Tigecycline in febrile neutropenic patients with haematological malignancies: a retrospective case documentation in four university hospitals.

OBJECTIVES: Tigecycline (TGC) is a first-in-class glycylcycline with an expanded spectrum of activity. Although TGC has not been prospectively studied in febrile neutropenia (FN), we observed that occasionally critically ill neutropenic patients unresponsive to other antibiotics were treated with TGC in our departments. The aim of our study was to analyse effectiveness and toxicity of TGC in FN. METHODS: Data of infectious episodes treated with TGC were retrospectively collected. Baseline data of patients, haematological malignancy, infection and adverse events were documented. Success was defined as defervescence (≥7 days) in the absence of any sign of persistent infection. RESULTS: Data of 35 patients with haematological malignancies and FN were evaluated. Median duration of neutropenia was 25 days (range 6-69 days). The type of infection was pneumonia in 24 patients, four microbiologically documented infections, three clinically documented infections and four with fever of unknown origin. The TGC was administered after a median of two (range 1-5) prior antibiotic regimens. Treatment was successful in 15 (43 %) patients. In patients with prolonged neutropenia (≥28 days), response was significantly lower (13 vs. 79 %; p =0.001). Eight (23 %) patients died during the fever episode. Grade 3-4 toxicity occurred in five (14 %) patients. CONCLUSION: Our results showed promising response rates to TGC and very low toxicity rates compared to the generally low response rate of third-line antibiotic therapies, indicating that TGC may be a successful alternative for salvage treatment of febrile neutropenia, but further study is needed.

Physiological typing of Pseudallescheria and Scedosporium strains using Taxa Profile, a semi-automated, 384-well microtitre system.

During the last few decades, Pseudallescheria and Scedosporium infections in humans are noted with increasing frequency. Multi-drug resistance commonly occurring in this species complex interferes with adequate therapy. Rapid and correct identification of clinical isolates is of paramount significance for optimal treatment in the early stages of infection, while strain typing is necessary for epidemiological purposes. In view of the development of physiological diagnostic parameters, 570 physiological reactions were evaluated using the Taxa Profile Micronaut system, a semi-automatic, computer-assisted, 384-well microtitre platform. Thirty two strains of the Pseudallescheria and Scedosporium complex were analysed after molecular verification of correct species attribution. Of the compounds tested, 254 proved to be polymorphic. Cluster analysis was performed with the Micronaut profile software, which is linked to the ntsypc® program. The systemic opportunist S. prolificans was unambiguously separated from the remaining species. Within the P. boydii/P. apiosperma complex differentiation was noted at the level of individual strains, but no unambiguous parameters for species recognition were revealed.

Detection of hyphomycetes in the upper respiratory tract of patients with cystic fibrosis.

The respiratory tract of cystic fibrosis patients is colonised by bacteria and fungi. Although colonisation by slow growing fungi such as Pseudallescheria, Scedosporium and Exophiala species has been studied previously, the colonisation rate differs from study to study. Infections caused by these fungi have been recognised, especially after lung transplants. Monitoring of respiratory tract colonisation in cystic fibrosis patients includes the use of several semi-selective culture media to detect bacteria such as Pseudomonas aeruginosa and Burkholderia cepacia as well as Candida albicans. It is relevant to study whether conventional methods are sufficient for the detection of slow growing hyphomycetes or if additional semi-selective culture media should be used. In total, 589 respiratory specimens from cystic fibrosis patients were examined for the presence of slow growing hyphomycetes. For 439 samples from 81 patients, in addition to conventional methods, erythritol-chloramphenicol agar was used for the selective isolation of Exophiala dermatitidis and paraffin-covered liquid Sabouraud media for the detection of phaeohyphomycetes. For 150 subsequent samples from 42 patients, SceSel+ agar was used for selective isolation of Pseudallescheria and Scedosporium species,and brain-heart infusion bouillon containing a wooden stick for hyphomycete detection. Selective isolation techniques were superior in detecting non-Aspergillus hyphomycetes compared with conventional methods. Although liquid media detected fewer strains of Exophiala, Pseudallescheria and Scedosporium species, additional hyphomycete species not detected by other methods were isolated. Current conventional methods are insufficient to detect non-Aspergillus hyphomycetes, especially Exophiala, Pseudallescheria and Scedosporium species, in sputum samples of cystic fibrosis patients.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry for fast and reliable identification of clinical yeast isolates.

