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Previous studies have shown that bacteremia due to vancomycin-resistant Enterococcus species (VRE) is associated with mortality of 17%-100%, but comorbid conditions may have confounded the estimates. We designed a historical cohort study to determine the mortality attributable to VRE bacteremia. Twenty-seven patients with VRE bacteremia were identified as cases. Within 7 days of the onset of bacteremia, severe sepsis developed in 12 patients (44%) and septic shock developed in 10 (37%). Case patients were closely matched to control patients without VRE bacteremia (1:1) by time of hospitalization, duration of exposure, underlying disease, age, gender, and surgical procedure. The mortality was 67% among cases and 30% among matched controls (P = 0.1). Thus, the mortality attributable to VRE bacteremia was 37% (95% confidence interval [CI], 10%-64%) and the risk ratio for death was 2.3 [CI, 1.2-4.1). We conclude that VRE bacteremia is associated with high rates of severe sepsis and septic shock. The attributable mortality approaches 40%, and patients who have VRE bacteremia are twice as likely to die than closely matched controls.

A 62-yr-old woman with a history of mental retardation, paranoid psychosis and agitated depression presented with deterioration in her baseline mental status and fever. No obvious source of fever was found on clinical exam or on initial laboratory studies. An 111In-white blood cell (111In-WBC) study was performed 1 wk after hospital admission, which revealed increased uptake in the anterior neck and oral cavity. Subsequent laryngoscopy revealed a red, swollen epiglottis compatible with epiglottitis. While not advocating 111In-WBC scintigraphy as part of the workup of epiglottitis, this case is presented to emphasize the possible milder presentation of epiglottitis in adults compared to children.

We describe an outbreak of vancomycin-resistant Enterococcus faecium (vanA phenotype) bacteremia on the oncology ward of a tertiary care community hospital. In 10 of the 11 cases the patients had leukemia and were neutropenic (median duration of neutropenia, 21 days) at the time of bacteremia. On average, patients received six antibiotic agents for a total of 61 agent-days prior to development of vancomycin-resistant E. faecium bacteremia. The mortality rate was 73%. Molecular typing of 22 isolates revealed that the majority (83%) represented a common strain, indicating nosocomial spread. When the 11 cases were compared to 22 matched control patients, gastrointestinal colonization with vancomycin-resistant E. faecium (odds ratio [denominator, 0] infinity, P = .005) and the use of antimicrobial agents with significant activity against anaerobes (metronidazole, clindamycin, and imipenem; odds ratio infinity, P = .02) were found to be risk factors for the development of vancomycin-resistant E. faecium bacteremia. Since no proven therapy for such infection exists, there is an urgent need to identify effective measures to prevent and control the development of vancomycin-resistant E. faecium bacteremia.

Chronic necrotizing pulmonary aspergillosis is an indolent, locally invasive form of Aspergillus infection. Treatment options are limited and controversial. Resection is often curative if the patient has sufficient ventilatory reserve. Even though intravenous amphotericin B is effective in a few patients, toxicity limits its use. Aerosolized amphotericin B has proven ineffective. Anecdotal reports of intracavitary and endobronchial antifungal therapy show limited success. Our patient had unresectable chronic necrotizing pulmonary aspergillosis treated successfully with intracavitary instillation of amphotericin B, delivered via the flexible fiberoptic bronchoscope.

The interaction of Legionella micdadei with human polymorphonuclear neutrophils (PMNs) and serum was investigated to determine their roles in host defense against this organism. Serum and PMNs from normal donors having no antibody to L micadei were used. PMNs phagocytized once-agar-passaged (74.6% +/- 6.5%) and twice-agar-passaged (87.3% +/- 1.0%) L micdadei less (P less than 0.05) than L micdadei passaged multiple times on agar (97.5% +/- 1.0%) or Staphylococcus aureus (98.3% +/- 0.5%). Under the same conditions, no phagocytosis of Legionella pneumophila occurred. Use of heat-inactivated serum abolished phagocytosis. PMN killing of once-agar-passaged (1.5% +/- 1.5%) and twice-agar-passaged (0) L micdadei was less (P less than 0.001) than that of L micdadei passaged multiple times on agar (88.6% +/- 4.0%) or S aureus (96.8% +/- 0.5%). L micdadei was not killed by fresh serum, although, in contrast to L pneumophila, it was opsonized by C3. Thus virulent L micdadei is phagocytized, but not killed, by human PMNs, with complement being the major opsonin.

