Adherence of Irradiated Slime Producing Bacterial Pathogens to Biomaterial Surface and their Antimicrobial Susceptibility Associated with Catheter Infection in Bladder Cancer Patients.

Aims: To detect the prevalence of biofilm producers among Gram negative bacilli and Gram positive cocci bacterial pathogens along with their antimicrobial susceptibility pattern. Growth and adherence on catheter eluates and in the presence of antibiotics. Methodology: From laboratory of microbiology, one hundred samples (100 urinary catheters and 100 urine samples from the attached drainage bags) of bladder cancer patients collected in National Cancer Institute in Cairo, Egypt, were identified to species level. Slime production was investigated by the quantitative and qualitative methods. Qualitative method was carried out by tube method. Adherence assay and quantitation of biofilm was performed by spectrophotometric method by measuring the optical densities of stained bacterial films adherent to plastic tissue culture plates. Hydrophobicity was evaluated by adhesion to P-xylene. Identification and minimum inhibitory concentration (MICs) of 26 antimicrobial agents against gram negative and 24 against gram positive bacterial isolates were determined using microscan walk away 96 SI system. Plasmid profile analysis was carried out by plasmid isolation kit. Scanning electron microscopy studies for growth, adherence and biofilm formation. Impact of gamma irradiation at a dose level of 24.41Gy was studied. Results: From the processing of 100 samples, 98 cases were positive. Out of them 110 isolates of gram negative bacilli and 13 of gram positive cocci. They were belonging to 15 and 6 species respectively. Among them, 117 isolates showed positive results for adherence assay and biofilm/slime production. They were identified as; Escherichia coli, Klebsiella spp., Enterobacter spp., Acinetobacter, Proteus spp., Citrobacter, Alcaligenes, Empedobacter (104 strains) Staphylococcus spp. and Enterococcus (13 stains). The results obtained by different methods correlated well with strain to strain variation. Gamma irradiation resulted in changes in slime production and adherence ability for all the tested strains. Cell surface hydrophobicity (CSH) showed a hydrophobic reaction and these with increase in its value after irradiation in case of Escherichia coli. On the other hand, Staphylococcus epidermidis was moderate hydrophobic before irradiation changed to strictly hydrophilic after irradiation. All the slime producers showed reduced susceptibility to majority of antibiotics. They exhibited highest percentage susceptibility before and after in vitro gamma irradiation at a dose level 24.41Gy for both Amikacin and Imipenem. Scanning electron microscopy (SEM) confirmed growth and biofilm formation in the presence of catheter eluates only with halos surrounding the cells and visible erosion zones on catheter surfaces. The antimicrobial and adherence activity of Amikacin and Imipenem at the MIC level showed marked abnormalities in cells shape and size with significant reduction in adherence ability. Plasmid profile analysis of irradiated strains showed more extra-plasmid bands and / or difference in molecular weight. Conclusion: The biofilm assay strategy applied in this study may constitute a tool in biomaterial related infection and antimicrobial resistant research for further studies for biomaterial modification. Early detection of biofilm forming organisms can help in appropriate antibiotic choice.

periodontitis an occult source of recurrent infection in patients with systemic lupus erythematosus?

To determine if periodontitis can be considered as an occult source and septic focus for recurrent infections in patients with Systemic lupus erythematosus [SLE]. The present study was conducted on 60 subjects divided into 4 groups. Group 1: included 30 SLE patients with periodontitis [SLE/P]. They were further subdivided according to the CRP titer into: Group 1A: 20 patients with CRP titer > 6 and Group 1B: 10 patients with CRP titer < 6. Group 2: included 10 SLE patients without periodontitis [SLE/X], Group 3: 10 non SLE subjects with periodontitis [X/P] and lastly Group 4: 10 healthy subjects. SLE disease activity was assessed by SLAM score. Periodontal examination was assessed by periodontal disease index [PDI]. Laboratory investigations: serum [s] and salivary [sal] CRP titre, CBC, ESR and urine analysis. Microbiological examination of plaque specimens was done. Comparative study between Group 1A and Group 3 revealed a highly significant difference as regards PDI and a significant difference as regards WBC count, ESR, s/CRP, sal/CRP titre indicating more severe periodontal disease in patients with SLE. There was a highly significant greater severity of periodontal disease in patients additionally receiving immunosuppressive therapy. The plaque culture showed Streptococci, Klebsiella, Staphylococci, E. coli and Pneumococci. In selected patients from Group 1, there was a highly significant decrease of s/CRP and sal/CRP after periodontal treatment. Periodontitis is an occult infection that can be considered as a septic focus in SLE patients. CRP is a sensitive indicator for the presence of infection in SLE patients. Periodontal examination must be done routinely for all SLE patients

