Effect of Preoperative Antibiotic Therapy on Operative Culture Yield for Diagnosis of Native Joint Septic Arthritis

BACKGROUND

Native joint septic arthritis (NJSA) is definitively diagnosed by a positive Gram stain or culture, along with supportive clinical findings. Preoperative antibiotics are known to alter synovial fluid cell count, Gram stain and culture results and are typically postponed until after arthrocentesis to optimize diagnostic accuracy. However, data on the impact of preoperative antibiotics on operative culture yield for NJSA diagnosis are limited.

METHODS

We retrospectively reviewed adult cases of NJSA who underwent surgery at Mayo Clinic facilities from 2012-2021 to analyze the effect of preoperative antibiotics on operative culture yield through a paired analysis of preoperative culture (POC) and operative culture (OC) results using logistic regression and generalized estimating equations.

RESULTS

Two hundred ninety-nine patients with NJSA affecting 321 joints were included. Among those receiving preoperative antibiotics, yield significantly decreased from 68.0% at POC to 57.1% at OC (p < .001). In contrast, for patients without preoperative antibiotics there was a non-significant increase in yield from 60.9% at POC to 67.4% at OC (p = 0.244). In a logistic regression model for paired data, preoperative antibiotic exposure was more likely to decrease OC yield compared to non-exposure (OR = 2.12; 95% CI = 1.24-3.64; p = .006). Within the preoperative antibiotic group, additional antibiotic doses and earlier antibiotic initiation were associated with lower OC yield.

CONCLUSION

In patients with NJSA, preoperative antibiotic exposure resulted in a significant decrease in microbiologic yield of operative cultures as compared to patients in whom antibiotic therapy was held prior to obtaining operative cultures.

Characteristics and management of periprosthetic joint infections caused by rapidly growing mycobacteria: a retrospective study and a review of the literature

Background: Periprosthetic joint infection (PJI) following total joint arthroplasty is a serious complication associated with significant morbidity. While Gram-positive cocci are the predominant causative organisms, PJIs caused by rapidly growing mycobacteria (RGM) have been reported, albeit at a lower frequency. This study aimed to investigate the characteristics and management of PJI caused by RGM. Methods: A retrospective review was conducted using an institutional PJI database to identify patients diagnosed with PJI due to RGM from January 2010 to December 2021. Clinical data, including demographics, symptoms, comorbidity information, laboratory parameters, surgical procedures, medical treatment and outcomes, were collected and analyzed. Results: A total of eight patients were identified with PJI caused by RGM during the study period. The median age was 66 years old, and most cases occurred in patients with total knee arthroplasty (n = 6 ). The isolated RGM species included Mycobacterium abscessus (three cases), M. fortuitum (three cases), and one case each of M. immunogenum and M. mageritense. Surgical debridement was performed in all cases, with six patients undergoing two-stage revision and two patients requiring amputation. Combination antimicrobial therapy was administered based on antimicrobial susceptibility testing, and the median duration of treatment was 7.5 months. Adverse events related to therapy occurred in 75 % of cases. No relapses were observed during the median follow-up period of 39.6 months. Conclusions: PJI caused by RGM is a rare complication of total joint arthroplasty. Surgical debridement and combination antimicrobial therapy are the mainstays of treatment. Although clinical cure rates are high, amputation may be required in severe cases.

Real-life effectiveness of COVID-19 vaccine during the Omicron variant-dominant pandemic: how many booster doses do we need?

