Algorithm Reduces Antibiotic Use in Lower Respiratory Tract Infection

Lung infection
Lung infection
The duration of antibiotic regimens to treat lower respiratory tract infection can be reduced through the use of a procalcitonin-guided algorithm.

The duration of antibiotic regimens to treat lower respiratory tract infection can be reduced through the use of a procalcitonin-guided algorithm, according to a study published in Open Forum Infectious Diseases. This cessation algorithm may be helpful in the ongoing effort to lower antibiotic use.

This study included 174 participants in the intervention group and 200 participants in the control group, all of whom had lower respiratory tract infection. Control participants were treated with usual care while participants in the intervention group were given a regimen of antibiotics guided by procalcitonin levels. Antibiotics were discontinued when procalcitonin levels reached ≥80% below the maximum value. Discontinuation of antibiotics within 2 days of crossing this threshold constituted adherence to the algorithm.

The primary end point of the study was median duration of antibiotic use within 1 month of discharge per lower respiratory tract infection episode. The primary safety end point —adverse outcomes at 30 days— included post-discharge prescription of antibiotics, Clostridium difficile infection, mortality, and intensive care unit transfer. The Wilcoxon rank-sum test and student t tests were used to compare continuous variables of data and outcomes between the groups, while categorical variables were compared using Fisher exact or χ2 tests.

At baseline, procalcitonin values were mostly (65%) below the antibiotic recommendation threshold of 0.25 µg/L. The procalcitonin algorithm was followed in 75% of cases. The intervention group had a median of 5 days of antibiotic duration compared with 6 days in controls (P =.052). However, the intervention group had a significantly lower percentage of patients discharged with antibiotics  (37.4% vs 55.5%; P <.001) and a significantly lower total number of days taking antibiotics (1883 vs 2039 days of therapy per 1000 days present; incidence rate ratio, 0.92; 95% CI, 0.86-0.99). There was also a reduction from 4 days to 3 in the intervention group in acute exacerbation of chronic obstructive pulmonary disease (P <.001). Adverse outcome rates did not differ between the groups.

Limitations to this study included having only internal medicine services, control periods during different times of year, a lack of randomization, and a 36-hour delay in results that could have limited the effect of the intervention.

The researchers concluded that “[procalcitonin]-guided cessation of antibiotic therapy, when undertaken as a stewardship intervention, is a safe and effective strategy to reduce antibiotic use in patients with [lower respiratory tract infection].”

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Disclosures: This study received funding from B·R·A·H·M·S GmbH. Author J Townsend reports financial associations with the same company. For other author disclosures, please visit the reference.


Townsend J, Adams V, Galiatsatos P, et al. Procalcitonin-guided antibiotic therapy reduces antibiotic use for lower respiratory tract infections in a United States medical center: results of a clinical trial. Open Forum Infect Disord. 2018;5(12):ofy327