Outbreak of Burkholderia cepacia complex bacteremia in a chemotherapy day care unit due to intrinsic contamination of an antiemetic drug

Background: In the end of 2009, a large number of patients with cancer undergoing chemotherapy at the day care unit of a private hospital in Mumbai, India developed Burkholderia cepacia complex (BCC) blood stream infection (BSI). Objective: The objectives were to identify the source of the outbreak and terminate the outbreak as rapidly as possible. Materials and Methods: All infection control protocols and processes were reviewed. Intensive training was started for all nursing staff involved in patient care. Cultures were sent from the environment (surfaces, water, air), intravenous fluids, disinfectants and antiseptics and opened/unopened medication. Results: A total of 13 patients with cancer with tunneled catheters were affected with BCC BSI. The isolates were of similar antimicrobial sensitivity. No significant breach of infection control protocols could be identified. Cultures from the prepared intravenous medication bags grew BCC. Subsequently, culture from unused vials of the antiemetic granisetron grew BCC, whereas those from the unopened IV fluid bag and chemotherapy medication were negative. On review, it was discovered that the outbreak started when a new brand of granisetron was introduced. The result was communicated to the manufacturer and the brand was withdrawn. There were no further cases. Conclusions: This outbreak was thus linked to intrinsic contamination of medication vials. We acknowledge a delay in identifying the source as we were concentrating more on human errors in medication preparation and less on intrinsic contamination. We recommend that in an event of an outbreak, unopened vials be cultured at the outset.     

Staphylococcus aureus Bacteremia in Patients with Hematological Malignancies and/or Agranulocytosis

ABSTRACT. A total of 6 253 cases of Staphylococcus aureus bacteremia, including 274 (4.4%) endocarditis cases, were registered in Denmark in the period 1975–1984. Patients with hematological malignancies and/or agranulocytosis accounted for 479 of the bacteremia cases. The incidence of endocarditis in this group of patients was only 0.4% as compared to 4.7% in other patients with staphylococcal bacteremia (p<0.01). The lower incidence of endocarditis complicating bacteremia in these patients may justify a shorter course of therapy than usually recommended for suspected endocarditis. Patients with hematological malignancies and other patients with agranulocytosis had a higher mortality (49 and 46%, respectively) than other patients with S. aureus bacteremia (33%). The highest mortality was found in patients with multiple myeloma (71%, p<0.01), the lowest in patients with acute lymphocytic leukemia (28%, p<0.01). The higher mortality in these patients may indicate that empiric antibiotic regimens in granulocytopenic patients should include a specific anti-staphylococcal agent.     

Early and late onset bacteremia have different risk factors in trauma patients

Objective The aim of this study was to identify risk factors and to describe epidemiological patterns for early—(EOB) and late—onset bacteremias (LOB) after trauma.Design A prospective study conducted on 141 consecutive trauma patients.Setting A general intensive care unit (ICU) of a university hospital.Patients All multiple trauma patients admitted to our general intensive care unit (ICU) from December 1990 to May 1992 were prospectively enrolled in the study. The following information was collected for each patient and recorded in a computer database: demography, severity of trauma according to the Abbreviated Injury Scale (AIS), severtity of trauma according to the Glasgow Coma Scale (GCS), presence of pneumothorax, pulmonary contusion, rib fractures, hemothorax, and abdominal trauma, use of mechanical ventilation, and placement of central venous catheters. Bacteremias were defined as EOB when onset occurred within 96 h after trauma, and as LOB when appearing after 96 h from trauma.Results Thirty-seven patients developed bacteremia during their ICU stay (26%): 11 (29.7%) EOB and 26 (70.3%) LOB. Gram-positive cocci were isolated more frequently in EOB than in LOB (x ²=4.1,P=0.04). The risk of EOB was significantly increased by the presence of pulmonary contusion [relative risk (RR) 15.0; confidence interval (CI) 1.99-113.25], pneumonia before the onset of bacteremia (RR 3.56; CI 1.17-10.69), AIS score greater than 32 and an abdominal injury score greater than 9 (RR 3.11; CI 1.02-9.49), while intravascular catheters and mechanical ventilation did not represent risk factors for EOB. LOB had a very different pattern and their risk was significantly increased by exposure to intravascular catheters (RR 4.96; CI 1.23-19.94) and to mechanical ventilation lasting more than 7 days (RR 3.6; CI 1.6-8.1).Conclusions Scoring with the AIS of the abdominal and thoracic trauma at admission to the ICU appears a useful tool for identifying trauma patients at increased risk of EOB. A rigorous policy of catheter placement and maintenance as a means of reducing late bacteremias in trauma patients is essential.     

