The impact of laboratory closing times on delay of adequate therapy in blood stream infections.

BACKGROUND: Patients with bloodstream infections need early adequate antimicrobial treatment to reduce mortality. This raises the question of timing and logistics. How important is the time of day when a culture is flagged positive to the processing of blood cultures and optimisation of antimicrobial therapy? METHODS: We performed a retrospective study assessing the time delay of a positive blood culture result during and after office hours and its impact on adequate antimicrobial therapy. Process duration from the moment of culture positivity to Gram stain completion was compared at different timepoints during the day in a medium-sized hospital with an offsite microbiological laboratory. RESULTS: Ninety-four patients with positive, noncontaminated blood cultures were included. Sixty-six patients (70%) received adequate empirical therapy; this increased to 76 cases (82%) and to 88 cases (95%) after analysis of Gram stain results and complete determination, respectively (p < 0.05 for all comparisons). Median duration from culture positivity to Gram stain completion (including offsite culture transport) increased from a median of four to 12 hours if time of cultures turned positive after office hours (p < 0.05), irrespective of the adequacy of empirical coverage. This also resulted in a median 12-hour delay for the complete process from time of culture positivity to administration of the antimicrobial drug (p < 0.05). CONCLUSION: Processing blood cultures after office hours is often deferred, which can lead to a delay in adequate antimicrobial therapy for patients with bloodstream infections.

[The rise in fluoroquinolone-resistant Neisseria gonorrhoeae among people attending the Municipal Health Service's clinic for sexually transmitted diseases in Amsterdam, the Netherlands; cefotaxime now first-choice treatment for uncomplicated gonorrhoea]. / Toename van fluorochinolonresistentie bij Neisseria gonorrhoeae onder bezoekers van de soa-polikliniek in Amsterdam; cefotaxim nu als eerste keus aanbevolen voor ongecompliceerde gonorroe.

OBJECTIVE: To report the incidence of gonorrhoea and the development of resistance to Neisseria gonorrhoeae among attendees at the Municipal Health Service's STD-clinic in Amsterdam, The Netherlands, 2000-2003. DESIGN: Descriptive. METHOD: Urethral or cervical swabs for culture for N. gonorrhoea were taken from attendees at the STD-clinic. Depending on reported sexual techniques throat and rectal swabs were also taken. The disk diffusion technique in combination with a beta-lactamase test were used for sensitivity testing. RESULTS. The number of Neisseria gonorrhoeae (NG) isolates collected at the Amsterdam Municipal Health Service's STD-clinic decreased from 1047 in 2002 to 772 in 2003. The number of fluoroquinolone-resistant NG (FRNG) isolates rose from 3 in 2000 to 56 in 2003 (p < 0.001). FRNG isolates amongst men who have sex with men increased from 1 in 568 isolates (0.2%) in 2000 to 50 in 478 isolates (10.5%) in 2003 (p < 0.001). Amongst heterosexual men, FRNG rose from 2 per 275 (0.7%) in 2000 to 16 per 297 (5.4%) in 2002 and dropped to 6 per 190 (3.4%) in 2003 (p = 0.146). No FRNG isolates were found in women in 2003 (2000: 0/180 (0.0%); 2001: 2/160 (1.3%); 2002: 4/183 (2.2%). CONCLUSION: The recent incidence of FRNG among men who have sex with men to over 5% makes ciprofloxacin and other fluoroquinolones obsolete as the first-choice treatment option for uncomplicated gonorrhoea if no antibiogram is available. It is advised to use cefotaxim when an antibiogram is not available (yet).

[Shigellosis, a sexually transmitted disease in homosexual men]. / Shigellose, een seksueel overdraagbare aandoening bij homoseksuele mannen.

A study of the registered number of Shigella infections in Amsterdam for the period 1997-2001 revealed that in 2001, there was an increase in the number of homosexual patients with oral-anal contacts as source for their infections. All of these infections were caused by subtype Shigella sonnei. The infections were not associated with a specific meeting place for homosexual men. A relationship with an underlying HIV-infection is likely.

[Typhoid fever in Amsterdam, 1991-2000, and the simplification of the national protocol for source and contact tracing]. / Buiktyfus in Amsterdam, 1991-2000, en vereenvoudiging van het landelijk protocol voor bron- en contactopsporing.

