Biljana Miljkovic-Selimovic

Helicobacter pylori: An Underestimated Factor in Acute Anterior Uveitis and Spondyloarthropathies?

Acute anterior uveitis (AAU) is the most common form of intraocular inflammation, but its aetiology is still unclear. Fifty percent of AAU patients are HLA-B27-positive, and half of these also have spondyloarthropathies (SpA). Numerous serological studies have shown elevated levels of serum antibodies to various Gram-negative bacteria in HLA-B27-positive AAU and SpA patients. Antigenic similarities between these bacteria and host components (HLA-B27) have already been shown. Still, the mechanism underlying these diseases has not been clarified. Among the Gram-negative bacteria, Helicobacter pylori has not been screened in AAU patients. The purpose of our study was to see if this common human pathogen somehow interferes with AAU. In addition Chlamydia trachomatis, Yersinia enterocolitica 03 and 09, Salmonella sp. and Proteus OX19 were also examined. A total of 60 patients consisting of 4 groups (15 patients with AAU, 15 with SpA, 15 with AAU+SpA and 15 healthy control persons) were examined. A high percentage of the serological results of all investigated bacteria was positive: 80% in the AAU, 93.3% in the SpA and 100% in the AAU+SpA group, while it amounted to 66.7% in the control group (p < 0.05). H. pylori showed the highest percentage of positivity in all 3 patient groups (66.7% in the AAU, 73.3% in the SpA and 80% in the AAU+SpA group). In contrast, 26.7% of the controls were anti-H.-pylori-positive, thus showing a statistically significant difference between the patients and the control group (p < 0.05). HLA-B27/B7-CREG positivity was detected in 53.3% of the AAU, 66.7% of the SpA and 93.3% of the AAU+SpA patients and in none of the controls. Our results suggest that H. pylori might be a candidate participating in the development of AAU and SpA. They also support the theory of genetic (HLA-B27) and exogenous factors (Gram-negative bacteria) as probable background of these diseases.

High-density cervical ureaplasma urealyticum colonization in pregnant women

BACKGROUND/AIM Ureaplasma urealyticum, a common commensal of the female lower genital tract, has been observed as an important opportunistic pathogen during pregnancy. The aims of this study were to determine the degree of cervical colonization with U. urealyticum in pregnant women with risk pregnancy and in pregnant women with normal term delivery and to evaluate the correlation between high-density cervical U. urealyticum colonization and premature rupture of membranes (PROM) as well. METHODS This research was conducted on the samples comprizing 130 hospitalized pregnant women with threatening preterm delivery and premature rupture of membranes. The control group consisted of 39 pregnant women with term delivery without PROM. In addition to standard bacteriological examination and performing direct immunofluorescence test to detect Chlamydia trachomalis, cervical swabs were also examined for the presence of U. urealyticum and Mycoplasma hominis by commercially available Mycofast Evolution 2 test (International Microbio, France). RESULTS The number of findings with isolated high-density U. urealyticum in the target group was 69 (53.08%), while in the control group was 14 (35.90%). Premature rupture of membranes (PROM) occurred in 43 (33.08%) examinees: 29 were pPROM, and 14 were PROM. The finding of U. urealyticum > or = 10(4) was determined in 25 (58.14%) pregnant women with rupture, 17 were pPROM, and 8 were PROM. There was statistically significant difference in the finding of high-density U. urealyticum between the pregnant women with PROM and the control group (chi2 = 4.06, p < 0.05). U. urealyticum was predominant bacterial species found in 62.79% of isolates in the PROM cases, while in 32.56% it was isolated alone. Among the 49 pregnant women with preterm delivery, pPROM occurred in 29 (59.18%) examinees, and in 70.83% of pregnant women with findings of high-density U. urealyticum pPROM was observed. CONCLUSION Cervical colonization with U. urealyticum > or = 10(4) is more frequent in pregnant women with risk pregnancy than in pregnant women with normal term delivery. High-density cervical U. urealyticum colonization should be observed as a possible etiological factor for PROM.