The surge in coronavirus disease 2019 (COVID-19) caused by the Omicron variants of the severe acute respiratory syndrome coronavirus 2 necessitates researches to inform vaccine effectiveness (VE) and other preventive measures to halt the pandemic. A test-negative case-control study was conducted among adults (age ≥18 years) who were at-risk for COVID-19 and presented for nasopharyngeal real-time polymerase chain reaction testing during the Omicron variant-dominant period in Thailand (1 January 2022-15 June 2022). All participants were prospectively followed up for COVID-19 development for 14 days after the enrolment. Vaccine effectiveness was estimated and adjusted for characteristics associated with COVID-19. Of the 7971 included individuals, there were 3104 cases and 4867 controls. The adjusted VE among persons receiving 2-dose, 3-dose, and 4-dose vaccine regimens for preventing infection and preventing moderate-to-critical diseases were 33%, 48%, 62% and 60%, 74%, 76%, respectively. The VE were generally higher among those receiving the last dose of vaccine within 90 days compared to those receiving the last dose more than 90 days prior to the enrolment. The highest VE were observed in individuals receiving the 4-dose regimen, CoronaVac-CoronaVac-ChAdOx1 nCoV-19-BNT162b2 for both preventing infection (65%) and preventing moderate-to-critical diseases (82%). Our study demonstrated increased VE along with an increase in number of vaccine doses received. Current vaccination programmes should focus on reducing COVID-19 severity and mandate at least one booster dose. The heterologous boosters with viral vector and mRNA vaccines were highly effective and can be used in individuals who previously received the primary series of inactivated vaccine.

Comparing real-life effectiveness of various COVID-19 vaccine regimens during the delta variant-dominant pandemic: A test-negative case-control study

Data on real-life vaccine effectiveness (VE), against the delta variant (B.1.617.2) of the severe acute respiratory syndrome coronavirus 2 among various coronavirus disease 2019 (COVID-19) vaccine regimens are urgently needed to impede the COVID-19 pandemic. We conducted a test-negative case-control study to assess the VE of various vaccine regimens for preventing COVID-19 during the period when the delta variant was the dominant causative virus (≥ 95%) in Thailand (25 July 2021–23 Oct 2021). All individuals (age ≥18 years) at-risk for COVID-19, presented for nasopharyngeal real-time polymerase chain reaction (RT-PCR) testing, were prospectively enrolled and followed up for disease development. Vaccine effectiveness was estimated with adjustment for individual demographic and clinical characteristics. Of 3353 included individuals, there were 1118 cases and 2235 controls. The adjusted VE among persons receiving two-dose CoronaVac plus one BNT162b2 booster was highest (98%; 95% confidence interval [CI] 87–100), followed by those receiving two-dose CoronaVac plus one ChAdOx1 nCoV-19 booster (86%; 95% CI 74–93), two-dose ChAdOx1 nCoV-19 (83%; 95% CI 70–90), one CoronaVac dose and one ChAdOx1 nCoV-19 dose (74%; 95% CI 43–88) and two-dose CoronaVac (60%; 95% CI 49–69). One dose of CoronaVac or ChAdOx1 nCoV-19 had a VE of less than 50%. Our study demonstrated the incremental VE with the increase in the number of vaccine doses received. The two-dose CoronaVac plus one BNT162b2 or ChAdOx1 nCoV-19 booster regimens was highly effective in preventing COVID-19 during the rise of delta variant.

Nocardia intracranial mycotic aneurysm associated with proteasome inhibitor

We report a case of Nocardia farcinica ruptured intracranial mycotic aneurysm associated with bortezomib and corticosteroid treatment in a multiple myeloma patient. The patient was treated with trimethoprim-sulfamethoxazole and moxifloxacin together with surgical repairment of intracranial mycotic aneurysm.

A case of secondary syphilis with pulmonary involvement and review of the literature

Syphilis is a sexually transmitted systemic infection caused by Treponema pallidum. We report a case of a heterosexual, HIV-positive man who presented with secondary syphilis and a lung abscess. A bacterial lung abscess was suspected and a computed tomography-guided percutaneous needle aspiration of the lung abscess was performed. Direct pulmonary involvement by T. pallidum was suggested by a positive PCR result on the aspirated fluid specimen. The clinical signs of secondary syphilis improved, and the lung abscess was resolved after treatment with benzathine penicillin G and amoxicillin-clavulanate. The final diagnosis was secondary pulmonary syphilis. Few reports of secondary syphilis with pulmonary involvement have been reported to date.

