Search PubMed⌕ Search

Biomedical subjects

J T Mader

Publications and source records attributed to J T Mader.

At least 91 records · Page 5Linked to original sources
PubMed1985

Animal models of osteomyelitis.

Clinical research involving osteomyelitis is difficult because of the multiple variables found in the disease process. In order to evaluate osteomyelitis critically, a more precise staging system is needed, along with reproducible animal models for each of the clinical stages. The current animal models for osteomyelitis include the rabbit models of Norden and Andriole, the rat model of Zak, and the dog models of Fitzgerald and Deysine. Although each animal model of osteomyelitis has certain advantages and limitations, they have provided us with a clearer understanding of this disease process and what forms of treatment may prove satisfactory.

Animals↗
PubMed1985

Cost containment through therapeutic substitution of aminoglycosides.

A therapeutic substitution policy (TSP) for tobramycin and gentamicin sulfate was implemented at the University of Texas Medical Branch (UTMB). The policy was designed by various physician-chaired hospital committees and clinical departments that collaborated with the pharmacy service. The goal was to encourage the medical house staff to use the most economical yet safe and effective aminoglycoside, without limiting the medical team's prerogative to select among alternatives within this antibiotic group. Cost data from the first 6 months of aminoglycoside use under the new policy projected an annual savings of $139,071 in drug expenditures and $242,472 in patient charges. Following the implementation of the TSP, a concurrent drug utilization review (DUR) was performed in 50 consecutive inpatients prescribed amikacin, tobramycin, or gentamicin sulfate. The objectives were to identify those aspects of prescribing and monitoring of aminoglycosides by house staff that could be improved by specific policy and/or education, and to evaluate those specific cases in which attending physician's approval allowed house staff to prescribe an aminoglycoside other than designated in the TSP. The audit revealed that house staff were compliant with 72% of the DUR criteria; however, at least one instance (mean of 5.04 +/- 2.21) of noncompliance occurred during the treatment of each patient. The most frequently encountered deficiencies were failure to monitor for ototoxicity, incorrect orders for at least one set of serum aminoglycoside concentrations, and improper dosage adjustments for those patients with renal insufficiency. In three cases, the attending physician approved house staff use of tobramycin instead of gentamicin sulfate for reasons of organism resistance, pre-existing renal impairment, and long-term treatment of osteomyelitis.

Aminoglycosides↗
PubMed1985

Indium-111 chloride imaging in chronic osteomyelitis.

Sixty-eight patients with clinically suspected chronic osteomyelitis were studied with [111In]chloride. Fifty-four images were categorized as true positive; seven were categorized as true negative. There were four false-positive studies, two of which were associated with healing cancellous bone grafts. There were three false-negative studies in patients previously treated with long-term antibiotic therapy. Images in eight noninfected healing fractures 3 to 8 mo old were normal. Three patients with infected total hip prostheses had positive images. Two patients with loose prostheses had negative images. This study shows that [111In]chloride imaging is an accurate way to localize chronic osteomyelitis and may overcome some of the disadvantages of [67Ga]citrate such as localization in noninfected healing fractures and in some loose [67Ga]citrate such as localization in noninfected healing fractures and in some loose prostheses.

Adolescent↗
PubMed1985

Indium-111 chloride imaging in the detection of infected prostheses.

Thirty-three patients with painful joint prostheses and a suspicion of infection were imaged with [111In]chloride. A final diagnosis was established by culture in 19. Of these, 12 were categorized as true positives and three as true negatives. There were two false-positive studies, occurring in patients with knee prostheses. In both, the culture was obtained by aspiration. Two false negatives were in patients with hip prostheses, one of whom had been on long-term antibiotic suppressive therapy. The sensitivity was 86%, specificity 60%, and accuracy 79%. Seventeen of the proven cases had bone imaging prior to [111In]chloride imaging. All 17 static images were positive and were not helpful in differentiating loosening from infection. Using increased uptake on the blood-pool image as a criteria for infection, the sensitivity was 89%, but the specificity was 0. Adding flow studies made little difference in interpreting the blood-pool images. This study shows that [111In]chloride accurate in evaluating infection in prosthesis than bone imaging.

Adult↗
PubMed1985

Methicillin-resistant Staphylococcus aureus osteomyelitis.

In five patients, the diagnosis of methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis was made by clinical and roentgenographic methods and confirmed by bone biopsy cultures. The treatment was staged according to the anatomic setting of the infection and the systemic and local competence of the host. Seven episodes of osteomyelitis were encountered in the five patients. Two patients had persistence of their infection and were successfully treated by additional surgical debridement, antibiotics, and adjunctive hyperbaric oxygen. Vancomycin was administered to all patients. The daily dosage of vancomycin ranged between 100 mg and 2.0 gm. The length of vancomycin therapy ranged from 19 to 56 days. Five of seven biopsy specimens grew bacterial organisms in addition to MRSA. The MIC of vancomycin for MRSA ranged between 0.39 and 1.56 micrograms/ml. Osteomyelitis was arrested in five of seven episodes, and follow-up evaluations ranged from two to 35 months. Two of five (40%) patients receiving the combination of vancomycin and tobramycin developed signs of renal toxicity. Renal function returned to normal after discontinuation of the antibiotics. MRSA osteomyelitis is usually acquired by spread from a contiguous focus of infection and is often polymicrobic in nature. Treatment with vancomycin or vancomycin plus tobramycin when the infection was polymicrobic was effective. The combination of vancomycin plus tobramycin is potentially nephrotoxic.

