Paecilomyces variotii central nervous system infection in a patient with cancer

Paecilomyces variotii was isolated from two subsequent cerebrospinal fluid (CSF) specimens of a cancer patient. Identification was confirmed through beta-tubulin and rDNA ITS sequencing. MICs were determined for seven antifungal agents; the isolate was found to be susceptible to amphotericin B (AMB), itraconazole (ITZ), ketaconazole (KTZ) and 5-fluorocytosine (5FC) but resistant to fluconazole (FLZ) and miconazole (MCZ). Despite antimycotic therapy, the infection proved to be fatal.

Host-parasite relation in invasive aspergillosis

Invasive aspergillosis has become one of the most important infectious complications of intensive modern medicine often limiting the success of oncological treatments and transplantation. The rationale for this is found in the effects of immunosuppressive therapies and to a lesser degree underlying disease processes as well as in properties of the fungus. The double pronged nature of host defenses directed against spores and hyphae of Aspergilli is affected by glucocorticoids and myeloablative therapy. Resident alveolar macrophages are the major players eliminating inhaled conidia. Neutrophils, efficiently killing hyphae. These defense mechanisms are so solid that even after the inhalation of billions of spores infection is reliably prevented in man. Mechanisms by which glucocorticoids prevent macrophages from first inhibiting germination of ingested conidia and then killing them have not been elucidated. Mobilization of neutrophils is also hampered by glucocorticoids that have the potential to suppress the expression of an array of neutrophil chemokines by macrophages. Glucocorticoids are thus able to abrogate defenses against Aspergilli on their own, affecting both lines of defense. In neutrophil granulocytes oxidative killing systems directed against hyphae are of major importance as pointed out by infections in children with chronic granulomatous disease, but other killing systems such as defensins and possibly thrombocidins are also of importance. To date it remains speculative that platelet derived thrombocidins play an important role, but such speculations are tempting in view of the angio-invasive nature of the fungus and the coexisting thrombocytopenia in many patients with aspergillosis.

Immune states in long-term space flights

Maintenance of health, as contrasted to illness induced by infectious agents, reflects a tenuous balance between the host's resistance and the number and genetic characteristics of the infectious organisms present. Nature has evolved both nonspecific defense mechanisms and specific immune systems to protect the body against invasion by exogenous organisms or the numerous agents which may reside dormant within the host. Long-term space flights with their accompanying prolonged weightlessness, unaccustomed environmental factors, emotional disturbances, and unforeseen influences may alter the host's natural or specific immune states. The non-specific and specific host defenses will be discussed, and the particular effects which their alteration might have on provocation of latent viral infections will be considered. Viruses which classically may be induced to cause recurrent infections such as herpes simplex and herpes zoster will be described, but in addition the effect that altered host defenses might have on slow virus infections such as kuru and virus-induced malignancies will be emphasized.

Thiol compounds from a free-living pathogenic opportunistic amoeba, Acanthamoeba polyphaga

New bimane-reacting compounds from perchloric acid extracts have been detected by HPLC from Acanthamoeba polyphaga. The main compounds detected are cysteine, glutathione and other novel thiol compounds. All of these compounds must be thiols, since they disappear or decrease substantially when treated by N -ethylmaleimide prior to acetonitrile/bimane derivatization. Cysteine and glutathione increase in quantity when dithiothreitol reduction is applied to the fresh extract. This means that they are likely to be present in their oxidized and reduced form and indicates the possible presence of a corresponding thiol/disulphide enzymic system. There are other compounds that have a different behaviour, since although they can react with bimane, they do not disappear if treated previously by N -ethylmaleimide. This shows that they are not thiols but can react with bimane. The main thiol compounds found to be present, in both the parasite and the host lymphocyte cells, were cysteine and glutathione. We were unable to detect ovothiol A in Acanthamoeba but instead we found another thiol compound that could be structurally related to trypanothione. The new thiol compounds unique to this parasite and not present in lymphocytes will permit the study of disulphide-reducing enzymes as potential drug targets.

