A comparison of ampicillin/sulbactam versus cefotaxime in the therapy of lower respiratory tract infections in hospitalized patients.

Fifty-three hospitalized patients suffering from lower respiratory tract infections were evaluated in a randomized, comparative trial studying the safety and efficacy of ampicillin/sulbactam (2 g ampicillin plus 1 g sulbactam intravenously every 6 h) versus cefotaxime (2 g intravenously every 6 h). Thirty-four of the 36 and 16 of the 17 patients treated with ampicillin/sulbactam and cefotaxime, respectively, were evaluable. Clinical and bacteriologic efficacy did not differ significantly between the two treatment groups (p = 0.828 and p = 0.648, respectively). Twenty-one (61.8%) of the ampicillin/sulbactam-treated patients were cured, eight (23.5%) improved and four (11.8%) were treatment failures. Nine (56.3%) of the cefotaxime treated patients were cured, four (25.0%) improved and two (12.5%) failed therapy. All primary pathogens were eradicated in 19 (55.9%) of the ampicillin/sulbactam group and were partially eradicated in seven (20.6%) patients. In the cefotaxime treatment group bacteriologic eradication occurred in 10 (62.5%) and partial eradication in two (12.5%) patients. Both study drugs were well tolerated, as the number of adverse reactions in each treatment group was small and similar between the two groups. Ampicillin/sulbactam appears to be as safe and effective as cefotaxime in the therapy of hospitalized patients with lower respiratory tract infections caused by beta-lactamase positive and beta-lactamase negative pathogens.

Ampicillin/sulbactam compared with cefotaxime in the treatment of lower respiratory tract infections of bacterial etiology.

This was a randomized, prospective, parallel study of the efficacy and safety of ampicillin/sulbactam (2 g/1 g) and cefotaxime (2 g), administered intravenously every 6 hours, in 53 hospitalized patients with lower respiratory tract infections. Thirty-four of the 36 patients treated with ampicillin/sulbactam and 16 of the 17 patients treated with cefotaxime were evaluable. Clinical and bacteriologic effectiveness did not differ significantly between the two groups (P = .828, P = .648, respectively). Of the ampicillin/sulbactam-treated patients, 21 (61.8%) were cured, 8 (23.5%) were improved, and 4 (11.8%) were treatment failures. In the cefotaxime group, 9 patients (56.3%) were cured, 4 (25%) were improved, and 2 (12.5%) were treatment failures. All primary pathogens were eradicated in 19 (55.9%) ampicillin/sulbactam-treated patients and partially eradicated in 7 (20.6%); in cefotaxime-treated patients, all primary pathogens were eradicated in 10 (62.5%) patients and partially eradicated in 2 (12.5%). Both study drugs were well tolerated, with the overall incidence of adverse events similarly low in the two groups.

Cefepime as treatment for osteomyelitis and other severe bacterial infections.

Cefepime, a novel, injectable alpha-methoxyimino aminothiazolyl cephalosporin, is active in vitro against many of the Gram-positive and Gram-negative bacteria which cause severe infections, including Pseudomonas aeruginosa. It is more active than existing third-generation cephalosporins against multiply-resistant strains of Enterobacteriaceae because of its low affinity for beta-lactamases and its resistance to hydrolysis by these enzymes. Cefepime retains its high potency of activity against methicillin-susceptible Staphylococcus aureus, coagulase-negative staphylococci and streptococci other than enterococci. Seventy-four patients (46 male and 28 female) were treated with cefepime 2 g i.v. every 12 h; 61 patients were evaluable for efficacy (39 male and 22 female). The infections included pneumonia caused by Gram-negative bacilli (21 patients, six with bacteraemia), septicaemia (seven), pyelonephritis (two), osteomyelitis (23, mainly caused by S. aureus), septic arthritis (four) and soft tissue infections (four, one with bacteraemia). Responses were as follows: 52 (85.3%) patients cured; three (4.9%) improved and six (9.8%) failed. The failures included three patients with osteomyelitis, one with pyelonephritis and two with pneumonia. The pathogens and eradication rates were: S. aureus 23/24 (96%), Staphylococcus epidermidis 4/4, Streptococcus spp. 10/10 (100%), P. aeruginosa 11/14 (79%), Enterobacteriaceae 28/28 (100%), Haemophilus spp. 3/3 and others 7/7. Clinical adverse effects included diarrhoea in 11 patients (14.9%) nausea in five (6.8%) and pruritus in three (4.1%). Laboratory abnormalities included leucopenia in three patients (4.1%) and direct Coombs' conversion in 32 (43.2%). Patients were treated for an average of 31.8 days for osteomyelitis and 11.9 days for other infections.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized clinical study of cefoperazone and sulbactam versus gentamicin and clindamycin in the treatment of intra-abdominal infections.

