Search PubMed⌕ Search

Biomedical subjects

C G Cobbs

Publications and source records attributed to C G Cobbs.

At least 37 records · Page 2Linked to original sources
PubMed1986

Q fever endocarditis.

Q fever endocarditis, which is seen most often in Great Britain and Australia, has been rarely observed in the United States. A patient with an eight month febrile illness who had signs and symptoms of endocarditis and serologic studies diagnostic of Q fever endocarditis is reported. A history of extensive travel makes it unclear where he originally contracted the disease. Q fever endocarditis is probably underdiagnosed and should be looked for in any case of culture negative endocarditis or chronic fever of unknown origin.

Aged↗
PubMed1986

Pseudallescheria boydii infection of the central nervous system in a cardiac transplant recipient.

We have described a cardiac transplant recipient with fatal Pseudallescheria boydii infection of the central nervous system. Unusual features included meningitis without brain abscess and noncommunicating hydrocephalus due to exuberant growth of the organism in the ventricular fluid. Long-term amphotericin B administration may have played a role in the development of this infection.

Adult↗
PubMed1986

In vitro activity of piperacillin, ticarcillin, and mezlocillin alone and in combination with aminoglycosides against Pseudomonas aeruginosa.

A total of 103 isolates of Pseudomonas aeruginosa were studied to compare the in vitro effectiveness of three beta-lactam antibiotics (piperacillin, ticarcillin, and mezlocillin) when used alone and in combination with four aminoglycosides (tobramycin, gentamicin, amikacin, and netilmicin). All drugs were tested as single agents against a standard inoculum (5 X 10(5) CFU/ml). The three antipseudomonal penicillins were also tested against the isolates at a higher inoculum concentration (10(7) CFU/ml). Synergy testing was performed by the two-dimensional checkerboard method and was defined by a fractional bactericidal index of less than or equal to 0.5 and bacterial killing accomplished at antibiotic concentrations no greater than those achievable in serum. All combinations were assessed for synergy. The degree of synergy was further analyzed by dividing the isolates into groups based on their susceptibility and resistance to the individual agents in the combination. The overall effectiveness of the various aminoglycoside-antipseudomonal penicillin combinations was assessed regarding their ability to kill the isolates either as single agents or through synergy. Piperacillin was the most active antipseudomonal penicillin, and tobramycin and amikacin were the most active aminoglycosides when used as single agents. When tested against isolates at a higher inoculum concentration, ticarcillin was significantly more active than the other beta-lactams. The highest degree of overall synergy was noted with gentamicin-ticarcillin (78.2% of strains) and amikacin-piperacillin (77% of strains). When assessed for overall effectiveness, all combinations containing amikacin were the most active. The combination of amikacin-piperacillin was the most effective, with activity against 96% of all isolates.

Aminoglycosides↗
PubMed1985

Indications for cardiac surgery in patients with active infective endocarditis.

Currently, absolute indications for valve replacement during active infective endocarditis include severe heart failure, the presence of an infecting microorganism that is not susceptible to available antimicrobial agents, and, in patients with an infected prosthetic valve, an unstable device. Relative indications include an etiologic microorganism other than a susceptible Streptococcus, relapse after presumed effective therapy, evidence of intracardiac extension of the infection, two or more systemic emboli, vegetations large enough to be demonstrated by echocardiography, and, in patients with an infected prosthetic device, early disease and periprosthetic leak. With use of data from the medical literature, a study generated by the cardiovascular surgical group at the University of Alabama School of Medicine, and a brief cost analysis, a point system was constructed to assist in decision-making concerning surgery in patients with active infective endocarditis. The usefulness of this system will depend on experience generated from its utilization in a larger number of patients as well as new data relative to a more complete understanding of the risks and benefits of surgery in this condition.

Actuarial Analysis↗
PubMed1985

Cefotaxime aminoglycoside interactions.

Minimum inhibitory concentrations and minimum bactericidal concentrations were determined for cefotaxime, gentamicin, tobramycin and amikacin and for the combination of cefotaxime and each of the aminoglycosides in vitro against 200 strains of Enterobacteriaceae. 91% were susceptible to cefotaxime, 93.5% were susceptible to gentamicin, 89.5% were susceptible to amikacin and 68% were susceptible to tobramycin. There were 95 strains which could be evaluated for synergistic killing by the antimicrobial combinations. Synergism was shown against 78% of strains by cefotaxime and amikacin, against 71% by cefotaxime and tobramycin and against 64% by cefotaxime and gentamicin. In 19 of 22 instances where a bacterial strain was resistant to both cefotaxime and the aminoglycoside, synergistic killing with clinically achievable levels of both antimicrobial agents was demonstrated. There was no significant decrease in concentration of any of the three aminoglycosides after incubation with cefotaxime at 37 degrees C for 0, 4 or 24 h.

Aminoglycosides↗
PubMed1984

Elevated serum D-arabinitol levels in patients with sarcoidosis.

