Acta pathologica et microbiologica Scandinavica. Supplement最新文献

Escherichia coli strains isolated from human blood obtained from 539 different patients all over Denmark were examined serologically for O and H antigesn. 425 strains could be O grouped with O sera 1 to 150. 90 strains were spontaneously agglutinable. Using O sera to the ten most frequent O groups: 2, 4, 6, 75, 9, 8, 18, 7, 22 and 1, 57 per cent of all strains could be grouped. Using sera corresponding to the ten most frequent O and the ten most frequent H sera, it was possible to O:H type 68 per cent of all O groupable strains. The K1 antigen was detected in 18 per cent of the strains.

The cellular fatty acids of seventeen Acinetobacter strains were determined. Most acids identified were previously found in neisseriae and moraxellae. Specific for Acinetobacter was 2-hydroxydodecanoid acid and a few minor unidentified components. The fatty acid data were analysed by numerical methods and compared with previous results obtained for neisseriae and moraxellae. The findings were consistent with genetic evidence for some affinities of genus Acinetobacter to genus Moraxella and "false neisseriae". Occasionally, a high resemblance in fatty acid pattern was demonstrated between a Moraxella strain and certain strains of Acinetobacter, and also between an Acinetobacter strain and certain "true neisseriae". Still, the acinetobacters constituted one single cluster separated from the other genera of Neisseriaceae.

The simultaneously occurring mucoid (M) and non-mucoid (NM) variants of Pseudomonas aeruginosa frequently observed in cultures from the respiratory tract of chronically infected cystic fibrosis patients have been studied. M cultures in vitro were unstable and easily dissociated NM colonies. In a large proportion of the cases, M and NM variants occurring simultaneously in cultures from one and the same clinical specimen were of the same pyocine type, phage type, and serogroup. In some remaining cases there were small differences between the M and NM variants such that identity between the variants from one and the same specimen was possible, although not definite. The NM dissociants from M strains were of the same type as the M variant. The possible role of cross-infection and the interaction of bacteria and host response factors continuously tending to select the unstable M variant in vivo are discussed.

The relative prevalence of mucoid strains compared with non-mucoid strains of Pseudomonas aeruginosa has been investigated in all routine bacteriological specimens received in a department of clinical microbiology during 1973. Pseudomonas aeruginosa was isolated from 1054 of the specimens (5.7 per cent) representing 53 patients with cystic fibrosis (551 isolates) and 169 patients with other diseases (503 isolates). The relative prevalence of mucoid strains was significantly higher in specimens from patients with cystic fibrosis (80 per cent) than in specimens from patients with other diseases (3 per cent). Considering patients without cystic fibrosis, the relative prevalence of mucoid strains was low in specimens from all anatomical regions, and no special preference of these strains for the respiratory tract could be demonstrated in these patients, in contrast to the situation in patients with cystic fibrosis. Alternation between mucoid strains and non-mucoid strains in subsequent specimens was observed in 33 of the patients.

In Denmark and probably in other countries as well, the infectious agent causing intercurrent death of rabbits by passages of Nichols pathogenic Treponema pallidum has been studied in rabbits in the absence of T. pallidum. This agent can be propagated in rabbits at intervals of 2 to 30 days and, depending on the interval between passages and the number of passages, the mortality may vary from zero to almost 70 per cent. Based on the post mortem findings in fatal cases, the name pleural effusion disease is suggested for this rabbit infection. Iridocyclitis, haematological and biochemical changes are signs of the disease not described previously. The source of the infectious agent is discussed.