This report summarizes the experience of investigators in four medical centres who compared the combination of cefoperazone/sulbactam against gentamicin/clindamycin in the treatment of intra-abdominal infections. One hundred and fifty-two patients were enrolled in the study and all were evaluable for safety and tolerance, 110 were evaluable for efficacy. Of the 76 patients (49 male, 27 female) treated with cefoperazone/sulbactam 66 (86.8%) were cured, five (6.6%) improved and five (6.6%) failed to respond to treatment. Of 34 patients treated with gentamicin/clindamycin, 21 (61.8%) were cured, four (11.8%) improved and nine (26.4%) failed. Cure rates for patients receiving cefoperazone/sulbactam were significantly higher than those of patients receiving gentamicin/clindamycin (P less than 0.006). Failures in both groups were attributable in part to pseudomonal and enterococcal infection and abscess formation. The addition of sulbactam to cefoperazone rendered cefoperazone-resistant organisms susceptible to cefoperazone in 11 of the 76 cases (14.4%) and thus permitted treatment with this agent. The present study confirms the safety and clinical efficacy of cefoperazone/sulbactam and suggests that this combination is a viable alternative to an aminoglycoside plus clindamycin for intra-abdominal infections.

Multicomponent nature of the glucosyltransferase system of Streptococcus mutans.

The glucosyltransferases of S mutans 6715 were resolved into two major fractions. One fraction synthesized water-soluble glucans and the other made water-insoluble glucans. Each fraction was found by polyacrylamide gel electrophoresis to be composed of several catalytically active species, apparently glycoprotein in nature. Treatment of the glucosyltransferases with dextranase in the absence of sucrose caused an interconversion of enzyme forms concomitant with a time-dependent loss of enzyme activity, but did not appear to remove significant amounts of the carbohydrate associated with the enzymes. Comparison of enzyme activity patterns on polyacrylamide gels of the five different S mutans serotypes further emphasizes the complexity of the glucosyltransferase system from this group of microorganisms.

Application of fluorescent antibody methods in the analysis of plaque samples.

Direct FA staining for S mutans serotypes may be performed on smears made from plaque or strain isolates and on colonies attached to agar plates of black membrane filters. Staining with single conjugates directed to S mutans serotypes (a to e) as well as with polyvalent a-, b-, d-, f-fluorescein label and c-, e-rhodamine label conjugates indicate that serotype c is the most common. This is in agreement with many reports by other investigators. Cross-reactions with many S mutans conjugates occurred with organisms resembling Lancefield groups C and G streptococci.

Evaluation of excitation light sources for incident immunofluorescence microscopy.

A variety of fluorescent excitation light sources were compared using a standard fluorescein solution or a bacterial conjugate with immunofluorescent microscopy. Quantitative data were obtained with microscope photometric apparatus. Both the quantitative data and comparative conjugate titering suggest that the 450-W xenon arc excited significantly more fluorescence than did the more commonly used 250-W mercury arc or the 100-W halogen lamp. The conjugate could be diluted 4 to 32 times more using the 450-W xenon. Additional advantages of 450-W xenon excitation include sufficient energy of wave lengths between 470 to 490 mm, thus permitting narrow-band excitation resulting in less autofluorescence and the ability to perform fluorescent-antibody procedures without the darkening of ambient room light.

Surface structure of Chromatium okenii and Chromatium weissei.

The outermost structured layer of both Chromatium weissei and C. okenii is composed of a hexagonal array of hollow cone-shaped subunits approximately 25 nm in length and 13 nm in diameter.

In vitro plaque formation by several oral diphtheroids implicated in periodontal disease.

The in vitro plaque-forming ability of oral diphtheroids is not dependent upon the type of sugar incorporated in the culture medium.

Polyphosphate inhibition of growth of plaques formed by streptococci and diphtheroids implicated in oral disease.

Growth of intact bacterial plaques associated with dental caries and peridontal disease is inhibited by some polyphosphates.

X-ray diffraction studies of the sulfur globules accumulated by Chromatium species.

Isolated wet and dried sulfur globules, obtained by osmotic lysis of lysozyme-ethylenediaminetetraacetic acid prepared spheroplasts of Chromatium okenii, C. weissei, and C. warmingii, were studied by polarizing microscopy and X-ray diffraction. When viewed through crossed Nicol prisms, the sulfur globules, whether in the cell or isolated in a pure, wet state, had a characteristic maltese cross appearance. The observation that rotation of the mount did not change the orientation of the arms suggested a symmetrical radial arrangement of the birefringent units. X-ray diffraction patterns of freshly isolated, wet sulfur globules gave two broad and diffuse diffraction rings with maxima at 0.36 and 0.52 nm. This pattern closely resembled the diffraction pattern of liquid sulfur. When allowed to stand in the wet state, the sulfur globules eventually converted into crystalline orthorhombic sulfur after passing through an unstable crystalline phase not previously described by X-ray diffraction. Vacuum drying of the sulfur globules accelerated the change into crystalline orthorhombic sulfur.