Immune reconstitution after haematopoietic transplantation with two different doses of pre-graft antithymocyte globulin

Antithymocyte globulin is widely used before haematopoietic transplantation with HLA-matched unrelated donors or mismatched relatives to prevent rejection and graft-versus-host disease (GVHD). However, optimal dosage is still under debate. Thirty-one consecutive children, mainly with haematological malignancies, were transplanted in a single institution with such donors, selected by HLA-A -B compatibility by serology and DRB1* by DNA typing. Antithymocyte globulin (Thymoglobuline; Sangstat) was infused at days -3, -2, -1. Total dosage varied: 16 patients received a median of 7.5 mg/kg (2.5 to 10.5: low-dose group), and 15 a median of 15.5 mg/kg (14.4 to 19.4: high-dose group). Post-transplant GVHD prophylaxis consisted of cyclosporine, short-course methotrexate and steroids. CD3(+), CD4(+) and CD19(+) cell reconstitution was slower in the high-dose group. Median time to reach 100 CD4(+) cells was 8 months vs 4 months (P = 0.03). Median time to normal CD19(+) cells was 16 months vs 8 months (P = 0.01). CD16(+)CD56(+) and CD8(+) cell reconstitution was similar. Nine patients in the high-dose group and two in the low-dose group experienced life-threatening opportunistic infections (P = 0.009). Although obtained from a limited number of patients, our data suggest that a higher pre-graft dose of antithymocyte globulin may negatively influence immune reconstitution.

The meaning of microbial exposure, infection, colonisation, and disease in clinical practice

The basic lexicon of infectious diseases includes the terms exposure, infection, colonisation, and disease, which are used to describe the clinical states in which the presence of a microbe in a host is suspected or discovered. Therefore, the lexicon is used to articulate an implied association between a host and a microbe. However, since it is often difficult to use the available clinical and diagnostic tools to discriminate the different ways in which microbes can exist in a host, the lexicon is often used in an ambiguous and imprecise manner. Another factor contributing to imprecise use of the lexicon is that microbial factors are often held responsible for disease pathogenesis. This relegates the part that the host plays in microbial pathogenesis to an exception, which leads to the need for qualification and modification of the terminology of infectious diseases. Recently, we proposed the "damage-response framework" to incorporate the contributions of both the host and the microbe in microbial pathogenesis in a synthesis whereby host damage was used as the common denominator to describe the outcome of the host-microbe relation. In this article, we illustrate how the application of the damage-response framework to clinical infectious diseases can clarify and make more precise the terminology used to convey the outcome of microbial infection in clinical practice.

[A HTLV-I carrier initially treated for Pneumocystis carinii pneumonia]

A 65-year-old woman was admitted to the hospital with complaints of dyspnea on effort Chest radiography and CT revealed bilateral interstitial infiltration. Transbronchial lung biopsy specimens revealed organisms of Pneumocystis carinii. Sulfamethoxazole-trimethoprim improved the patient's radiograph and CT, and although a positive reaction was obtained for anti-HTLV-I antibody, the hematological findings and clinical symptoms did not suggest that she had an ATL. Since discharge, she has been receiving maintenance therapy at the outpatient clinic because an opportunistic infection is predictive of the development of ATL.

Alemtuzumab in previously treated chronic lymphocytic leukemia patients who also had received fludarabine

PURPOSE

This phase II pilot study determined the efficacy and safety of alemtuzumab (Campath-1H; Burroughs Wellcome, United Kingdom) in patients with chronic lymphocytic leukemia (CLL), all of whom had previously received fludarabine and other chemotherapy regimens.

PATIENTS AND METHODS

Twenty-four patients were treated with intravenous alemtuzumab at six centers in the United States. The target dose of 30 mg over 2 hours, three times weekly, was administered for up to 16 weeks. Responses were evaluated by an independent panel of experts using 1996 National Cancer Institute-sponsored Working Group criteria. Safety assessments included analysis of lymphocyte subpopulations. Antimicrobial prophylaxis was not mandatory.

RESULTS

Eight patients (33%) achieved a major response (all partial remissions), with a median time to response of 3.9 months (range, 1.6 to 5.3 months). The median duration of response was 15.4 months (range, 4.6 to >or= 38.0 months), the median time to disease progression was 19.6 months (range, 7.7 to >or= 42.0 months), and the median survival time was 35.8 months (range, 8.8 to >or= 47.1 months). Acute infusion-related events, mainly grades 1 and 2, were most common and most severe in the first week. Ten patients (eight nonresponders and two responders) experienced major infections on-study. Pneumocystis carinii pneumonia was reported in two patients on-study; neither had received prophylaxis. Median CD4+ and CD8+ counts decreased and then began to increase by the end of the study, with further recovery by 1-month follow-up. One of 53 samples obtained from 10 patients had a low titer of alemtuzumab antibodies.

CONCLUSION

Alemtuzumab has significant activity in poor-prognosis, fludarabine-treated CLL patients. However, because of a relatively high incidence of opportunistic infections accompanying profound lymphopenia, future protocols should include mandatory prophylaxis.

