Carl Kamme

Aerobic and Anaerobic Bacteria in Deep Infections after Total Hip Arthroplasty: Differential Diagnosis Between Infectious and Non-Infectious Loosening

Five separate biopsy samples for bacterial culture were taken at primary total hip arthroplasty in patients without signs of infection and at reoperation of patients with infectious and noninfectious loosening of the prosthesis. Based on the results of the culture, on serologic results and on the erythrocyte sedimentation rate, bacteria of clinical significance could be distinguished from contaminants. Growth in one or two of five biopsy samples was a strong indicator of contamination, while growth in five of five biopsy samples of one or two bacterial species strongly indicated an infection. These diagnostic procedures are applied to differentiate between infectious and noninfectious loosening of the prosthesis. In the delayed infections, the low-virulent aerobic and anaerobic bacteria Staphylococcus epidermidis, Propionibacterium acnes and peptococci were predominant.

Distribution of diplococcus pneumoniae types in acute otitis media in children and influence of the types on the clinical course in penicillin V therapy

Abstract Pneumococci isolated from the ear exudate in 245 children under 10 years of age afflicted with acute otitis media were typed. Types 3, 6, 14, 18, 19 and 23 were found in 80% of the cases. In the remaining cases, 15 other types were found. Five strains were not typable with the antisera used. Types 14 and 23 were found twice as often in the age group 0-3 years as in the higher age groups, whereas the opposite was true for type 3. The relapse frequency was highest after types 14 and 19 infections. The frequency of residual secretory otitis was highest after type 14 infections. Types 19 and 23 were never found in infections followed by secretory otitis. Patients with type 14 infections, healed or unhealed, showed the same blood group distribution within the ABO and Lewis systems as a normal Swedish population. Penicillin V therapy failed to eliminate the pneumococcal strain from the nasopharynx in 40% of consecutive cases of otitis media. Relapse after penicillin-treated pneumococcal otitis is to be regarded as a new complication of the primary infection and not as a reinfection from the environment.

Bacteraemic Pneumococcal Infections in Southern Sweden 1981-96: Trends in Incidence, Mortality, Age-distribution, Serogroups and Penicillin-resistance

In a survey of pneumococcal blood isolates from patients in Southern Sweden, 560 isolates were found between 1981 and 1996. Between these years, the incidence of pneumococcal bacteraemia increased from 5.2 to 15.2/100,000/y. The eight most common serogroups/types (14, 7, 9, 6, 23, 3, 4 and 19) accounted for > 75% of the isolates, and 96.4% of the isolates were of serogroups/types represented in the present vaccine. A male preponderance (1.17:1) was noted, and the men were younger than the women (mean 57 vs 63 y of age; p < 0.05). The overall case-fatality rate during the period was 19%. Seven isolates with reduced susceptibility to penicillin were noted, all from 1991 to 1996. The increasing incidence of pneumococcal bacteraemia could not be explained by any of the following factors; age or sex of the patients, changes in prevailing serogroups/types, variations in vaccine use, emergence of penicillin-resistance, more liberal indications for blood cultures or improved culture methods.

Increasing Resistance to Penicillin in Streptococcus pneumoniae in Southern Sweden

The susceptibility to penicillin of 6 prevalent pneumococcal types isolated from nasopharynx in 1992 was compared with that of corresponding types from 1980-82. The 6 types or groups, 6, 9, 14, 15, 19 and 23, constituted 78% of consecutive isolates. 19/204 isolates in 1992 were intermediately resistant (MIC 0.12-1.0 mg/l) in comparison with 1/194 from 1980-82 (p < 0.001). Resistant strains (MIC > or = 2 mg/l) were not found. Of group 15, no fewer than 10/31 isolates were intermediately resistant, which may support the clonal origin and spread of penicillin-resistant pneumococci. At least 5.0% of nasopharyngeal isolates are now intermediately resistant to penicillin. This figure is substantially higher than the 2% earlier reported in Sweden.

Clindamycin in Persisting Streptococcal Pharyngotonsillitis after Penicillin Treatment

239 patients with streptococcal pharyngotonsillitis completed treatment with phenoxymethyl penicillin 12.5 mg per kg body weight b.i.d. for 10 days. At examination after completing therapy, throat specimens from 53 patients (22%) yielded growth of group A streptococci of the same. T-type as the initial culture (bacterial treatment failure). 20 of these 53 (38%) had symptoms and signs of tonsillitis (clinical and bacterial treatment failure). 48 of the patients with bacterial failure were randomly allocated to phenoxymethyl penicillin or clindamycin in an open design; 22 of them received a second course of phenoxymethyl penicillin for 10 days and 26 were given clindamycin, 6.5 mg per kg body weight b.i.d. (children) or 300 mg t.i.d. (adults) for 10 days. After completing their treatment, 14 of 22 patients (64%) given phenoxymethyl penicillin harboured the same T-type as in the previous two cultures, while group A streptococci were not recovered from any of the 26 patients receiving clindamycin. In patients with clinical failure after phenoxymethyl penicillin treatment, a new course with this drug is not motivated. In that situation clindamycin seems to be an efficient choice.