Enhanced inpatient rounds, appointment reminders, and patient education improved HIV care engagement following hospital discharge

Human immunodeficiency virus (HIV) care engagement post hospital discharge is often suboptimal. Strategies to improve follow-up are needed. A quasi-experimental study was conducted among hospitalized HIV-infected patients between the period from 1 January 2013 to 30 June 2014 (preintervention period) and 1 July 2014 to 31 December 2015 (intervention period). During the intervention period, an HIV care team consisting of an Infectious Diseases physician, a nurse, a pharmacist, a social worker, and an HIV-infected volunteer made daily inpatient rounds. Prior to discharge, patients received a structured HIV education session and an outpatient appointment was scheduled for them with two telephone reminder calls following discharge. There were 240 HIV-infected patients enrolled (120 in each study period), of which the median age was 37 years (interquartile range [IQR] 28-44 years), 58% were male, 39% were newly diagnosed with HIV infection, 46% were hospitalized because of AIDS-related conditions, and the median CD4 cell count on admission was 158 cells/µl (IQR 72-382 cells/µl). The rate of HIV care engagement within 30 days after discharge was significantly higher in the intervention period compared to the preintervention period (95% versus 69%; P < 0.001). Independent factors associated with no care engagement within 30 days were patients in the preintervention period (adjusted odds ratio [aOR] 6.36; P < 0.001) and new diagnosis of HIV infection (aOR 2.77; P = 0.009). The study findings suggest that enhanced inpatient rounds, appointment reminders, and patient education were shown to be associated with improved HIV care engagement after hospital discharge. Patients with a new diagnosis of HIV infection benefit from more intense outreach. ClinicalTrials.gov Identifier: NCT02578654.

Inappropriate Empirical Treatment of Uncomplicated Cystitis in Thai Women: Lessons Learned

A prospective study conducted in a Thai general practice clinic demonstrated a high prevalence (91.3%) of inappropriate empirical antibiotic use in women with uncomplicated cystitis and 42.6% Escherichia coli fluoroquinolone resistance. An annual update of antimicrobial resistance surveillance data of uropathogens may permit targeted treatment of patients in hospital care.

Disseminated Talaromyces marneffei and Mycobacterium abscessus in a Patient With Anti-Interferon-γ Autoantibodies

Anti-interferon (IFN)-γ autoantibodies are increasingly recognized as a cause of adult-onset immunodeficiency and increased risk for infections with intracellular pathogens. We report on disseminated Talaromyces (Penicillium) marneffei and Mycobacterium abscessus infection in a 72-year-old, human immunodeficiency virus noninfected, Thai man with anti-IFN-γ autoantibody. The patient was successfully treated with antimicrobial therapy and rituximab to control B cell-derived autoantibodies.

A pharmacogenomic prospective randomized controlled trial of CYP2B6 polymorphisms and efavirenz dose adjustment among HIV-infected Thai patients: a pilot study

OBJECTIVE

We aimed at comparing clinical/immunological outcomes in human immunodeficiency virus (HIV)-infected patients who were treated with CYP2B6-guided and conventional efavirenz (EFV) therapy.

METHODS

This study was a 24-week prospective randomized controlled trial. Eligible patients were HIV-infected adults yet to start antiretroviral therapy. Twenty-four HIV-infected patients were recruited and randomly assigned to genotype CYP2B6 polymorphism before ART initial dose. Patients with CYP2B6 *6/*6 received 400 mg EFV-based regimen and those with other genotypes received 600 mg EFV-based therapy.

RESULTS

For CYP2B6 polymorphism, 12 patients were extensive metabolizers, ten patients were intermediate metabolizers, and only two patients were poor metabolizers (*6/*6). The overall mean EFV plasma concentrations were similar in both groups. The mean drug concentrations (standard deviation) were 1.675 (0.963), 1.445 (0.778), and 1.899 (0.808) µg/mL at week 4, 12, and 24, respectively. The CYP2B6 *6/*6 patient who received low dose of EFV had lower mean EFV level than those who received a normal dose, 1.916 versus 3.915 µg/mL (P<0.001), respectively. Seventy percent of the patients had neuropsychiatric adverse events, especially dizziness.

DISCUSSION

There was a trend toward association of the CYP2B6 polymorphism and plasma EFV concentrations in this study. Reduced EFV dose should be considered in CYPB6 *6/*6 carrier to keep the drug concentration in therapeutic range.