We have presented a case of pneumococcal empyema without evidence of pulmonary parenchymal infection. We postulate that the pleural space was hematogenously seeded from an unexplained pneumococcemia. This manifestation of pneumococcal infection is unusual, particularly since the patient was receiving adequate antibiotic therapy before the radiologic or clinical appearance of the empyema. This emphasizes the need for diagnostic thoracentesis when the clinical situation changes, even after appropriate antimicrobial therapy is begun.

We have recently shown that Legionella micdadei is ingested, but not killed, by human neutrophils. Herein we investigate the role of human monocytes in defense against this organism. Serum and monocytes from normal donors having no detectable antibody to L. micdadei were used. Egg-passaged L. micdadei organisms multiplied inside these monocytes with a peak growth of 2 log units within 12 h. No growth occurred when monocytes were omitted or when sonicated monocytes were used. Electron microscopy 18 h after infection revealed these organisms to be intracellular in normal-appearing phagosomes. When the input multiplicity of L. micdadei was greater than 1 CFU per monocyte, no intracellular growth occurred. When egg-passaged Legionella pneumophila organisms were used, intracellular organisms were found in phagosomes studded with ribosomes at the same time period. Peak intracellular growth of L. pneumophilia occurred by 48 h. L. micdadei activated the complement system and was opsonized by C3. However the use of complement-depleted (heat-inactivated) serum as the opsonic source had no effect on the bacterium's ingestion or growth in the monocyte. Thus, L. micdadei multiples in human monocytes. This entry and growth is independent of antibody or complement. The intracellular locations of L. micdadei and L. pneumophila differ, suggesting different mechanisms for the survival of these two organisms in the monocyte.

We have studied the pattern of membrane binding site redistribution, movement, and reappearance in polarized and nonpolarized human neutrophils using fluorescein and rhodamine-labeled lectins as probes. In suspension, polymorphonuclear leukocytes (PMN) were spherical and displayed a random array of recognition sites for all of the probes. PMN polarized in suspension by 10(-6) M N-formyl-L-methionyl-L-phenylalanine (f-Met-Phe), and PMN attached to substrate accumulated the bound lectin recognition site complex at the uropod (for Con A; 92.0 +/- 0.2% of cells and 91.3 +/- 9.8% of cells, respectively). Glutaraldehyde fixation of neutrophils oriented in a chemotactic gradient prior to lectin addition revealed the innate unbound recognition site array. Unbound Con A recognition sites were clustered at the front of 74.7 +/- 0.8% of cells in a "headlight" pattern, but binding sites for other lectins were distributed randomly around the polarized cell. When bound Con A complexes are swept to the tail of the polarized living PMN, "new" unbound Con A binding sites appear at the front of the cell. Neither cycloheximide nor KCN nor colchicine interferred with new binding site appearance. Cytochalasin B and sodium iodacetate prevented PMN polarization and interfered with appearance of new receptors. This suggests that these fresh sites are uncovered, previously cryptic binding sites rather than newly synthesized structures. Lectin binding site topography and movement are related to the functional state of the PMN. Since both Con A and certain bacteria bind to mannose derivatives, we postulate that the "headlight pattern" and uncovering of fresh binding sites aid the PMN in engulfing organisms as the phagocyte moves forward.

