A recent Infectious Disease digest,
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Study Type: Retrospective quasi-experimental study

Key Question: Is early discontinuation of empirical antibiotics within 72 hours safe in paediatric haploidentical haematopoietic cell transplant recipients with febrile neutropenia?

Key Findings:

• Implementation of early discontinuation guidelines reduced median antibiotic duration by 8 days (p<0.01) compared to pre-implementation practice
• No significant differences in bloodstream infection rates, ICU admission, or mortality between groups
• DOOR-RADAR analysis showed 70% probability (95% CI 61-78%) of more favourable outcomes with early discontinuation strategy

Clinical Relevance: This supports consideration of shorter empirical antibiotic courses in high-risk paediatric transplant patients with febrile neutropenia, potentially reducing antimicrobial resistance and toxicity without compromising safety in UK paediatric oncology centres.

Limitations: Single-centre retrospective design limits generalisability and requires validation in larger prospective multicentre trials.

Study Type: Clinical review/commentary

Key Question: How can clinicians manage hepatitis B virus (HBV) infection and reactivation risks when switching HIV patients to tenofovir-sparing antiretroviral therapy or PrEP regimens?

Key Findings:

• Tenofovir-sparing HIV regimens increase risk of new HBV infection and reactivation due to reduced anti-HBV activity
• Risk magnitude varies by patient's baseline HBV serology status
• Risks are preventable through systematic HBV screening, vaccination, and post-switch monitoring protocols

Clinical Relevance: Provides practical guidance for UK HIV clinicians increasingly using newer tenofovir-sparing regimens, emphasising need to balance HIV treatment convenience against HBV co-infection risks in routine clinical practice.

Limitations: As a narrative review, does not provide quantitative risk estimates or comparative effectiveness data for proposed mitigation strategies.

Study Type: Economic modelling study using microsimulation (CEPAC-I model)

Key Question: What is the cost-effectiveness of improved cryptococcal meningitis diagnostics and treatment strategies for HIV patients with positive serum CrAg in Malawi?

Key Findings:

• Improved access to liposomal amphotericin B/flucytosine/fluconazole increased 1-year survival by 2.2% with an ICER of US$140/QALY compared to current care (70% baseline survival)
• Combined semi-quantitative CrAg testing with confirmatory lumbar puncture plus optimised treatment achieved 6.0% survival improvement with ICER of US$380/QALY
• Both strategies remained cost-effective at established thresholds (US$150-600/QALY) for low-resource settings

Clinical Relevance: This provides economic justification for UK-funded global health programmes to support improved cryptococcal diagnostics and first-line treatment access in sub-Saharan Africa, where CM remains a leading cause of HIV-related mortality.

Limitations: Results depend heavily on test uptake rates and diagnostic performance characteristics, which may vary in real-world implementation.

Study Type: Phase IV open-label clinical trial

Key Question: Does liraglutide plus lifestyle counselling improve weight and cardiometabolic outcomes in people with HIV and obesity in rural South Africa?

Key Findings:

• 40 participants with HIV and BMI ≥30 kg/m² showed significant improvements after 12 weeks: 2.9% weight reduction, 5.6cm waist circumference decrease, and 0.3% HbA1c reduction
• Secondary benefits included improved depression scores, sleep quality, and psychological quality of life during treatment
• High acceptability with 95% completion rate, but weight and metabolic gains were lost after treatment discontinuation at 24 weeks

Clinical Relevance: First GLP-1 receptor agonist obesity trial in Southern African HIV populations demonstrates efficacy and acceptability, potentially informing treatment approaches for the growing obesity epidemic in HIV-positive patients in resource-limited settings.

Limitations: Open-label design without control group and small sample size limit generalisability of findings.

Study Type: Retrospective cohort study

Key Question: What is the association between CD4 cell counts and cancer-specific mortality in people with HIV and cancer?

Key Findings:

• Among 12,087 people with HIV and cancer, those with CD4 counts 0-49 cells/mm³ had significantly higher cancer-specific mortality compared to those with ≥200 cells/mm³ across multiple cancers, including prostate cancer (HR 3.98, 95% CI 1.56-10.15) and lung cancer (HR 1.69, 95% CI 1.33-2.14)
• For lung cancer specifically, 3-year cancer-specific mortality was 72% in severely immunosuppressed patients (CD4 0-49) versus 52% in those with CD4 ≥200 cells/mm³
• The effect was observed across both AIDS-defining cancers and solid tumours not traditionally associated with HIV

Clinical Relevance: This supports prioritising immune reconstitution in HIV-positive cancer patients, as maintaining higher CD4 counts may improve cancer outcomes even for non-AIDS-defining malignancies.

Limitations: Observational design cannot establish causality between low CD4 counts and increased cancer mortality.

Study Type: Multicentre prospective diagnostic accuracy study

Key Question: What is the diagnostic accuracy of the LyocartE MTB assay for tuberculosis detection using sputum and tongue swab specimens compared to established reference standards?

Key Findings:

• LyocartE on sputum achieved 95.2% sensitivity and 98.6% specificity against microbiological reference standard (689 participants)
• Tongue swab LyocartE showed 87.4% sensitivity and 99.7% specificity compared to sputum Xpert Ultra
• Strong correlation with Xpert Ultra cycle threshold values for both specimen types (sputum r=0.75, tongue swab r=0.56)

Clinical Relevance: This near-point-of-care assay could enable rapid TB diagnosis using non-invasive tongue swabs, particularly valuable for UK TB services managing vulnerable populations where sputum collection is challenging.

Limitations: Study conducted only in Chinese populations with presumptive TB, requiring validation in asymptomatic and paucibacillary cases before broader clinical implementation.

Study Type: Narrative review/clinical commentary

Key Question: What is the current evidence regarding infection risks associated with medical cannabis use?

Key Findings:

• Only one case report has definitively linked cannabis to infection using genome sequencing (Cryptococcus neoformans)
• Cannabis products lack uniform microbial testing standards across US states, with no validated safety thresholds
• Multiple case reports describe cannabis-associated fungal and bacterial infections, but causality remains largely unproven

Clinical Relevance: UK clinicians prescribing medical cannabis should be aware of potential infectious complications, though evidence is limited and regulatory frameworks differ between US and UK contexts.

Limitations: Review focuses on US regulatory landscape which may not directly apply to UK clinical practice and medical cannabis regulations.

Study Type: Outbreak investigation

Key Question: What caused a cluster of Wickerhamomyces anomalus bloodstream infections in Venezuelan hospitals during 2022-2023?

Key Findings:

• 110 bloodstream infections identified across 8 hospitals in 3 Venezuelan cities over 16 months
• 82/110 cases occurred in a single paediatric ICU in Caracas, predominantly affecting neonates
• Molecular genotyping confirmed clonal transmission with epidemiological clustering, indicating nosocomial spread

Clinical Relevance: This highlights the potential for emerging yeast species to cause significant nosocomial outbreaks in vulnerable populations, particularly relevant given increasing antifungal resistance concerns and the need for robust infection control in UK neonatal units.

Limitations: Limited details provided regarding specific infection control measures implemented or patient outcomes during the outbreak period.