Clinical/serological outcome in humans bitten by Babesia species positive Ixodes ricinus ticks in Sweden and on the Åland Islands.

The risk of contracting babesiosis after a tick bite in Sweden and on the Åland Islands, Finland, is unknown. We investigated clinical and serological outcomes in people bitten by Ixodes ricinus ticks positive for Babesia species. Ticks, blood and questionnaires were obtained from study participants in Sweden and on the Åland Islands. Sixty-five of 2098 (3.1 %) ticks were positive by real-time PCR. Three Babesia species were detected, Babesia microti (n = 33), B. venatorum (n = 27) and B. capreoli (n = 5), the latter species not known to cause human infection. Half (46 %) of the Babesia PCR-positive ticks also contained Borrelia spp. Fifty-three participants bitten by a Babesia PCR-positive tick and a control group bitten by a Babesia PCR-negative tick were tested for B. microti IgG antibodies by IFA. The overall seroprevalence was 4.4 %, but there was no significant difference between the groups. None of the participants seroconverted and no participant with a Babesia PCR-positive tick sought medical care or reported symptoms suggestive of babesiosis. Given the prevalence of Babesia in I. ricinus ticks in southern Sweden and on the Åland Islands, babesiosis should be considered a possible diagnosis in symptomatic residents who seek medical care following tick exposure.

Direct genetic characterization of Toxoplasma gondii from clinical samples from Denmark: not only genotypes II and III.

Genetic variation within Toxoplasma gondii can have both clinical and epidemiological significance, while the genotypes circulating in many parts of the world, including the Nordic country Denmark, are still unknown. We genetically characterized T. gondii strains that had been detected in human clinical samples in Denmark in 2011-2016. Samples that had tested positive for T. gondii DNA and had a quantification cycle value <33 were included in this study and subjected to direct genetic characterization of T. gondii based on length-polymorphism of 15 microsatellite markers. A total of 23 DNA samples from 22 individual patients were analyzed. The results were consistent with genotype II with 15/15 markers amplified from seven samples from the central nervous system (CNS) including two samples from one patient, four ocular samples, and one unspecified sample; with genotype III with 15/15 markers amplified from two ocular samples; with genotype Africa 1 with 15/15 markers amplified from one amniotic fluid sample and from one CNS-sample; with atypical genotype with 15/15 markers amplified from one CNS-sample and with 11/15 markers amplified from one CNS-sample; and with HG12-like genotype with 9/15 markers amplified from one CNS-sample. Genotype II, which is endemic in Europe, was predominant, but more than a third of the successfully genotyped strains were non-type-II. The possibility that clinical toxoplasmosis is caused by a strain that is not considered endemic to the region is definitely not negligible.

History of antimicrobial use and the risk of Dientamoeba fragilis infection.

Associations between antimicrobial use and risk of enteric infection with intestinal protozoa are scarcely studied. The aim of this study was to quantify the risk of Dientamoeba fragilis infection conferred by exposure to antimicrobials. We conducted a registry-based retrospective cohort study of 9,945 Danish patients investigated for D. fragilis infection between 2008 and 2011, using data from the Danish Register of Medicinal Product Statistics, and calculating relative risks (RR) for D. fragilis infection by stratified binary regression. Furthermore, we conducted a population based case-control study using controls sampled from the Danish Civil Registration System, calculating hazard ratios (HR) for D. fragilis infection by conditional logistic regression. Exposure to metronidazole was found to confer decreased risk of D. fragilis infection; however, similar associations were found for antimicrobials not commonly used to treat D. fragilis, such as broad-spectrum penicillin, fluoroquinolones, and macrolides. In contrast, mebendazole exposure was associated with increased risk. The intake of antimicrobials influences the risk of D. fragilis.

The incidence and clinical symptomatology of Clostridium difficile infections in a community setting in a cohort of Danish patients attending general practice.

