Prevalence of Ocular Candidiasis and Candida Endophthalmitis in Patients With Candidemia: A Systematic Review and Meta-Analysis.

BACKGROUND: Infectious diseases and ophthalmology professional societies have disagreed regarding ocular screening in patients with candidemia. We aimed to summarize the current evidence on the prevalence of ocular candidiasis (OC) and Candida endophthalmitis (CE) according to the standardized definitions. METHODS: A literature search was conducted from the inception date through 16 October 2022 using PubMed, Embase, and SCOPUS. Pooled prevalence of ocular complications was derived from generalized linear mixed models (PROSPERO CRD42022326610). RESULTS: A total of 70 and 35 studies were included in the meta-analysis for OC and concordant CE (chorioretinitis with vitreous involvement), respectively. This study represented 8599 patients with candidemia who underwent ophthalmologic examination. Pooled prevalences (95% CI) of OC, overall CE, concordant CE, and discordant CE were 10.7% (8.4-13.5%), 3.1% (2.1-4.5%), 1.8% (1.3-2.6%), and 7.4% (4.5-12%) of patients screened, respectively. Studies from Asian countries had significantly higher concordant CE prevalence (95% CI) of patients screened (3.6%; 2.9-4.6%) compared with studies from European countries (1.4%; .4-5%) and American countries (1.4%; .9-2.2%) (P <.01). Presence of total parenteral nutrition and Candida albicans was associated with CE, with pooled odds ratios (95% CI) of 6.92 (3.58-13.36) and 3.02 (1.67-5.46), respectively. CONCLUSIONS: Prevalence of concordant CE overall and among Asian countries was 2 and 4 times higher than the prevalence previously reported by the American Academy of Ophthalmology (AAO) of <0.9%, respectively. There is an urgent need to study optimal screening protocols and to establish joint recommendations by the Infectious Diseases Society of America and AAO.

A fluorescence-based sweat test sensor in a proof-of-concept clinical study for COVID-19 screening diagnosis.

During the corona virus disease 2019 (COVID-19) pandemic period, rapid screening of covid-19 patients has been of great interest by developing a fluorescent sensor for complexation with nonanal, which is a marker for Covid-19 detection in sweat. Solid phase micro-extraction gas chromatography-mass spectrometry (SPME GC-MS) was initially used to quantify nonanal in armpit sweat samples based on an external calibration curve. A sample containing a nonanal content above the threshold of 1.04 µL is expected to be COVID-19 positive with a sensitivity and specificity of 87% and 89%, respectively, validated by comparison with RT-PCR results. For more practical applications, helicene dye-encapsulated ethyl cellulose, namely EC@dyeNH, was applied to screen 140 sweat samples collected from the foreheads of volunteers. The mixed sensor and sweat solution droplets were then visualized and imaged under blacklight. The COVID-19 positive droplets exhibited yellow fluorescence emission, the brightness of which could be measured by using ImageJ in the grey scale. With the optimum color intensity of >73 for positive results, the screening performance was observed with a sensitivity and specificity of 96% and 93%, respectively. The overall test time of this method is approximately less than 15 min. This alternative method offers a promising practical screening approach for the diagnosis of COVID-19 in sweat.

Self-enhancement lateral flow immunoassay for COVID-19 diagnosis.

Equipment-free colorimetric-based lateral flow immunoassay (LFIA) is the most convenient and popular tool for various applications, including diagnostic tools requiring high sensitivity for the detection of pathogens. Thus, improvements and developments of LFIA are constantly being reported. Herein, we enriched the sensitivity of LFIA using the gold enhancement principle, emphasizing needlessly complicated apparatus, only one step for the strip test operation, and typical time incubation (15 min) process. Self-enhanced LFIA was then executed for subsequent flows by overlapping the additionally enhanced pad composed of gold ions and reducing agent on the conjugate pad and the sample pad. Self-enhanced LFIA was performed to detect SARS-CoV-2 antigens in saliva. The obtained result depicted that the achieved sensitivity was up to tenfold compared with that of conventional LFIA by visual measurements. The detection limits of self-enhanced LFIA detecting nucleocapsid protein antigens in the saliva sample was 0.50 and 0.10 ng/mL employed by naked eye detection and calibration curve-based calculation, respectively. When the proposed device was applied to 207 human saliva samples, the diagnostic performance presented a 96.10 % sensitivity and 99.23 % specificity. This self-enhanced LFIA could be implemented in large-scale production and demonstrates higher sensitivity with effortless use, which meets the requirements for point-of-care testing and on-field mass screening.

