Lethal Pulmonary Hemorrhage Caused by a FulminantStenotrophomonas maltophiliaRespiratory Infection in an Acute Myeloid Leukemia Patient

Stenotrophomonas maltophilia (Sm) pneumonia in immunocompromized hosts is an increasingly common nosocomial infection. Even though resistant to multiple antimicrobials, this gram-negative bacteria usually does not present with a fulminant course leading to a fatal hemorrhagic respiratory infection in neutropenic patients. We report here the case of a 63-year-old woman treated by intensive chemotherapy for acute myeloid leukemia (AML) who presented while severely neutropenic and thrombocytopenic a Sm pulmonary infection with hemoptysis leading to death in 48 h. The bronchoalveolar lavage (BAL) performed shortly before death was highly hemorrhagic and contained a striking amount of extra- and intra-cellular pathogens. Blood and BAL cultures grew S. maltophilia. Post-mortem examination revealed bilateral extensive intra-alveolar hemorrhage (IAH) associated with a great amount of microorganisms and severe bone marrow aplasia was observed without evidence of leukemia residual disease. Sm pneumonia usually does not evolve into such a devastating clinical picture although infections due to the bacteria are known to be associated with high morbidity and mortality. So far, the present observation is the fourth similar case reported in the literature. Even though an early diagnosis and an adequate antibiotic prescription may improve Sm infection prognosis, S. maltophilia proves difficult to eradicate due to a high resistance rate in part intrinsic but also in part acquired.

Imaging findings of pulmonary infection caused by Scedosporium prolificans in a deep immunocompromised patient’

Scedosporium prolificans is an emerging fungus that causes rapid progressive and disseminated infections in immunodepressed patients. We present a case of a 34-year-old woman with chronic myelogenous leukemia who received a bone marrow transplantation and suffered a sudden respiratory failure in +67 day. Chest radiographies showed growing bilateral patchy condensations. Computed Tomography depicted bilateral nodular condensation of alveolar space. S. prolificans was detected from sputum, but the patient died 72 h later. Imaging findings of lung scedosporiosis are nonspecific, but CT may provide a prompter diagnosis and allow to add newer antifungal treatments. This report presents the first imaging report of lung scedosporiosis.

Candidemia in patients with acute leukemia

PURPOSE

To present the clinical course and laboratory results of leukemic patients with candidemia and to comment on the incidence and clinical findings of mycoses in this particular patient population.

PATIENTS AND METHODS

From 2002 to 2005 in the Department of Hematology of our institution 53 leukemic patients with clinical signs of infection and severe neutropenia after intensive chemotherapy presented 127 febrile episodes during which blood cultures were taken, both from central venous catheters and from peripheral veins with a sterile method as described elsewhere.

RESULTS

4/53 (7.5%) of neutropenic patients presented disseminated candidiasis with positive blood cultures with different species of Candida (C) according to the EORTC criteria. Two patients had strains susceptible to all or most antifungal agents, 1 had dose-dependent sensitivity and 1 had C. krusei resistant to all agents. Two patients died probably because of disseminated candidiasis, 1 survived and 1 died of unrelated cause.

CONCLUSION

Fungal infections are not uncommon in patients with hematological malignancies, but they are rarely microbiologically documented. A fast and reliable means of diagnosis of invasive fungal infections is urgently needed.

Immunological characterization and antibacterial function of persisting granulocytes in leukemic patients receiving pulse cytosine arabinoside-consolidation chemotherapy on days 1, 3, and 5

High-dose cytosine arabinoside (HiDAC) and intermediate-dose cytosine arabinoside (IDAC) have been introduced as effective and safe consolidation chemotherapy in acute myeloid leukemia, with relatively low rates of life-threatening infections despite the high total dose of the cytostatic drug. To explore the biological background of low toxicity, we examined the numbers, immunophenotype, and functional properties of granulocytes in patients with acute myeloid leukemia receiving HiDAC or IDAC. Interestingly, the absolute numbers of neutrophils remained >500/microl until day 10 in 92 of 125 (74%) HiDAC cycles and in 106 of 113 (94%) IDAC cycles. As assessed by electron microscopy, these day-10 granulocytes surviving chemotherapy were found to be mature cells containing secondary granules and phagolysosomes. They also expressed opsonization- and phagocytosis-linked surface Ags (C3biR, CR1, C1qR, C5aR, FcgammaRI, FcgammaRII, FcgammaRIII, and G-CSF and GM-CSF receptors) like neutrophils in healthy controls. Moreover, these day-10 neutrophils exhibited oxidative burst activity and took up and digested bacteria in the same way as neutrophils in healthy controls. There was a negative correlation between absolute neutrophil counts and severe infections in HiDAC- and IDAC-treated patients with a later onset of infections in IDAC patients (median: IDAC, day 18; HiDAC, day 16). Together, functionally mature neutrophils are detectable at least until day 10 in patients treated with HiDAC or IDAC, and may explain the relatively low hematologic toxicity of these consolidation protocols. IDAC is a superior protocol in this regard and may therefore be most suitable for elderly patients and those at high risk for severe infections.

