Agnieszka Sikora

Prevalence of Legionella pneumophila in water distribution systems in hospitals and public buildings of the Lublin region of eastern Poland.

OBJECTIVE The aim of this study was to determine the prevalence of L. pneumophila in water supply systems, hospitals and public buildings in the Lublin region of eastern Poland. MATERIAL AND METHODS The study was carried out in 26 different objects in the Lublin region. The number of Legionella bacteria in water samples was determined by the membrane filtration method and/or by surface inoculation in accordance with the standards. RESULTS The study showed the presence of L. pneumophila in 166 hot water samples (74.77%). In 34.33% (n=57) of water samples the count of tested bacteria exceeded the acceptable level of >100 CFU/100 ml. Of the samples where an acceptable level of bacteria was exceeded, 49 samples had an average level of L. pneumophila (100-1,000 CFU/100 ml), and the level in 8 samples was high (>1,000 CFU/100 ml). CONCLUSIONS The water samples collected form the hot water supply system of hospitals and public buildings showed exceeded counts of L. pneumophila, indicating the risk of infection. The constant monitoring of water distribution systems is an important element of the control of infections caused by these organisms.

Assessment of cytokine release after in vitro stimulation of whole blood with legionella pneumophila in immunocompromised patients.

This study we examined ex vivo potential of the immune response after stimulation of whole blood with L. pneumophila SG 1, SG 2-14 and L. pneumophila standard strain ATCC 33152 in immunocompromised patients, such as: hemodialysis patients and patients after renal transplantation. The levels of TNF-α and IFN-γ in supernatants were measured with the use of commercial ELISA kits. The synthesis of TNF-α and IFN-γ after stimulation with L. pneumophila were analyzed in two aspects: differentiated stimulatory activity in relation to SG 1, SG 2-14 and ATCC 33152 L. pneumophila and differentiated response of the hemodialysis patients and patients after renal transplantation in relation to the control group. The positive and negative results of anti-L. pneumophila antibodies of two groups of our patients were found for the analysis of the stimulatory activity of L.pneumophila as a primary or secondary response. In patients with immunosuppression the response in the secretion of cytokines (TNF-α and IFN-γ) was reduced after stimulation of L. pneumophila SG 1 but in varying degrees after stimulation of L. pneumophila SG 2-14, which indicates that the risk of the infection is varied.

Prevalence of Legionella antibodies in immunocompromised patients

IntroductionDialysis patients and patients post-renal transplantation can be predisposed to Legionella infections. The aim of this work was to investigate the prevalence of L. pneumophila serogroups 1–7 (SG 1–7) antibodies in dialysis patients and in patients following renal transplantation, in order to analyse the potential risk factors for infections.Material and MethodsCommercial ELISA kits were used for detection of serum IgG (SG 1–7, SG 1) and IgM (SG 1–7) present in patients and the control group. Results: In the studied group of patients, positive results (IgM and/or IgG SG 1–7) were obtained in 20 patients (7.12%). One patient only had two classes of antibodies. From the total study group, the antibodies against L. pneumophila SG 1 were detected in only one patient on dialysis. Patients with L. pneumophila antibodies who are on dialysis or post-renal transplantation did not differ significantly in any of the usually evaluated risk factors of clinical infection.ConclusionsThe reported outbreaks of Legionnaires’ disease in chronic dialysis patients and those with renal transplants, as well as our results of IgG and IgM antibodies, merit further identification of the sources of this infection but also the ways in which cellular immune system can be managed in the immunocompromised patients with Legionella infection.

Zakażenia Streptococcus agalactiae u kobiet ciężarnych i noworodków

Streptococcus agalactiae (group B Streptococcus – GBS) is a pathogenic factor of infections during pregnancy, the postpartum period and neonatal infections. The main risk factor for infection during the neonatal period is GBS colonization of the vagina and rectum of the mother. Neonatal infection with group B Streptococcus may occur in the form of severe pneumonia, meningitis and sepsis. In pregnant women we observe: asymptomatic bacteriuria, bacteraemia after the caesarean section and chorioamnionitis. Screening for group B Streptococcus in women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis in GBS-positive pregnant women are considered to be the most effective methods of preventing neonatal infections.