Host genetic factors of COVID-19 susceptibility and disease severity in a Thai population.

Host genetic factors have been shown to play a role in SARs-CoV-2 infection in diverse populations. However, the genetic landscape differs among various ethnicities; therefore, we explored the host genetic factors associated with COVID-19 disease susceptivity and disease severity in a Thai population. We recruited and genotyped 212 unrelated COVID-19 Thai patients and 36 controls using AxiomTM Human Genotyping SARs-COV-2 array, including 847,384 single nucleotide polymorphisms related to SARs-COV-2 pathogenesis, immune response, and related comorbidity No SNPs passed the genome-wide significance threshold of p value <1 × 10-8. However, with a threshold of p value <1 × 10-5, a locus on chromosome 5q32 was found to have a suggestive association with COVID-19 disease susceptibility (p value 6.9 × 10-6; Q-Q plot λ = 0.805, odds ratio 0.02). Notably, IL17B is a gene located in this linkage disequilibrium block and is previously shown to play a part in inflammation and pneumonia. Additionally, a suggestive locus on chromosome 12q22, harboring EEA1 and LOC643339, was associated with COVID-19 disease severity (p value 1.3 × 10-6 - 4.4 × 10-6, Q-Q plot λ = 0.997, odds ratio 0.28-0.31). EEA1 is involved in viral entry into cells, while LOC643339 is a long non-coding RNA. In summary, our study suggested loci on chromosomes 5q32 and 12q22 to be linked to COVID-19 disease susceptibility and disease severity, respectively. The small sample size of this study may lessen the likelihood that the association found is real, but it could still be true. Further study with a larger cohort is required to confirm these findings.

Anti-Inflammatory Effects and Decreased Formation of Neutrophil Extracellular Traps by Enoxaparin in COVID-19 Patients.

Neutrophil Extracellular Traps (NETs) are a contributing factor of vascular thrombosis and alveolar damage in COVID-19 patients. As enoxaparin is currently used to inhibit vascular thrombosis, this study aimed to investigate whether enoxaparin also reduced inflammation and NETs in COVID-19 patients. Patients with COVID-19 infection were classified into three groups: mild, moderate, and severe (n = 10 for all groups). Plasma was collected from patients and healthy donors (n = 10). Neutrophils isolated from healthy controls were incubated with COVID-19 or healthy plasma, and with or without enoxaparin pretreatment in vitro. Neutrophils and plasma isolated from patients treated with enoxaparin were also investigated. The levels of inflammatory cytokines and NET products such as dsDNA, NE, MPO−DNA and Histone−DNA complexes in plasma and supernatants were measured using immunofluorescence staining and ELISA kits. The expression of inflammatory signaling genes by neutrophils (RELA, SYK, ERK and PKC) was measured using real-time qPCR. The levels of NET products were elevated in the plasma of COVID-19 patients, particularly in the severe group (p < 0.01). Moreover, plasma from the severe group enhanced NET formation (p < 0.01) from neutrophils in vitro. Enoxaparin pretreatment in vitro decreased plasma-induced NETs in a dose-dependent manner and down-regulated the expression of inflammatory genes (p < 0.05). Patients treated with prophylactic enoxaparin showed lower inflammatory cytokine levels and expression of inflammatory genes (p < 0.05). Increased NETs were associated with the severity of COVID-19 infection, particularly in patients with severe pneumonia, and could be used as biomarkers to assess disease severity. Enoxaparin pretreatment inhibited NETs and reduced the expression of inflammatory cytokines, and these effects mostly persisted in patients treated with prophylactic enoxaparin.