CD34+-enriched peripheral blood progenitor cells from unrelated donors for allografting of adult patients: high risk of graft failure, infection and relapse despite donor lymphocyte add-back

Fifty-one adults with haematological malignancies were transplanted with CD34+-selected peripheral blood progenitor cells (PBPC) from unrelated donors. The conditioning protocol contained total body irradiation (n = 17) or combinations of busulphan and other alkylating agents (n = 34). Antithymocyte globulin was infused in all patients. The median number of CD3+ T cells infused with the graft after purification with the Isolex 300 system in the first cohort of 18 patients was 2.1 x 10(5)/kg. Prophylactic donor lymphocyte infusion (DLI) containing 1 x 10(5) CD3+ T cells was performed on d 21 in the following 33 patients who had received PBPC purified by the CliniMACS system. Early graft failure occurred in 8/51 patients (16%). After a median follow-up of 31 months (range 8-60), the probability of disease-free survival (DFS) was 36% for the whole group. Reasons for death were opportunistic infections (n = 15), graft-versus-host disease (GvHD, n = 7) and relapse (n = 4). Pre-transplant factors with significant impact on DFS were cytomegalovirus status and risk category of underlying disease. The occurrence of graft failure or GvHD was associated with poor outcome. Recipients of CD34+-selected PBPC from unrelated donors are at high risk of infectious complications, relapse and graft failure which cannot be prevented by early reinfusion of unmodified donor lymphocytes.

Low transplant-related mortality after second allogeneic peripheral blood stem cell transplant with reduced-intensity conditioning in adult patients who have failed a prior autologous transplant

Standard allogeneic stem cell transplantation (SCT) has been associated with a high transplant-related mortality (TRM) in patients who have failed a prior autologous SCT (ASCT). Reduced-intensity conditioning (RIC) regimens may reduce the toxicities and TRM of traditional myeloablative transplants. We report 46 adults who received a RIC peripheral blood SCT from an HLA-identical sibling in two multicenter prospective studies. The median interval between ASCT and allograft was 16 months, and the patients were allografted due to disease progression (n = 43) and/or secondary myelodysplasia (n = 4). Conditioning regimens consisted of fludarabine plus melphalan (n = 41) or busulphan (n = 5). The 100-day incidence of grade II-IV acute graft-versus-host disease (GVHD) was 42% (24% grade III-IV), and 10/30 evaluable patients developed chronic extensive GVHD. Early complete donor chimerism in bone marrow and peripheral blood was observed in 35/42 (83%) patients, and 16 evaluable patients had complete chimerism 1 year post transplant. With a median follow-up of 358 days (450 in 29 survivors), the 1-year incidence of TRM was 24%, and the 1-year overall (OS) and progression-free survival were 63% and 57%, respectively. Patients who had chemorefractory/ progressive disease, a low performance status or received GVHD prophylaxis with cyclosporine A alone (n = 32) had a 1-year TRM of 35% and an OS of 46%, while patients who had none of these characteristics (n = 32) had a 1-year TRM of 35% and an OS of 46% while patients who had none of these characteristics (n = 14) had a TRM of 0% and an OS of 100%. Our results suggest that adult patients who fail a prior ASCT can be salvaged with a RIC allogeneic PBSCT with a low risk of TRM, although patient selection has a profound influence on early outcome.

Listeriosis in recipients of allogeneic blood and marrow transplantation: thirteen year review of disease characteristics, treatment outcomes and a new association with human cytomegalovirus infection

Listeriosis is uncommon in recipients of allogeneic blood, marrow and organ transplantation. Six patients with systemic Listeria monocytogenes infection during 1985-1997 at Bone Marrow Transplantation Service, Memorial Sloan-Kettering Cancer Center are described. In two male and four female patients, the median duration from transplantation to isolation of L. monocytogenes was 62.5 (range 29 to 821) days. Among five allogeneic marrow transplant recipients, four (80%) received HLA antigen matched, T cell-depleted grafts from three unrelated and a single related donor. One patient underwent mismatched-related marrow graft transplant. Cord stem cell transplantation was performed in a single patient. Two required therapy for graft-versus-host disease (GVHD). The 13 year incidence of systemic Listeria infections was 0.47 percent. All six presented with fever (>39 degrees C), and L. monocytogenes bloodstream invasion. Mental status changes and meningioencephalitis were observed in two (33.3%). A concurrent primary opportunistic infection was present in five individuals (83.3%), and four (80%) were being treated for acute human cytomegalovirus (HCMV) viremia. Sixty-six percent responded to therapy and two died from unrelated, non-listeric causes. Systemic listeriosis was uncommon in our high-risk allogeneic blood and marrow transplantation population, and response to therapy with parenteral ampicillin and gentamicin was excellent. The association between primary HCMV reactivation and subsequent listeric infection emphasizes the significance of HCMV-related dysfunction in hosts' cellular immune responses, especially in the setting of allogeneic transplantation.