The clinical impact of severe infections with yeasts and yeast-like fungi has increased, especially in immunocompromised hosts. In recent years, new antifungal agents with different and partially species-specific activity patterns have become available. Therefore, rapid and reliable species identification is essential for antifungal treatment; however, conventional biochemical methods are time-consuming and require considerable expertise. We evaluated matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for the rapid routine identification of clinical yeast isolates. A total of 18 type collection strains and 267 recent clinical isolates of Candida (n = 250), Cryptococcus, Saccharomyces, Trichosporon, Geotrichum, Pichia, and Blastoschizomyces spp. were identified by MALDI-TOF MS. The results were compared with those obtained by conventional phenotyping and biochemical tests, including the API ID 32C system (bioMérieux, Nürtingen, Germany). Starting with cells from single colonies, accurate species identification by MALDI-TOF MS was achieved for 247 of the clinical isolates (92.5%). The remaining 20 isolates required complementation of the reference database with spectra for the appropriate reference strains which were obtained from type culture collections or identified by 26S rRNA gene sequencing. The absence of a suitable reference strain from the MALDI-TOF MS database was clearly indicated by log(score) values too low for the respective clinical isolates; i.e., no false-positive identifications occurred. After complementation of the database, all isolates were unambiguously identified. The established API ID 32C biochemical diagnostic system identified 244 isolates in the first round. Overall, MALDI-TOF MS proved a most rapid and reliable tool for the identification of yeasts and yeast-like fungi, with the method providing a combination of the lowest expenditure of consumables, easy interpretation of results, and a fast turnaround time.

Isolation and clinical significance of Pseudallescheria and Scedosporium species.

In the course of the past decades, Pseudallescheria/Scedosporium species have become increasingly recognized as causative agents of significant infections in humans. In our laboratory in Bonn, Germany, the first clinical strain was isolated by chance by dipping a wooden swab taken from a chronic wound process into brain-heart infusion broth. The latter was being used as an enrichment medium for the recovery of infectious agents. Subsequently, a total of 35 additional Pseudallescheria/Scedosporium strains from four patients suffering from invasive fungal infection were isolated with this method. In contrast, only 27 of the 36 isolates were detected by plating the specimens on Sabouraud glucose agar (75%). Furthermore, eight strains were recovered from the respiratory tract samples of six out of 42 patients suffering from cystic fibrosis. While all eight strains were isolated on SceSel+ agar, only five were obtained from wooden sticks dipped into broth for enrichment of infectious agents (62.5%) and only three on Sabouraud glucose agar (37.5%). The clinical cases are summarized and methods used for detection are described. Species identification is based on the taxonomy valid in 2005; in the interim several re-classifications have been proposed.

Selective isolation of Pseudallescheria and Scedosporium species from respiratory tract specimens of cystic fibrosis patients.

BACKGROUND: Fungi of the Pseudallescheria/Scedosporium complex are known to be colonizers and infectious agents of the respiratory tract of cystic fibrosis (CF) patients. Colonized CF patients are at high risk for the development of disseminated scedosporiosis after lung transplantation. The detection of these fungi may be difficult, because they grow slowly and so will be overgrown by faster-developing microorganisms on the media routinely used in diagnostic laboratories. OBJECTIVES: To examine the usefulness of the isolation medium SceSel+ agar as a diagnostic tool for clinical samples from CF patients. METHODS: 150 respiratory tract samples from 42 CF patients were inoculated on SceSel+ agar. During the incubation phase, which lasted up to 30 days at 36 +/- 1 degrees C, the cultures were inspected every 2 or 3 days. RESULTS: The isolation of Scedosporium species was successful in 3 samples (2%) with standard microbiological media and procedures, while the isolation rate on SceSel+ agar was 5.3% (8 of 150 specimens). CONCLUSIONS: Our results suggest that standard microbiological media and procedures are not sufficient to detect colonization of the respiratory tract by Pseudallescheria/Scedosporium in CF patients. By use of SceSel+ agar, fungi belonging to this complex were isolated more frequently. Therefore, this semiselective mycological isolation medium should be used for the detection of these fungi in the respiratory tract of CF patients, especially in patients in whom a fungal infection is assumed or who are scheduled for lung transplantation.

