Infection and Chemotherapy最新文献

Background: Nocardiosis is a rare, but potentially life-threatening condition. It is difficult to diagnose, and bacterial culture identification can be time consuming. We investigated the characteristics of nocardiosis and the suitability of the treatment approach in Korea.

Materials and methods: This retrospective study was conducted at 5 medical institutions between 2011 and 2021. We reviewed the medical records of patients with microbiologically confirmed nocardiosis. Appropriate antibiotic selection was defined as follows: (1) selecting antibiotics according to the species, (2) if the species of Nocardia was unknown, trimethoprim-sulfamethoxazole-based therapy or linezolid-based therapy was administered, and (3) selection of antibiotics using the antibiotic susceptibility test. The appropriate treatment periods for antibiotics were defined as treatment maintained from 3 to 12 months, depending on involvement of the organs. Descriptive analysis and Fisher exact test were used. Statistical significance was set at P-values of <0.05.

Results: Thirty patients were enrolled. Of these patients, 18 (60.0%) were male. The median age was 70.5 years. Among the diagnosed patients, 12 (40.0%) had an immunocompromised status. Eight (30.0%) patients received optimal treatment for the appropriate treatment period. Appropriate dosing duration was observed in 3 of the 12 (25.0%) immunocompromised patients. There was no significant difference between the presence or absence of immunosuppression and the adequacy of treatment for nocardiosis (P = 1.000). Skin and soft tissue (14 patients) were most frequently involved in this study. Nocardia species (spp.) were isolated from culture at a median of 6.0 days. There were 7 cases with N. farcinica (23.3%).

Conclusion: We found that 60.0% of the patients with nocardiosis did not have an immunocompromised status. Further, 26.7% of the total patients received adequate treatment for nocardiosis. The reasons for suboptimal management of nocardiosis in Korea are presumed to be diagnostic difficulties, lack of awareness about nocardiosis, and difficulties in selecting antibiotics for Nocardia spp. among clinicians. The lack of antibiotic susceptibility tests for Nocardia spp. could be the source of these problems. Nocardiosis should be suspected in cases of recurrent infections with skin and soft tissue, musculoskeletal, or respiratory system involvement with or without an immunocompromised status. Clinical microbiological support is required for the diagnosis and selection of antibiotics in Korea. High clinical index of suspicion and clinical microbiological support are required for the accurate diagnosis of nocardiosis in Korea.

Background: Enterovirus D68 (EV-D68) is a re-emerging pathogen that is particularly common in children and may cause asthma-like respiratory infection and acute flaccid myelitis. However, in Korea, EV-D68 has never been reported thus far. This study aimed to identify EV-D68 from nasopharyngeal aspirates (NPAs) in Korean children with a respiratory tract infection.

Materials and methods: The EV-D68 reference strain was purchased and blindly used to assess the detection ability of three commercial and one in-house mRT-PCR kit in 2018. Then, we selected children whose specimens were positive for human rhinovirus (HRV) and/or enterovirus (EV) by Allplex mRT-PCR (Seegene, Inc., Seoul, Korea) from April to December 2022. Total RNA was extracted from NPAs, and a partial 5'-UTR gene was amplified and sequenced for the identification of HRV/EV species. Additionally, PCR targeting the VP1 gene was performed to assess EV-D68-positive NPAs, followed by sequencing. Phylogenetic analysis and comparison of amino acid sequence alignments were performed using a partial VP1 gene of our and recent international EV-D68 strains.

Results: Among the mRT-PCR kits tested, only the in-house kit was able to detect EV-D68 in 2018. However, we detected three EV-D68 strains among children hospitalized with fever and/or respiratory symptoms in September - December 2022 who tested positive for EV by the Allplex kit. Two of them were healthy toddlers with lower respiratory infections accompanied by new-onset wheezing but no neurologic complications. Among 34 children with lower respiratory infection who tested positive for HRV during the same period, EV-D68 was not detected. Phylogenetic analysis revealed that the first Korean EV-D68 belonged to subclade B3. Amino acid sequence alignment of international subclade B3 EV-D68 strains also showed that our strain is genetically more related to those from Europe than those from Japan.

Conclusion: We first detected EV-D68 in three Korean children who had EV detected by the Allplex mRT-PCR kit in 2022. EV-D68 also circulated in Korea in fall 2022, but the prevalence and severity seemed to be lower than those in previous reports from other countries.

Background: There have been few studies on the outcome of acute coronary syndrome (ACS) in human immunodeficiency virus (HIV) infection in the era when antiretroviral therapy (ART) is generalized and most of them have achieved viral suppression. Using claims data, we aimed to assess the mortality after atherosclerotic cardiovascular events in people with HIV (PWH) who maintain optimal adherence to ART.

Materials and methods: We used claims data from the National Health Insurance of the Korea to confirm newly diagnosed PWH from 2009 to 2019, and measured ART adherence. ACS and mortality were confirmed in PWH who showed optimal adherence to ART.

