Epidemiology and laboratory characteristics of Trichomonas vaginalis infection in Croatian men with and without urethritis syndrome: a case-control study.

OBJECTIVES: The main objective of this study is to determine the prevalence of trichomoniasis in men with and without symptoms of urethritis, with concomitant analysis of sociodemographic and behavioural specificities of both groups. Also, the objective is to evaluate laboratory methods used in the diagnostics of this parasitic disease. METHODS: A total of 500 men with and 200 without urethritis symptoms were included in the study. Every respondent filled out a questionnaire asking for some general data, specific information about habits, sexual behaviour and symptoms. Sediment of first void urine was analysed by wet mount microscopy, cultivation in Diamond's medium and real-time PCR. RESULTS: In the symptomatic group, Trichomonas vaginalis infection was documented in 2.4% of respondents by wet mount microscopy, in 4.8% by cultivation and in 8.2% by real-time PCR. In the asymptomatic group, infection was proven using the same methods in 1.0%, 1.5% and 2.0% of the respondents, respectively. Trichomoniasis prevalence was statistically significantly higher in the respondents manifesting urethritis symptoms when cultivation (χ2=4.20, p=0.041) and real-time PCR (χ2=9.20, p=0.002) were used. Several epidemiological risk factors were identified, and greater sensitivity of real-time PCR was found in comparison with microscopy and culture. CONCLUSIONS: Trichomonas infection was statistically more frequent in men with urethritis syndrome. Assuming that the samples found positive by any laboratory technique are truly positive, it can be concluded that the real-time PCR showed the greatest sensitivity of all the methods used in this study.

Ureaplasma urealyticum and Ureaplasma parvum in women of reproductive age.

OBJECTIVES: To determine the incidence of Ureaplasma urealyticum and Ureaplasma parvum (UP) in symptomatic and asymptomatic women of reproductive age and to estimate antibiotic susceptibility of ureaplasma isolates. MATERIALS AND METHODS: This study included 424 ureaplasma positive women of 1,370 tested women who visited gynecological practices during 2010. Cervicovaginal or urethral swab specimens from each patient were obtained for cultivation and molecular typing by RT-PCR. RESULTS: Ureaplasma spp. was identified by cultivation in 424 (34.4 %) cases, of which 79.0 % were from women with symptoms and 21.0 % from women without symptoms. Among ureaplasma positive women, 121 (28.5 %) were pregnant. Genotyping was successful in 244 strains, and the majority of samples were identified as UP (92.6 %). Among genotyped isolates, there were 79.5 % from symptomatic and 20.5 % from asymptomatic women; 29.9 % from pregnant and 70.1 % from non-pregnant women. There was no difference in the incidence of ureaplasma type regarding symptoms. Antibiotic susceptibility of 424 ureaplasma isolates identified by cultivation showed that all strains were susceptible to doxycycline, josamycin, erythromycin, tetracycline, clarithromycin and pristinamycin, but there was lower susceptibility to quinolone antibiotics, i.e., 42.9 and 24.5 % isolates were susceptible to ofloxacin and ciprofloxacin, respectively. CONCLUSION: This study shows that UP was the most frequent isolated ureaplasma species (92.6 %). Regarding antibiotic susceptibility, quinolones are not the best choice for the treatment of ureaplasma infections, while macrolides and tetracyclines are still effective.

Lower urinary tract infections and the effects of hormone therapy in postmenopausal women in the Zagreb region.

