GyrA sequence-based typing of Legionella.

Comparative sequence analysis of a 423-bp segment of the gyrA gene including a region homologous to the quinolone resistance-determining region (QRDR) of other species was evaluated as a novel typing method for Legionella strains. The study was performed with 29 reference strains representing 11 different Legionella species, with various serogroups, and with 13 clinical isolates of L. pneumophila. Pulsed-field gel electrophoresis and serotyping were employed for comparison of the clinical isolates. QRDR sequencing proved to be a highly discriminative tool for typing Legionellae, and permitted identification of species, serogroups and even different strains within serogroup 1. None of the isolates were resistant to quinolones in vitro and this correlated with dissence of mutations in the QRDR region. The data show that comparative sequence analysis of a short fragment of the gyrA gene is a potentially useful tool for typing of Legionella beyond the serogroup level. It is anticipated that mutations of the QRDR may arise in Legionella as a consequence of the introduction of quinolones as the agents of choice for the treatment of infections with this agent in immunocompromised patients. The employment of QRDR-typing maybe helpful in uncovering such mutations.

Simultaneous identification of campylobacters and prediction of quinolone resistance by comparative sequence analysis.

Comparative sequence analysis of a 30-bp segment in the quinolone resistance-determining region of campylobacters not only allows for the detection of base changes associated with resistance but also is a powerful tool for species identification based on silent mutations.

Preoperative application of glucocorticosteroids efficaciously reduces the primary immunological response in kidney transplantation.

Early acute rejection episodes have a considerable influence on long-term prognosis of renal transplants. Therefore the aim of primary immunosuppressive therapy must be effective suppression of the immunological response following antigen recognition. Owing to their pharmacological properties, intravenously given glucocorticosteroids are suitable for the alteration of the primary immunological response. However, even after intravenous administration, glucocorticosteroids have a latency of hours prior to reaching maximum activity. In a prospective clinical study, 111 patients undergoing renal transplantation were preoperatively treated with 500 mg methylprednisolone for immunosuppressive induction. A historical group of 40 patients who had received the same dose as intraoperative bolus, was used for comparison. Postoperative immunosuppression did not substantially differ between the two groups. The incidence of acute rejections within 30 d after transplantation was a clinical parameter of the study. The mitogenic cytokine induction was measured in blood samples which were collected intraoperatively and on days 1, 2, and 5 after transplantation. Cytokine release served as an in vitro parameter for the immunological responsiveness of the transplant recipient. In the group under study, the incidence of acute rejections was 21% (23/111) and, in contrast, 43% (17/30) in the historical group (p < 0.05). 89% of the patients in the group being studied showed normal renal function after 1 yr, compared to 78% in the reference group (n.s.). Following preoperative (mean 5.09 h) administration of glucocorticosteroids, mitogenic cytokine induction (IL-1 beta, IL-2, sIL-2R and IFN-gamma) was almost completely blocked at the time of transplantation. A prospective, randomized study has just been started to evaluate the effect of preoperative administered glucocorticosteroids on the incidence of acute rejections and long-term allograft survival.

Case of fatal systemic infection with an Aureobacterium sp.: identification of isolate by 16S rRNA gene analysis.

The case of a 75-year-old man who succumbed to a disseminated infection most likely caused by a species of the genus Aureobacterium is reported. Identification of the isolate was achieved by comparative 16S rRNA gene analysis. Aureobacteria are commonly found in the environment. However, only recently have they been recognized as a cause of infections including septicemia and soft tissue infections. To our knowledge, this is the first documentation of a fatal infection caused by an Aureobacterium sp.

Infection of the upper extremity by Mycobacterium marinum in a 3-year-old boy--diagnosis by 16S-rDNA analysis.