Results: Among 7,100 PWH with optimal adherence and during 27,387 person-year of follow-up duration, ACS was confirmed in 140 (2.0%) cases, which was 1.3 times greater than statistics of the Korean general population (511.0 vs. 383.1 per 100,000). Acquired immunodeficiency syndrome, hypertension, dyslipidemia, and diabetes mellitus were associated with the development of ACS in PWH with optimal adherence. Mortality was confirmed in 10 cases, which is 7.1% overall and 2.9% when limited to myocardial infarction. It was comparable with the mortality rate of the Korean general population after myocardial infarction (8.9%).

Conclusion: ACS prevalence was higher in PWH even when optimal adherence was maintained. However, mortality after ACS was comparable to that in the HIV-negative population.

Background: The 2015 Middle East respiratory syndrome (MERS) coronavirus outbreak in Korea led to profound emotional and social burdens, especially in patients and health care professionals.

Materials and methods: Focus group interviews were conducted with 2 patients, 1 family member and 6 health care professionals about psychological distress related to MERS in 2017 and analyzed the interview data using the consensual qualitative research method.

Results: Four domains and 17 core ideas were identified within three interview groups, including psychological distress during the outbreak, problems regarding the response to the outbreak, positive experiences, and future directions for enhancing intervention to improve mental health and prevent psychosocial problems during the outbreak. Psychological consequences were affected by the characteristics of the emerging infectious disease and the structure and process of institutional or governmental response to the MERS outbreak. Mental health services and psychosocial support reduced the negative impact on psychological distress.

Conclusion: The MERS outbreak in 2015 gave rise to emotional and social injuries to patients and health care professionals, some of which can be long-lasting constraints in their lives. Preparedness in a society's response to a pandemic considering mental health in related parties can minimize negative psychological consequences and enhance resilience at the individual and society levels.

Although adult immunization is different from children's, vaccine preventable diseases (VPDs) for adults are significant in that they are more severe and cause more deaths than VPDs for children. Additionally, the emergence of new vaccines and an increase in the elderly population are increasing demands for policy support for adult vaccination. Accordingly, in this paper, I will look at the characteristics of adult immunization, policies that have been implemented in Korea, and considerations.

Background: Chryseobacterium indologenes is ubiquitous in nature and rarely causes infections. However, the clinical impact of C. indologenes has increased in recent years, especially in immunocompromised patients, and has resulted in high mortality rates. We aimed to investigate the clinical and microbiological characteristics of C. indologenes bacteremia.

Materials and methods: We retrospectively reviewed medical records of a 642-bed university-affiliated hospital in Korea, dating from January 2001 to December 2020, to investigate C. indologenes bacteremia.

Results: A total of 22 C. indologenes isolates were identified from blood culture records. All patients were hospitalized at the time of bacteremia, and the most common manifestation was primary bacteremia. A sizable majority of the patients (83.3%) had underlying diseases, and all patients received intensive care unit care during their admission. The 14-day and 28-day mortality rates were 8.3% and 16.7%, respectively. Importantly, all C. indologenes isolates were 100% susceptible to trimethoprim-sulfamethoxazole.

Conclusion: In our study, most of the infections were hospital-acquired, and the susceptibility pattern of the C. indologenes isolates showed multidrug resistance. However, trimethoprim-sulfamethoxazole is a potentially useful antibiotic for C. indologenes bacteremia treatment. More attention is required to identify C. indologenes as one of the most important nosocomial bacteria with detrimental effects in immunocompromised patients.

Background: Sporadic measles outbreaks have continued to occur in Korea, mainly in adults in their 20s and 30s, most notably in 2014 and 2019. We here evaluated the possible causes of a low seroprevalance of measles by testing young healthcare workers (HCWs).

Materials and methods: This study was conducted in a 2,743-bed tertiary-care hospital in Seoul between 2020 and 2021. We performed a measles antibody test (chemiluminescence immunoassay), measured the IgM/IgG index ratio, and conducted an avidity test at 1-month after Measles-Mumps-Rubella (MMR) vaccination in HCWs who had been seronegative for measles. Measles vaccination histories were obtained from the national vaccine registry.

Results: Of the 3,173 HCWs newly employed in our hospital during the study period, 54 with a negative measles IgG at commencement were enrolled. Thirty six (67%) of these subjects were female, and the median age was 25 years (interquartile range [IQR]: 24 - 27). Fourty nine (91%) showed seroconversion at 1 month after the first vaccination. Of these individuals, 38 received both measles IgM and IgG test, and all had an IgM/IgG index <1. Of the 49 seroconverters, all HCWs showed a high avidity index. According to the national immunization registry, 45 (83%) received at least 2 doses of an MMR vaccination.

Conclusion: Secondary vaccine failure may underlie vaccine failure in young Korean adults. HCWs born after 1985 with a negative measles antibody may need only a single dose booster vaccination rather than a 2-dose vaccination regimen.

Background: There are limited data on the clinical characteristics and the vertical transmission rate of pregnant women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and their neonates in Korea.