Common genetic variants in the interleukin-6 and chitotriosidase genes are associated with the risk for serious infection in children undergoing therapy for acute myeloid leukemia

Infectious complications represent a substantial cause of morbidity and mortality in children undergoing therapy for acute myeloid leukemia (AML). Since it has been shown that alterations in innate immune pathways contribute to the risk for serious infections, we analyzed well-characterized variants in innate immune genes (TNF, IL6, IL8, MPO, CHIT, FCGR2A, TLR2, and TLR4) to determine their possible contribution to infectious complications during therapy for pediatric AML. The study population consisted of 168 North European Caucasian children enrolled on the clinical trial AML-BFM 93. We found an association between Gram-negative bacterial infection and common, functional variants in two genes, IL6 and CHIT. The risk for infection was significantly higher in children with the G allele in the IL6 promoter at -174 bp (P=0.026) and in patients with the H allele of CHIT (P=0.033). The promoter variant in IL6 has been shown to increase expression while the H allele disrupts both function and circulating levels. Our data suggest that variant alleles of both IL6 and CHIT could influence susceptibility to infection with Gram-negative bacteria in children undergoing therapy for AML. Follow-up studies, namely replication association studies and in vitro investigation of these common polymorphisms, are warranted to confirm these observations.

[Generalized cryptococcosis in HIV infection]

Two cases of generalized cryptococcosis in patients who died of HIV infection are described. The course of the disease was masked by other diseases and final diagnosis was established after necropsy. Leukemia was a clinical "mask" in one case and generalized tuberculosis in the other. Numerous cryptococci were found in different organs histologically with positive Shiff-reaction. Ultrastructurally, cryptococci were of variable forms this probably reflecting different stages of interaction between microorganisms and the host.

Spontaneous remission in adult acute myeloid leukemia in association with systemic bacterial infection-case report and review of the literature

Spontaneous remission of acute myeloid leukemia in the adult is a rare event. We report on a 31-year-old male patient suffering from acute myeloid leukemia (AML) M5a according to the French-American-British (FAB) classification with biphenotypic features in flow cytometric examination and severe bacterial infection with group G streptococci at the time of diagnosis. Because of sepsis and stable clinical conditions, chemotherapy was delayed and antibiotics were administered intravenously. Within 6 weeks a spontaneous remission of AML occurred. Remission lasted for about 2 months. At the time of relapse, a change in phenotype of the leukemic blasts with a loss of B-lymphoid markers could be demonstrated by flow cytometry. The patient was treated with an induction therapy according to the multicentric German AMLCG 2000 schedule. To our knowledge, this is the first report of a spontaneous remission in an AML FAB M5a associated with coexpression of myeloid- and lymphoid-associated antigens on the leukemic blasts. Possible mechanisms of this phenomenon are discussed with a review of the literature.

Isolation from blood culture of a Leclercia adecarboxylata strain producing an SHV-12 extended-spectrum beta-lactamase

We report on the first isolation of an extended-spectrum beta-lactamase-producing Leclercia adecarboxylata strain from the bloodstream in a 58-year-old man with acute myeloid leukemia. The strain, resistant to ceftazidime, cefotaxime, and aztreonam, produces the SHV-12 beta-lactamase, one of the most common variants found in Italian nosocomial isolates of Enterobacteriaceae.

[Paecilomyces lilacinus systemic infection in an immunocompromised child]

The incidence of systemic fungal infections increased during the last two decades. Rare fungi, such as Mucor, Fusarium and Paecilomyces, are emerging as causes of systemic fungal infections in immunocompromised hosts. There are reports of cutaneous infections, endophthalmitis, keratitis, sinusitis, neuropathy and fungemia in immunocompromised and immunocompetent adult patients. We report a 5 years old neutropenic patient with acute myeloid leukemia treated with multiple courses of chemotherapy, with a fungemia caused by Paecilomyces lilacinus (PL). His initial clinical course was characterized by fever, skin lesions, respiratory distress and shock. Blood and bone marrow cultures were positive. The patient was treated with amphotericin B and itraconazole with a good clinical response.