Adult↗
PubMed1984

Cefmenoxime therapy in bacterial osteomyelitis.

Cefmenoxime, a new parenteral beta-lactamase-resistant cephalosporin, was evaluated for safety and efficacy in 15 patients (10 male and five female) with acute (1 patient) and chronic (14 patients) osteomyelitis. Diagnosis was made by culture of the surgical biopsy specimen. Osteomyelitis was treated with 8 to 12 g of cefmenoxime per day (mean 9.1 g) for 42 to 66 days (mean 47.3). Staphylococcus aureus was the most frequently isolated organism. Minimum inhibitory concentrations (MICs) of cefmenoxime were determined and all pathogens were inhibited by 12.5 micrograms/ml or less, except for Enterobacter cloacae and Acinetobacter species, both of which had an MIC of 25.0 micrograms/ml. All patients had at least one surgical debridement. Of the 15 patients, 10 (67 percent) had the osteomyelitis "arrested." These patients have been followed up five to 14 months after completion of cefmenoxime therapy. Toxicity studies indicated mild elevations in serum glutamic oxalacetic transaminase and serum glutamic pyruvic transaminase in two patients. Cefmenoxime appears to be a safe and effective antibiotic in the treatment of osteomyelitis.

Adolescent↗
PubMed1984

Recurrent diffuse osteomyelitis involving the mandible.

This report describes a case of osteomyelitis that did not respond to routine hyperbaric oxygen, surgical debridement, and intravenous antibiotics. The multiple sites of the osteomyelitis, the presence of skin lesions, and the unusual organism (Corynebacterium group JK, L form) that was isolated indicated that the patient might have an immunodeficiency, but none could be identified.

Adult↗
PubMed1984

Concentrations of vancomycin in bone and serum of normal rabbits and those with osteomyelitis.

The concentrations of vancomycin in the bone and serum of rabbits with Staphylococcus aureus osteomyelitis were assessed after each rabbit was given a single dose of vancomycin. Simultaneous mean concentrations of vancomycin in infected rabbits 1 h after administration of the antibiotic were 36.4 +/- 4.6 micrograms/ml (serum), 5.3 +/- 0.8 microgram/g (infected bone), and 3.0 +/- 0.2 micrograms/g (noninfected bone). Concentrations of vancomycin in serum of normal controls were higher than concentrations of vancomycin in serum of osteomyelitic rabbits after 1, 2, 3, and 6 h.

Animals↗
PubMed1984

The principles of the use of preventive antibiotics.

Antibiotic prophylaxis is indicated only under specific surgical settings. Appropriate antibiotic prophylaxis must take into account the type of surgery, the competence of the host, and the pharmacologic properties of the antibiotic(s). The antibiotic should be given before the surgical procedure and have an antibacterial spectrum that covers the majority of the bacterial organisms anticipated at surgery. If there is doubt about the efficacy, antibiotic prophylaxis should not be initiated.

Animals↗
PubMed1982

Malignant external otitis. Cure with adjunctive hyperbaric oxygen therapy.

Malignant otitis externa developed in a 55-year-old man with diabetes. This Pseudomonas aeruginosa infection was refractory to high-dose moxalactam disodium therapy, despite sufficient in vitro tube dilution sensitivity results. When adjunctive hyperbaric oxygen therapy was added to the treatment regimen, the infection resolved.

Cephamycins↗
PubMed1982

Cefotaxime treatment in patients with osteomyelitis and septic arthritis: a multicenter study.

The effectiveness of parenteral cefotaxime in the treatment of adults with acute septic arthritis or acute or chronic osteomyelitis was evaluated in a multicenter trial. The drug was given to 47 patients admitted to the University of Texas Medical Branch Hospitals or Hahnemann Medical College and Hospital (UT-H study) and to 40 patients in other medical centers using an identical protocol. In the UT-H study, cefotaxime was effective in 15 of 16 patients (94%) with acute osteomyelitis, in 24 of 27 patients (89%) with chronic osteomyelitis, and in four of four patients (100%) with acute septic arthritis. In the multicenter study, the success rates were as follows: acute osteomyelitis, six of six (100%); chronic osteomyelitis, 14 of 19 (74%); and septic arthritis, 12 of 15 (80%). The antibiotic was well tolerated in most patients. The most serious side effect was significant neutropenia, which occurred in three patients. Cefotaxime appears to be a clinically useful, broad-spectrum antibiotic for bone and joint infections.

Adult↗
PubMed1980

A mechanism for the amelioration by hyperbaric oxygen of experimental staphylococcal osteomyelitis in rabbits.

Although hyperbaric oxygen (HBO) is as effective as cephalothin against osteomyelitis due to Staphylococcus aureus in the rabbit, the effect is not by directing killing. To investigate the mechanism, argon washouts (perfusion) and oxygen tensions were measured by intramedullary probes placed in the metaphyses of infected and uninfected tibias. In vitro phagocytic killing activity for S. aureus was determined at oxygen tensions found in these bones under ambient and HBO conditions. Mean tibial oxygen tensions (mm Hg) under ambient conditions were 21 (infected) and 45 (uninfected); under HBO conditions, 104 (infected) and 321 (uninfected). Perfusion was decreased in osteomyelitic bone and was not acutely increased by HBO in either normal or infected bone. Phagocytic killing of S. aureus was markedly decreased at 23 mm Hg of O2, significantly improved at 45 and 109 mm Hg, and most effective at 150 mm Hg. Thus, in osteomyelitic bone, HBO increased intramedullary oxygen to tensions consistent with normal phagocytic function.

Animals↗