Materials and methods: Pregnant women who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were retrospectively reviewed in Asan Medical Center from September 1, 2020, to April 26, 2022. All neonates and infected women underwent a polymerase chain reaction test for severe acute respiratory syndrome corona virus 2 within 24 hours of birth and at 48-hour interval if they stayed in the hospital.

Results: A total of 60 pregnant women gave birth by cesarean section (n = 40, 66.7%) or vaginal delivery (n = 20, 33.3%). Among them, 3 women gave birth to twins. Delivery occurred, on average, at 38⁺² weeks (± 2⁺⁰) of gestational age, and 9 patients (15.0%) had underlying diseases. Of these 60 patients, 9 (15.0%) received coronavirus disease 2019 vaccinations. Pneumonia was confirmed by a chest radiograph in 7 patients (11.7%), and 2 patients (3.3%) required supplemental oxygen therapy, both of whom eventually recovered. The mean birthweight of the neonates was 3,137 g (± 557.6). Further, 8 neonates (12.7%) were of low-birth weight (< 2,500 g), and 11 neonates (17.5%) were preterm (<37 weeks of gestation). Apgar score was median 8 (8 - 9) at 1 minute and 9 (9 - 9.5) at 5 minutes. Four neonates (6.3%) required invasive mechanical ventilation. All neonates had negative SARS-CoV-2 test results. Therefore, there was no vertical transmission in 63 of the neonates (0%, 95% confidence interval [CI]: 0 - 6).

Conclusion: Pregnant Korean women with SARS-CoV-2-infection had favorable obstetric outcomes, and the risk of vertical transmission to their neonates was low. Managing the infection risks of pregnant women and their neonates during the coronavirus disease 2019 pandemic are required.

Late-onset Pneumocystis jirovecii pneumonia (PCP) can be developed in solid organ transplant (SOT) patients. Granulomatous P. jirovecii pneumonia (GPCP) can occur in immunocompromised patients, but has rarely been reported in SOT recipients. The diagnosis of GPCP is difficult since the sensitivity of sputum and bronchoalveolar lavage is low and atypical patterns are shown. A 60-year-old man, who had undergone renal transplantation 24 years ago presented with nodular and patchy lung lesions. He was asymptomatic and stable. After empirical treatment with a fluoroquinolone, the condition partially resolved but relapsed 4 months later. The pulmonary nodule was resected, and GPCP was confirmed. The pathogenesis of GPCP remains unclear, but in SOT recipients presenting with an atypical lung pattern, GPCP should be considered. This case was discussed at the Grand Clinical Ground of the Korean Society of Infectious Disease conference on November 3, 2022.

Background: Abacavir/dolutegravir/lamivudine has been indicated in Korea since 2015 for treatment of human immunodeficiency virus type 1 (HIV-1) infection in combination. This regulatory post-marketing surveillance (PMS) study evaluated the real-life safety and effectiveness of abacavir/dolutegravir/lamivudine in patients with HIV-1 in clinical practice in Korea.

Materials and methods: This open-label post-marketing surveillance examined data from consecutive patients (aged ≥12 years) with HIV-1 infection receiving abacavir/dolutegravir/lamivudine according to locally approved prescribing information; treatment-naïve and treatment-experienced patients were permitted. Data regarding patient demographics, medical history, clinical characteristics, medications (HIV-1 related and concomitant), resource utilization and comorbidities were extracted from patient records over a 1-year treatment period. Outcomes included safety of abacavir/dolutegravir/lamivudine (primary endpoint) and real-life effectiveness according to physician's global assessment and the proportion of patients with plasma HIV-1 RNA count <50 copies/mL at 48 weeks.

Results: Of 663 patients treated with abacavir/dolutegravir/lamivudine at 27 centers in Korea (June 2015 - June 2021), 656 were eligible for the safety analyses and 484 for effectiveness analyses. Patients were mostly male (94.8%) mean age was 42.2 ± 14.0 years and mean weight was 68.1 ± 11.0 kg. Adverse events (AEs, n = 656 in total) were mostly mild in severity, with the most common being nasopharyngitis (7.9%), retching (7.5%), headache (4.9%). Of 121 adverse drug reactions (ADRs), the most frequent were retching (4.4%), headache (1.8%) and dizziness (1.7%). Of 55 serious AEs, the most frequent were anogenital warts (1.1%). Of 2 serious ADRs, nothing was unexpected, and both resolved. The risk of experiencing an AE while receiving abacavir/dolutegravir/lamivudine appeared to be especially increased in patients receiving concomitant medications for other conditions. Abacavir/dolutegravir/lamivudine effectively suppressed HIV-1 (96.1% of patients had plasma HIV-1 RNA <50 copies/mL), and 99.0% of patients showed symptom improvement based on physician assessment.

Conclusion: Results of this PMS study showed that abacavir/dolutegravir/lamivudine administered as highly active antiretroviral therapy was well tolerated and effective in patients with HIV-1 infection.