Controlled comparison of BacT/ALERT FAN aerobic medium and BATEC fungal blood culture medium for detection of fungemia

Yeasts are an increasingly common cause of nosocomial bloodstream infections. Methods for their detection are many; controlled comparisons are few. The vented FAN aerobic blood culture medium has been shown to be superior to the standard BacT/ALERT aerobic medium for the detection of fungemia as well as bacteremia. The BACTEC selective fungal medium (FM) (BD Biosciences, Sparks, Md.) allowed detection of more episodes of fungemia than did a resin-containing medium with equal volumes of blood cultured. Therefore, we compared vented FAN to FM for the ability to recover fungi from the blood of patients who were at increased risk of having fungemia. From 5,109 cultures processed for which both FAN and FM bottles were adequately filled, fungi were recovered from 87 cultures. Of these, 47 were detected with both bottles, 12 were detected with FAN only, and 28 were detected with FM only (P < 0.05). FAN was the first bottle positive for 36 of the 47 cultures for which both bottles yielded the same fungus, whereas the FM bottle was the first bottle positive for 11 cultures (P < 0.001). A total of 54 episodes of fungemia were identified, with 40 detected by both media, 4 detected only by FAN, and 10 detected only by FM (P value, not significant). We conclude that the vented FAN aerobic bottle is comparable to the FM bottle for detection of episodes of yeast infection but has the added benefit of detecting bacteria.     

Controlled evaluation of BacT/alert standard anaerobic and FAN anaerobic blood culture bottles for the detection of bacteremia and fungemia.

FAN medium was formulated to improve microbial recovery, particularly for fastidious microorganisms and for microorganisms causing sepsis in patients receiving antimicrobial therapy. In a controlled clinical evaluation performed at four university-affiliated hospitals, FAN anaerobic bottles were compared with standard anaerobic bottles for yield, speed of detection of microbial growth, and detection of septic episodes. A total of 10,431 blood culture sets were received; both anaerobic bottles of 7,694 blood culture sets were adequately filled with blood. Altogether, 925 isolates were recovered: 557 that were the cause of sepsis, 99 that were indeterminate as the cause of sepsis, and 269 contaminants. More Staphylococcus aureus (P < 0.001), coagulase-negative staphylococci (P < 0.001), Escherichia coli (P < 0.02), and all microorganisms combined (P < 0.005) were recovered from FAN bottles; more nonfermentative gram-negative bacilli (P < 0.05), Torulopsis glabrata (P < 0.001), and other yeasts (P < 0.01) were recovered from standard bottles. Growth of S. aureus (P < 0.001), coagulase-negative staphylococci (P < 0.001), Enterococcus faecalis (P < 0.025), streptococci other than Streptococcus pneumoniae (P < 0.01), and all microorganisms combined (P < 0.001) was detected earlier in standard bottles; growth of more isolates of E. coli (P < 0.05) and anaerobic bacteria (P < 0.01) was detected earlier in FAN bottles. The mean times to detection were 14.2 and 16.1 h for standard and FAN bottles, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pathology of the Glomerulus in Sickle Cell Anemia With and Without Nephrotic Syndrome

Glomeruli from 6 cases of sickle cell disease (SS) with the nephrotic syndrome (NS) were compared histologically and quantitatively with glomeruli from 9 cases of SS, 10 cases of sickle cell trait (SCT), 4 cases of other hemoglobinopathies, all without NS, and normal controls. Five of 6 patients with SS and NS had extensive reduplication of their glomerular basement membranes and mild mesangial proliferation. Similar but milder lesions occurred in SS without NS but not in SCT or controls. Incidental renal disease occurred in 1 patient with SS and NS. Nephrotic syndrome was probably secondary to effects of sickle cell disease. Glomeruli in SS were significantly larger (>70%) than in SCT and controls. Mean total glomerular area per unit area of cortex in SS with normal BUN significantly exceeded that of SCT, which, in turn, was significantly greater than that of controls. Mechanisms for the histologic lesions and hypertrophy of the glomeruli were suggested.     

Identification and localization of G protein subunits in human spermatozoa

Antibodies to alpha and beta subunits of guanine nucleotide regulatory proteins (G proteins) were used to identify which G proteins are present in mature human spermatozoa and to determine their subcellular localization. Immunoblots of membranes from spermatozoa demonstrate the presence of Galphai2, Galphai3, Galphaq/11 and Gbeta35 and the absence of Galphai1, Galpha0, Galphas, Galpha12, Galpha13, Galpha16, Galpha and Gbeta36. Indirect immunofluorescence demonstrates the presence of Galphaq/11 in the acrosome, with the highest proportion in the equatorial segment. Galphai2 is present in the acrosome, midpiece and tailpiece and Galphai3 in the postnuclear cap, midpiece and tailpiece. The Gbeta35 subunit is found mostly in the midpiece, with marginal labelling of the head, tailpiece and the equatorial segment of the acrosome. The distinct pattern of distribution of G proteins suggests that they may couple to receptors or effectors which also have discrete regions of localization in spermatozoa. These highly localized signal transduction pathways may regulate discrete functions, such as activation of the acrosome reaction, fusion with the oocyte and motility.     