Urinary tract infections (UTI) remain one of the most common bacterial infections seen in adult women of all ages. In postmenopausal women, the aging process contributes to local complaints in the lower urogenital tissue, including UTI. Our study was conducted at gynecological practices of the health centers in the Zagreb region, Croatia, during 2009. The study included postmenopausal women with urinary symptoms divided into two groups: hormone therapy (HT) users and controls. The objectives were to estimate microbiologically proven lower UTIs (LUTIs) in postmenopausal women with urinary symptoms and the effect of regular HT use on microbiologically confirmed LUTIs. Out of 2338 postmenopausal patients, there was a significantly higher rate of women with urinary symptoms in HT users, namely 64.4% (143/221), compared to the control group at 4.8% (102/2116). Of the 245 patients with urinary symptoms, in 58.8% (144/245) the infection was microbiologically confirmed. Hormone therapy users showed a statistically significant lower rate of microbiologically proven LUTIs (46.9%, 67/143) compared to controls (75.5%, 77/102, p < 0.001). Data analysis also showed the efficacy of local as well as systemic HT treatment compared with the control group (p < 0.00, p = 0.049). But there was a significant difference in the frequency of LUTIs between patients who used local (30.3%, 20/66) and systemic (61.1%, 47/77) HT (p < 0.001). The patients who, regulary used therapy, in the local HT group as well as in the group on systemic HT showed a lower incidence of LUTIs compared to controls (p < 0.00, p = 0.006). In patients who did not regulary use therapy, there were no significant differences between either local (63.6%, 7/11)) or systemic (76.9%, 20/26) HT non- regular users and the control group (75. 5%, 77/102) (p = 0.917, p = 0.625). The high percentage of patients with non-microbiologically confirmed LUTIs (41.2%, 101/245) suggested the significant role microbiological testing has in LUTI diagnosis. Both local and systemic HT use was related to LUTI reduction.

A study of the genetic variability of human respiratory syncytial virus in Croatia, 2006-2008.

Human respiratory syncytial virus (HRSV) is a common etiological agent of acute lower respiratory tract disease in infants. The molecular epidemiology of HRSV in Croatia over four consecutive seasons (from 2006 to 2008) was investigated. A total of 72 HRSV samples were chosen from 696 screened cases in a pediatric clinic in Zagreb. Molecular characterization of HRSV revealed the predominance of HRSV group B viruses in the first two epidemic seasons and HRSV group A viruses in the next two seasons. According to the phylogenetic analysis, NA1 and BA9 were the predominant circulating HRSV genotypes detected during the study. Overall, 82.9% of all HRSV A strains belonged to the NA1 genotype. The HRSV B genotype BA9, detected in two consecutive seasons (2006 and 2007), was the predominant circulating HRSV B genotype, accounting for 80.6% of all HRSV B strains. This study provides data on the circulation pattern of HRSV genotypes in Croatia and their molecular characterization.

The role of IgG avidity in diagnosis of cytomegalovirus infection in newborns and infants.

To evaluate the value of IgG avidity in diagnosis of congenital cytomegalovirus (CMV) infection in newborns and infants we collected serum samples from 40 infants under 12 months of age with suspected congenital CMV infection. Sera were tested for IgM, IgG and IgG avidity. For 25 of them, virus isolation and/or polymerase chain reaction (PCR) on urine specimens were performed. Thirteen (32.5%) patients showed the presence of CMV IgM antibodies, 3 (7.5%) had equivocal IgM result, and 24 (60.0%) patients had IgG antibodies only. Using IgG avidity, CMV infection (low avidity index-AI) was documented in 61.5% IgM positive and 54.2% IgM negative patients. Eight of nine (88.8%) IgM positive patients were positive either on virus isolation or PCR. In IgM negative patients, 46.6% urine cultures were positive for CMV and 66.6% were PCR positive. According to age, IgG avidity demonstrated acute/recent primary CMV infection in 58.8% patients younger than three months compared with 91.7% and 81.8% in 3-6 and 6-12 months old babies, respectively. In conclusion, IgG avidity is useful in diagnosis of CMV infection either in IgM positive or IgM negative children older than 3 months of age. In infants less than 3 months, transplacentally derived maternal IgG antibodies of high avidity influence on the IgG avidity result. In these children, CMV infection should be confirmed by direct virologic methods such as virus isolation or PCR.

Analysis of biennial outbreak pattern of respiratory syncytial virus according to subtype (A and B) in the Zagreb region.

