patients, 14 (34.1%) acquired additional resistance to ethambutol (EMB) or pyrazinamide (PZA). Of 11 patients initially resistant to isoniazid (INH) and rifampicin (RFP), 3 (27.3%) acquired additional resistance to both EMB and PZA, and 3 (27.3%) to PZA. Of 18 patients initially resistant to INH, RFP and EMB, 6 (33.3%) acquired additional resistance to PZA. Of 6 patients initially resistant to INH, RFP and PZA, 2 (33.3%) acquired additional resistance to EMB. Ten of the 41 MDR-TB patients (24.4%) changed from resistant to susceptible. No statistically significant risk factors associated with acquired resistance could be found. CONCLUSION: First-line drugs should be used cautiously in the treatment of MDR-TB in Korea considering the potential acquisition of drug resistance.

Comparison of Smear and Culture Positivity using NaOH Method and NALC-NaOH Method for Sputum Treatment / 결핵및호흡기질환

BACKGROUND: Sputum decontamination with NALC-NaOH (N-acetyl-L-cysteine-sodium hydroxide) is known to better detect Mycobacterium tuberculosis (M. tb) by culture than that with using NaOH, which is widely used in Korean hospitals. In this report, sputum samples collected from pulmonary tuberculosis (TB) patients were treated with either NaOH or NALC-NaOH, and we compared the results of smear and culture positivity to determine whether the NALC-NaOH treatment method improves culture positivity in the sputum samples, and especially for those sputum samples that are smear negative and scanty. METHODS: For each decontamination method, 436 sputum samples from pulmonary TB patients in the National Masan Tuberculosis Hospital were collected for this study. Sputum from a patient was collected two times for the first and second day of sampling time, and these samples were employed for the decontamination process by performing the 4% NaOH and NALC-2% NaOH treatment methods, respectively, for detecting M. tb by an AFB (Acid Fast Bacilli) smear and also by culture in solid Ogawa medium. RESULTS: The NaOH and NALC-NaOH treatment methods did not significantly affect the AFB smear positivity of the sputum samples (33.0% vs 39.0%, respectively, p=0.078). However, the culture positive percents of M. tb in the Ogawa medium treated with NALC-NaOH and NaOH were 39.7% and 28.0%, respectively, which was a significantly different (p=0.0003). This difference in culture was more prominent in the sputum samples that were smear negative (the positive percents with NALC-NaOH and NaOH were 15.8% and 7.2%, respectively, p=0.0017) and scanty (NALC-NaOH and NaOH were 60.8% and 42.9%, respectively, p=0.036), but not for a smear that was 1+ or higher (p>0.05). CONCLUSION: NALC-NaOH treatment is better than NaOH treatment for the detection of M. tb by culture, but not by smear, and especially when the AFB smear is negative and scanty.

Risk Factors for Primary Multidrug Resistant Tuberculosis / 결핵및호흡기질환

BACKGROUND: Primary multidrug-resistant tuberculosis is defined as Mycobacterium tuberculosis isolates that are resistant to at least isoniazid and rifampin in never-been-treated tuberculosis patients, and this malady is caused by the transmission of a resistant strain from one patient, who is infected with a resistant Mycobacterium tuberculosis strain, to another patient. The prevalence of primary multidrug-resistant tuberculosis could be a good indicator of the performance of tuberculosis control programs in recent years. We conducted a case-control study to identify the risk factors for primary multidrug-resistant tuberculosis. METHODS: From January 1, 2001 to, June 30, 2003, by conducting prospective laboratory-based surveillance, we identified 29 hospitalized patients with P-MDRTB and these patients constituted a case group in this study. The controls were represented by all the patients with culture-confirmed drug susceptible tuberculosis who were admitted to National Masan Hospital during the same study period. The odds ratios for the patients with primary multidrug-resistant tuberculosis, as compared with those of the patients with drug susceptible tuberculosis, were calculated for each categorical variable with 95% confidence intervals. RESULTS: Multivariate logistic regression showed that the presence of diabetes mellitus (odds ratio 2.68; 95% confidence interval, 1.05-6.86) was independently associated with having primary multidrug-resistant tuberculosis. CONCLUSION: This study has shown that diabetes mellitus might be one of the risk factors for primary multidrug-resistant tuberculosis.