OBJECTIVE: To determine the incidence of patients reported with typhoid fever in Amsterdam (1991-2000) and to evaluate the contact tracing for those patients with the specific objective of examining whether contact tracing can be simplified. DESIGN: Retrospective. METHOD: From an automated database, data were collected on all reported typhoid fever patients in Amsterdam during the period 1991-2000 and on their contact persons. RESULTS: One hundred and one patients with typhoid fever were reported during the study period, and Salmonella typhi infection was diagnosed in 12 of the 281 household contacts. For 96 of the 101 index patients, travelling abroad was the most likely source of infection. In 8 of the 12 contact persons with an S. typhi infection, the index person was the most likely source of infection, which is equivalent to a secondary transmission rate of 2.8% (8/277). Seven of the 8 secondary infected persons had symptoms indicative of typhoid fever infection and S. typhi was found in all their first stool samples. CONCLUSION: Supported by these results, the national guidelines for source and contact tracing in the case of typhoid fever have been amended. In the case of index patients with bad toilet hygiene or who are responsible for food preparation, the faeces of all household contacts must be examined once. If the contact persons have symptoms indicative of an S. typhi infection and/or if their work involves food preparation, their faeces should also be tested once. The changes to the national protocol will markedly reduce the labour-intensity of tracing and testing the contacts of patients with typhoid fever, thereby maintaining the quality of the process. Tracing the source of infection in the case of patients with typhoid fever will also remain important in the future in order to detect potential transmission within the Netherlands at an early stage.

[Increased Neisseria gonorrhoeae quinolone resistance in Amsterdam]. / Toename van chinolonresistentie bij Neisseria gonorrhoeae in Amsterdam.

In addition to a rise in the number of cases of gonorrhoea, the susceptibility of Neisseria gonorrhoeae to antibiotics is also a cause for concern. After a period of high resistance rates to penicillin and tetracycline between 1985 and 1995, resistance rates have dropped considerably in recent years, probably due to changes in treatment regimens. However, recently we have seen an increasing number of quinolone-resistant N. gonorrhoeae isolates in Amsterdam, the Netherlands, a development that has previously been reported in other parts of the world. Some form of national resistance monitoring for gonococci is therefore urgently required to allow timely detection of changes in N. gonorrhoeae resistance.

Pneumococcal carriage in children in The Netherlands: a molecular epidemiological study.

In 1999, Engelen and coworkers investigated colonization in Amsterdam among 259 children attending 16 day-care centers (DCCs) and among 276 children who did not attend day-care centers (NDCCs). A 1.6- to 3.4-fold increased risk for nasopharyngeal colonization was observed in children attending DCCs compared with NDCC children, while no difference in antibiotic resistance was found between groups. The serotype and genotype distributions of 305 nasopharyngeal Streptococcus pneumoniae isolates of the latter study were investigated. The predominant serotypes in both the DCC and the NDCC groups included 19F (19 and 18%, respectively), 6B (14 and 16%, respectively), 6A (13 and 7%, respectively), 23F (9 and 7%, respectively), and 9V (7 and 7%, respectively). The theoretical vaccine coverage of the 7-valent conjugate vaccine was 59% for the DCC children and 56% for the NDCC group. Genetic analysis of the pneumococcal isolates revealed 75% clustering among pneumococci isolated from DCC attendees versus 50% among the NDCC children. The average pneumococcal cluster size in the DCC group was 3.8 and 4.6 isolates for two respective sample dates (range, 2 to 13 isolates per cluster), while the average cluster size for the NDCC group was 3.0 (range, 2 to 6 isolates per cluster). Similar to observations made in other countries, these results indicate a higher risk for horizontal spread of pneumococci in Dutch DCCs than in the general population. This study emphasizes the importance of molecular epidemiological monitoring before, during, and after implementation of pneumococcal conjugate vaccination in national vaccination programs for children.

Diagnosing genital ulcer disease in a clinic for sexually transmitted diseases in Amsterdam, The Netherlands.