Clostridium difficile infection (CDI) is gradually being recognised as a cause of morbidity in the community. We investigated the incidence and clinical characteristics of CDI in a community setting and characterised the C. difficile strains by toxin gene profiling and polymerase chain reaction (PCR) ribotyping. Patients included in the study had attended general practice, primarily because of diarrhoea; CDI patients (259 patients; 121 <2 years of age) had positive cultures for toxigenic C. difficile and non-CDI patients (455 patients) were culture-negative. Outcome variables included the frequency and duration of diarrhoea, vomiting, stomach ache, fever >38 °C, weight loss and sick leave. Data were analysed by logistic regression. CDI patients <2 and ≥2 years of age with C. difficile as the only enteropathogen in the faecal sample reported slimy stools (65% vs. 62%), stomach ache (60% vs. 75%), weight loss (50% vs. 76%) and duration of diarrhoea >15 days (59% vs. 73%) as the predominant symptoms. CDI patients ≥2 years old reported duration of diarrhoea >15 days more often compared to non-CDI patients (73% vs. 27 %, p < 0.0001). The annual incidence of CDI was 518 and 23/100,000 for patients <2 and ≥2 years of age, respectively, and 46/100,000 in the subgroup of patients ≥60 years of age. CDI was characterised by stomach ache and persistent diarrhoea, often leading to weight loss. This emphasises the importance of diagnosing CDI not only in hospitalised patients, but also in individuals ≥2 years of age attending general practice because of gastrointestinal symptoms, especially in the elderly, where the incidence of CDI is high.

Risk factors for Clostridium difficile infection in the community: a case-control study in patients in general practice, Denmark, 2009-2011.

To identify risk factors for Clostridium difficile infection (CDI) in Danish patients consulting general practice with gastrointestinal symptoms, a prospective matched case-control study was performed; cases (N = 259) had positive cultures for toxigenic C. difficile and controls (N = 455) negative cultures. Data were analysed by conditional logistic regression. In patients aged ⩾2 years (138 cases), hospitalization [odds ratio (OR) 8·4, 95% confidence interval (CI) 3·1-23], consumption of beef (OR 5·5, 95% CI 2·0-15), phenoxymethylpenicillin (OR 15, 95% CI 2·7-82), dicloxacillin (OR 27, 95% CI 3·6-211), and extended spectrum penicillins (OR 9·2, 95% CI 1·9-45) were associated with CDI. In patients aged <2 years none of these were associated with CDI, but in a subgroup analysis contact with animals was associated with CDI (OR 8·1, 95% CI 1·0-64). This study emphasizes narrow-spectrum penicillins, and suggests beef consumption, as risk factors for CDI in adults, and indicates a different epidemiology of CDI in infants.

Dientamoeba fragilis in Denmark: epidemiological experience derived from four years of routine real-time PCR.

The intestinal protozoon Dientamoeba fragilis remains a clinical entity of dubious significance. While several previous studies address questions of epidemiology, only a handful have systematically employed and reported on the results from real-time polymerase chain reaction (qPCR), the best currently available diagnostic modality, and the comparison of results from different studies is, therefore, difficult. Since 2007, Statens Serum Institut (Denmark) has utilised qPCR for D. fragilis as routine diagnostic work-up for intestinal parasitosis, testing more than 22,000 samples from 2008 through 2011, and the aim of this study was to report on the results and experiences gained in the process. We demonstrate a staggeringly high proportion (43%) of investigated patients positive for D. fragilis, ranging from 12 to 71% depending on age group, showing a bimodal age distribution peaking in children and adults of parental age, as well as a clear association between exposure to children and risk of D. fragilis infection. We discuss these findings in light of the pinworm egg vector hypothesis and substantiate further our knowledge of risk factors pertaining to D. fragilis carriage.

Detection of candidaemia in patients with and without underlying haematological disease.