BACKGROUND: The epidemic pattern of respiratory syncytial virus (RSV) in Croatia is biennial. In order to determine if the circulation of different RSV subtypes affects the outbreak cycle, the aim of the present study was to analyze the epidemic pattern of RSV in children in Croatia (Zagreb region) over a period of 3 consecutive years. METHODS: The study group consisted of 696 inpatients, aged 0-5 years, who were hospitalized with acute respiratory tract infections caused by RSV, in Zagreb, in the period 1 January 2006-31 December 2008. The virus was identified in nasopharyngeal secretions using direct immunofluorescence. The virus subtype was determined on real-time polymerase chain reaction. RESULTS: Of 696 RSV infections identified in children, subtype A virus caused 374 infections, and subtype B, 318. Four patients had a dual RSV infection (subtypes A and B). The period of study was characterized by four epidemic waves of RSV infections: the first, smaller, in the spring of 2006; the second, larger, in December 2006/January 2007; the third in spring 2008, followed by a fourth outbreak beginning in November of 2008. The biennial virus cycles were persistent although the predominant RSV subtype in the first two epidemic waves was subtype B, and in the second two it was subtype A. CONCLUSION: Over a 3 year period of observation, the biennial RSV cycle in Croatia cannot be explained by a difference in the predominant circulating subtype of RSV. Other unknown factors account for the biennial cycle of RSV epidemics in Croatia.

Does the viral subtype influence the biennial cycle of respiratory syncytial virus?

BACKGROUND: The epidemic pattern of respiratory syncytial virus (RSV) is quite different in regions of Europe (biennial epidemics in alternating cycles of approximately 9 and 15 months) than in the Western Hemisphere (annual epidemics). In order to determine if these differences are accounted for by the circulation of different RSV subtypes, we studied the prevalence of RSV subtype A and B strains in Zagreb County from 1 January 2006 to 31 December 2007. RESULTS: RSV was identified in the nasopharyngeal secretions of 368 inpatients using direct fluorescence assays and/or by virus isolation in cell culture. The subtype of recovered strains was determined by real-time PCR. Of 368 RSV infections identified in children during this interval, subtype A virus caused 94 infections, and subtype B 270. Four patients had a dual RSV infection (subtypes A and B). The period of study was characterized by two epidemic waves of RSV infections-one, smaller, in the spring of 2006 (peaking in March), the second, larger, in December 2006/January 2007 (peaking in January). The predominant subtype in both outbreaks was RSV subtype B. Not until November 2007 did RSV subtype A predominate, while initiating a new outbreak continuing into the following calendar year. CONCLUSION: Though only two calendar years were monitored, we believe that the biennial RSV cycle in Croatia occurs independently of the dominant viral subtype.

Detection of genetic lineages of human metapneumovirus in Croatia during the winter season 2005/2006.

Human metapneumovirus (HMPV) is an important respiratory pathogen, especially among young children. The genetic characteristics of HMPV circulating in Croatia have not been studied so far. The aim of this study was to determine the incidence of HMPV infection in hospitalized children with acute respiratory tract infection (ARTI) in the season 2005/2006 in Croatia, as well as to perform the genotypic analysis of detected HMPV strains. From December 1 to March 31 nasopharyngeal secretions (NPSs) were collected from 402 inpatients up to 5 years of age with ARTI. NPSs were tested by real-time RT-PCR assay targeting the nucleoprotein (N) gene of HMPV. HMPV infection was detected in 33 patients (8.2%). To perform the phylogenetic study, partial nucleotide sequences were obtained for HMPV fusion (F) gene of 30 HMPV positive samples. Phylogenetic analysis showed the circulation of two main genetic lineages (A and B), with B lineages being prevalent. It also showed the existence of two sublineages within the group B (B1 and B2) and three subclusters within lineage A (A1, A2a and A2b). Further molecular analysis revealed point mutations in HMPV strains of sublineage B1.