The most common etiologic agents of genital ulcer disease (GUD) are herpes simplex virus type 1 (HSV-1), HSV-2, Treponema pallidum, and Haemophilus ducreyi. In an outpatient clinic for sexually transmitted diseases in Amsterdam, The Netherlands, specimens from 372 patients with GUD were collected from February to November 1996. Sera were collected at the time of the symptoms and, for most patients, also during follow-up visits. Swabs in viral transport medium were used for HSV culture and for detection of DNA. The most prevalent pathogen found was HSV-2, which was detected by culture in 35% of the patients and by PCR in 48% of the patients. Also, HSV-1 infection was more often detected by PCR (7.8%) than by culture (5.6%). Evidence for an active infection with T. pallidum was found in 1.9% of the patients, using serological tests. A multiplex PCR for simultaneous T. pallidum and H. ducreyi DNA detection was positive for T. pallidum in 3.3% of the samples and for H. ducreyi in only 0.9% (3 out of 368) of the samples. The sensitivity of the PCR was superior to that of culture for HSV detection and to that of serology for T. pallidum detection. Specific H. ducreyi immunoglobulin G antibodies were detected in sera of 5.2% of the patients, with no concordance between serology and PCR. In 37% of the cases, none of the tested microorganisms was detected. Performance of PCR in addition to conventional techniques significantly improved the diagnosis of GUD.

[Shigellosis in Amsterdam, 1991-1998: incidence and results of contact tracing]. / Shigellose in Amsterdam, 1991-1998: vóórkomen en resultaten van contactonderzoek.

OBJECTIVE: To determine the incidence of reported shigellosis in Amsterdam (1991-1998) and the factors related to the secondary attack rate of shigellosis. DESIGN: Retrospective. METHODS: From an automated data bank data were collected on all registered shigellosis patients in Amsterdam in the period 1991-1998, and their contacts found by contact tracing. RESULTS: 567 Patients with shigellosis had been reported and a Shigella infection has been diagnosed in 96 of the 983 contacts. The annual incidence decreased statistically significantly from 13 to 8/100.000. 329 males and 334 females were infected. The highest number of cases was found in children from 0-4 years and among adults from 20-34 years. Of the 663 patients 106 (16%) required hospitalization; for children under 7 this proportion was 30% (32/108). Among the contacts (excluding the 14 contacts with the same foreign source and the same first sickness day as the index patient) the secondary attack rate was 8%. Young age, of both the patient and the contact was independently related to a higher secondary attack rate. CONCLUSION: With contact tracing for shigellosis a large number of secondary infections were found. Given the high infection rate and large number of hospitalisations among children, contact tracing should focus at this young age group.

[Tinea capitis in primary school age children in southeastern Amsterdam: primarily due to Trichophyton tonsurans]. / Tinea capitis bij kinderen op de basisschoolleeftijd in Amsterdam Zuid-Oost: vooral Trichophyton tonsurans.

OBJECTIVE: To establish prevalence and aetiology of tinea capitis in children attending primary school in Amsterdam South-East. DESIGN: Prevalence survey. METHODS: The Municipal Health Service Amsterdam, the Netherlands, selected classes of four primary schools in a survey with children clinically suspected of having tinea capitis as well as classes without clinical cases. Per school at least one class with a notified case was included. Written information was provided to all parents; the parents of three children refused participation. After clinical examination by a team of physicians and nursing staff scalp cultures were taken using the brush method from 315 children (aged 4-12 years) in 16 classes. RESULTS: The clinical diagnosis 'tinea capitis' was established in 25 children, significantly more in boys than in girls (relative risk (RR) = 2.92: 95% confidence interval (95% CI) 1.20-7.11). Of all children 7% had positive cultures, more boys than girls (RR = 3.13: 95% CI: 1.18-8.28). Symptomatic cases (confirmed by culture) amounted to 3.2% of all children. The carrier rate was 3.8%. Trichophyton tonsurans was the most frequently isolated dermatophyte both in symptomatic children and in carriers. CONCLUSION: In 7% of all children (3.2% with symptoms of tinea capitis, 3.8% without) dermatophytes were cultured from scalp samples, the main aetiologic agent being T. tonsurans.

[Direct antibiotic sensitivity testing in the treatment of urinary tract infections in a nursing home]. / Directe gevoeligheidsbepaling voor antibiotica bij de behandeling van urineweginfecties in een verpleeghuis.