Neopterin in pulmonary tuberculosis and lung cancer patients

Neopterin is produced and released by human macrophages in response to stimulation with interferon-gamma, and changes in neopterin concentrations indicate cellular immune activation. To assess the usefulness of serum, urine and pleural fluid neopterin levels as an index of disease activity in patients with pulmonary tuberculosis and lung cancer. Serum, urine and pleural fluid neopterin levels were evaluated in 30 patients with pulmonary tuberculosis and 30 patients with lung cancer while serum and urine neopterin levels were evaluated in 20 healthy controls by enzyme linked imunosorbent assay [ELISA] technique. The neopterin levels [mean +/- SD] in the serum and urine of 30 tuberculous patients [54 +/- 13.9 n mol/L, 675 +/- 230.7 n mol/mol criatinine respectively] were significantly higher when compared with those in lung cancer patients [29 +/- 5 n moUL, 312 +/- 74.5 n mol/ mol criatnine respectively, P < 0.001] and when compared with those in control subjects [6 +/- 2 n mol/L, 128 +/- 39.8 u mol/mol criatinine respectively]. In tuberculosis patients with faradvanced disease pleural fluid, serum and urine neopterin levels were significantly higher when compared with those in patients with moderately and minimally advanced disease [p < 0.001]. In lung cancer group serum and urine neopterin levels were significantly higher [p < 0.001] in adenocarcinoma, squanous cell carcinoma, and small cell carcinoma than that in the control group. But there was no significant difference between the serum, urine and pleural fluid neopterin from one cell type to another. Serum urine and pleural fluid neopterin levels may reflect the degree of activity in pulmonary tuberculosis before exact diagnosis of the disease by culture results. In addition serum, urine and pleural fluid neopterin levels are elevated in patients with lung cancer whatever the cell type

Hepatocyte growth factor in serum and bronchoalveolar lavage fluid versus exhaled nitric oxide in systemic lupus erythematosus

The present study tried to evaluate the clinical significance of hepatocyte growth factor [HGF] in the serum and bronchoalveolar lavage fluid [BALF] in systemic lupus erythematosus [SLE] patients and their relation to nitric oxide [NO] in exhaled air. Forty SLE patients were investigated along with ten apparently healthy individuals. The patients' group was divided into two groups: group [A] Inactive SLE patients without pulmonary affection [n=14] and group [B] SLE patients with pulmonary affection [n=26]. The last group was further classified into 4 sub groups: - B1= Active SLE patients without interstitial lung disease [ILD], B2= Active SLE patients with interstitial lung disease + Alveolitis [ILD +A], B3: Inactive SLE patients without ILD and B4= Inactive - SLE patients with ILD. All patient and control groups were evaluated for chest X-ray, pulmonary function tests and high-resolution computerized tomography [HRCT], along with systemic lupus erythematosus [SLE routine laboratory investigations. Measurement of HGF Levels in serum and BALF by Immunoassay and exhaled nitric oxide [NO] was measured by chemiluminescence. There were abnormal pulmonary function tests in 65% [26/40] of SLE patients and abnormal HRCT in the form of ILD in 32.5[13/40] of SLE patients. The exhaled NO showed a significant elevation in patients with activity especially those with evidence of active inflammation of the lung. There was no significant elevation of exhaled NO for patients with ILD without evidence of active inflammation. The level of HGF in serum and BALF showed a significant elevation in patients with activity especially with the presence of active lung inflammation. Also, there was a significant elevation of serum HGF and BALF-HGF for patients with ILD without evidence of inflammation. The level of HGF in serum and BALF showed significant elevation in patients as compared with control subjects. HGF levels in BALF of patients was more elevated than HGF levels in serum of patients groups. HGF in serum and BALF was increased in patients with pulmonary fibrosis and correlated with clinical parameters. Measurement of exhaled NO is a simple and non-invasive method to detect the presence of inflammatory lung disease