Clinical importance of increased sensitivity of BacT/Alert FAN aerobic and anaerobic blood culture bottles.

Two recent multicenter blood culture studies found that BacT/Alert FAN (FAN) bottles (Organon Teknika, Durham, N.C.) had increased yields in detecting bacteremia and fungemia compared with standard BacT/Alert (STD) bottles. Because the clinical importance of this increase in microbial recovery is unknown, we performed a retrospective analysis to determine the frequency with which FAN bottles were the sole means of detecting an episode of bacteremia. There were 1,047 positive blood cultures in which both study bottles were adequately filled and the organism isolated was judged to be the cause of sepsis: 240 (23%) were positive only in FAN bottles and 73 (7%) were positive only in STD bottles. Of a total of 664 episodes of bacteremia, 126 (19%) were identified only by FAN bottles and 43 (7%) were identified only by STD bottles (P < 0.0001). Episodes detected only by FAN bottles more often were recurrent events (23 of 126, or 18%) than episodes detected only by STD bottles (2 of 43, or 5%) (P < 0.05) and more commonly occurred in patients receiving theoretically effective antibiotic therapy (33 of 126 [26%] versus 4 of 43 [9%]) (P < 0.05). The medical records for patients with 127 of these episodes (92 FAN bottles only; 35 STD bottles only) were available for review. More than half of both FAN bottle-only (60 of 92, or 65%) and STD bottle-only (20 of 35, or 57%) episodes were judged to be clinically important. We conclude that FAN bottles improve the detection of bacteremia and that the majority of the additional episodes detected are clinically important. The benefits of the greater yield in specific patient populations must be balanced against the higher costs of FAN bottles.     

Cardiovascular patterns associated with threat and challenge appraisals: a within-subjects analysis

Previous studies demonstrated distinct cardiovascular patterns associated with threat and challenge appraisals for groups of participants. We extend these results by assessing whether appraisals continue to be associated with these cardiovascular response patterns within an individual as appraisals change. Participants completed four verbal mental arithmetic tasks for which they made appraisals before and after each task. Cardiac reactivity and total peripheral resistance (TPR) were calculated for the first and last minutes of each task, and the number of responses and percent correct were measured for each task. In line with our prediction, pretask appraisals were related to some task-related cardiac responses across the four tasks. In addition, task-related cardiovascular reactivity and behaviors both influenced appraisals following the task. Our findings suggest that an idiographic analysis of appraisals, cardiovascular physiology, and task-related behaviors provides a richer understanding of the appraisal process and reveals sex differences deserving further assessment.     

The educational impact of ACGME limits on resident and fellow duty hours: a pre-post survey study.

PURPOSE: To assess the educational impact of Accreditation Council for Graduate Medical Education resident work-hour limits implemented in July 2003. METHOD: All trainees in all 76 accredited programs at two large teaching hospitals were surveyed between May and June 2003 (before work-hour reductions) and then between May and June 2004 (after work-hour reductions) about hours, education, and fatigue. Based on changes in weekly duty hours, 13 programs experiencing substantial reduction in hours were classified into a reduced-hours group. Differences in assessments of educational endpoints before and after policy implementation by trainees in the reduced-hours group were compared with those in other programs to control for potential temporal trends, using two-way ANOVA with interaction. RESULTS: The number of respondents was 1,770 (60% response rate). The reduced-hours group reported a significant decrease in time spent directly caring for patients (from 48.5 to 42.3 mean h/wk, P = 0.03), but the volume of important clinical experiences, including procedures, was preserved, as was the sense of clinical preparedness. On 22 questions related to educational quality and adequacy, only three differences in differences were significant, with the reduced-hours group reporting a relative increase in opportunities for research, decrease in quality of faculty teaching, and decrease in educational satisfaction. The percentage of trainees reporting frequent negative effects of fatigue dropped more in the reduced-hours programs than in the other programs (P < 0.05). CONCLUSION: This study shows that it may be possible to reduce residents' hours--and the perceived adverse impact of fatigue--while generally preserving the self-assessed quality, quantity, and outcomes of graduate medical education.