Urinary tract infections occur frequently in nursing homes. Treatment is usually empiric without microbiological investigation. Because there is widespread resistance to the most frequently used antibiotics, we tested a relatively simple method (direct sensitivity testing for 7 antibiotics) to get information about the antibiotic resistance. The results, with 49 urine samples in the evaluation, showed a concordance of our direct sensitivity test with conventional culture (the golden standard) of 89.8% (35/342 evaluations were not in concordance). The concordance for the result 'sensitive' was 98.8% (3/240 results showed 'false-sensitive'), and the the result 'resistant' 68.6% (32/342 results showed 'false-resistant'). Urinary tract infections in the nursing home can be treated more quickly and more adequately with antibiotics with the information obtained by direct sensitivity testing. This method can be recommended as an alternative to empiric treatment.

Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by ligase chain reaction-based assays with clinical specimens from various sites: implications for diagnostic testing and screening.

Ligase chain reaction (LCR)-based tests for the diagnosis of Chlamydia trachomatis and Neisseria gonorrhoeae infections in men and women attending a sexually transmitted disease clinic were evaluated. LCR testing of urethral swab and urine specimens from men and cervical swab and urine specimens from women was compared with culture of male urethral swabs and female cervical and urethral swabs, respectively. An expanded "gold standard" was defined as a positive culture or at least one specimen confirmed to be positive by LCR testing. The prevalence of C. trachomatis infection as detected by cell culture was 7.0% among 614 men and 5.0% among 602 women. By LCR, these values increased to 11.4 and 9.9% with urethral swabs and urine, respectively, for men and 9.6 and 9.1% with cervical swabs and urine, respectively, for women. Relative to the expanded gold standard, the sensitivity of cell culture with male urethral swabs or female cervical swabs was 57.3 and 45.5%, respectively, compared with corresponding values of 93.3 and 87.9% for LCR. The sensitivity of LCR with urine specimens was 77.3 and 78.8% for men and women, respectively. The prevalence of N. gonorrhoeae infection as detected by culture was 5.9% among 220 men and 2.9% among 383 women. The corresponding values were 8.2 and 5.5%, respectively, by LCR testing of swabs. Prevalence values by LCR testing of urine were 7.3% for men and 2.9% for women. The sensitivity of culture was 72.2% for men and 50.0% for women. The sensitivities of LCR were 100% with male urethral swabs, 95.4% with female cervical swabs, 88.9% with male urine, and 50.0% with female urine. These results indicate that the LCR-based assays represent a major improvement in C. trachomatis and N. gonorrhoeae diagnostics. The sensitivity of testing of urethral or cervical swabs by LCR was markedly greater than that by culture. The sensitivity of testing female or male urine specimens was equal to or greater than that of culturing cervical or urethral specimens. LCR testing of urine specimens may prove useful for screening for C. trachomatis.

[An outbreak of methicillin-resistant Staph aureus in a nursing home]. / Een uitbraak van meticilline-resistente Staphylococcus aureus in een verpleeghuis.

The introduction of methicillin-resistant Staphylococcus aureus (MRSA) in an Amsterdam nursing home (312 beds) by a patient discharged from a local hospital, the spread of this strain to other residents and staff of the nursing home and the actions taken to prevent this spread are described. During the period when this MRSA strain was circulating residents and staff members were checked periodically for presence of MRSA. In spite of all preventive measures as implemented in Dutch hospitals (including isolation of infected residents) additional residents (in a total of 8) and staff members acquired the MRSA strain. Relaxation of the precautions (no more isolation) and continued instruction of the members of the staff was attended by a decrease of further contamination. Four of 8 residents died while being colonised or infected. The course of this epidemic illustrates that limited precautions and proper training of staff in hygiene can restrict spread of MRSA in nursing homes.

A comparison of yield from cervix versus vagina for culturing Candida albicans and Trichomonas vaginalis.

