Epidemiological typing of Candida albicans from bloodstream infections by restriction enzyme analysis.

Candida albicans blood culture isolates (n = 142) from 130 patients treated in 7 acute care hospitals in Southern Finland between 1986 and 1995 were typed by restriction enzyme analysis (REA) with EcoRI and MspI. REA revealed 118 distinct DNA types: 13 were detected in > 1 patient and 105 DNA types were unique. Patients with identical DNA types were not temporally or geographically clustered. Among 11 patients with more than 1 C. albicans isolate during 1 episode of fungemia the DNA type remained the same, except in 1 patient. These results indicate that REA is a powerful tool for the epidemiological typing of C. albicans infections.

Diagnostic laparoscopy in patients with acute leukemia and suspected hepatic candidiasis.

To assess the value of laparoscopy in the diagnosis of suspected hepatosplenic candidiasis in patients with acute leukemia, a retrospective analysis of 28 laparoscopies was conducted. In all but two cases, imaging of the liver showed focal lesions before laparoscopy. Diagnosis of hepatic candidiasis was established significantly more often when the biopsy was targeted at white nodules (in 12 of 22 laparoscopies) than when targeted randomly or at scars (0 of 6 laparoscopies) (p = 0.017, chi-square test). Yeast was detected more often if the laparoscopy was performed during the three-week period after recovery from neutropenia (in 8 of 12 laparoscopies) than when performed later (in 4 of 16 laparoscopies) (p = 0.028, chi-square test). In addition to the 12 laparoscopically diagnosed patients, eight (29%) patients were diagnosed with disseminated Candida infection by other methods. In another eight (29%) patients the causative agent was not identified. No bleeding or other problems occurred after the laparoscopy. Laparoscopy-guided liver biopsy is most useful if biopsies are targeted to macroscopic lesions and if laparoscopy is performed soon after recovery from neutropenia.

Expression of adhesion molecules on endothelial cells stimulated by Chlamydia pneumoniae.

Previous studies have shown that C. pneumoniae is able to infect human endothelial cells in vitro. In this report, the ability of C. pneumoniae to induce the expression of E-selectin or endothelial-leukocyte adhesion molecule 1 (ELAM-1), intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) on human umbilical vein endothelial (HUVE) cell surface was investigated. C. pneumoniae was found to cause a moderate upregulation of the adhesion molecules. Maximal expression of E-selectin was noted at 6 h post infection (p.i.) and that of ICAM-1 and VCAM-1 at 20 h p.i. The capability of C. pneumoniae to grow in endothelial cells and to stimulate the expression of adhesion molecules essential for leukocyte-endothelial cell interactions suggests a role for C. pneumoniae as a local pathogenetic factor in vascular inflammatory alterations, including atherogenesis.

Growth of Chlamydia pneumoniae in cultured human peripheral blood mononuclear cells and induction of a cytokine response.

In vitro infection of freshly isolated human peripheral blood mononuclear cells (HPBMC) with Chlamydia pneumoniae was found to induce a production of tumour necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and interferon alpha (IFN-alpha). The secretion was dependent on the amount of infecting chlamydiae and most of it occurred during the first 12 to 24 h. Lipopolysaccharide (LPS) of Salmonella minnesota Rechemotype, used as a positive control for HPBMC activation, induced a release of TNF-alpha, IL-1 beta and IL-6, but not of IFN-alpha, similar to the effect of C. pneumoniae. Viable chlamydiae could not be recovered from HPBMCs infected immediately after their isolation, whereas HPBMCs which were cultured in vitro for 3 to 9 days before infection were able to maintain the growth of C. pneumoniae. Growth inside HPBMCs as well as induction of cytokine response may have a role in the pathogenesis of C. pneumoniae infection.

Bacteremia caused by Brevibacterium species in an immunocompromised patient.

A 46-year-old woman suffering from non-Hodgkin's lymphoma was admitted to the hospital because of high fever. Multiple blood cultures revealed an unusual finding, a Brevibacterium species, which was reisolated 16 days later from the tip of her long-term central venous catheter. This case indicates that Brevibacterium species isolated from normally sterile sites should be considered as a potential pathogen, especially in immunocompromised patients.

Report of four cases of Yersinia pseudotuberculosis septicemia and a literature review.

Yersinia pseudotuberculosis is a rare cause of disease in humans, the most common manifestation being mesenteric lymphadenitis accompanied by abdominal pain and fever. A septicemic form of Yersinia pseudotuberculosis infection has been reported only rarely. It is usually seen in patients with underlying disorders such as diabetes, hepatic cirrhosis or iron overload. Fifty-four cases of septicemic infection were found in the literature. The earlier published cases are reviewed, and four cases occurring in Finland during the period February to June 1992 are reported.

Chlamydia pneumoniae multiplies in human endothelial cells in vitro.

The ability of three C. pneumoniae isolates, Kajaani 6, Helsinki 12 and TW-183, to grow in human umbilical vein endothelial cells (HUVEC) and in an immortalized endothelial cell line EA.hy 926 was studied. All C. pneumoniae isolates were capable of multiplying in endothelial cells. EA.hy926 cells could support the growth of C. pneumoniae better than HUVEC, yet less efficiently than HL and HEp-2 cells that are conventionally used in C. pneumoniae culturing. Although centrifugation of the inoculum greatly increased the inclusion yields, it was not necessary for infectivity. In addition, a persistent infection of C. pneumoniae in EA.hy 926 and HL cells ensued and it was followed up for two months. The fact that endothelial cells can serve as hosts to C. pneumoniae might be a significant contributing factor in the pathogenesis of atherosclerosis, a disease which recent studies show to be associated with chronic C. pneumoniae infection.

Experimental infection of Chlamydia pneumoniae in mice.

NIH/S, Swiss Webster, and BALB/c mice were infected intranasally with three Chlamydia pneumoniae isolates, Kajaani 6, Helsinki 12, and TW-183. C. pneumoniae could be isolated from the lung homogenates and bronchoalveolar lavage fluids up to the third week post-infection. Specific serum IgG antibodies against C. pneumoniae reached high levels in the third week and remained elevated until the end of the 6-week follow-up period. Serum IgM levels were highest in the third week post-infection and started to decrease thereafter. In spite of these signs of ongoing infection, the mice did not show any symptoms of disease. NIH/S mice could be readily and uniformly infected, while BALB/c mice were the most resistant and developed the weakest antibody response. The greatest histological changes were detected in NIH/S mice as well. The inflammatory infiltrate, which consisted of lymphocytes and plasma cells throughout the study, was restricted to the peribronchial and perivascular space and to the interstitium of the lung parenchyma.

Effect of erythromycin acistrate and erythromycin stearate on human colonic microflora.

The effects of erythromycin acistrate (2'-acetyl erythromycin stearate), a new erythromycin derivative, and erythromycin stearate on the faecal microflora were compared in a randomized cross-over study. 12 healthy volunteers were given either drug 500 mg t.i.d. for 1 week. Their faeces were studied before, immediately after, and 1 week after the drug administration period. After a wash-out period of 4 weeks, the drugs were interchanged. Both erythromycin acistrate and erythromycin stearate induced changes in the normal colonic microflora to about the same extent. The most marked effect was the suppression of gram-negative anaerobic and aerobic rods. Clostridium difficile appeared in 1 subject on both drugs. Also the counts of aerobic gram-positive cocci were altered; enterococci increased in number. An increased resistance to erythromycin was noted among staphylococci and enterococci after both drugs.