Assessing infectiousness and the impact of effective treatment to guide isolation recommendations for people with pulmonary tuberculosis.

Determining the extent and duration of infectiousness of individuals with pulmonary tuberculosis (TB) is critical for various aspects of TB care, including decisions regarding isolation. Studies suggest considerable heterogeneity in infectiousness of people with pulmonary TB. Pre-treatment, measures of bacillary burden including sputum smear microscopy, culture time-to-positivity, and Xpert MTB/RIF cycle threshold (Ct) value, predict the risk of transmission to contacts. Index patients with smear negative disease pose lower infectious risk than those who have smear-positive disease, and household contact infection is more likely with index patients who have lower Xpert Ct values. Newer tools that enable detection of Mycobacterium tuberculosis complex (Mtb complex) from cough aerosol sampling and face mask sampling may be better predictors of contact infection risk. Clinical factors such as cough strength and frequency, and presence of cavitation on chest imaging, may also assist with risk prediction. Post-treatment, smear and culture status are poor predictors of infectiousness. While the exact duration of infectiousness post treatment initiation remains uncertain, data from human-to-guinea pig transmission studies and clinical studies suggest effective treatment results in a rapid decline in infectiousness, irrespective of smear or culture conversion. This is largely supported by early bactericidal activity and transcriptomic studies, and cough aerosol sampling studies, although a subset of patients may have persistent cough aerosol positivity. These findings can enable a more nuanced approach to isolation decision making, while further research studies are awaited.

Procedural risk factors for deep and organ/space surgical site infection post-coronary artery bypass graft surgery.

In this study, we examined the impact of the number and type of arterial grafts, and surgical dressing type, on deep and organ/space surgical site infection following coronary artery bypass graft procedures. Bilateral internal mammary artery grafts and negative pressure wound therapy were associated with higher odds of infection.

Prophylactic tranexamic acid for reducing blood loss in pregnant females undergoing cesarean section: A systematic review and meta-analysis.

OBJECTIVE: We aim to assess the efficacy of prophylactic tranexamic acid (TXA) in reducing blood loss after cesarean section (CS). METHODS: We systematically searched PubMed and Embase for randomized controlled trials published between 1990 and 2023 to conduct a meta-analysis on adult women undergoing CS and receiving prophylactic TXA. RESULTS: Twenty-four trials, comprising 19 584 participants, were included. Most studies included women with healthy, full-term, singleton pregnancies. The pooled estimate showed a reduction in mean blood loss in the TXA arm with a standardized mean difference (SMD) of -1.50 (-2.03, -0.98: p < 0.001). There was a high level of heterogeneity (I2 98.86%). A subgroup analysis demonstrated no statistical difference in the effect of TXA on blood loss at 2 h of follow-up with SMD of -2.24 (-3.23, -1.35) compared to -1.07 (-1.56, -0.58) and -1.10 (-2.62, -0.42) at 24 and 48 h, respectively (p = 0.11). The effect of TXA on blood loss was smaller in high-income countries with SMD -0.24 (-0.44, -0.04) (I2 63%) than in low-/middle-income countries -1.78 (-2.35, -1.21) with I2 98%. Only three studies had low risk of bias and the effect of TXA from two of them was SMD -0.31 (-0.54, -0.09) (I2 0%). CONCLUSIONS: Despite the apparent beneficial effect of TXA in reducing blood loss after CS for women with uncomplicated term pregnancies, heterogeneity remains a serious concern. The current body of knowledge consists predominantly of small, likely biased studies, and large unbiased studies show only limited effects of prophylactic TXA.