Short-term immune response after inactivated SARS-CoV-2 (CoronaVac®, Sinovac) and ChAdOx1 nCoV-19 (Vaxzevria®, Oxford-AstraZeneca) vaccinations in health care workers.

BACKGROUND: Inactivated SARS-CoV-2 (CoronaVac®, Sinovac, or SV) and ChAdOx1 nCoV-19 (Vaxzevria®, Oxford-Astra Zeneca, or AZ) vaccines have been administered to the health care workers (HCWs). OBJECTIVE: To determine the short-term immune response after the SV and AZ vaccinations in HCWs. METHODS: In this prospective cohort study, HCWs who completed a 2-dose regimen of the SV or AZ were included. Immune response was evaluated by surrogate viral neutralization test (sVNT) and anti-SARS-CoV-2 total antibody. Blood samples were analyzed at 4 and 12 weeks after the complete vaccination. The primary outcome was the seroconversion rate at 4-weeks after complete immunization. RESULTS: Overall, 185 HCWs with a median (IQR) age of 40.5 (30.3-55.8) years (94 HCWs in the SV group and 91 in the AZ group) were included. At 4 weeks after completing the SV vaccination, 60.6% (95%CI: 50.0-70.6%) had seroconversion evaluated by sVNT (≥ 68% inhibition), comparable to the patients recovered from mild COVID-19 infection (69.0%), with a rapid reduction to 12.2% (95%CI: 6.3-20.8) at 12 weeks. In contrast, 85.7% (95%CI: 76.8-92.2%) HCWs who completed two doses of the AZ for 4 weeks had seroconversion, comparable to the COVID-19 pneumonia patients (92.5%), with a reduction to 39.2% (95%CI: 28.4-50.9%) at 12 weeks. When using the anti-SARS-CoV-2 total antibody level (≥ 132 U/ml) criteria, only 71.3% HCWs in the SV group had seroconversion, compared to 100% in the AZ group at 4 weeks. CONCLUSIONS: A rapid decline of short-term immune response in the HCWs after the SV vaccination indicates the need for a vaccine booster, particularly during the ongoing spreading of the SARS-CoV-2 variants of concern.

A case of successful treatment of severe COVID-19 pneumonia with favipiravir and tocilizumab in post-kidney transplant recipient.

We report a case of COVID-19 in kidney transplant patient in Thailand. A 58-year-old 2 years post-kidney transplant recipient, with maintenance immunosuppression of tacrolimus, mycophenolate mofetil (MMF), and prednisolone, presented with acute diarrhea which followed by fever on day 12. Symptoms of pneumonia together with lymphopenia from complete blood count were developed on day 7 after onset of fever with the x-ray finding of bilateral multifocal patchy infiltration. COVID-19 infection has been confirmed by reverse real-time polymerase chain reaction (PCR) in nasal swab as well as found in stool. Darunavir together with ritonavir, hydroxychloroquine, azithromycin, and favipiravir was initiated on the first day of admission at primary hospital. Patient has been transferred to our hospital on day 2 of admission in which tacrolimus together with MMF was discontinued. High-flow nasal cannula oxygen therapy was required on days 4-5 of hospitalization. Tocilizumab was administered after rising of serum IL-6 level. Symptoms of pneumonia were improved in which no oxygen treatment required from day 10 of hospitalization. Drug interaction between tacrolimus and anti-viral treatment leads to severely high level of tacrolimus which caused reversible acute kidney injury (AKI) after supportive treatment.

In Vitro Susceptibility of Thai Pythium insidiosum Isolates to Antibacterial Agents.

