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Objective: To investigate the impact of the introduction of a consultative service on the use, efficiency of dosing and clinical toxicology of the aminoglycoside antibiotics, gentamicin and tobramycin, in a general hospital., Methods: Two audits were conducted six months and 18 months after the introduction of the consultative service. The audits reviewed the use of drug assay services, the adequacy of drug administration (as measured by serum antibiotic concentrations), indications for prescription, adverse outcomes (by noting markers of nephrotoxicity) and the antibiotic sensitivity of Gram-negative pathogens. The results were compared with the results of an audit conducted before the consultative service was instituted., Results: There was a significant (P < 0.001 by chi 2 test) increase in the use of assays, with drug assays performed in 67% (first audit) and 77% (second audit) of aminoglycoside courses compared with 48.2% in the pre-intervention audit. Sample timing was greatly improved, with more than 70% of the samples collected at the appropriate times. Assay wastage in terms of uninterpretable assay results decreased significantly (P < 0.001) from 42.9% of total assays to 6.3% at the first audit and 3.8% at the second audit. The percentage of assay results in the desirable range increased significantly (P < 0.001) from 39.1% to 71.9% (first audit) and 75.4% (second audit). Pharmacokinetic recommendations were made in 39.1% and 64% of all aminoglycoside courses during the first and second audits respectively, with clinician acceptance of dosage recommendations at 83.1% and 82.8% respectively. For aminoglycoside courses prescribed for therapeutic reasons, 97.9% (first audit, n = 325) and 98.6% (second audit, n = 280) of indications for use were judged as clinically appropriate. The incidence of suspected aminoglycoside-induced nephrotoxicity was reduced from 8.9% of patients to 1.6% (first audit, P < 0.001) and 2.4% (second audit). Bacterial sensitivity audits showed that the great majority of clinical isolates of target organisms (n = 3523, Year 1 and n = 3385, Year 2) were sensitive to gentamicin (92.2% and 91.5% respectively) and tobramycin (98.1% and 98.8% respectively); these aminoglycosides exceeded all alternative agents in effectiveness, including first and third generation cephalosporins., Conclusions: The overall results indicate that introduction of the consultative service had a positive impact on the effective use of aminoglycosides, with a marked decrease in clinical toxicity. These influences were shown to persist for at least 18 months. The availability of reliable predictive techniques to reduce toxicity allows active promotion of aminoglycosides as the agents of choice on grounds of efficacy and economy.

We report an analysis of the results obtained in our first 100 studies with indium-111-oxine labelled leukocyte scintigraphy, a diagnostic technique which has recently become available for clinical evaluation within Australia. We used this technique to assess patients with suspected sepsis or inflammation after other commonly used investigations had failed to confirm a diagnosis. Four patient subgroups were evaluated: fever of unknown origin; suspected abdominal or postoperative sepsis; suspected active inflammatory bowel disease; and suspected sepsis or inflammation of bones or joints. The course of all patients was followed for at least three months to establish the accuracy of the technique. The leukocyte labelling procedure took 90 min and imaging was carried out typically 3-6, 24 and occasionally 48 h after reinjection of the labelled autologous leukocytes. In one patient labelling of leukocytes was unsuccessful. In the remaining 99 studies the overall sensitivity of leukocyte scintigraphy was 88% (36 of 41 patients with a proved inflammatory or infective disease focus had positive scan findings); and the specificity was 95% (55 of 58 cases with no proved disease focus had normal scan findings). This series supports the use of this method as the imaging procedure of choice in nuclear medicine for the evaluation of suspected acute sepsis (symptoms less than four weeks' duration), of inflammatory bowel disease and of suspected infections involving appendicular bones which contain no active bone marrow. It is also a useful secondary scintigraphic procedure, after gallium-67-citrate scintigraphy, in patients with suspected infective disorders of more than four weeks' duration.

Ten cases of campylobacter bacteraemia, which were diagnosed over a three-year period, are described. Four patients presented with acute gastrointestinal illness, three patients had acute febrile illnesses, two patients had cellulitis and one patient presented with ureteric colic. Two patients had lifelong agammaglobulinaemia, two were undergoing corticosteroid therapy and there was one nosocomial infection. In contrast with previous reports, the most common species that was isolated was Campylobacter jejuni, which was found in eight cases, and this includes the first report of cellulitis that was most probably caused by C. jejuni. All of these isolations of campylobacter have occurred since the introduction of the radiometric technique of processing blood cultures.

A comprehensive, multiphasic review of gentamicin and tobramycin utilization was undertaken with audits of the microbiological sensitivity of Gram-negative pathogens; indications for the prescription of aminoglycoside agents; the utilization of assay services; the adequacy of clinical drug delivery by measures of serum antibiotic levels; and the assessment of adverse outcomes by markers of nephrotoxicity. The great majority of clinical isolates of target organisms (n = 4208) was more sensitive to gentamicin (96%) and to tobramycin (99%) than to all alternative agents, including first- and third-generation cephalosporin agents. A review of the indications for the prescription of aminoglycoside agents by clinical criteria showed that in 85.6% of 278 documented cases, the choice of agent was appropriate by clinical and microbiological criteria. In a substantial (77.6%) proportion of the 511 patients who were receiving therapeutic courses of an aminoglycoside agent, serum drug assays had been performed. Assay data could not be interpreted adequately in 52.6% of 3079 assayed cases as a result of inadequate data on administration regimens (39.7%) or sampling regimens (12.9%). Where sampling was documented adequately, there was extreme variation (zero to five hours) in post-dose sampling. In only 33.2% of cases could it be concluded unambiguously that the patients were receiving safer, adequate therapy for clinically significant infections, 5.6% of patients were receiving potentially toxic doses, and 8.6% of patients showed suboptimal concentration profiles. The majority of potentially toxic levels were associated with adverse effects.(ABSTRACT TRUNCATED AT 250 WORDS)

A simple spectrophotometric method was developed to measure serum and urinary methionine concentrations. Serum methionine concentrations of greater than 200 mumol/L were found only in patients who were suffering from severe liver failure. In patients who died because of severe liver failure, a continuing increase in the methionine concentration was associated with a deteriorating mental state, while in patients who recovered the serum methionine concentration remained below 200 mumol/L during the coma stage. Urinary methionine to creatinine ratios above 300 were found only in specimens from patients who died. Sera and urine specimens from patients who were suffering from uncomplicated viral hepatitis showed no increase in methionine concentrations, while sera from patients with renal impairment and urinary specimens from patients who were suffering from chronic active hepatitis showed normal or only mildly elevated methionine concentrations.

Two cases of respiratory syncytial virus pneumonitis in adults area described. In both patients, the clinical picture of the adult respiratory distress syndrome, with marked tachypnoea. hypoxaemia and bilateral diffuse pulmonary infiltrates, was present. One patient had systemic lupus erythematosus, while the other had chronic obstructive lung disease and was a heavy drinker of alcohol. Both patients survived and recovered after a prolonged stay in hospital.