Volume 3 Number 1
respiratory infection in 1 patient in 4, urinary infection in 1 person in 8, and fatal meningitis in 8 patients in the intensive care section of a neurosurgical unit. Isolation of infected persons and the use of large doses of colistin were ineffectual, but complete withdrawal of antibiotics used for both prophylactic and therapeutic purposes brought about a dramatic fall in Klebsiella infection without obvious disadvantage to those that were infected. Other infection showed considerable reduction. The authors recommend that the use of antibiotics should be based on the clinical state of the patient and not just on a positive bacteriological report. PRICE, D. J. E., and SLEIGH, J. D. (1970), ' Control of Infection due to Klebsiella aerogenes in a Neurosurgical Unit by Withdrawal of all Antibiotics', Lancet, 2, 1213.
Virulence of Staphylococcus Aureus A variant of Staphylococcus aureus which had lost an antigenic component (antigen 17) and acquired another (antigen 1) was found to be much less virulent, on tests by intracerebral inoculation of mice, than the parent strain; death was rapid and thought to be due to a toxin. Intracerebral inoculation of mice (groups of six) is considered by the authors to be an effective test for virulence of staphylococci, correlating well with the clinical details of the source from which strains were isolated. Only 18 out of 100 recently isolated strains were avirulent by this assessment. There was a correlation between the numbers of mice killed by a strain and the a-haemolysin titre. TORRES PEREIRA, A., and GOLDBERG, S. S. (1970), 'Virulence of Staphylococcus aureus tested by lntracerebral Inoculation into Mice ', J. reed. Microbiol., 3, 546.
Postoperative Gas Gangrene A patient with gas gangrene following operation on the kidney recovered after treatment by incision of the wound, local instillation of penicillin and sodium hypochlorite, systemic administration of penicillin, spiramycin, and a tetracycline, intravenous injection of polyvalent clostridial antitoxin, and frequent irrigation of the wound with hydrogen peroxide. BITTNER, J., RACOVIT.g., S., GIRDA, S., and ARDELEANU, J. (1970), ' C o m b i n e d Therapy in Postoperative Gas Gangrene ', J. reed. Microbiol., 3, 325.
Contamination from Expiratory Pipe of Ventilator Experiment showed that deliberate contamination of the expiratory pipe as far as possible from the patient was followed by arrival of the bacteria used in models of the patient. On average, this took about 30 hours of continuous use but in 25 experiments contamination took from 6 to 56 hours to occur; in only 1 did it fail to occur within 56 hours. These periods contrasted with the 20 minutes or so that bacteria in the inspiratory pipe took to reach the patient. Filters on the expiratory side are likely to become clogged by moisture, whereas changing the expiratory pipe every 6 hours would be simple and should be effective. BABINOTON, P. C. B., BAKER, A. B., and JOHNSTON, H. H. (1971), ' Retrograde Spread of Organisms from Ventilator to Patient via the Expiratory L i m b ' , Lancet, 1, 61.
Intestinal Carriage of Pseudomonas Aeruginosa Bacteriological examination of intestinal contents taken from 100 patients at necropsy showed the presence of Pseudomonas aeruginosa in 36 per cent of the patients. In patients who had been treated with oral antibiotics the proportion was 43 per cent and in those who had had gastro-intestinal operations it was 53 per cent. Of 10 ileostomy fluid samples, 73 per cent contained Ps. aeruginosa, and it was considered that patients with enterostomies present a special hazard of cross-infection with this organism. In contrast with the high levels shown by these samplings, 5 per cent of 50 normal subjects, 14 per cent of 103 out-patients, and 18 per cent of 240 in-patients yielded Ps. aeruginosa from single faecal specimens. STOODLEY, B, J., and THOM, B. T. (1970), ' Observations on the Intestinal Carriage of Ps. aeruginosa ', J. med. Microbiol., 3, 367.
Pseudomonas Aeruginosa and Newborn Babies Although the subject of this article is a far cry from injuries and their effects, its lesson is of continuing importance: cetrimide is easily contaminated with Pseudomonas and is then a means of cross-infection, as are articles in common use. COOKE, E. M., SHOOTER, R. A., O'FARRELL, S. M., and MARTIN, D. R. (1970), 'Faecal Carriage of Pseudomonas aeruginosa by Newborn Babies ', Lancet, 2, 1045.
Sequelae of Tetanus Twenty-five of 45 patients with tetanus were examined from 2 months to l l years after recovering from the illness. Twenty per cent complained of irritability, 24 per cent noticed that sleep had become disturbed, 20 per cent had fits, and another 20 per cent had myoclonus without fits; in 2 cases there was loss of consciousness without jerking. Two patients had slight difficulty with the sphincters of the bladder and 3 lost their usual libido. This symptom alone showed no tendency to improve. Electro-encephalography gave l0 normal results among which were 4 persons that developed myoclonus. Eight of 21 persons with abnormal tracings had fits but none had the electrical characteristics of epilepsy. These after-effects of tetanus were ascribed to the suppression by the disease of inhibitory synapses although it was recognized that induced paralysis might play a part in some cases. ILLlS, L. S., and TAYLOR, F. M. (1971), ' N e u r o logical and Electroencephalographic Sequelae of Tetanus ', Lancet, 1,826.
Ward Design and Postoperative Wound Infection The study occupied 4 years, of which 2 passed while the unit was in an old block, using an open ward without special arrangements for ventilation, and 2 after moving into new premises. Part I dealt with infection in the ward in a series of just over 1000 patients and part II with 1000 ' clean ' operations that provide useful evidence about the effect of new operating conditions on subsequent infection. The new ward had 40 per cent of its beds in single rooms and there was controlled ventilation. The principal finding was that infection of wounds was 55 per cent lower in the new premises than the old and that crossinfection was reduced by 75 per cent. This was