Can vancomycin lock therapy extend the retention time of infected long-term catheters?

Oral minocycline as systemic therapy for uncomplicated venous access device-related bloodstream infection with coagulase-negative staphylococci after allogeneic hematopoietic cell transplantation

BACKGROUND

Venous access device-related bloodstream infection (VAD-BSI) with coagulase-negative staphylococci (CoNS) is a common complication after allogeneic hematopoietic cell transplantation (alloHCT). Standard systemic antimicrobial therapy for uncomplicated VAD-BSI with methicillin-resistant CoNS consists of intravenous (IV) vancomycin (vanco). This requires hospitalization, needs new competent venous access, exposes patients to potential toxicity (mainly renal) and increases the risk of commensal flora dysbiosis with selection of vanco-resistant enterococci. Combined with VAD management (removal or antibiotic locks), oral minocycline (mino) has been evaluated as an alternative systemic therapy for the treatment of uncomplicated VAD-BSIs with CoNS at our center, primarily when the reference treatment with IV vanco was not possible (renal failure or allergy) or when hospitalization was refused by patients. Here, we retrospectively report our single center experience with this mino-based approach.

PATIENTS AND METHODS

From January 2012 to December 2020, 24 uncomplicated VAD-BSIs with CoNS in 23 alloHCT patients were treated with oral mino as systemic antibiotic therapy in combination with VAD management. VAD were implantable ports (n = 17), tunneled catheter (n = 1) or PIC-lines (n = 6). Staphylococci were S. epidermidis (n = 21) or S. haemolyticus (n = 3). Mino was administered with a loading dose of 200 mg followed by 100 mg BID for 7-14 days. For 8 VAD-BSIs, patients were initially treated with IV vanco for the first 1-3 days followed by oral mino, while 16 VAD-BSIs were treated with oral mino as the sole antimicrobial agent for systemic therapy. VAD management consisted of catheter removal (for tunneled catheters and PIC-lines, n = 7) or antibiotic locks with vanco (n = 15) or gentamicin (n = 2) administered at least 3 times a week for 14 days (for ports).

RESULTS

Overall, clearance of bacteremia (as assessed by negativity for the same CoNS of surveillance peripheral blood cultures drawn between day+ 3 and +30 after initiation of systemic therapy) was achieved in all but 1 patient (with port) who had persistent bacteremia at day +9. No complication such as suppurative thrombophlebitis, endocarditis, distant foci of infection or BSI-related death was observed in any patient during the 3-month period after initiation of treatment. Regarding the 17 port-BSI cases for which VAD conservative strategy was attempted, failure of 3-month VAD preservation was documented in 7/17 cases and 3-month recurrence of VAD-BSI was observed in 3/17 cases (with 1 patient with cellulitis). Treatment with mino was well tolerated except for a mild skin rash in one patient.

CONCLUSION

Further prospective studies are needed to evaluate efficacy and safety of this approach.

Usefulness of daptomycin lock therapy in children with catheter-related bacteremia after failed vancomycin lock therapy

PURPOSE

Catheter-related bacteremia (CRB) is a significant cause of morbidity, resource expenditure and prolonged hospital stays in patients with long-term catheters, whose numbers have increased considerably in recent years. Antibiotic lock therapy reaches high concentrations in the catheter, allowing good penetration into the biofilm, being vancomycin the most commonly used one in gram-positive infections. Several authors have recently reported the superior in vitro efficacy of daptomycin compared with vancomycin, especially for eradicating biofilms. Although there is some data on the use of daptomycin for antibiotic lock in animal models and adults, there are no data on its use in children.

METHODS

A descriptive study was conducted in a tertiary hospital, including patients younger than 16 years in whom daptomycin lock therapy was employed between 2018 and 2022.

RESULTS

We report three pediatric patients in whom CRB was confirmed on admission by paired blood cultures positive for CoNS sensitive to vancomycin, daptomycin and linezolid. All patients started vancomycin lock therapy and systemic antibiotic therapy with proven sensitivity for the isolated bacteria, without achieving negative blood cultures. Due to the persistence of positive cultures, vancomycin lock therapy was replaced by daptomycin, and blood cultures turned negative, with no relapses or need for catheter removal.