Human pythiosis is a life-threatening human disease caused by Pythium insidiosum In Thailand, vascular pythiosis is the most common form and carries a mortality rate of 10 to 40%, despite aggressive treatment with radical surgery, antifungal agents, and immunotherapy. Itraconazole and terbinafine have been the mainstay of treatment, until recently, based on case report data showing potential synergistic effects against Brazilian P. insidiosum isolates. However, the synergistic effects of itraconazole and terbinafine against Thai P. insidiosum isolates were not observed. This study tested the in vitro susceptibilities of 27 Thai human P. insidiosum isolates (clade II, n = 17; clade IV, n = 10), 12 Thai environmental P. insidiosum isolates (clade II, n = 4; clade IV, n = 8), and 11 non-Thai animal P. insidiosum isolates (clade I, n = 9; clade II, n = 2) to antibiotics in eight antibacterial classes to evaluate alternative effective treatments. Tetracycline and macrolide antibiotics demonstrated in vitro activity against Thai P. insidiosum isolates, with doxycycline MICs (1 to 16 µg/ml), minocycline MICs (1 to 4 µg/ml), tigecycline MICs (1 to 4 µg/ml), azithromycin MICs (1 to 16 µg/ml), and clarithromycin MICs (0.125 to 8 µg/ml) being the lowest, on average. Synergistic effects of tetracyclines and macrolides were also observed.

Clinical outcomes in ocular pythiosis patients treated with a combination therapy protocol in Thailand: A prospective study.

Ocular pythiosis is the second most common form of human pythiosis, and the rates of evisceration/enucleation in Thailand are 55-79%. This prospective study was conducted to evaluate treatment outcomes of the combination therapy protocol and the potential use of serum (1→3)-ß-glucan (BG) and Pythium insidiosum-specific antibody (Pi-Ab) as an aid to diagnosis and monitoring of ocular pythiosis. Thirty patients were enrolled in the study and 14 (non-globe salvage) required evisceration/enucleation. The globe salvage group was significantly younger, and first ocular surgeries were performed significantly sooner than in the non-globe salvage group. Serum BG and Pi-Ab levels were similar among the 2 groups over time. In vitro susceptibility testing of antifungal agents revealed relatively high minimum inhibitory concentrations and lack of synergistic effect. Serum BG and Pi-Ab would not be useful in diagnosis and monitoring of ocular pythiosis. Until effective antimicrobial agents are discovered, ocular surgeries are still the mainstay therapy in Thailand.

The first human case report of molecularly confirmed co-infection of Brucella melitensis and Coxiella burnetii: A case report.

Co-infection with Brucella melitensis and Coxiella burnetii has been rarely reported. To date, there are only two co-infection case reports from Croatia and China which diagnosed the infections mainly through the use of serological tests. In this report, we present the first case of molecularly confirmed B. melitensis bacteremia and C. burnetii spondylodiscitis co-infection in a goat dairy farmer who presented with lumbosacral spondylodiscitis and bilateral psoas abscesses. From the blood culture, B. melitensis was identified by using 16S rRNA gene sequencing and specific PCR. Lumbar bone tissue was found to be positive for C. burnetii using multiplex real-time PCR and was confirmed with a positive result from conventional PCR which detected the infection through the identification of the IS1111 gene. The patient's condition improved after decompressive laminectomy was performed and administration of antibiotics regimen: intravenous gentamicin, oral rifampicin, and oral doxycycline. From our case, it is important to raise awareness of this underreported co-infection with multiple zoonotic diseases, especially Q fever and brucellosis, which share the same exposure risk. Moreover, we also emphasize the use of advanced molecular techniques to improve the diagnostic efficiency and reduce the use of time-consuming procedures among patients who are continuously exposed to such risk factors in areas with high seroprevalence of these zoonotic diseases.

Ex vivo observation of Pythium insidiosum-antigen treated neutrophils on three Pythium insidiosum strains isolated from vascular pythiosis patients.