D-Arabinitol has been found in the serum of patients with candidiasis in an incidence varying from 38 to 82%. While screening serum by gas chromatography for the presence of this sugar, we observed elevated concentrations in several patients with sarcoidosis. In an attempt to determine the significance of this chance observation, we tested serum from additional patients with sarcoidosis along with serum from patients with other clinical conditions known to be associated with elevated D-arabinitol levels. Of 53 patients with sarcoidosis, 27 (51%) had elevated concentrations of this compound. Only one of these patients had decreased renal function (creatinine, 2.5 mg/dl). We were unable to correlate elevated values with extent of the disease. Although the significance of this finding is not clear, it may represent a clue to the pathogenesis of sarcoidosis.

Adolescent↗
PubMed1984

Prosthetic valve endocarditis.

Fifty-three (3.6%; actuarially 4.1% at 48 months) of 1465 consecutive in-hospital survivors of valve replacement from 1975 to July 1979 (aortic, mitral, or aortic and mitral, only one untraced) developed prosthetic valve endocarditis (PVE). Incremental risk factors for developing PVE were native valve endocarditis (p less than .0001), black race (p = .0001), mechanical prosthesis (vs bioprosthesis) (p = .005), male sex (p = .04), and longer cardiopulmonary bypass time (p = .09). In general, the hazard function for developing PVE was greatest at 3 weeks after valve replacement. Patients with native valve endocarditis had a tendency to develop PVE early after valve replacement, as did patients in whom mechanical prostheses were used. PVE associated with Staphylococcus epidermidis tended to appear within 6 months of valve replacement, whereas streptococcal PVE tended to appear later after valve replacement. PVE took an atypical form in some patients, but patients with possible PVE (n = 6) had the same findings as those with certain PVE (n = 47). In 11 patients bacteriologic confirmation of PVE was not obtained. The typical prosthetic and periprosthetic characteristics of PVE were present in 30 of the 40 cases in which observations were possible. PVE is a serious condition; 34 (64%) of our 53 patients died. Most deaths occurred within 3 months of the first evidence of PVE. Recovery of some patients is possible with appropriate medical and surgical treatment, but more intense preventive measures are indicated.

Endocarditis, Bacterial↗
PubMed1984

Failure of colchicine in the treatment of Mollaret's meningitis.

A 32-year-old man was hospitalized 23 times in 11 years because of attacks of Mollaret's meningitis. Colchicine (0.6 mg twice daily) was administered for 15 months but failed to decrease the severity or the frequency of attacks. The prophylactic efficacy of drugs in Mollaret's meningitis is difficult to assess because episodes are unpredictable and remissions occur spontaneously. There remains no established therapy for Mollaret's meningitis.

Adult↗
PubMed1983

Interaction of cefotaxime and aminoglycosides against enterococci in vitro.

The antibacterial activities of cefotaxime, gentamicin, tobramycin, and amikacin as well as the combinations of cefotaxime and aminoglycosides were tested against 50 strains of enterococci. Synergy studies were performed by the time-kill method, and with this technique the combination of cefotaxime plus gentamicin appeared to be more active than the combination of cefotaxime plus tobramycin or cefotaxime plus amikacin. Results of this in vitro study suggest cefotaxime and gentamicin may provide some activity against enterococci, although not sufficient to substitute for proven therapy such as penicillin-ampicillin and gentamicin.

Amikacin↗
PubMed1982

Ceftriaxone: in vitro studies and clinical evaluation.

The in vitro activity of ceftriaxone against 437 clinical isolates of gram-negative bacilli was determined. Ceftriaxone was found to have high in vitro activity against Enterobacteriaceae, with the exception of Enterobacter cloacae. Ceftriaxone was only minimally active against Pseudomonas aeruginosa and Acinetobacter calcoaceticus. We evaluated the clinical efficacy and toxicity of ceftriaxone in 55 adult patients. Bacterial infection was confirmed by the isolation of etiological bacteria in 30 patients. Infectious disorders treated included 10 pneumonias, 13 urinary tract infections, and 7 soft tissue or bone infections. Pathogens identified were 25 isolates of gram-negative bacilli, 5 isolates of Staphylococcus aureus, 5 isolates of pneumococci, and 4 isolates of other streptococci. The overall efficacy of ceftriaxone was excellent. The clinical cure rate was 93%, and the bacteriological cure rate was 93%. A total of 30 adverse reactions were noted in 22 of 55 patients receiving ceftriaxone, but only one necessitated discontinuation of treatment. Adverse effects frequently noted were elevated hepatic enzymes (16%), thrombocytosis (16%), and eosinophilia (8%). Ceftriaxone is an effective and well-tolerated antimicrobial agent that appears promising for the treatment of serious gram-negative bacillary infections.

Adolescent↗
PubMed1981

In vitro activity of N-formimidoyl thienamycin (MK0787) against resistant strains of Pseudomonas aeruginosa, Staphylococcus epidermidis, Serratia marcescens, and Enterococcus spp.

