We sought to determine the rate of incident neutropenia and identify potential clinical factors associated with incident neutropenia among patients treated with long courses of ceftaroline.Methods
We retrospectively identified adult patients who received ceftaroline for ≥7 days consecutively at two large academic medical centres in Boston, USA between November 2010 and March 2015. Clinical characteristics (age, gender, medication allergies, baseline renal function, duration of ceftaroline exposure, total daily ceftaroline dose, body mass-adjusted ceftaroline dose and development of rash and neutropenia) were recorded and the rate of incident neutropenia was calculated. The Naranjo probability scale was used to assess whether ceftaroline exposure was associated with neutropenia. We assessed whether clinical factors were associated with neutropenia.Results
The overall rate of incident neutropenia was 10%–14% with ≥2 weeks and 21% with ≥3 weeks of ceftaroline exposure. The median duration of ceftaroline exposure [26 days (IQR 22–44; range 13–68) in patients who developed neutropenia and 15 days (IQR 9–29; range 7–64) in patients without neutropenia] was associated with incident neutropenia (P = 0.048). The median total number of ceftaroline doses received [63 (IQR 44–126; range 36–198) by neutropenic patients and 32 (IQR 22–63; range 14–180) by non-neutropenic patients] was also associated with incident neutropenia (P = 0.023).Conclusions
The overall rate of neutropenia was high and associated with duration of ceftaroline exposure and total number of doses received. Close laboratory monitoring is warranted with long-term ceftaroline use.