The mechanisms of Pythium insidiosum-antigen (PIA) immunotherapy activating a patient's immune system are unknown. We evaluated the interleukin-8 (IL-8) serum levels during P. insidiosum infection and after vaccination with PIA in vascular pythiosis cases. Furthermore, we studied the anti-P. insidiosum activity of neutrophils stimulated with various concentrations of PIA ex vivo in 3 strains of P. insidiosum isolated from vascular pythiosis patients. IL-8 serum levels were evaluated using the ELISA technique. We assessed the effect of PIA-stimulated neutrophils on the viability of zoospores using MTT assay, visualized neutrophil extracellular trap (NET) formation via microscopy, and measured the levels of double-stranded DNA (dsDNA) using PicoGreen dsDNA quantitation assay in 3 strains of P. insidiosum isolated from vascular pythiosis patients. Serum levels of IL-8 gradually lowered from the early to the end phases of vaccination with PIA among the surviving group of vascular pythiosis cases. Neutrophils stimulated with 0.01 µg/ml PIA reduced zoospore viability significantly compared to PIA-unstimulated neutrophils for strain 1 and strain 3 (p < .05). Neutrophils stimulated with 0.01, 0.1, 1, and 10 µg/ml PIA exhibited significantly lower zoospore viability than PIA-unstimulated neutrophils for strain 2 (p < .05). IL-8 can be used as a biomarker for monitoring vascular pythiosis cases treated with the PIA vaccine. Also, anti-P. insidiosum activity of PIA-stimulated neutrophils was probably due to the disruption of cellular activity in zoospores rather than the mechanisms based on the formation of NETs.

Needs assessment of a pythiosis continuing professional development program.

BACKGROUND: Pythiosis is a rare disease with high mortality, with over 94% of cases reported from Thailand and India. Prompt diagnosis and surgery improves patient outcomes. Therefore, continuing professional development (CPD) is essential for early recognition. However, a needs assessment related to a pythiosis CPD program has not been performed. OBJECTIVES: We conducted a needs assessment to develop a pythiosis CPD program. PATIENTS/METHODS: We conducted a survey study with 267 King Chulalongkorn Memorial Hospital residents (141 internal medicine (IM) residents and 126 surgery residents). A 30-item survey consisting of a knowledge assessment, demographic section, and an attitudes portion was distributed both electronically and via paper. The data was analyzed with descriptive and inferential statistics. RESULTS: Sixty-seven percent completed the survey (110/141 IM residents, 70/126 surgery residents). The mean score [95% confidence interval] on the knowledge assessment was 41.67% [39.64%-43.69%] across all objectives. The three domains with the highest scores were pythiosis risk factors (67.22% correct), microbiologic characteristics (50.83%), and radiographic interpretation (50.56%). The three domains with the lowest scores were laboratory investigation (15.00%), epidemiology (29.17%), and symptomatology (30.83%). Most participants noted that the program should be online with both synchronous and asynchronous sessions, with a preferred length of 60-90 minutes per session. CONCLUSION: The pythiosis CPD program should emphasize education regarding symptomatology, laboratory investigation, and epidemiology, all of which are critical for the early detection of pythiosis to decrease mortality from this devastating disease. Most respondents felt this program was necessary and should be implemented in a virtual blended format.

First case series and literature review of coronavirus disease 2019 (COVID-19) associated pulmonary tuberculosis in Southeast Asia: Challenges and opportunities.

BACKGROUND: Subclinical tuberculosis (TB) is accidentally detected by radiologic and microbiologic findings. Transmission by those with subclinical TB could delay prevention effort. However, our study demonstrated positive aspect of COVID-19 outbreak as it could allow subclinical TB to be detected faster through a chest X-Ray (CXR). METHODS: This cross-sectional cohort study aimed to report demographics, comorbidities, and outcomes related to early detection of TB among COVID-19 patients, and to elaborate the association between SARS-CoV-2 and pulmonary TB. Data of patients with SARS-CoV-2 co-infection with Mycobacterium tuberculosis (MTB) diagnosed between March 2020 - March 2022 was collected. RESULTS: Out of 12,275 COVID-19 patients, 26 were definitively diagnosed with MTB infection (mean age 48.16 ± 20.17 years). All cases that had suspicious CXR that were not typical for COVID-19, were tested for MTB. On average, pulmonary TB was diagnosed after admission 5(3-10) days, the treatment initiation period was 3(1-5) days from the TB diagnosis. CONCLUSIONS: This suggests an early detection of tuberculosis among COVID-19 patients by quicker screening CXR and sputum comparing to previous symptom guided screening. Thereby reducing the chance of TB transmission demonstrated during COVID-19 pandemic. So, clinicians should be aware of pulmonary tuberculosis in COVID-19 patients with atypical radiologic findings.

