Molecular characteristics of Neisseria meningitidis carriage strains in university students in Lithuania.

BACKGROUND: Neisseria meningitidis can be carried asymptomatically in the human oropharynx without causing symptoms. Meningococcal carriage is relevant to the epidemiology of invasive meningococcal disease (IMD). No carriage studies have been performed among the general population in Lithuania, whereas the incidence of IMD in Lithuania was among the highest in European countries from 2009 to 2019. RESULTS: We analyzed a total of 401 oropharyngeal samples collected from university students from December 2021 to February 2023 for N. meningitidis carriage using direct swab PCR assays and culture. The overall carriage prevalence based on both or either swab PCR or culture was 4.99%. PCR-based assays were used to characterize 15 carriage isolates, including detection of genogroup, multilocus sequence typing profile, and typing of antigens PorA and FetA. The most common carriage isolates were capsule null locus (cnl), accounting for 46.7%, followed by genogroups B (26.7%) and Y (13.3%). We also performed a molecular characterization of invasive N. meningitidis isolates collected during the COVID-19 pandemic and post-pandemic period to understand better the meningococcal carriage in the context of prevailing invasive strains. Despite the substantial decrease in the incidence of IMD during the 2020-2022 period, clonal complex 32 (CC32) of serogroup B continued to be the most prevalent IMD-causing CC in Lithuania. However, CC32 was not detected among carriage isolates. The most common CCs were CC269, CC198, and CC1136. The antigen peptide variants found in most carried isolates were classified as 'insufficient data' according to the MenDeVAR Index to evaluate the potential coverage by the 4CMenB vaccine. Nearly half of the isolates were potentially covered by the Men-Fhbp vaccine. Resistance to ciprofloxacin was detected only for one cnl isolate. All isolates were susceptible to penicillin and ceftriaxone. Our analysis identified frequent partying (≥ 4 times/month) as a risk factor for meningococcal carriage, whereas smoking, living in a dormitory, and previous COVID-19 illness were not associated with the carriage. CONCLUSIONS: Our study revealed a low prevalence of meningococcal carriage among university students in Lithuania. The carriage isolates showed genetic diversity, although almost half of them were identified as having a null capsule locus.

The use of vaginal wet smear: can we predict Mycoplasmas/Ureaplasmas?

PURPOSE: To evaluate the agreement of wet smear microscopy with Gram stain microscopy and to assess whether it is possible to predict Mycoplasmas/Ureaplasmas when analysing vaginal secretion with Gram stain and wet smear microscopy. METHODS: Women with complaints of the abnormal vaginal discharge were invited to participate. A sample of vaginal secretion was taken for wet smear microscopy and for Gram staining analysis. A sample from the endocervical canal was taken for DNA detection of seven infections: Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma parvum, Ureaplasma urealyticum, Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis. The percentage agreement between wet smear and Gram stain was determined and the Cohen's Kappa values were calculated. RESULTS: Of 158 consecutive women included, one (or a few) of the infections were detected in 54% of them and the most frequent infection was Ureaplasma parvum (79% of all the cases with infections). The percentage agreement between vaginal wet smear and Gram stain was 73% (Cohen's Kappa value 0.63). A statistically significant association between the DNA detected Mycoplasmas/Ureaplasmas and bacterial vaginosis was found (positive amine test p = 0.046, wet smear p = 0.005 and Gram stain p = 0.03). CONCLUSIONS: There was a statistically significant association between bacterial vaginosis and the DNA detected Mycoplasmas/Ureaplasmas. The agreement of vaginal wet smear with Gram stain was good.

Etiological profile of hearing loss amongst Lithuanian pediatric cochlear implant users.

INTRODUCTION: Congenital sensorineural hearing loss is a heterogeneous disorder; its etiological profile varies between populations. Pathogenic variants of GJB2 gene are the major cause of non-syndromic hearing loss. Congenital cytomegalovirus infection (cCMV) is the most important prenatal etiological factor causing hearing loss and other disorders. Perinatal events, syndromes, postnatal infections or traumas are less common. Causes of the remaining one third of hearing loss cases are unknown. OBJECTIVES: To determine the etiological profile of hearing loss in pediatric cochlear implant users in Lithuanian population. METHODS: The data of 122 children (70 male/52 female; aged 7.6 ± 3.3 years) cochlear implant users were analysed. Medical records of all children recruited in Santaros Clinics (Vilnius, Lithuania) were analysed to identify prenatal, perinatal, or postnatal risk factors based on the adapted list proposed by the Joint Committee of Infant Hearing. Genetic counselling and testing according to the scheme were performed to 101 children. DNA of 117 children was extracted from the DBS on Guthrie cards and CMV DNA detected using real time PCR. RESULTS: Non-syndromic hearing loss was diagnosed in 65 cases (53.3%), 58 of which were GJB2 gene-associated; syndromic hearing loss was diagnosed to 8 children (6.6%). Perinatal (prematurity, low birth weight, hypoxia, hyperbilirubinemia, sepsis, ototoxicity, and meningitis) and postnatal (meningitis) risk factors were associated with hearing loss in 16 (13.1%) and 4 (3.3%) study participants respectively. CMV DNA was detected in 12 samples (9.8%). The cause of hearing loss remained unknown only for 17 (13.9%) children. CONCLUSIONS: The major cause of HL in the current study was GJB2 gene alterations. Only 14% of the cohort had congenital hearing loss of unknown origin.

Candida Distribution in Onychomycosis and in vitro Susceptibility to Antifungal Agents.

The aim of this study was to determine distribution of the Candida (C.) species in onychomycosis and analyses in vitro susceptibility to fluconazole and itraconazole. In recent years, cases of onychomycosis in Lithuania caused by Candida have increased significantly. In the period between 2009 and 2016, a total of 8149 clinical cases (outpatients and inpatients) were investigated at the Vilnius University Hospital Santaros Clinics (VUH SC). Candida yeasts were identified using VITEK 2 (BioMerieux, France) and IVD Maldi biotyper 2.3 (Bruker Daltonik GmbH, Germany), automated systems for identification of yeasts. The antifungal susceptibility to the Candida species were determined by disc diffusion. Candida spp. were the most frequently isolated pathogens in onychomycosis during the investigation period. The main species in onychomycosis were C. albicans (38.6%), followed by C. krusei (33.7%), C. tropicalis (11.1%), C. parapsilosis (7.9%), and other Candida (8.7%). The different antifungal susceptibility patterns among Candida species confirm the need to perform antifungal susceptibility in vitro testing of yeasts from patients with onychomycosis.

A case of successfully treated relapsing peritoneal dialysis-associated peritonitis caused by Gordonia bronchialis in a farmer.

Gordonia species are aerobic, weakly acid-fast, Gram-positive pathogens that rarely cause human infections, usually in immunocompromised patients. It is uncommon bacilli in cases of peritoneal dialysis-related peritonitis. The small number of infections with Gordonia species reported for humans may be stipulated by the difficulty in identifying the organism using conventional techniques. Careful review of Gram stains and modified-acid-fast stains should be done, so that confusion with other actinomycetes is minimized, pending the genotypic identification. Here we report a case that was caused by Gordonia bronchialis and thus required different considerations of treatment.