Diagnosing candidaemia remains difficult despite the development of new diagnostics. We report a direct comparison of three different blood-culture systems and four indirect tests. One hundred and fourteen episodes either with haematological disease and fever despite antibacterials, or with documented invasive candidiasis, were enrolled prospectively. Clinical, para-clinical information and surveillance cultures were obtained. Blood culture was performed using conventional blood-culture bottles, mycosis bottles, and the Isolator 10 lysis centrifugation system. Serum D-arabinitol/L-arabinitol (DA/LA) ratios were determined by gas chromatography mass spectrometry. Antigen, mannan-antigen (Ag) and anti-mannan antibody (Ab) were detected by CandTec, Platelia Candida Ag ELISA and Candida AB/AC/AK kits, respectively. Episodes were classified as proven (n = 24), probable (n = 14), possible (n = 52) or unlikely (n = 24) invasive candidiasis. Candidaemia involved C. albicans (17), C. albicans + C. glabrata (3), C. tropicalis (1) and yeast (1). Mycosis bottles yielded two additional positives and the conventional blood culture yielded one positive not identified by other blood-culture methods. Considering proven and unlikely episodes, respectively, sensitivity and specificity were as follows: mannan-Ag and/or anti-mannan Ab: 83.3%, 78.3%; DA/LA ratio: 41.7%, 86.4%; and CandTec Candida Ag: 66.6%, 70.8%. Lowering the cut-off values to mannan-Ag 0.10 ng/mL and anti-mannan Ab 4 AU/mL, the values were: 100%, 73.9%. Applying the DA/LA ratio to only patients with haematological neutropenia the values were: 75%, 90.5%. Fungal blood culture allowed slightly improved detection of candidaemia. The best indirect test performance was obtained from combined mannan-Ag and anti-mannan Ab detection, especially with lower cut-offs. DA/LA ratio appears to be useful in the context of haematological neutropenia.

Blastocystis: unravelling potential risk factors and clinical significance of a common but neglected parasite.

Two independent studies were conducted to describe symptoms and potential risk factors associated with Blastocystis infection. Isolates were subtyped by molecular analysis. In the NORMAT study (126 individuals randomly sampled from the general population) 24 (19%) were positive for Blastocystis. Blastocystis was associated with irritable bowel syndrome (P=0.04), contact with pigs (P<0.01) and poultry (P=0.03). In the Follow-up (FU) study (follow-up of 92 Blastocystis-positive patients), reports on bloating were associated with subtype (ST) 2 (P<0.01), and blood in stool to mixed subtype infection (P=0.06). ST1 was more common in FU individuals (32%) than in NORMAT individuals (8%), whereas single subtype infections due to ST3 or ST4 were seen in 63% of the NORMAT cases and 28% of the FU cases. Only FU individuals hosted ST7, and ST6/7 infections due to ST7 or ST9 were characterized by multiple intestinal symptoms. The data indicate subtype-dependent differences in the clinical significance of Blastocystis.

A foodborne outbreak of Cryptosporidium hominis infection.

Foodborne outbreaks of cryptosporidiosis are uncommon. In Denmark human cases are generally infrequently diagnosed. In 2005 an outbreak of diarrhoea affected company employees near Copenhagen. In all 99 employees were reported ill; 13 were positive for Cryptosporidium hominis infection. Two analytical epidemiological studies were performed; an initial case-control study followed by a cohort study using an electronic questionnaire. Disease was associated with eating from the canteen salad bar on one, possibly two, specific weekdays [relative risk 4.1, 95% confidence interval (CI) 2.1-8.3]. Three separate salad bar ingredients were found to be likely sources: peeled whole carrots served in a bowl of water, grated carrots, and red peppers (in multivariate analysis, whole carrots: OR 2.1, 95% CI 1.1-4.0; grated carrots: OR 2.1, 95% CI 1.2-3.9; peppers: OR 3.3, 95% CI 1.7-6.6). We speculate that a person excreting the parasite may have contaminated the salad buffet.

The prevalence of Dientamoeba fragilis in patients with suspected enteroparasitic disease in a metropolitan area in Denmark.