False positivity of the Aspergillus galactomannan Platelia ELISA because of piperacillin/tazobactam treatment: does it represent a clinical problem?

OBJECTIVES: False-positive results of the galactomannan (GM) ELISA caused by concurrent administration of piperacillin/tazobactam have been reported in patients with febrile neutropenia. PATIENTS AND METHODS: This prospective study investigated different sampling times in 30 patients receiving piperacillin/tazobactam for febrile neutropenia. RESULTS: Prior to the first piperacillin/tazobactam infusion, a median GM index of 0.2 [interquartile range (IQR) 0.1-0.3] was noted; in two patients (7%) the index was 0.5. Immediately after piperacillin/tazobactam infusion, the median index increased to 0.3 (IQR 0.2-0.4, P = 0.002) leading to 21% (7/30) false-positive results, if > or = 0.5 is assumed as the cut-off level. GM indices before the next piperacillin/tazobactam infusion were not increased (median 0.2, IQR 0.2-0.35, P > 0.05), but 10% (3/30) were still > or = 0.5. With a cut-off level of > 0.7, no false-positive results were noted at any sampling time point. CONCLUSIONS: We conclude that the clinical relevance of false-positive GM results during piperacillin/tazobactam treatment is small if samples are collected prior to infusion and if a cut-off level of > 0.7 is used.

An audit of efficacy and toxicity of teicoplanin versus vancomycin in febrile neutropenia: is the different toxicity profile clinically relevant?

BACKGROUND: Glycopeptides are often used for persistent fever in neutropenic patients. This study compares efficacy and toxicity of teicoplanin and vancomycin. PATIENTS AND METHODS: Hundred consecutive neutropenic patients with hematological malignancies and persistent fever after 72 h of first-line antibiotic therapy (91% piperacillin/tazobactam) were treated with teicoplanin (800 mg on day 1, then 400 mg/day)+piperacillin/tazobactam+gentamicin from 08/96 to 09/00 (group T) or with vancomycin (2 g/day)+meropenem+levofloxacin from 10/00 to 04/02 (group V). Success was defervescence (>or=7 days) in absence of any sign of continuing infection. Nephrotoxicity was monitored daily as increase in serum creatinine. RESULTS: Fifty patients were analyzed in each group. Efficacy was evaluated in patients with piperacillin/tazobactam as first-line therapy only. Treatment was successful in 76% in group T (n=42) and 59% in group V (n=49), p=0.118. Toxicity was evaluated in all patients. The median increase of creatinine was 11% (interquartile range 0%-30%) in group T and 17% (0%-74%) in group V, p=0.062. In patients who received concomitant amphotericin B (given for 7 days and 6 days, respectively, p=0.525), median creatinine increased from 0.9 mg/dl (0.8-1.1) to 1.2 mg/dl (0.9-1.5) in group T and from 0.9 mg/dl (0.8-1.08) to 1.55 mg/dl (1.33-2.23) in group V (p<0.001). This led to a doubling of creatinine in 2/23 (9%) patients of group T and in 9/16 (56%) patients of group V (p=0.003). A multivariate analysis revealed that concomitant use of amphotericin B (p<0.001) and treatment with vancomycin (p=0.002) were independently associated with nephrotoxicity. CONCLUSION: Teicoplanin and vancomycin were comparably effective in patients with neutropenia and persistent fever, but - if combined with amphotericin B - vancomycin was significantly more nephrotoxic than teicoplanin.

[Bacterial infections in pediatric cancer patients]. / Therapie bakterieller Infektionen in der pädiatrischen Onkologie.

Increased dose intensity and a better long term survival can not be reached in pediatric oncology without the judicious use of antibiotics. During periods with profound neutropenia and between intensive chemotherapy cycles are bacterial infections capable of disturbing the patients' quality of life; they may cause an acute life threatening situation and lead to a substantial increase in expenditures and consumption of ressources in supportive care. The non-judicious use of antibacterials may face the patient to an increased risk of adverse events and fosters the selection of resistant bacteria. This article provides the recommendations of the Infectious Diseases Working Party of the German Society for Pediatric Infectious Diseases (DGPI) and the German Society for Pediatric Hematology/Oncology (GPOH) for antibacterial therapy in pediatric oncology patients based upon the available literature and the clinical experience of the authors.

