Hospital cross infection studies on Klebsiella aerogenes

The purpose of this study was to assess the role of upper respiratory and faecal carriage of Klebsiella as potential sources of infection in hospital patients. Weekly nose, throat and rectal swabs were taken from all patients and attendants in Wards 6 and 7, and ward dust and bedding sampled, to trace the sources of infection due to Klebsiella occurring in these wards. Nose and throat swabs were plated directly on to Blood and MacConkey agar and rectal swabs were sub-cultures from overnight Selenite broth suspensions. All positive cultures from any of the above sources were serotyped and biotyped and antibiotic resistance patterns done. The average incidence of commensal Klebsiella carriage in the two wards was 23 percent in throat swabs and 48 percent in rectal swabs, and the incidence rose with duration of hospital stay. Eighteen infections due to K. aerogenes occurred in the two wards under the period of study and 8 of these were due to autoinfection from organisms already present in the faecal flora (7 cases) or upper respiratory tract (1 case). Only 1 case of cross infection occurred in 18 weeks of study. It was assumed that autoinfection was the single most important factor in establishing Klebsiella infection. To investigate this further, 70 cases of Klebsiella infections from different wards were studied for carriage of the infecting serotype and biotype. This was present in the infected patient in 1.4 percent of nasal swabs, 14 percent of throat swabs and 38 percent of rectal swabs. Autoinfection by faecal flora therefore seems to be important in establishing infections due to Klebsiella organisms (AU)

The effect of antibiotic therapy in establishment of infection by the klebsiella species

The use of antibiotics has been claimed to be one reason for the increasing prevalence of gram-negative organisms. 200 patients from whom Klebsiella sp. were isolated had an antibiotic history taken at the time of first isolation of Klebsiella. These were compared with a control group of patients matched for number of days of hopitalisation, ward distribution, age and sex, who showed no evidence of Klebsiella infection. A significant number of the Klebsiella group had been on antibiotic therapy for seven days or longer compared with the control group. The incidence of prescription of antibiotics was much the same in the two groups. This suggest that prolonged antibiotic therapy predisposes to Klebsiella infection(AU)

A biochemical survey of Klebsiella strains isolated in Jamaica

A historical review is made of the literature from 1882, relevant to the classification and biochemical nomenclature of the Klebsiella genus. Details of the development of the more important biochemical tests contributing to the better classification of this genus are given. The work comprises a biochemical survey of 300 isolates from clinical material cultured in the Department of Microbiology, University of the West Indies, from January to June 1966; all the isolates included in this series conformed to the definition of the family Enterobacteriacae and to the genus Klebsiella. 29 biochemical tests were done on all isolates and 288 of the 300 cultures are classified as K. aerogenes or as showing biochemical deviations from the typical K. aerogenes pattern. No strains of K. ozaenae or K. rhinoscleromatis were encountered. There was no association between the source of isolation of the specimens and their biochemical characteristics on the basis of the 29 tests applied. Certain biochemical tests such as fermantation of starch, inositol, cellobiose and adonitol, showed a decrease in the proportion of positive tests in the biochemically aberrant strains, and this difference, when compared to typical strains was statistically significant. A close similarity is shown between the overall biochemical characteristics of groups of Klebsiella strains studied recently in the United States and the strains studied isolated in Jamaica. The need for an internationally-accepted terminology for the biochemical species within this genus is emphasised. (AU)

A review of staphylococcal infections in the University Hospital of the West Indies

The incidence of staphylococcus pyogenes infection in University Hospital, Jamaica, in 1965, is reviewed. The degree of resistance to the five most commonly used antibiotics is compared for in-and out-patient strains. It is noted that the degree of chloramphenicol resistance here is much common in the Nursery and Obstetrics wards. There has been no absolute increase in staphylococcal infection in the last 4 years (AU)