Enteritis caused by Campylobacter jejuni followed by acute motor axonal neuropathy: a case report

IntroductionCampylobacter species represent the main cause of bacterial diarrhea in developed countries and one of the most frequent causes of enterocolitis in developing ones. In some patients, Campylobacter jejuni infection of the gastrointestinal tract has been observed as an antecedent illness of acute motor axonal neuropathy, a variant of Guillain-Barré syndrome.Case presentationWe present a case of acute motor axonal neuropathy following infection with Campylobacter jejuni subspecies jejuni, biotype II, heat stable serotype O:19. A 46-year-old Caucasian man developed acute motor neuropathy 10 days after mild intestinal infection. The proximal and distal muscle weakness of his upper and lower extremities was associated with serum antibodies to Campylobacter jejuni and antibodies to ganglioside GM1. The electromyographic signs of neuropathic muscle action potentials with almost normal nerve conduction velocities indicated axonal neuropathy. Our patients clinical and electrophysiological features fulfilled criteria for the diagnosis of an acute motor axonal neuropathy, a subtype of Guillain-Barré syndrome.ConclusionAs this is the first case of acute motor axonal neuropathy following infection with Campylobacter jejuni subspecies jejuni reported from the Balkan area, the present findings indicate the need for systematic studies and further clinical, epidemiological and microbiological investigations on the prevalence of Campylobacter jejuni and its heat stable serotypes in the etiology of Guillain-Barré syndrome and other post-infectious sequelae.

Staphylococcus aureus: Immunopathogenesis and Human Immunity

Summary Considering a large number of pathogen factors that enable high virulence of a microorganism such as Staphylococcus aureus (S. aureus), it is essential to see them through the continuous adaptation to the newly acquired mechanisms of the host immune response and efforts to overcome these, allowing the bacteria a perfect ecological niche for growth, reproduction, and location of new hosts. Past efforts to create a vaccine that would provide effective protection against infections caused by S. aureus remained without success. The reasons for this stem from the outstanding adaptability skills of this microorganism to almost all environmental conditions, the existence of a numerous virulence factors whose mechanisms of action are not well known, as well as insufficient knowledge of the immune response to S. aureus infections. This review article deals with this issue from another perspective and emphasizes actual knowledge on virulence factors and immune response to S. aureus. Sažetak Brojni su faktori patogenosti koji omogućavaju visok stepen virulencije mikroorganizmu poput Staphylococcus aureus (S. aureus). Posebno je važno sagledati faktore sposobnosti stalne adaptacije na mehanizme imunskog odgovora domaćina, što bakteriji omogućava idealnu ekološku nišu za rast, razmnožavanje i širenje. Dosadašnji napori da se dođe do vakcine koja bi omogućila efikasnu zaštitu od infekcija izazvanih S. aureusom ostali su bez uspeha. Razlozi za ovakvu situaciju se nalaze u izraženoj adaptaciji ovog mikroorganizma na gotovo sve uslove spoljašnje sredine, u postojanju velikog broja faktora virulencije čiji mehanizmi delovanja nisu dovoljno poznati, kao i nedovoljnog poznavanja imunskog odgovora na infekciju S. aureus. Svrha ovog rada je da se sa novijih aspekata sagleda navedena problematika i istaknu savremena saznanja o faktorima virulencije i imunskom odgovoru na S. aureusu.

Survival of Campylobacter jejuni in chicken meat at frozen storage temperatures

The aim of this study was to determine the survival of Campylobacter jejuni in chicken meat samples at frozen temperatures and given length of incubation and to determine the impact of aerobic bacteria on the survival of C. jejuni. The chicken meat samples were inoculated with C. jejuni NCTC 11351 suspensions and stored in bags at temperatures of -20°C and -70°C. The mean value of C. jejuni from meat samples decreased from 7.52 log10 CFU/g after 30 minutes of incubation at ambient temperature, to 3.87 log10 CFU/g on the eighth week of incubation at -20°C, and to 3.78 log10 CFU/g at incubation at -70°C after the same incubation period. Both freezing temperatures, -20°C and -70°C, decreased the number of campylobacters. The presence of aerobic mesophilic bacteria did not influence the survival of C. jejuni in chicken meet samples. Keeping poultry meat at freezing temperatures is important for the reduction of C. jejuni, which has a strong influence on the prevention of occurrence of campylobacteriosis in humans.

Frequency of antimicrobial resistance in thermophilic campylobacter strains from humans, poultry and pigs

Uþestalost antimikrobne rezistencije termofilnih Campylobacter sojeva poreklom od ljudi, živine i svinja

Resistance in Staphylococcus Aureus: The Never-Ending Story

Summary Combating Staphylococcus aureus (S. aureus) infections using antibacterial drugs is actually an ongoing effort to overcome resistance mechanism of this microorganism. In this paper, we discussed (1) the mechanisms of resistance to some of the most commonly used antimicrobial agents in the treatment of S. aureus: methicillin, vancomicyn and quinolones. In addition, (2) efflux pump mechanisms involved in maintaining homeostasis in the presence of compounds that inhibit S. aureus growth and reproduction, as well as mechanisms of resistance to a number of antibiotics, have been reviewed.