OBJECTIVE: To determine the agreement of culture results of Candida albicans and Trichomonas vaginalis from the cervix versus posterior fornix in women with vaginal symptoms. DESIGN: Same patient comparison of culture results from two sample sites. SETTING: Twenty one general practices in Amsterdam and the east of the Netherlands. SUBJECTS: Six hundred and eighty two women aged 15 to 55 years with vaginal symptoms, seen between 1 October 1987 and 31 May 1990. MAIN OUTCOME MEASURES: For each site (cervix and posterior fornix) the proportion of detected C albicans and T vaginalis. The sensitivity of the cervical swab related to the vaginal one. The percentage of concordance for both microorganisms. RESULTS: In 248 (34%) women C albicans was diagnosed and in 38 (6%) T vaginalis. In 99% of the proven C albicans cases, the yeast was found in the vagina. In 94% C albicans was isolated from the cervix. Sensitivity of the cervical swab was 94%. In 98% of the patients a concordant observation was made regarding detection of yeast. In 97% of the proven T vaginalis cases the protozoon was found in the vagina. In 91% T vaginalis was detected from the cervical swab. Sensitivity of the cervical swab was 92%. The culture results were concordant in 99%. CONCLUSION: The yield from the vaginal source was slightly better than that from the cervix for culture of both microorganisms. For screening purposes, specimen-collection for culture of N gonorrhoeae, C albicans and T vaginalis can be combined in one swab taken from the cervix.

[Benefit of the serological screening program for syphilis in pregnant women in Amsterdam in the period 1985-1989]. / Het nuttig effect van het serologische screeningsprogramma voor lues bij zwangere vrouwen in Amsterdam in de periode 1985-1989.

The results of the serological syphilis screening programme for pregnant women in the region of Amsterdam in the period 1985-1989 are described. In addition, a cost-benefit analysis was done to determine useful effects of the programme. Every GP and obstetrician routinely takes blood samples from pregnant women to determine the blood group, rhesus factor and syphilis serology. In the period 1985-1989, a total of 37,520 serum samples were screened for syphilis in the Amsterdam region by the Central Laboratory of the Blood Transfusion Service (until mid-1986) and by the Regional Public Health Laboratory of the Municipal Health Service (from mid-1986). In 55 women (0.15%) both the Treponema pallidum haemagglutination assay (TPHA) and the venereal disease research laboratory (VDRL) tests were positive. Further evaluation of these 55 women ultimately brought to light 10 women with positive syphilis serology who had not been treated and consequently might infect their child with Treponema pallidum. Considering the various transmission percentages of the bacterium from mother to foetus, which depend on the stage of the maternal infection, the screening programme has prevented two cases of congenital syphilis. This brings the cost-benefit ratio of the syphilis screening programme for the region of Amsterdam to 1:6.2. In view of these findings there is no reason to reconsider the current screening practice in Amsterdam.

Epidemiology of the Bacteroides fragilis group in the colonic flora in 10 patients with colonic cancer.

We report the relative frequencies of members of the Bacteroides fragilis group in the faeces, in colon lavage fluid obtained pre-operatively, and in colonic tissue specimens obtained at operation from 10 patients with colonic cancer. B. vulgatus was the most and B. fragilis and B. ovatus were the least frequently isolated Bacteroides spp. in the faeces of the 10 subjects. B. uniformis and B. thetaiotaomicron ranked second and third in the faeces. The relative frequencies of all species except B. fragilis were lower in the lavage fluid and in cultures of mucosa. The relative frequency of B. fragilis increased from 4% in faeces to 39% in the final lavage fluid and to 42% in the colonic mucosa culture. Our results suggest that B. fragilis has a more intimate association with the gut mucosa than other members of the B. fragilis group, which might be one explanation for the high incidence of this species in gut-associated intra-abdominal infections.

Serous otitis media (S.O.M.). A bacteriological study of the ear canal and the middle ear.

A bacteriological study of the middle-ear effusions and the ear canals in children with chronic serous otitis media (S.O.M.) was performed. Sixty-eight children (127 ears) were investigated. From this study it appeared that cleansing of the ear canal with 0.5% chlorhexidine in 70% ethanol for 30 s is partially effective; micro-organisms (diptheroids, Staphylococcus epidermidis) could still be isolated in 29%. Cleansing of the ear canal decreases the incidence of middle-ear fluid contamination by non-pathogenic ear canal organisms (diptheroids, Staphylococcus epidermidis, Aerococcus), but after cleansing, 'non-pathogenic' micro-organisms could still be isolated in 33% of the effusions (diptheroids, Staphylococcus epidermidis). From 12% of the middle-ear effusions pathogenic micro-organisms (Hemophilus influenzae, Staphylococcus pneumoniae) were isolated; cleansing of the ear canal did not influence this percentage. Anaerobics were not isolated from the middle-ear effusions.