The in vitro activities of N-formimidoyl thienamycin (MK0787) and nine other antibiotics were tested against 129 clinical isolates, including 71 of enterococci, 34 of Staphylococcus epidermidis, 17 of Pseudomonas aeruginosa, and 7 of Serratia marcescens. These isolates exhibited a variety of resistant patterns: 97% of the enterococci were resistant to moxalactam; 71 and 81% of the S. epidermidis isolates were resistant to methicillin and penicillin, respectively; 47, 53, and 53% of the P. aeruginosa isolates were resistant to carbenicillin, cefotaxime, and moxalactam, respectively; and all S. marcescens isolates were resistant to amikacin, gentamicin, and tobramycin. With respect to concentrations required to inhibit growth of 90% of the isolates, N-formimidoyl thienamycin was more active than any compound tested. Determination of the concentration required to inhibit growth of 50% of the isolates showed N-formimidoyl thienamycin to be more active than any other agent against S. epidermidis, S. marcescens, and enterococci, but against Pseudomonas isolates it was less active than amikacin, gentamicin, and tobramycin. This preparation is potentially useful for patients with serious infection caused by resistant bacteria; enterococcal and S. epidermidis endocarditis infections may be special situations which merit clinical trials.

Anti-Bacterial Agents↗
PubMed1981

Clinical evaluation of moxalactam.

We investigated the clinical efficacy of moxalactam for treatment of a variety of infectious disorders in 50 patients (38 males and 12 females). Patient ages ranged from 8 days to 98 years, with a median of 66 years. Infectious disorders were confirmed by isolation of etiological bacteria in all patients. Thirty-eight patients had gram-negative bacillary disease, nine had pneumococcal infection, and three had disorders caused by staphylococci or streptococci. Twenty-three patients had pneumonia, 17 had bacteremic diseases other than pneumonia, and 10 had miscellaneous infectious diseases. The overall efficacy of moxalactam was excellent. Forty-eight patients were cured by clinical criteria, and 45 were cured by bacteriological criteria. A total of 19 adverse reactions were associated with the use of moxalactam in 18 patients, but none were severe and only one necessitated discontinuation of treatment. Moxalactam promises to be an important addition to our therapeutic armamentarium, especially for therapy of gram-negative bacillary infections.

Adolescent↗
PubMed1980

Approach to the management of fever and granulocytopenia.

In recent years, advances in chemotherapy for malignant disease have resulted in a greater population of patients with granulocytopenia whose course in often complicated by fever. We reviewed the current medical literature in an attempt to identify the most appropriate management of this special patient population. Our findings suggest that patients with fever and granulocytopenia and without a diagnosis of infectious disease who improve on empiric antimicrobial therapy should continue to receive empiric therapy until their granulocytes recover. Patients in this same category who remain febrile probably do not have an infectious cause of their fever, and discontinuation of empiric antibiotics should be considered if they appear clinically stable. A guideline to the management of these patients is presented.

Agranulocytosis↗
PubMed1980

Pharmacology, tolerance, and antiviral activity of vidarabine monophosphate in humans.

Vidarabine (adenine arabinoside) is a purine nucleoside useful in humans for therapy of herpes simplex virus encephalitis and herpes zoster virus infections in immunocompromised patients. However, the potential usefulness of vidaribine is limited by its poor solubility, which requires continuous infusion in relatively large volumes of intravenous fluid. Vidarabine 5'-monophosphate is highly soluble and has the advantage that it can be administered intermittently intramuscularly or intravenously. In a clinical, pharmacokinetic study, plasma levels and urinary excretion of vidarabine 5'-monophosphate were determined after intravenous and intramuscular administration in 29 immunosuppressed patients with herpes simplex or zoster virus infections at dosages of 15 to 30 mg/kg per day administered for 5 days. As determined by high-pressure liquid chromatography, vidarabine 5'-monophosphate was metabolized in a fashion comparable to the metabolism of vidarabine and its major metabolite in plasma was arabinosyl hypoxanthine. After administration, 40 to 50% of the vidarabine 5'-monophosphate was recovered from the urine as arabinosyl hypoxanthine, and 3 to 4% was recovered as vidarabine. Determinations of areas under the curve for arabinosyl hypoxanthine were not statistically different by dosage for intramuscular or intravenous routes of administration. At all dosages studied, viral clearance appeared to occur with therapy. The advantage of increased solubility will lead to controlled clinical investigations in which vidarabine 5'-monophosphate is administered by intramuscular or intravenous routes against targeted human herpesvirus infections.

Antiviral Agents↗
PubMed1980

Modification of bacterial serum susceptibility by rifampin.

A subinhibitory concentration of rifampin converted a strain of Escherichia coli from serum resistant to serum susceptible. When continually cultured in nutrient broth containing 1.5 microgram of rifampin per ml, this strain of E. coli became susceptible to killing by both normal human serum and normal rabbit serum. Copared to the original strain, the rifampin-treated E. coli displayed no detectable change in adherence capability, but appeared less virulent in the rabbit model of endocarditis. A rifampin-resistant mutant of the E. coli strain was not found to undergo conversion to serum susceptibility upon culture in rifampin.

Animals↗