[Pneumocystis carinii and cytomegalovirus pneumonia after corticosteroid therapy in acute severe alcoholic hepatitis: 2 case reports]

Most cases of infections described after steroid treatment for severe acute alcoholic hepatitis are of bacterial origin. However, the rate of bacterial infections in these patients is not higher than in those who are not treated by steroids. The opportunistic infections are even more rare. We report two cases of patients with cirrhosis and human immunodeficiency virus, treated for alcoholic hepatitis with steroids and who subsequently developed severe pneumopathy due to Pneumocystis carinii. One patient had a concommitant cytomegalovirus infection and both of them died. Pneumocystis carinii infections usually occur in patients a decreased immune cellular response. Steroid treatments and also alcohol may be responsible for these opportunistic infections. Alcohol may have an immunosuppressive effect by decreasing recruitment of CD4 and CD8 lymphocytes to the lungs. In conclusion, Pneumocystis carinii pneumonia is a potential complication of steroid treatments for acute alcoholic hepatitis and should be suspected in case of unexplained pulmonary infection.

Human herpesvirus 8 and associated diseases in a group of 67 human immunodeficiency virus-seropositive individuals

Human herpesvirus 8 (HHV-8) is involved in the pathogenesis of Kaposi's sarcoma, of B-cells lymphomas, and of Castelman's disease. However, the role of this virus is not yet well known. To investigate the relationship between HHV-8 infection and diseases correlated with human immunodeficiency virus (HIV), we studied a cohort of 67 HIV-seropositive subjects, some of them coinfected with HHV-8. An indirect immunofluorescence test was employed to detect the antibodies against this virus. Positive cases were 31 (46.3%); among the 67 patients, 14 were weakly positive, or + (20.9%); 11 were significantly positive, or ++ (16.4%); and 6 were strongly positive, or (8.9%). These last six patients were the most affected by opportunistic infections, and all were affected by neoplastic pathologies. Moreover, the HHV-8 positive subjects showed hematologic and martial alterations more severe than those in the negative subjects. HHV-8 seroprevalence in HIV-seropositive patients of our cohort was higher (46.3%) than in normal population (0-10%). The presence of disseminated Kaposi's sarcoma and other neoplasms associated with high HIV-RNA levels in HHV-8-positive patients, and particularly in those with strong positivity, corroborates the hypothesis that the virus is correlated with the progression of HIV infection and with its related diseases, especially those that are neoplastic. Last, the severe alterations of iron metabolism found in the patients coinfected with HHV-8 and the negative effect of this virus on the lymphocytic populations can contribute to the unfavorable evolution of HIV infection and also might facilitate tumor development.

Recovery of filamentous fungi from water in a paediatric bone marrow transplantation unit

In order to determine whether water or water-related surfaces are a reservoir for opportunistic filamentous fungi, water sampling in the paediatric bone marrow transplantation (BMT) unit of the National Hospital University of Oslo, Norway was performed. During a six-month period 168 water samples and 20 samples from water-related surfaces were taken. The water samples were taken from the taps and showers in the BMT unit and from the main pipe supplying the paediatric department with water. In addition, 20 water samples were taken at the intake reservoir supplying the city of Oslo with drinking water. Filamentous fungi were recovered from 94% of all the water samples taken inside the hospital with a mean colony forming unit (cfu) count of 2.7/500mL of water. Aspergillus fumigatus was recovered from 49% and 5.6% of water samples from the taps and showers, respectively (mean 1.9 and 1.0cfu/500mL). More than one third (38.8%) of water samples from the main pipe revealed A. fumigatus (mean 2.1cfu/500mL). All water samples taken at the intake reservoir were culture positive for filamentous fungi, 85% of the water samples showed A. fumigatus (mean 3.1cfu/500mL). Twenty-five percent of water-related surfaces yielded filamentous fungi, but A. fumigatus was recovered from only two samples. We showed that filamentous fungi are present in the hospital water and to a lesser extent on water-related surfaces. The recovery of filamentous fungi in water samples taken at the intake reservoir suggests that the source of contamination is located outside the hospital.