Wound infection due to Absidia corymbifera and Candida albicans with fatal outcome.

A case of a mixed infection due to Candida albicans and the zygomycete Absidia corymbifera in a 38-year-old, previously healthy, Caucasian male is presented. The infection developed following serial rib fractures, and ruptures of kidney, liver and biliary tract as well as a pancreatic contusion resulting from a traffic accident. During intensive care treatment the patient underwent several surgical procedures but subsequently experienced multi-organ failure and sepsis. Some weeks later, fungal growth was observed macroscopically on the patient's skin and wounds. From wound swabs C. albicans and A. corymbifera were grown. Histopathology of abdominal tissue yielded pseudohyphae and coenocytic hyphae. Although surgical debridement and antifungal treatment with amphotericin B and 5-flucytosine were started immediately, the patient died in therapy-refractory septic multi-organ failure.

Markers of bacteremia in febrile neutropenic patients with hematological malignancies: procalcitonin and IL-6 are more reliable than C-reactive protein.

Since neutropenic patients with hematological malignancies are at high risk of contracting life-threatening infections, specific markers of infection are needed in cases of febrile neutropenia. The study presented here assessed serum concentrations of C-reactive protein (CRP), procalcitonin (PCT) and interleukin-6 (IL-6) in samples obtained from 31 febrile neutropenic patients. A total of 53 episodes were evaluated, and 18 of these were associated with positive blood culture results. Procalcitonin and IL-6 concentrations differed significantly between bacteremic and non-bacteremic episodes. Procalcitonin values were 0.22 ng/ml [interquartile range (IR), 0.15-1.9] for patients with pneumonia without bacteremia, 0.22 ng/ml (IR, 0.16-0.55) for patients with fever of unknown origin, 0.2 ng/ml (IR, 0.13-0.57) for patients with non-microbial fever and 1.8 ng/ml (IR, 0.35-5.3) for patients with bacteremia. The differences between bacteremic and non-bacteremic episodes had a P-value of 0.003 using the Mann-Whitney test. For IL-6 the median values were 301 pg/ml (IR, 152-1,879) for patients with pneumonia without bacteremia, 207 pg/ml (IR, 94-445) for patients with fever of unknown origin, 177 pg/ml (IR, 142-208) for patients with non-microbial fever and 942 pg/ml (IR, 181-2,807) for patients with bacteremia. Using the Mann-Whitney test, the differences between bacteremic and non-bacteremic episodes were P=0.006. No differences were found in CRP concentrations. Cutoff levels to distinguish between bacteremic and non-bacteremic episodes were chosen using receiver operating characteristic curves: 0.62 ng/ml for PCT and 297 pg/ml for IL-6. Negative predictive values were 84% for PCT and 70% for IL-6. The results indicate that PCT and IL-6 are more reliable markers than CRP for predicting bacteremia in patients with febrile neutropenia.

Fatal pulmonary scedosporiosis.

We report on a case of scedosporiosis in a 72-year-old German woman. Her disease started with a purulent ulceration of unknown course at her left foot. Soon after onset of oral antibacterial therapy she needed in-hospital treatment because of an acute pneumonia. The infection progressed despite the application of different antibiotics. Microscopic examination of tracheal fluid revealed fungal hyphae and therefore treatment with itraconazole was initiated. However, the patient developed renal failure, required mechanical ventilation and finally died in treatment-resistant septic shock. Post-mortem Scedosporium apiospermum was cultured from lung tissue taken during autopsy. This is the fourth case of human infection caused by Scedosporium species diagnosed in our laboratory during the last 4 years.

Piperacillin-tazobactam is more effective than ceftriaxone plus gentamicin in febrile neutropenic patients with hematological malignancies: a randomized comparison.

