Infectious diseases (London, England)最新文献

Purpose: Acute undifferentiated febrile illness (AUFI) and acute encephalitis syndrome (AES) continue to be major public health concerns, particularly in rural areas with limited healthcare facility. We investigated the aetiological agents responsible for seasonal sporadic AUFI and AES cases in Northern India.

Method: The study included 4200 patient samples (April 2022 to March 2024), fulfilling the AUFI or AES case definition. Clinical samples were tested for IgM antibodies against dengue, chikungunya, Japanese encephalitis, scrub typhus, and leptospirosis. Further, Leptospira IgM ELISA positives (n = 79) were also tested by microscopic agglutination test (MAT) assay.

Results: In AUFI cases, scrub typhus was the predominant bacterial aetiology (24.6%, 593/2407) followed by leptospirosis (12.4%, 266/2151). Dengue (23.0%, 321/1398) was the leading cause among viral aetiologies. Similarly, among AES cases, scrub typhus (36% in cerebrospinal fluid and 34.3% in serum) remained the most common bacterial aetiology followed by leptospirosis (5.42%, 11/203). Whereas, chikungunya was the predominant viral cause (5.4%, 17/314) behind AES cases. Further, using MAT assay, 7.6% (6/79) of the AUFI samples tested positive for leptospirosis. The prevalent serogroups identified included L. interrogans serovars Australis, Pomona, Hebdomadis, Pyrogenes and Djasiman, and L. borgpetersnii serovar Tarassovi. Housewives constituted the primary risk group for leptospirosis infection, followed by individuals engaged in various farming practices.

Conclusion: This study identifies scrub typhus as the predominant and leptospirosis as the second most common infection in sporadic cases of AUFI and AES. Therefore, continuous monitoring of changing aetiologies is crucial for the effective implementation of targeted control and preventive measures for neglected tropical diseases.

Background: Congenital Cytomegalovirus (cCMV) is the most common prenatal infection and the main infectious cause of neurodevelopmental abnormalities in developed countries. Long-term neuropsychological outcome of cCMV infection is yet not well understood, and follow-up studies on adults screened for CMV at birth are few. The aim of this study was to investigate self-reported executive functioning (EF) in adults with cCMV infection in relation to uninfected controls.

Method: All individuals from a universal newborn CMV screening study conducted in Southern Sweden and sampled 1977-85, was invited to participate in a follow-up study. 45/71 individuals (63%) with cCMV infection and 25/46 controls (54%) were enrolled. Participants were aged 34-43 years. Neurological symptoms and neuropsychiatric disabilities were documented through written reports from the original study and a semi-structured study protocol. Executive functioning was evaluated with BRIEF-A (questionnaire).

Results: No statistically significant differences were found between groups in self-reported executive functioning, although greater variability in outcomes was observed in the cCMV group.

Conclusion: Everyday executive functioning might not be affected at the group level in adults with cCMV infection or may not be adequately captured through self-reports alone. The variability in executive functioning results suggests that individuals with cCMV infection represent a more heterogeneous group compared to the controls.

Background: This study aimed to validate the septic arthritis diagnosis using International Classification of Diseases (ICD)-10 codes against the Newman criteria. Additionally, the study presents disease characteristics and compares subgroups.

Methods: 475 patients with an ICD-10 code for septic arthritis were identified at a university (n = 265) and a county (n = 167) hospital in West Sweden between 2016 and 2019. Medical records were analysed for adherence to the Newman criteria. Clinical data and culture results were compared between the university hospital and the county hospital, as well as between subgroups categorised by the pathogenetic route of infection, including direct inoculation and haematogenous spread infection.

Results: 91% of the patients fulfilled the Newman criteria (52% positive for synovial culture or PCR, 24% positive culture from blood or elsewhere, and 24% with radiological evidence or turbid synovial fluid). The patient population was predominantly male (62%), with a median age of 69 years, and the knee was the most commonly affected joint (39%). Staphylococcus aureus emerged as the predominant pathogen across all patient groups. 80% had a haematogenous spread septic arthritis, while 20% resulted from direct inoculation. In the haematogenous spread groups, patients were older, with fewer males, but higher CRP levels compared to those in the direct inoculation group.

Conclusion: ICD-10 codes for septic arthritis have a positive predictive value of 91% in relation to the Newman criteria in Swedish hospital care, making the utilisation of ICD-10 codes a reliable data source for future epidemiological studies.

Background: The relationship between the initial viral load in respiratory specimens and the severity of COVID-19 is not fully elucidated. Studies on the impact of patient age on the SARS-CoV-2 load have yielded divergent results.

Objective: We aimed to investigate the impact of viral load in COVID-19.

Methods: We mined a dataset of 259,511 SARS-CoV-2-infected individuals 0-105 years old in which virus RNA was quantified in nasopharyngeal swabs (viral load) using PCR at first healthcare contact. Subjects were stratified by vaccination and pandemic variant wave. Severity was assessed by hospital admission or death. Multivariable models analysed the influence of age on viral load, and viral load on severity.

