IDSA 2011: Antimicrobial Agent Shortages

BOSTON, MA—Almost four out of five infectious disease specialists have had to prescribe an alternative antimicrobial agent due to drug shortages, and half of these report that the resulting change adversely affected patient care or outcomes, a survey finds. The results of the survey were reported by Susan E. Beekmann, RN, MPH, program coordinator of the Infectious Diseases Society of America Emerging Infections Network (IDSA EIN) during an oral abstract session at the IDSA annual meeting titled “Infectious Disease Practice Challenges.”

The nine-question survey was sent to all 1,350 members of the IDSA EIN this May, and 634 (47%) responded. Of these, 78% reported having had to modify their antimicrobial agent of choice to treat infectious disease over the preceding two years, though the results varied by region and type of practice or hospital. Using US Census Bureau regions, the East North Central region (including Illinois, Indiana, Michigan, Ohio, and Wisconsin) had the highest shortage rate (83%), while New England had the lowest shortage rate (62%). Those in private or group practices had the highest shortage rate (85%), while those in the military had the lowest shortage rate (50%). Those in non-university teaching hospitals had the highest shortage rate (over 80%), while those in VA or military hospitals had the lowest shortage rate.

The top five drugs with reported shortages were all injectable: trimethoprim-sulfamethoxazole (TMP/SMX) (64%), amikacin (57%), aztreonam (32%), foscarnet (22%), and penicillin G (17%). Oral agents with shortages included oseltamivir oral suspension and acyclovir tablets, while other injectables with shortages included intravenous immune globulin, live zoster vaccine, yellow fever vaccine, and inactivated influenza vaccine.

Of the physicians who reported experiencing a shortage, 52% said the resulting medication change adversely affected patient care or outcomes. Of those reporting adverse effects, the most commonly named was replacement of the desired antimicrobial with a more toxic alternative (63%), followed by replacement with a more expensive alternative (41%), replacement with broader-spectrum antimicrobials (39%), long-term morbidity from inadequate treatment (28%), and longer hospitalizations (26%). In addition, five respondents indicated that a patient died at least in part due to the shortage of a specific antimicrobial agent.

Beekmann noted that she and her fellow researchers were disturbed to find that 70% of physicians surveyed learned of a shortage from a pharmacy after prescribing a drug, while just 24% learned of it from official sources, such as the FDA drug shortages website.

Among the limitations of the survey results, Beekmann noted that they were self-reported with no verification, that those who had experienced shortages may have been more eager to share their experiences, and that there had been no effort to determine why shortages occur.

Beekmann finished by suggesting that the results indicate a need for an improved strategy for alerting physicians of impending or current shortages as well as for better information on alternative agents that can be substituted when the preferred ones are unavailable.