GOALS: Efficacy and costs of empirical antibacterial therapy in febrile neutropenic patients are important issues. Several strategies have been reported to be similarly effective: monotherapy with cefepime, ceftazidime or a carbapenem or duotherapy with an antipseudomonal beta-lactam antibiotic or ceftriaxone in combination with an aminoglycoside. Piperacillin-tazobactam monotherapy is promising, but its role in this setting still has to be defined. PATIENTS AND METHODS: Of 212 consecutive febrile episodes in 130 neutropenic patients with hematological malignancies randomized to receive either piperacillin-tazobactam (4.5 g every 8 h; group A) or ceftriaxone (2 g once daily plus gentamicin 5 mg/kg once daily; group B), 183 episodes (98 group A, 85 group B) were evaluable for response. RESULTS: Defervescence within 72 h without modification of the antibiotic therapy was achieved in 56/98 episodes (57.1%) in group A and in 30/85 (35.3%) in group B (P=0.0047). If fever persisted, teicoplanin plus gentamicin (group A) or teicoplanin plus ciprofloxacin (group B) were added. All patients still febrile then received meropenem, teicoplanin and amphotericin B. With these modifications of antibiotic therapy, 89.8% of patients in group A had responded at 21 days but only 71.8% in group B (P=0.005). The mean total antibiotic drug cost in group A was only 39.4% of that in group B (euro 445 versus euro 1129; P=0.010). CONCLUSION: Piperacillin-tazobactam monotherapy is significantly more effective and cost-efficient than ceftriaxone plus gentamicin as first-line therapy in febrile neutropenic patients with hematological malignancies.

Mycetoma due to Pseudallescheria boydii and co-isolation of Nocardia abscessus in a patient injured in road accident.

We report the case of a patient who developed a mycetoma after experiencing a road accident. From surgical biopsies Pseudallescheria boydii was isolated. Subsequently, after the infection had been treated with itraconazole, a Gram-positive bacterium, identified as the newly described species Nocardia abscessus, was cultured from wound fluids.

Case Report. Maxillary sinus infection due to Emericella nidulans.

Fungal infections of the maxillary sinus are frequently caused by Aspergillus species, particularly A. fumigatus. In otherwise healthy persons there is an association with overfilling of dental root canals, when zinc-containing filling materials were used. Below, a maxillary sinus aspergilloma is reported in a young immunocompetent female patient caused by Aspergillus (Emericella) nidulans.

Pseudomonas aeruginosa outbreak in a haematology-oncology unit associated with contaminated surface cleaning equipment.

An outbreak of six cases of hospital-acquired Pseudomonas aeruginosa infections (two pneumonia two septicaemia, two skin/wound infection) occurred between August and September 2000 in an adult haematology-oncology unit at a tertiary-care centre. During the outbreak, hospital-acquired infection (HAI) incidence density rates rose from 29.4 to 62.3 (P < 0.05) infections per 1000 days at risk (i.e., neutropenic days). A systematic outbreak management system was actioned in accordance with a German draft guideline. Multiple samples from the patients' environment were tested for the presence of P. aeruginosa. A total of 4.5% of samples from sanitary equipment and 20.0% of samples from surface cleaning equipment were found to be contaminated with P. aeruginosa. Genotypic analysis by pulsed-field gel electrophoresis showed different patterns for all (N = 6) of the patient isolates, however, two of the patient isolates were identical in comparison with environmental isolates from cleaning equipment (four samples) and sanitary equipment (one sample). Our investigation revealed that the cleaning staff had used cleaning solution instead of disinfectants for decontamination of the patients' environment. The outbreak was terminated after re-adoption of surface disinfection, application of sterile filters on taps and shower heads, chemical disinfection of the washbasin drains, and appointment of a hospital hygiene nurse to a previously unfilled position. After institution of the control measures, HAI incidence densities decreased to pre-outbreak level. This investigation emphasizes the need to carefully evaluate cleaning and disinfection practices for patient care, particularly in neutropenic patients.

Low frequency of enteric infections by Salmonella, Shigella, Yersinia and Campylobacter in patients with acute leukemia.