The prevalence of Dientamoeba fragilis in patients from a metropolitan area in Denmark was determined by examination of paired stool samples using two techniques: a formol ethyl-acetate concentration technique with unpreserved faeces and a permanent staining technique on faeces preserved with sodium acetate-acetic acid-formalin (SAF). Using the SAF permanent staining technique and the formol ethyl-acetate concentration technique, 25% and 15% of the specimens, respectively, were parasite-positive. D. fragilis was detected in 12 of the 103 patients, only two of whom harboured other recognised pathogenic parasites. Overall, D. fragilis had a remarkably high prevalence in the metropolitan area of Denmark investigated.

Blastocystis: subtyping isolates using pyrosequencing technology.

Blastocystis is a prevalent single-celled enteric parasite of unresolved clinical significance. Efforts based on molecular methodologies to establish whether pathogenicity is linked to specific isolates of the genetically diverse genus of Blastocystis have been scarce and so far yielded ambiguous results which can be difficult to interpret. To alleviate some of the problems related to unravelling the molecular epidemiology of Blastocystis infections we developed and evaluated a simple and high-throughput sequence analysis (SQA) pyrosequencing technique based on the detection of genotype-specific nucleotide polymorphisms in the 18S small subunit rRNA gene for a rapid and cost-effective post-PCR screening of Blastocystis genotypes. The method was effectively capable of genotyping 48/48 isolates positive by nested PCR in approximately one hour, and in 94% of the cases the isolate detected by PCR and pyrosequencing was also detected by one of two different PCR assays with subsequent dideoxy sequencing.

Usefulness of Toxoplasma gondii recombinant antigens (GRA1, GRA7 and SAG1) in an immunoglobulin G avidity test for the serodiagnosis of toxoplasmosis.

The precise diagnosis of an acute and recent Toxoplasma infection in pregnant women and the newborn child is important before treatment. This study describes a new Toxoplasma gondii IgG avidity test based on a combination of recombinant GRA1, GRA7 and SAG1 antigens and shows that this test is useful for diagnostic purposes and may replace the lysed, whole-cell antigens. Although more sera need to be tested, the results obtained here suggest that the IgG avidity test performed with rec-antigens correlated more with the stage of a T. gondii infection than the IgG avidity results obtained with the lysed, whole-cell antigen test, the VIDAS Toxo IgG avidity (bioMérieux).

Usefulness of Toxoplasma gondii-specific recombinant antigens in serodiagnosis of human toxoplasmosis.

Toxoplasma gondii SAG1, GRA1, and GRA7 recombinant antigens may be regarded as tools for the detection of T. gondii immunoglobulin G antibodies in persons with chronic and acute toxoplasmosis. GRA7 is more correlated with acute toxoplasmosis. A combination of these antigens will increase the sensitivity of enzyme-linked immunosorbent assays.

Transurethral interstitial laser coagulation of the prostate and transurethral microwave thermotherapy vs transurethral resection or incision of the prostate: results of a randomized, controlled study in patients with symptomatic benign prostatic hyperplasia.

OBJECTIVE: To compare the efficacy and frequency of complications of transurethral interstitial laser coagulation (ILC) and transurethral microwave thermotherapy (TUMT) with transurethral resection or incision of the prostate (TURP/TUIP) in patients with symptomatic benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: Forty-eight patients were randomized to undergo ILC, 46 to TUMT and 24 to TURP/TUIP; they were followed for 6 months and the outcome analysed on an intention-to-treat basis. RESULTS: At 6 months the symptom scores and maximum urinary flow rate (Qmax) had improved significantly in all groups. At 6 months the mean symptom score was 9.2 in both experimental groups and 6.8 in the control group (P > 0.05); the mean Qmax was 20.6 mL/s in the control group, 16.2 in the ILC group (P > 0.05 vs control) and 13.2 in the TUMT group (P < 0.05 vs. the control group). In the TUMT group patients developing urinary retention afterward had a significantly greater increase in Qmax than those who did not. The types of complications in the three groups varied. Urinary tract infection occurred frequently in the experimental groups, especially after ILC, whereas the 'well-known' complications of TURP occurred in the control group. Overall, 36% in the ILC, 54% in the TUMT and 73% in the control group had no complications (retrograde ejaculation excluded) during the first 6 months. One patient in the TUMT group underwent TURP after 3 months, whereas no patients in the ILC or the con-trol group were re-treated for BPH within the first 6 months. CONCLUSION: In the short term both ILC and TUMT are reasonable alternatives to standard transurethral surgery for symptomatic BPH, where the reduction of symptoms is the primary goal of treatment. However, both ILC and TUMT were associated with morbidity, although the complication profiles differed from those after TURP/TUIP. Both ILC and TUMT seem advantageous in some patients because of the reduced risk of bleeding and the eliminated risk of TUR syndrome, and because TUMT only requires local anaesthesia. Thus, as neither treatment is better in all aspects, the advantages of one technique over the other must be weighed when deciding how to treat each patient.