Prevention of recurrent acute otitis media in otitis-prone children by intermittent prophylaxis with penicillin

The question whether penicillin V (pcV) given intermittently upon signs of upper respiratory tract infections (URTI) in otitis-prone children might prevent recurrent bouts of acute purulent otitis media (AOM) is addressed. As compared with continuous long-term antibiotic treatment as prophylaxis in otitis-prone children, intermittent administration would reduce the overall consumption of antibiotics. Seventy-six otitis-prone children less than 18 months of age were included in this double-blind, randomized, placebo-controlled multicentre study. Follow-up was from January till June. One hundred and twenty-three episodes of AOM occurred. The number of AOM episodes was reduced by 50% in the children on pcV during URTI episodes as compared with those on placebo. No obvious ecological drawbacks were noted. Thus, the described mode of pcV administration seems to be a rational and safe way to reduce the number of AOM episodes in otitis-prone children.

Intrageneric and Intergeneric Transfer of Branhamella catarrhalis β-Lactamase Production

Intrageneric and intergeneric conjugational transfer of beta-lactamase production to a Branhamella catarrhalis recipient is described. The branhamella donor strains were fresh isolates subcultured onto penicillin-containing media directly from the primary plates. A beta-lactamase positive Moraxella nonliquefaciens served as donor in the intergeneric matings. The substrate profiles of the branhamella and moraxella enzymes were indistinguishable as determined by biological assays. Excessive endonuclease activity did not permit a conclusive characterization of isolated extrachromosomal DNA from the branhamella donors.

Beta-Lactamase Production in the Upper Respiratory Tract Flora in Relation to Antibiotic Consumption: A Study in Children Attending Day Nurseries

The occurrence of beta-lactamase production in Haemophilus influenzae, Branhamella catarrhalis and Moraxella nonliquefaciens was compared in 191 healthy children attending day nurseries in 2 municipalities differing with regard to the prescription rate of beta-lactam antibiotics. A significantly higher frequency of beta-lactamase production was recorded in M. nonliquefaciens isolated in the municipality with the higher prescription rate. A corresponding difference was not recorded for H. influenzae or B. catarrhalis. Approximately 75% of the nasopharyngeal pathogens H. influenzae, B. catarrhalis and Streptococcus pneumoniae, as well as the commensal M. nonliquefaciens, were eliminated and often replaced by other strains of either species over a period of one month. Although none of the children were on antibiotics a substantial proportion of the acquired strains produced beta-lactamase. This suggested that the carrier rate of beta-lactamase producing strains of the respiratory tract is not only related to the effect of recent antibiotic treatment but also to the prevalence of such strains in the population.

Characterization of cell-bound papain-soluble beta-lactamases in BRO-1 and BRO-2 producing strains ofMoraxella (Branhamella) catarrhalis andMoraxella nonliquefaciens

InMoraxella (Branhamella) catarrhalis andMoraxella nonliquefaciens strains isolated from clinical specimens in the south of Sweden two variants of beta-lactamase were distinguished by isoelectric focusing (IEF). The BRO-1 (Ravasio type) enzyme was the most common inBranhamella catarrhalis, constituting about 90% of the beta-lactamase found in this species, while the BRO-2 enzyme (1908 type) was as common as BRO-1 inMoraxella nonliquefaciens. The determinants mediating the production of BRO-1 and BRO-2 were both transferable by conjugation. Cell-bound beta-lactamase from reference strains producing BRO-1 and BRO-2 could be solubilized by papain digestion. The isoelectric point of the solubilized enzymes differed distinctly between BRO-1 (pI 6.5) and BRO-2 (pI 6.9). The molecular species of BRO-1 and BRO-2 released by papain digestion were purified by affinity chromatography with phenylboronic acid agarose gel. They had identical molecular weights of approximately 28,000. Their kinetic constants were indistinguishable for a number of substrates and beta-lactamase inhibitors.

Plasmid-Mediated β-Lactamase in Branhamella catarrhalis

SummaryThe plasmid-mediated β-lactamase in Branhamella catarrhalis (BRO-1), also occurring in Moraxella nonliquefaciens, differs from other known plasmid-mediated β-lactamases in Gram-negative bacteria regarding substrate profile and isoelectric point.B. catarrhalis strains previously reported to produce β-lactamases deviating from BRO-1 were tested, and the β-lactamases did not differ significantly from BRO-1 in substrate profile, isoelectric point or relative substrate affinity index (RSAI). Further investigations of strains of various geographic origin should be undertaken. RSAI seems to be a useful tool for screening of β-lactamases in B. catarrhalis since values for a large number of strains can easily be determined. The previously reported conjugational transfer of BRO-1 production within species B. catarrhalis and from M. nonliquefaciens to B. catarrhalis was confirmed. Four bands of extrachromosomal DNA were regularly detected by agarose gel electrophoresis in β-lactamase-producing as well as in β-lactamase-negative strains of B. catarrhalis and M. non-liquefaciens, provided that the excessive nuclease activity in the preparations was inhibited.