Human cytomegalovirus, human herpesvirus-6 and human herpesvirus-7 in neutropenic patients with fever of unknown origin

Objective  To investigate the appearance of cytomegalovirus (CMV) DNA, human herpesvirus-6 (HHV-6) DNA and human herpesvirus-7 (HHV-7) DNA in plasma as a sign of reactivation and possible causes of fever of unknown origin (FUO) during neutropenia.
Methods  From 134 patients with febrile neutropenia following cytotoxic chemotherapy during the years 1996–2000, 20 severely neutropenic patients (granulocyte count < 0.1 × 10⁹/L) were selected. Ten were patients with bacteremia and ten were patients with FUO. Five samples from each patient were selected at the start of chemotherapy, at the time of blood culture and fever, after 24 and 48 hours of fever, and, finally, after two to three days without fever. Virus DNA was detected by real-time quantitative and nested polymerase chain reaction (PCR).
Results  CMV-DNA was detected in two out of ten FUO-patients in all samples drawn during fever. From another FUO and during two bacteremia episodes, CMV-DNA was detected after 48 hours of fever. DNA from HHV-6 and HHV-7 was not detected in any of the 20 febrile episodes.
Conclusions  HHV-6 and HHV-7 as a possible explanation for FUO in severely neutropenic patients treated with cytotoxic chemotherapy seems not be very likely. However, CMV was identified in 5/20 patients and the febrile episodes in the two FUO-patients with constant DNA-emia may have been caused by a reactivation of CMV. This implies that CMV infection can be expected not only in transplant patients but also in chemotherapy-treated neutropenic patients.     

白念珠菌菌血症诱导小鼠皮质胸腺细胞凋亡

采用白念珠菌诱导小鼠胸腺内细胞凋亡 ,对其发生部位和累及的胸腺内细胞表型进行了研究。结果发现 :静脉注射白念珠菌入小鼠体内 6h后 ,开始出现胸腺细胞凋亡 ;1 2h ,1 8h和 2 4h胸腺凋亡细胞百分率不断增加 ;CD3+和CD8+细胞百分率均较对照组有明显的下降 ;胸腺内细胞凋亡主要发生在皮质区 ,而髓质区则少。表明白念珠菌能诱导小鼠胸腺细胞凋亡 (主要是未成熟CD3+CD4+CD8+细胞及少量成熟的CD3+CD4- CD8+细胞 )     

Outbreak of nosocomialAcinetobacter baumannii bacteremia in a high risk ward

Acinetobacter baumannii is emerging as a major cause of nosocomial infections particularly in high risk patients. Being resistant to adverse environmental conditions, it can stay for prolonged periods in the hospital environment. We report an outbreak in the medical oncology ward where nine patients suspected of bacteraemia were blood culture positive forA. baumannii from the two samples each, one collected through the i.v. cannula and another through the peripheral venous puncture. The bacteria was also isolated from the environmental sources from the various samples collected. The biotype, antibiogram, cellular protein profiles on SDS-PAGE and the restriction enzyme analysis patterns of the patient isolates and the environmental isolates were similar. This points to the environment as a source of infection. With reinforcement of proper barrier nursing and use of disposable heparine ampoules it was possible to control the outbreak.