A 3-year-old boy developed several subcutaneous nodular lesions on his right arm. Based on the histological examination of one of these nodules furunculosis was suspected and cefuroxime was tentatively given. However, acid-fast bacilli were then detected in the tissue specimen and a few colonies of acid fast, gram-positive rods grew on blood agar. Definitive species diagnosis (Mycobacterium marinum) was rapidly achieved by automated sequencing of amplified 16S-rDNA and antimicrobial therapy was adjusted according to the available literature. After 3 weeks of treatment with clarithromycin, rifampicin and protionamid regression of the nodular lesions was evident.

[The von Hippel-Lindau syndrome. Its differential diagnosis from cystic kidneys in adulthood]. / Das v. Hippel-Lindau-Syndrom. Differentialdiagnose von Zystennieren im Erwachsenenalter.

A 51-year-old patient with severe back pain had undergone resection of a benign cerebellar tumour when aged 15 years. In addition, polycystic kidney disease was diagnosed 24 years ago, bilateral phaeochromocytoma 2 years ago, and for 4 months before the present admission he had been on haemodialysis. The family history indicated autosomal dominant inheritance of the polycystic renal disease. His general condition was found to have deteriorated, he had pain on pressure over the upper thoracic and lower lumbar vertebrae, and the kidneys were enlarged on palpation. There were increased concentrations of calcium (3.01 mmol/l), parathormone (2.0 ng/l), carcinoembryonic antigen (13.5 micrograms/l) and TPA (69 U/l). Computed tomography demonstrated cystic and solid parts of much enlarged kidneys. Biopsy revealed a poorly differentiated clear-cell renal carcinoma. Further information concerning the previously removed brain tumour showed this to have been an haemangioblastoma of the cerebellar tonsils indicating the diagnosis of v. Hippel-Lindau disease. Nine other family members had been affected, but none had the full-blown picture of the disease. The patient died 3 weeks later from the rapidly advancing tumour. Autopsy showed the bilateral renal carcinoma, bilateral phaeochromocytoma and metastases to the sternum, femurs, vertebrae and liver.

[C-reactive protein in the urine. The differential diagnosis of renal functional disorders following kidney transplantation]. / C-reaktives Protein im Urin. Differentialdiagnose renaler Funktionsstörungen nach Nierentransplantation.

A prospective study was undertaken in 73 patients (24 women, 49 men; mean age 47.9 [21-64] years) after renal transplantation to discover whether the presence of C-reactive protein in urine (CRPu) and its serum concentration (CRPs) are of value in the differential diagnosis of abnormal function in the transplanted kidney. CRPu concentration was measured with a highly sensitive immunoluminometric assay (minimal threshold value 6 micrograms/l). CRPu was demonstrated in 36 histologically proven rejection episodes and 21 bacterial infections proven by culture. In contrast, no CRPu was demonstrated when the course was normal and in individual cases of cyclosporin renal toxicity, as well as in 27 of 34 cases of cytomegalovirus infection. In addition, the CRPs to CRPu ratio was a sensitive means of distinguishing between rejection (CRPs/CRPu less than 1) and bacterial infection (CRPs/CRPu greater than 1). Determining CRPu concentration thus proved to be useful in the initial monitoring of renal transplantation before starting any specific urinary protein diagnosis, as well as (together with CRPs) in the diagnosis of severe posttransplantation complications.

Beta2-microglobulinuria as an early sign of cytomegalovirus infection following renal transplantation.

The frequency of cytomegalovirus infection was studied in a prospective study of 106 kidney recipients. The detection of cytomegalovirus-immediate-early-antigen and cytomegalovirus-immunoglobulin (IgM) antibodies in serum was used as the reference method and showed that 23.6% (25/106) of all patients were infected. In addition, four urinary proteins (IgG and transferrin as glomerular markers and alpha1-microglobulin and beta2-microglobulin as tubular markers) were quantitatively measured in 24-h urine samples from all of the patients using an immunoluminometric assay (ILMA). In all cytomegalovirus infection cases a pronounced but isolated increase of urinary beta2-microglobulin excretion was observed. In 20 of 25 infected patients, the beta2-microglobulinuria occurred 1-21 days (median 5.0) earlier than the appearance of the cytomegalovirus-immediate-early-antigen in blood. Thus, it can be seen that the quantitative measurement of beta2-microglobulin in urine is useful for the early detection of cytomegalovirus infection following renal transplantation.