Telepharmacy during home isolation: drug-related problems and pharmaceutical care in COVID-19 patients receiving antiviral therapy in Thailand.

BACKGROUND: Home isolation has been proposed for coronavirus disease 2019 (COVID-19) patients with mild symptoms to avoid hospital overcrowding. This study aimed to describe the drug-related problems (DRPs) and the pharmaceutical care of home-isolating COVID-19 patients in Thailand. METHODS: Our cross-sectional study was undertaken from July 1 to September 30, 2021, at the King Chulalongkorn Memorial Hospital, Thailand. Patients who were ≥ 18 years old, were diagnosed with mild COVID-19 by real-time polymerase chain reaction (RT-PCR), and were able to isolate at home while receiving an antiviral agent and standard symptomatic treatment were enrolled. Infectious disease pharmacists provided a telepharmacy service on days 1 and 3 after the COVID-19 diagnosis. RESULTS: A total of 197 patients met the study criteria. Their median age was 45 years, and their most common underlying disease was hypertension (44.29%). All patients exhibited excellent anti-COVID-19 drug adherence. We identified 125 DRPs, including adverse reactions (68%), and the unnecessary use of products (62.40%). Moreover, 91 patients (46.19%) reported the use of supplements or herbs, with vitamin C being the main supplement (37.36%). Pharmacists provided 36 recommendations and received 33 questions from COVID-19 patients. CONCLUSIONS: Our study demonstrates that telepharmacy is an essential service for detecting and preventing DRPs in home-isolating COVID-19 patients.

The In Vitro Efficacy of Activated Charcoal in Fecal Ceftriaxone Adsorption among Patients Who Received Intravenous Ceftriaxone.

Broad-spectrum antibiotics can kill both pathogens and gut microbiota. Reducing exposure to excess intestinal antibiotics could theoretically protect gut microbiota homeostasis. Recently, engineered charcoals, gel microparticles, and resin beads have demonstrated efficacy in intestinal antibiotic adsorption in animal studies. We report the first in vitro study evaluating human fecal antibiotic adsorption efficacy of conventional activated charcoal (AC). We collected fecal samples from eight patients who received intravenous (IV) ceftriaxone after admission to King Chulalongkorn Memorial Hospital, Thailand, during January−March 2020. Fecal ceftriaxone was measured by indirect competitive enzyme-linked immunoassays. Three different doses of AC were mixed with fecal samples under a specified protocol. The geometric mean reduction in fecal ceftriaxone concentration when mixed with AC 30 mg/g feces was 0.53 (95% CI 0.33−0.85, p-value < 0.001), meaning 47% adsorption efficacy. Increased adsorption was found with higher doses, 71% and 87% for AC 150 and 500 mg/g feces, respectively. In conclusion, the usual food-poisoning-care dose of conventional AC, 30 mg/g feces, demonstrated dose-dependent and significant fecal ceftriaxone adsorption. Conventional oral AC might be a pragmatic and inexpensive option for the protection of gut microbiota in patients receiving IV ceftriaxone. However, in vivo studies and microbiome analysis are needed for further evidence.

Gas chromatography-flame ionization detector for sweat based COVID-19 screening.

Simple approach for rapid screening of corona virus disease 2019 (COVID-19) has been developed. This applied gas chromatography-flame ionization detector (GC-FID) analyzing the potential compound marker in sweat samples obtained from COVID-19 positive and negative volunteers in Bangkok, Thailand. The samples were collected by using cotton rods for 15 min, heated at 90 °C for 5 min, and the volatile compounds in the headspace (HS) were injected (5.00 mL) at 150 °C and separated within 13.7 min. The marker peak was tentatively identified as p-cymene by the authentic standard injection and comparison with the GC-mass spectrometry (GC-MS) and comprehensive two-dimensional GC (GC × GC)-MS analysis. Possible mechanisms for the presence of p-cymene were proposed. The marker peak area thresholds were then varied and optimized via construction of the receiver operating characteristic (ROC) curve. With the optimum threshold, the established method offered the accuracy, sensitivity and specificity of 96 %. This method was insignificantly affected (p-value >0.05) by genders, body mass indices, ages, and use of deodorants as well as the p-cymene containing food. However, the performance could be affected by the population with personal hygiene or experiencing the microbiomes producing p-cymene.