BACKGROUND: Several authors found that isolation of Salmonella, Shigella, Yersinia and Campylobacter spp. (SSYC) from stool cultures after the 3rd day of hospitalization is a rare event. The significance of enteric infections caused by these pathogens has not been systematically investigated in severely immunosuppressed patients with acute leukemia. PATIENTS AND METHODS: We screened all patients treated on the leukemia ward of a university medical center. A total of 1,185 stool cultures from 371 episodes of diarrhea, mostly following myelosuppressive chemotherapy, were examined for the complete range of classic bacterial enteric pathogens (i.e. SSYC). RESULTS: Only three (0.25%) cultures from one patient were positive for Salmonella enteritidis. This patient suffered from cholangitis. S. enteritidis could also be detected by liver biopsy. Other infections by classic enteric pathogens were not observed. CONCLUSION: Symptomatic infections by classic bacterial enteric pathogens in hospitalized patients with acute leukemia are very rare. Stool cultures for these pathogens cannot be recommended as a routine test in uncomplicated diarrhea occurring after the 3rd hospital day.

Severe abdominal infections in neutropenic patients.

Abdominal infections are an important cause of morbidity and mortality in neutropenic patients. We present a retrospective series of 16 patients, mostly with acute leukemia, who developed severe abdominal infections during chemotherapy-induced neutropenia between 1991 and 1997. The frequency among patients with acute leukemia was 2.35% (13 of 553). Thirteen patients presented with enterocolitis and 3 patients presented with cholecystitis. Eight patients died. Bacteremia was present in 6 patients, 4 patients suffered from proven or strongly suspected fungal infections, and 1 patient suffered from cytomegalovirus infection. Early surgical management was required in a patient with intestinal obstruction, whereas other patients could be managed conservatively. Two patients with acute cholecystitis were treated with antibiotics until the end of neutropenia and then were resected. Severe abdominal injections in neutropenic patients, which are often fatal, were caused by nonbacterial microorganisms in one-fourth of the cases and could be managed conservatively in most instances.

[Antimicrobial prophylaxis of bacterial infections in pediatric oncology patients]. / Chemoprophylaxe bakterieller Infektionskrankheiten in der pädiatrischen Onkologie.

Bacterial infections are still a major challenge in the treatment of pediatric cancer patients. Considering the evidence in the literature and published consensus opinions of experts the following strategies of antibacterial chemoprophylaxis (ABCP) in pediatric cancer patients can be recommended (or not recommended): Accompanying the implantation of a ventriculoperitoneal shunt (or a Rickham-reservoir) ABCP is recommended, until prospective controlled studies including pediatric cancer patients have investigated this issue. In bone marrow or stem cell transplant recipients, the prophylactic administration of penicillin should be considered, if severe oral mucositis is a common adverse event in cancer departments with high rates of penicillin-susceptible strains of Streptococcus viridans. Prospective surveillance of resistant bacterial pathogens should be an indispensable tool of quality control in pediatric oncology departments. The risk of infection with antimicrobial-resistant isolates should be balanced against the real benefit of antimicrobial prophylaxis in every instance. ABCP should neither be given during implantation nor during prolonged usage to prevent bacterial infection of a central venous access device (unproven efficacy and potential hazards of Vancomycin-resistant gram-positive infections). The oral administration of non-absorbable ABCP or Trimetoprim-Sufomethoxazole is not recommended for the prevention of bacterial infections (unproven efficacy) and no recommendation can be given for the oral ABCP with chinolones (lacking data, risk of antimicrobial resistance).

Clostridium difficile infection in patients with neutropenia.

Clostridium difficile is the most important cause of nosocomial infectious diarrhea. The importance of C. difficile-associated diarrhea (CDAD) has been poorly investigated in patients with neutropenia who have hematologic malignancies. A retrospective chart review of all patients treated in the leukemia ward of a university medical center during 1991-2000 determined that 875 courses of myelosuppressive chemotherapy were administered. CDAD occurred in 7.0% of all cycles. In 8.2% of the patients, severe enterocolitis developed. Two patients died while they had diarrhea. However, in no patient was C. difficile infection clinically considered to be the primary cause of death. The response rate to oral metronidazole was 90.9%. These data indicate that C. difficile infection is not rare and should be suspected whenever a hospitalized patient with neutropenia develops diarrhea. Oral metronidazole can be recommended as initial drug of choice for treatment of patients with neutropenia who have hematologic malignancies and CDAD.