In a 33 year old man with no discernible immunologic defect, invasive aspergillosis developed in both the pericardium and lung with marked granulomatous reaction. The patient received 2 g of intravenous amphotericin B over eight weeks, with partial regression of the pulmonary infiltrate and disappearance of symptoms. However, five months later, he returned with marked progression of his disease. Evaluation of host defense, including granulocyte and lymphocyte function, was normal. The patient was given an additional 3g of amphotericin B over nine weeks with marked improvement in symptoms and chest roentgenogram. At six-month follow-up, he was asymptomatic with a stable radiographic appearance. A recurrence in symptoms and the pulmonary infiltrate was noted two months later. He was treated with an additional course of amphotericin and currently is receiving ketoconazole in hopes of suppressing the infection. We could find no immune impairment to explain the severe pulmonary and pericardial disease due to Aspergillus flavus in this young man.

Metastatic bacterial endophthalmitis has been reported infrequently in the antibiotic era. We recently encountered five cases of metastatic bacterial endophthalmitis during an eight-month period. The diagnosis was made by blood culture in four of the cases and a positive vitreal aspirate in the fifth case. The organisms included: Staphylococcus aureus, Streptococcus pneumoniae, and groups G and B streptococci. Underlying diseases included endocarditis, lymphoma, and facial trauma. One patient had no identifiable source of infection. The diagnosis was delayed in two of the patients, despite early ophthalmologic consultation. The outcome was poor, four of the five patients lost all useful vision. Development of eye symptoms in the setting of gram-positive bacteremia should be suggestive of this entity. An aggressive diagnostic and therapeutic approach with intravitreal antibiotics might improve the outcome. Our observation of five cases during eight months in one hospital suggests that metastatic endophthalmitis may be more common than is generally appreciated.

The effects of cyclosporin A (cyA) on human polymorphonuclear leukocyte function, including phagocytosis, its associated metabolic burst, bacterial killing, and chemotaxis, were evaluated. Both Pseudomonas aeruginosa and Staphylococcus aureus were used as test particles. Polymorphonuclear leukocytes incubated in 10 and 50 micrograms of cyA per ml behaved normally with respect to phagocytosis and hexose monophosphate shunt activity at both high (10:1) and low (2:1) S. aureus/leukocyte ratios. With a small bacterial inoculum, killing of S. aureus was slightly impaired at early times only in the presence of 50 micrograms of cyA per ml. Phagocytosis and killing of P. aeruginosa with both large and small bacterial inocula were unaffected by cyA. Chemotaxis was within normal limits under all conditions. In addition, polymorphonuclear leukocytes from four renal transplant recipients receiving both cyA and prednisone demonstrated normal metabolic bursts and bacterial killing with both small and large inocula of S. aureus.

The roles of the classical and alternative pathways of complement activation and of antibody in the phagocytosis of Legionella micdadei by polymorphonuclear leukocytes were studied. Normal serum was treated with the appropriate chelators or with heat to inactivate the classical, alternate, or both pathways of complement activation. Normal and complement-depleted sera with or without antibody were employed as opsonins for L. micdadei in phagocytosis assays. There was no difference in the phagocytosis of L. micdadei promoted by normal serum and either C4-deficient serum or serum in which the classical pathway had been inactivated. Both normal and classical pathway-deficient sera promoted significantly greater phagocytosis than did sera in which the alternate pathway or both the alternate and classical pathways had been inactivated. Thus, polymorphonuclear leukocyte phagocytosis of L. micdadei in the absence of antibody required an intact alternate pathway. Specific antibody partially restored opsonization to sera deficient in the alternate or both complement pathways, but phagocytosis was still significantly less than that with the alternate pathway intact.

Polymorphonuclear neutrophils (PMN) can recognize, engulf and kill microorganisms and are thus an important host defence against infection. The initial encounter between a microbe and the neutrophil takes place at the neutrophil surface. Receptors, including those for the Fc end of the immunoglobulin G (ref. 1), the C3b component of complement, formyl peptides and plant lectins have been identified on the surface of neutrophils. We have now examined the surface pattern and arrangement of receptors for the plant lectin concanavalin A (Con A) to determine if the surface receptor array varied with the functional state of the neutrophil. We found that receptors for Con A clustered at the front of polarized neutrophils.