Experimental studies on the nephrotoxicity of pentamidine in rats.

Renal side-effects are frequently observed after parenteral administration of pentamidine. In this study in a rat model, the nephrotoxicity was assessed by measuring urinary loss of tubular cells, malate dehydrogenase activity and creatinine clearance. In addition, we studied the influence of other nephrotoxins such as tobramycin, amphotericin B and cyclosporin on the pentamidine-associated nephrotoxicity and proved the possibilities of reducing this toxicity by coadministration with other drugs. The tubular toxicity of pentamidine (1, 10 or 20 mg/kg daily) is dose-related and reversible. The toxicity can be reduced by coadministration of fosfomycin (1 x 500 or 2 x 250 mg/kg daily) and D-glucaro-1,5-lactam (2 x 5 mg/kg daily) and enhanced by tobramycin (2 x 2.5 mg/kg daily), amphotericin B (1 mg/kg daily) and cyclosporin (10 mg/kg daily). Furthermore, an increase in the creatinine clearance in pentamidine-treated rats can be obtained with both verapamil (2 x 1.5 mg/kg daily) and enalapril (5 mg/kg daily).

Glomerular proteinuria as an early sign of renal-transplant rejection.

The introduction of cyclosporin gave rise to an additional problem in the surveillance of renal transplant patients, namely the differentiation between cyclosporin toxicity and acute transplant rejection. The development of assays for specific proteins in urine has produced a non-invasive solution to this problem. In 55 renal transplant patients the following proteins were determined daily in 24 h-urine samples: IgG, transferrin (TF), albumin, beta 2-microglobulin (beta 2-MG), retinol binding protein (RBP), alpha 1-microglobulin (alpha 1-MG) and alpha 1-antitrypsin (alpha 1-AT). All proteins were determined quantitatively using immunoluminometric assays and 10 microliters urine in dilutions from 1:1-1:100. The urinary protein excretion was related to the actual creatinine clearance as this index gave the best differentiation between normal and abnormal status. In 24 h-urine, intraindividual peaks of IgG, TF and albumin were seen regularly in acute rejection episodes. However, a peak in the "tubular" proteins (RBP, beta 2-MG, alpha 1-MG) could not be detected. After effective treatment of the rejection episode, the renal function improved and the protein excretion returned to prerejection episode levels. In bacterial infection of the urogenital tract, urinary alpha1-AT levels rose. They returned to normal after successful antibiotic treatment. In two cases of cyclosporin toxicity neither glomerular nor tubular proteins were excreted in abnormal amounts when compared with transplant patients without complications, the only changes being an increase in serum creatinine as a result of reduced renal function.

[Beta 2-microglobulinuria in cytomegalovirus infections following kidney transplantation]. / Beta 2-Mikroglobulinurie bei Cytomegalievirus-Infektionen nach Nierentransplantation.

In a prospective study the occurrence of cytomegalovirus (CMV) infection was diagnosed by demonstrating CMV-immediate early antigen (IEA) in the blood in 13 out of 68 (19%) patients who had undergone renal transplantation (27 women, 41 men, mean age 46.3 [21-64] years). Twenty-four hour urine samples were collected at the same time for quantitative determination of selected marker proteins by immunoluminometric assays (IgG and transferrin as glomerular markers, alpha 1-microglobulin and beta 2-microglobulin as tubular markers). In all 13 confirmed cases of CMV infection there was an isolated rise in urinary beta 2-microglobulin excretion amounting to more than three times the normal. In 11 of the 13 cases the beta 2-microglobulinuria was noted before the CMV-IEA test became positive. This suggests that quantitative assay of beta 2-microglobulin in the urine may be of value in the early diagnosis of CMV infection--a matter of some prognostic importance--and may hence offer additional support for therapeutic decisions.