CONCLUSION

The use of daptomycin lock therapy could be considered in children with CoNS catheter infection, especially when other antibiotic lock therapy had failed.

TIVAP-related infection due to Gram-negative aerobic bacilli: should TIVAP stay or should it go?

We aimed to describe the outcome of totally implantable venous-access port (TIVAP)-related infections due to Gram-negative aerobic bacilli (Pseudomonas aeruginosa and other Pseudomonas spp., Acinetobacter spp., and Stenotrophomonas maltophilia), or GNAB, and assess the safety of conservative treatment. We conducted a retrospective study in a French teaching hospital, from January 2016 to December 2020, including adult patients treated for TIVAP-related infection due to GNAB. Success of conservative treatment was defined as a functional TIVAP 3 months after infection with no recurrence. We performed a bivariate analysis and analyzed causes for treatment failure. We included 68 patients (53 TIVAP-related bloodstream infections, 11 TIVAP-related infections, and 4 probable TIVAP-related infections) due to GNAB, mostly P. aeruginosa (50/68, 74%). TIVAP removal was initially decided for 49/68 patients (72%). Among the 19/68 (28%) patients with conservative treatment (all for infections caused by P. aeruginosa), 5/19 (26%) had successful treatment, 7/19 (37%) experienced failure (without sepsis or septic shock), 6/19 (32%) died within 3 months without TIVAP removal and no signs of infection recurrence, and 1 patient had TIVAP removal as it was no longer required. TIVAP-related infections caused by GNAB frequently require TIVAP removal. Conservative treatment can be performed in selected patients with a non-complicated infection caused by P. aeruginosa, who can benefit from the continuation of antineoplastic chemotherapy or palliative care. Treatment failures were not associated with sepsis or septic shock.

In Vivo Effectiveness of Several Antimicrobial Locks To Eradicate Intravascular Catheter Coagulase-Negative Staphylococci Biofilms

Tunneled central venous catheter (TCVC) related infection remains a challenge in the care of hemodialysis patients. We aimed to determine the best antimicrobial lock therapy (ALT) to eradicate coagulase-negative staphylococci (CoNS) biofilms. We studied the colonization status of the catheter every 30 days by quantitative blood cultures (QBC) drawn through all catheter lumens. Those patients with a significant culture (i.e.,100 to 1,000 CFU/mL) of a CoNS were classified as patients with a high risk of developing catheter-related bloodstream infections (CRBSI). They were assigned to receive daptomycin, vancomycin, teicoplanin lock solution, or the standard of care (SoC) (i.e., heparin lock). The primary endpoint was to compare eradication ability (i.e., negative QBC for 30 days after ending ALT) rates between different locks and the SoC. A second objective was to analyze the correlation between ALT exposure and isolation of CoNS with antimicrobial resistance. Daptomycin lock was associated with a significant higher eradication success than with the SoC: 85% versus 30% (relative risk [RR] = 14, 95% confidence interval [CI] = 2.4 - 82.7); followed by teicoplanin locks with a 83.3% success (RR = 11.7; 95% CI = 2 - 70.2). We observed CoNs isolates with a higher teicoplanin MIC in patients with repeated teicoplanin locks exposure (coefficient = 0.3; 95% CI = 0.11 - 0.47). However, teicoplanin MICs decreased in patients treated with vancomycin locks (coefficient = -0.56; 95% CI = -0.85 - -0.02). Methicillin-resistance decreased with accumulative ALT (RR = 0.82; 95% CI = 0.69 - 0.98). In this study, daptomycin locks achieve the highest eradication rate of CoNS from hemodialysis catheters in vivo.

Stability of vancomycin hydrochloride employed in antimicrobial seal solutions of central intravenous catheters

OBJECTIVE

to verify the stability of vancomycin hydrochloride in antimicrobial seal solutions with and without association of heparin sodium according to temperature and association time.