Simultaneous Detection of Omicron and Other SARS-CoV-2 Variants by Multiplex PCR MassARRAY Technology.

The rapid emergence of SARS-CoV-2 variants with high severity and transmutability adds further urgency for rapid and multiplex molecular testing to identify the variants. A nucleotide matrix-assisted laser-desorption-ionization time-of-flight mass spectrophotometry (MALDI-TOF MS)-based assay was developed (called point mutation array, PMA) to identify four major SARS-CoV-2 variants of concern (VOCs) including Alpha, Beta, Delta, and Omicron (namely PMA-ABDO) and differentiate Omicron subvariant (namely PMA-Omicron). PMA-ABDO and PMA-Omicron consist of 24 and 28 mutation sites of the spike gene. Both PMA panels specifically identified VOCs with as low as 10 viral copies/ µl. The panel has shown a 100% concordant with the Next Generation Sequencing (NGS) results testing on 256 clinical specimens with real-time PCR cycle threshold (Ct) values less than 26. It showed a higher sensitivity over NGS; 25/28 samples were positive by PMA but not NGS in the clinical samples with PCR Ct higher than 26. Due to the mass of nucleotide used to differentiate between wild-type and mutation strains, the co-infection or recombination of multiple variants can be determined by the PMA method. This method is flexible in adding a new primer set to identify a new emerging mutation site among the current circulating VOCs and the turnaround time is less than 8 hours. However, the spike gene sequencing or NGS retains the advantage of detecting newly emerged variants.

Simultaneous detection of omicron and other SARS-CoV-2 variants by multiplex PCR MassARRAY technology.

The rapid emergence of SARS-CoV-2 variants with high severity and transmutability adds further urgency for rapid and multiplex molecular testing to identify the variants. A nucleotide matrix-assisted laser-desorption-ionization time-of-flight mass spectrophotometry (MALDI-TOF MS)-based assay was developed (called point mutation array, PMA) to identify four major SARS-CoV-2 variants of concern (VOCs) including Alpha, Beta, Delta, and Omicron (namely PMA-ABDO) and differentiate Omicron subvariant (namely PMA-Omicron). PMA-ABDO and PMA-Omicron consist of 24 and 28 mutation sites of the spike gene. Both PMA panels specifically identified VOCs with as low as 10 viral copies/µl. The panel has shown a 100% concordant with the Next Generation Sequencing (NGS) results testing on 256 clinical specimens with real-time PCR cycle threshold (Ct) values less than 26. It showed a higher sensitivity over NGS; 25/28 samples were positive by PMA but not NGS in the clinical samples with PCR Ct higher than 26. Due to the mass of nucleotide used to differentiate between wild-type and mutation strains, the co-infection or recombination of multiple variants can be determined by the PMA method. This method is flexible in adding a new primer set to identify a new emerging mutation site among the current circulating VOCs and the turnaround time is less than 8 h. However, the spike gene sequencing or NGS retains the advantage of detecting newly emerged variants.

Ribavirin treatment for respiratory syncytial virus infection in patients with haematologic malignancy and haematopoietic stem cell transplant recipients: a systematic review and meta-analysis.