Cost-effectiveness of new treatments for benign prostatic hyperplasia: results of a randomized trial comparing the short-term cost-effectiveness of transurethral interstitial laser coagulation of the prostate, transurethral microwave thermotherapy and standard transurethral resection or incision of the prostate.

OBJECTIVES: To compare the short-term cost-effectiveness of ILC and TUMT with that of transurethral resection or incision of the prostate in patients with symptomatic benign prostatic hyperplasia. MATERIAL AND METHODS: One hundred and eighteen patients were randomized to ILC, TUMT and TUR-P/TUI-P in 2:2:1 fashion. The use of resources within the first 6 months of follow-up were measured and the cost of treatment for each patient were calculated. A few parameters, primarily related to the time spent by the staff, were measured only in a subgroup of patients. A cost-effectiveness analysis was performed based on the average calculated cost and change in I-PSS found in each group. For costly resources a sensitivity analysis was performed. RESULTS: At 6 months the cost was lowest in the TUMT group and highest in the ILC group. The cost-effectiveness ratio (C/E) was 763 DKK/point reduction in I-PSS in the control group and 1.200 and 938 in the ILC and TUMT group, respectively. An incremental analysis demonstrated that TUR-P/TUI-P dominated ILC. In a similar comparison of the TUMT and the TUR-P/TUI-P group an incremental ratio of 170 DKK/extra point of reduction in I-PSS was found in the TUR-P/TUI-P group. CONCLUSION: In the short-term TUMT and TUR-P has comparable cost-effectiveness. TUR-P was slightly more effective than TUMT, but the cost was also slightly higher. In our set-up of ILC the short-term cost-effectiveness of ILC was inferior to that of TUR-P. Conclusions should be made with caution, since the follow-up at present is short.

Characterisation of the allelic variation in the rpoS gene in thirteen K12 and six other non-pathogenic Escherichia coli strains.

The nucleotide sequence of rpoS, the gene for the stress sigma factor, was determined in 13 different K12 strains of Escherichia coli. The results indicate that the original K12 isolate carried an amber mutation at codon 33, which in 50% of the derivatives is mutated by a single base substitution to a coding triplet, in most cases to CAG encoding glutamine. The six non-K12 strains examined here had GAG, encoding glutamate, in position 33. The two most divergent strains had three and seven neutral substitutions in rpoS and carried insertions of 2100 and 2900 bp, respectively, just downstream of the gene. The genetic variations in rpoS were compared with the variation in RpoS-related phenotypes, by measuring catalase (KatE) activity, glycogen accumulation and acid phosphatase levels, and a katEp-gfp fusion was used to visualise katE gene transcription. The RpoS phenotypes of the six rpoS(33E) strains varied significantly more than that of the K12 rpoS(33Q) strains, especially with respect to acid phosphatase levels. This was due to the absence of the gene for the transcriptional activator AppY from four of the rpoS(33E) strains, while all the K12 derivatives carried this gene. When cloned into a LacI-controlled vector and compared in a rpoS::Tn 10 background, the RpoS(33Q) and RpoS(33E) variants showed the same activity.