SURVEILLANCE CULTURES IN BONE-MARROW TRANSPLANT RECIPIENTS - WORTHWHILE OR WASTEFUL

A prospective study of the value of surveillance cultures was performe d in a bone marrow transplant (BMT) unit among 48 consecutive patients . All patients were admitted to laminar airflow or high-efficiency par ticulate air (HEPA) filtered rooms, maintained on reduced microbial di ets and received oral non-absorbable antibiotics. With the onset of ne utropenia, all patients received imipenem/cilastatin and 17 patients r eceived low-dose amphotericin B 0.1 mg/kg/day. Pre-transplant and week ly post-transplant cultures of the stool, throat and urine were obtain ed on all patients. Nasal and vaginal cultures were performed on 26 pa tients. Sixteen patients developed 23 documented infections. The sensi tivity of surveillance cultures for all infections was 38%, specificit y 25%, positive predictive value 20% and negative predictive value 44% . When stratified by organisms, the sensitivity, specificity, positive predictive value and negative predictive value were: Gram positive in fections, 33%, 36%, 11%, 70%; Gram negative infections, 17%, 88%, 17%, 88%; fungal infections 37%, 50%, 11%, 75%; and Candida albicans, 100% , 57%, 14%, 100%. These data suggest that surveillance cultures may be useful to exclude C. albicans infections but are of limited value in predicting other types of infections in recipients of BMT.