Results: Among non-vaccinated (n = 140,905), viral loads of SARS-CoV-2 were lowest in children 1-9 years old and highest in infants (<1 year old) and in subjects 70-105 years, with similar results across pandemic waves and in vaccinated individuals. High viral load (≥9log₁₀viral RNA copies/swab) associated with elevated risk of hospital admission across age groups. In adults (20-69 years old), mortality was largely confined to those with high viral load (odds ratio [OR] 5.3, 95%CI 3.6-7.3). Among subjects ≥ 70 years old, deaths occurred across viral loads but were more frequent at high viral loads (OR 2.2, 95% CI 1.9-2.6). High viral load associated with hospitalisation and mortality also in vaccinated individuals (n = 118,606).

Conclusions: This study identified high viral load at first sampling as a predictor of severe infection and/or death across age groups of SARS-CoV-2-infected patients.

Background: The natural history of HBV infection is highly heterogeneous. Failure to clear the virus during the acute phase of infection allows for viral persistence and progression to chronicity. Investigating the immune mechanisms involved in this process is crucial for effectively managing infection outcome. HLA-Ib molecules (HLA-G, HLA-E and HLA-F) play a critical role in regulating the immune response.

Objectives: primary objective: we investigate the potential impact of functional polymorphisms in HLA-F*01:03 (rs1736924), HLA-E*01:01/01:03 (rs1264457), and two selected HLA-G polymorphisms in Exon 2 (+292 A > T (rs41551813) and +372 G > A (rs1130355)) on HBV infection outcome. Secondary objective: we evaluate the expression of soluble HLA-E in our cohort.

Methods: We evaluated these polymorphisms in a cohort of 200 patients with chronic HBV infection and 100 individuals who spontaneously resolved the infection, using SSP-PCR and Sanger sequencing. Additionally, we measured soluble HLA-E (sHLA-E) levels using ELISA.

Results: Our results showed a significant association of HLA-G (rs41551813) and HLA-E (rs1264457) polymorphisms with HBV infection outcome, where carriers of the A allele in both HLA-G (rs41551813) and HLA-E (rs1264457) had a significantly higher likelihood of spontaneous HBV clearance (all p < 0.01). Furthermore, we demonstrate that elevated sHLA-E expression favours HBV persistence. Additionally, our findings has revealed that the HLA-G + 292 A > T polymorphism (rs41551813) is associated with regulation of sHLA-G expression. Haplotype analysis further identified the 'TAAA' haplotype as linked to spontaneous HBV clearance.

Conclusion: this study demonstrates, for the first time, the critical role of HLA-Ib on HBV infection outcome, providing insights for potential therapeutic interventions.

Background: Presence of a prosthetic joint entails a life-long risk of haematogenous periprosthetic joint infection (hPJI) during bacteraemia. For bacteraemia with Staphylococcus aureus the hPJI frequency has been described to be up to 40% and for streptococci up to 20%, with large variation among reported frequencies.

Objectives: We aimed to investigate the hPJI frequency from bacteraemia with virulent gram-positive cocci in patients with hip and/or knee prosthesis.

Methods: A population and register based approach was used. Through cross-matching of blood cultures positive for virulent gram-positive cocci and data from the Swedish Arthroplasty Register, patients with at least one prosthesis in place during bacteraemia were identified. Medical records were reviewed if patients had concordant microbiological cultures in blood and synovial fluid, tissue or bone, to determine if hPJI was present. Absence of concordant cultures was interpreted as absence of hPJI.

Results: Of all 2392 episodes of bacteraemia identified during the study period, 143 (6%) caused at least one hPJI. The highest frequency of hPJI was observed for S. aureus (9.6%) and Streptococcus agalactiae (9.3%). Increasing number of prostheses in place, male sex and lower age were independently associated with hPJI. Bacteraemia with other species than S. aureus or S. agalactiae was associated with a lower hPJI risk.

Conclusion: The observational risk of hPJI from bacteraemia with virulent gram-positive cocci was much lower than in previous reports, especially for S. aureus, with an hPJI frequency of 9.6%.

Background: The study aimed to describe all diagnosed cases of Legionnaire's disease (LD) in south Sweden, regarding incidence, patient characteristics, diagnostics, outcomes, and infection control investigations.

Methods: This population-based retrospective study was conducted in Skåne, on patients with LD between 2011-2021. Inclusion criteria were positive polymerase chain reaction (PCR) for L. pneumophila/Legionella spp. or a positive urinary antigen test (UAT), combined with a clinical presentation consistent with Legionella infection and radiological evidence of pulmonary infiltrates.

Results: A total of 280 patients met the inclusion criteria, with a mean incidence of 2.00 per 100,000 person-years (95% CI: 1.23-2.78). Empiric treatment covering Legionella was administered in 15% of cases. Mortality rates were 13%, 15% and 23% at 30-, 90- and 365 days, respectively. UAT was performed in 88% of patients, with a 66% positivity rate. Lower respiratory tract PCR was performed in 76% of patients with a 90% positivity rate. Bacterial culture was positive in 43% of cases. Out of these, L. pneumophila serogroup 1 was most common (58%), though a significant proportion were serogroups 2-14 (30%), which are not generally detected by UAT. Genetic matches between environmental and patient strains were established in 5% of cases.

Conclusion: Legionnaires' disease in Skåne is an uncommon but clinically significant condition. Few patients received appropriate empiric antibiotic treatment. Reliance on UAT alone is insufficient for establishing diagnosis, and species-specific PCR, particularly from lower respiratory samples, enhances detection. Environmental investigations frequently identified Legionella in suspected settings; however, a definitive source of infection was rarely established.