BACKGROUND: Ribavirin use for respiratory syncytial virus (RSV) infection in patients with haematologic malignancies (HM) and haematopoietic stem cell transplant (HSCT) recipients remains controversial. OBJECTIVES: To summarize the current evidence of ribavirin treatment in association with mortality and progression to lower respiratory tract infection (LRTI) among patients with HM/HSCT with RSV infection. DATA SOURCES: MEDLINE, Embase, and the Institute for Scientific Information Web of Science. STUDY ELIGIBILITY CRITERIA: Randomized controlled trials and observational studies investigating the effects of ribavirin, compared with treatment without ribavirin, for RSV infection. PARTICIPANTS: Patients with HM/HSCT. INTERVENTIONS: Ribavirin versus no ribavirin. ASSESSMENT OF RISK OF BIAS: The risk of bias in non-randomized studies of exposure (ROBIN-E). METHODS OF DATA SYNTHESIS: The random-effects model was used to calculate the pooled OR (pOR) with 95% CI for the pooled effect estimates of ribavirin benefits. Grading of recommendation assessment, development, and evaluation was used to evaluate the certainty of evidence. RESULTS: One randomized controlled trial and 14 observational studies were included, representing 1125 patients with HM/HSCT. Ribavirin use was not associated with lower all-cause or RSV-associated mortality with pORs [95% CI] of 0.81 [0.40, 1.66], I2 = 55% (low certainty of evidence) and 0.48 [0.11, 2.15], I2 = 64% (very low certainty of evidence), respectively. In subgroup analyses, ribavirin use was associated with lower mortality in patients with HM/HSCT with LRTI with pOR [95% CI] of 0.19 [0.07, 0.51], I2 = 0% (moderate certainty of evidence). In subgroup analyses among studies providing adjusted OR, ribavirin use was associated with lower all-cause mortality with pOR of 0.41 [0.23, 0.74], I2 = 0% (moderate certainty of evidence). In addition, aerosolized ribavirin was associated with lower progression to LRTI with pOR [95% CI] of 0.27 [0.09, 0.80], I2 = 71% (low certainty of evidence). CONCLUSIONS: Ribavirin may be a reasonable option to treat RSV in patients with HM/HSCT in the absence of other effective antiviral agents.

Attenuated immunogenicity of SARS-CoV-2 vaccines and risk factors in stem cell transplant recipients: a meta-analysis.

Immunogenicity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is diminished in hematopoietic stem cell transplant (HSCT) recipients. To summarize current evidence and identify risk factors for attenuated responses, 5 electronic databases were searched since database inceptions through 12 January 2023 for studies reporting humoral and/or cellular immunogenicity of SARS-CoV-2 vaccination in the HSCT population. Using descriptive statistics and random-effects models, extracted numbers of responders and pooled odds ratios (pORs) with 95% confidence intervals (CIs) for risk factors of negative immune responses were analyzed (PROSPERO: CRD42021277109). From 61 studies with 5906 HSCT recipients, after 1, 2, and 3 doses of messenger RNA (mRNA) SARS-CoV-2 vaccines, the mean antispike antibody seropositivity rates (95% CI) were 38% (19-62), 81% (77-84), and 80% (75-84); neutralizing antibody seropositivity rates were 52% (40-64), 71% (54-83), and 78% (61-89); and cellular immune response rates were 52% (39-64), 66% (51-79), and 72% (52-86). After 2 vaccine doses, risk factors (pOR; 95% CI) associated with antispike seronegativity were male recipients (0.63; 0.49-0.83), recent rituximab exposure (0.09; 0.03-0.21), haploidentical allografts (0.46; 0.22-0.95), <24 months from HSCT (0.25; 0.07-0.89), lymphopenia (0.18; 0.13-0.24), hypogammaglobulinemia (0.23; 0.10-0.55), concomitant chemotherapy (0.48; 0.29-0.78) and immunosuppression (0.18; 0.13-0.25). Complete remission of underlying hematologic malignancy (2.55; 1.05-6.17) and myeloablative conditioning (1.72; 1.30-2.28) compared with reduced-intensity conditioning were associated with antispike seropositivity. Ongoing immunosuppression (0.31; 0.10-0.99) was associated with poor cellular immunogenicity. In conclusion, attenuated humoral and cellular immune responses to mRNA SARS-CoV-2 vaccination are associated with several risk factors among HSCT recipients. Optimizing individualized vaccination and developing alternative COVID-19 prevention strategies are warranted.