METHOD

an experimental study designed for the analysis of hydrogenionic potential and concentration by means of high-efficiency liquid chromatography of vancomycin hydrochloride (n=06) and vancomycin hydrochloride and heparin sodium (n=06). The solutions studied were submitted to absence of light, as well as to 22°C and 37°C. Analyses in triplicate (n=192) were performed at the initial moment (T0) and three (T3), eight (T8) and 24 hours (T24) after preparation. The data were submitted to analysis of variance (p≤0.05).

RESULTS

concentration of the antimicrobial at 22°C presented a reduction (T0-T8) and a subsequent increase (T24); hydrogenionic potential decreased significantly over time. At 37°C, the concentration increased up to T3 and decreased at T24, with a reduction of hydrogenionic potential up to 24 hours. Concentration of the vancomycin hydrochloride and heparin sodium solutions varied with a reduction at 22°C, accompanied by increased hydrogenionic potential. Precipitate formation was observed by visual inspection of the vancomycin hydrochloride-heparin sodium association (T3).

CONCLUSION

pharmacological stability of vancomycin hydrochloride (5 mg/mL) and physical incompatibility with heparin sodium (100 IU/mL) were evidenced after three hours of association in the antimicrobial seal solutions studied.

Estabilidad del clorhidrato de vancomicina utilizado en soluciones de sellado antimicrobiano para catéteres intravenosos centrales

Resumen Objetivo: verificar la estabilidad del clorhidrato de vancomicina en soluciones de sellado antimicrobiano solo y combinado con heparina sódica según la temperatura y el tiempo de combinación. Método: estudio experimental diseñado para analizar el potencial de hidrógeno y la concentración por cromatografía líquida de alta resolución de soluciones de clorhidrato de vancomicina (n=06) y de clorhidrato de vancomicina y heparina sódica (n=06). Las soluciones estudiadas fueron sometidas a ausencia de luz, 22°C y 37°C. Se realizaron análisis por triplicado (n=192) en el momento inicial (T0), a las tres (T3), ocho (T8) y 24 horas (T24) después de la preparación. Los datos fueron sometidos a análisis de varianza (p≤0,05). Resultados: la concentración de antimicrobiano a 22°C mostró una reducción (T0-T8) y un posterior aumento (T24); el potencial de hidrógeno disminuyó significativamente con el tiempo. A 37°C, la concentración aumentó hasta T3 y disminuyó en T24, el potencial de hidrógeno disminuyó hasta las 24 horas. La concentración de las soluciones de clorhidrato de vancomicina y heparina sódica mostró variación con la reducción a 22°C acompañada de un aumento del potencial de hidrógeno. Mediante inspección visual se observó la formación de un precipitado al combinar clorhidrato de vancomicina y heparina sódica (T3). Conclusión: el clorhidrato de vancomicina (5 mg/ml) presentó evidencia de estabilidad farmacológica e incompatibilidad física con la heparina sódica (100 UI/ml) después de las tres horas de haberse realizado la combinación en las soluciones de sellado antimicrobiano estudiadas.

Stability of vancomycin hydrochloride employed in antimicrobial seal solutions of central intravenous catheters

Abstract Objective: to verify the stability of vancomycin hydrochloride in antimicrobial seal solutions with and without association of heparin sodium according to temperature and association time. Method: an experimental study designed for the analysis of hydrogenionic potential and concentration by means of high-efficiency liquid chromatography of vancomycin hydrochloride (n=06) and vancomycin hydrochloride and heparin sodium (n=06). The solutions studied were submitted to absence of light, as well as to 22°C and 37°C. Analyses in triplicate (n=192) were performed at the initial moment (T0) and three (T3), eight (T8) and 24 hours (T24) after preparation. The data were submitted to analysis of variance (p≤0.05). Results: concentration of the antimicrobial at 22°C presented a reduction (T0-T8) and a subsequent increase (T24); hydrogenionic potential decreased significantly over time. At 37°C, the concentration increased up to T3 and decreased at T24, with a reduction of hydrogenionic potential up to 24 hours. Concentration of the vancomycin hydrochloride and heparin sodium solutions varied with a reduction at 22°C, accompanied by increased hydrogenionic potential. Precipitate formation was observed by visual inspection of the vancomycin hydrochloride-heparin sodium association (T3). Conclusion: pharmacological stability of vancomycin hydrochloride (5 mg/mL) and physical incompatibility with heparin sodium (100 IU/mL) were evidenced after three hours of association in the antimicrobial seal solutions studied.

Comparing success rates in central venous catheter salvage for catheter-related bloodstream infections in adult patients on home parenteral nutrition: a systematic review and meta-analysis

BACKGROUND

Catheter-related bloodstream infection (CRBSI) is a life-threatening complication of parenteral nutrition. Therefore, optimal management, ideally with catheter salvage, is required to maintain long-term venous access.

OBJECTIVES

We aimed to evaluate successful catheter salvage rates in patients on home parenteral nutrition (HPN).

METHODS

Studies were retrieved from medical databases, conference proceedings, and article reference lists. Data were collected relating to clinical outcomes of 3 treatments: systemic antibiotics, antimicrobial lock therapy (ALT), and catheter exchange. ORs and 95% CIs were calculated from a mixed logistic effects model.

RESULTS

From 10,036 identified publications, 28 met the inclusion criteria (22 cohort studies, 5 case-control studies, and 1 randomized clinical trial), resulting in a total of 4911 CRBSIs. To achieve successful catheter salvage, the addition of an antimicrobial lock solution was superior to systemic antibiotics alone (OR: 1.75; 95% CI: 1.21, 2.53; P = 0.003). Recurrence of infection was less common in studies that used ALT than in those that used systemic antibiotics alone (OR: 0.26; 95% CI: 0.11, 0.61; P = 0.002). The catheter exchange group was excluded from multilevel regression analysis because only 1 included study applied this treatment. Successful salvage rates were highest for coagulase-negative staphylococci, followed by Gram-negative rods and Staphylococcus aureus .

CONCLUSIONS

The addition of an antimicrobial lock solution seems beneficial for successful catheter salvage in HPN-dependent patients with a CRBSI. Future prospective randomized studies should identify the most effective and pathogen-specific strategy.This review was registered at www.crd.york.ac.uk/PROSPERO as CRD42018102959.

Equal effect of vancomycin lock with or without heparin in treatment of central venous catheter related blood stream infections - an observational study in palliative home care

BACKGROUND

Catheter related blood stream infections is a complication in patients with central venous catheter. The aim of this study was to compare vancomycin-heparin-lock and non-heparin, high-dose vancomycin-lock as treatment in patients admitted to palliative home care. With non-heparin, high-dose vancomycin-lock a high concentration of 5 mg/mL vancomycin is attained instead of only 500 ug/mL when dissolved in heparin. The non-heparin method also has the advantage of being easier and cheaper but might entail an increased risk of clotting.

METHODS

Medical records from patients enrolled at a palliative home care unit in Stockholm between 2016 and 2018 were reviewed retrospectively. Three divisions used vancomycin-heparin-lock and the other 3 divisions used non-heparin, high-dose vancomycin-lock. Inclusion criteria were a central venous catheter related blood stream infection treated with one of the two methods for >7 days and a follow-up blood culture at the end of treatment.

RESULTS

Twenty-five patients fulfilled the inclusion criteria, 12 treated with vancomycin-heparin-lock and 13 with non-heparin, high-dose vancomycin-lock. There was no significant difference in resolved infections between the two treatments, 6 of 12 for vancomycin-heparin-lock and 10 of 13 for non-heparin, high-dose vancomycin-lock (p = .23). In the non-heparin group one central venous catheter was removed due to clotting although the infection had resolved. Overall, removal of central venous catheter was similar in the two groups (6 of 12 and 4 of 13, p = .43).

CONCLUSION

The current study does not support superiority of one treatment over the other. However, larger, randomized studies are needed, before firm conclusions can be drawn.