Pneumocystis carinii pneumonia in patients with malignant haematological diseases: 10 years' experience of infection in GIMEMA centres

A retrospective survey was conducted over a 10-year period (1990-99) among 52 haematology divisions in order to evaluate the clinical and laboratory characteristics and outcome of patients with proven Pneumocystis carinii pneumonia (PCP) complicating haematological diseases. The study included 55 patients (18 with non-Hodgkin's lymphoma, 10 with acute lymphoblastic leukaemia, eight with acute myeloid leukaemia, five with chronic myeloid leukaemia, four with chronic lymphocytic leukaemia, four with multiple myeloma, three with myelodysplastic syndrome, two with myelofibrosis and one with thalassemia) who developed PCP. Among these, 18 (33%) underwent stem cell transplantation; only two received an oral prophylaxis with trimethroprim/sulphamethoxazole. Twelve patients (22%) developed PCP despite protective isolation in a laminar airflow room. The most frequent symptoms were: fever (86%), dyspnoea (78%), non-productive cough (71%), thoracic pain (14%) and chills (5%); a severe hypoxaemia was present in 39 patients (71%). Chest radiography or computerized tomography showed interstitial infiltrates in 34 patients (62%), alveolar infiltrates in 12 patients (22%), and alveolar-interstitial infiltrates in nine patients (16%). Bronchoalveolar lavage was diagnostic in 47/48 patients, induced sputum in 9/18 patients and lung biopsy in 3/8 patients. The diagnosis was made in two patients at autopsy. All patients except one started a specific treatment (52 patients trimethroprim/sulphamethoxazole, one pentamidine and one dapsone). Sixteen patients (29%) died of PCP within 30 d of diagnosis. Multivariate analysis showed that prolonged steroid treatment (P < 0.006) and a radiological picture of diffuse lung involvement (P < 0.003) were negative diagnostic factors.

Prior invasive pulmonary and cerebellar mucormycosis is not a primary contraindication to perform an autologous stem cell transplatation in leukemia

Mucormycosis infections, caused by fungi of the families Rhizopus, Mucor or Absidia, are typically rapidly progressive and often fatal. We report a 27-year-old male with acute myeloid leukemia (AML) developing an invasive pulmonary-CNS mucormycosis during the neutropenic period after salvage induction chemotherapy; the infection was successfully controlled with surgery and antifungal therapy. The patient received two courses of consolidation chemotherapy and underwent autologous stem cells transplantation (ASCT) while receiving secondary antifungal systemic prophylaxis with liposomal Amphotericin B (L-AMB, Ambisome). There was no clinical, radiological or microbiological evidence of mycotic reactivation during the bone marrow transplantation (BMT) procedure.

Scedosporium endophthalmitis: two fatal disseminated cases of Scedosporium infection presenting with endophthalmitis

The incidence of disseminated infection with Scedosporium species is increasing in patients with haematological malignancy. Two fatal cases are reported of patients with acute myeloid leukaemia and neutropenia who presented with Scedosporium endophthalmitis. Diagnosis of fungal infection was delayed as blood and vitreous cultures were positive only after 3 days in patient 1 and blood culture was positive at 7 days in patient 2. Despite antifungal therapy with amphotericin B and additional fluconazole in patient 2, both patients died of overwhelming fungal septicaemia. Post-mortem examination of the right globe in patient 1 showed haemorrhagic necrotizing chorioretinitis with numerous fungal hyphae in choroidal vessels, choroid, retina and vitreous. Scedosporium species are often resistant to conventional antifungal therapy including amphotericin B. Diagnosis is difficult and mortality in disseminated infection is high.

Polyclonal proliferation of large granular lymphocytes during cytomegalovirus primary infection in a human immunodeficiency virus-infected patient receiving antiretroviral therapy

We report the first case of a patient infected with HIV in whom polyclonal CD8+/CD57- T lymphocyte large granular lymphocyte (LGL) proliferation was observed in association with cytomegalovirus primary infection. Because the differential diagnosis of an increased number of LGLs includes both monoclonal LGL leukemia and polyclonal proliferation of LGL, patients in whom LGL proliferation is detected always need close hematological and clinical observation to determine whether therapeutic intervention is necessary.

Older patients with high-risk fungal infections can be successfully allografted using non-myeloablative conditioning in combination with intensified supportive care regimens

Leukaemic patients with advanced disease and severe fungal infections as well as older patients with substantial co-morbidity are usually excluded from conventional allotransplantation because of increased morbidity and mortality. We approached allogeneic transplantation in four patients with a median age of 62 years (one chronic myeloid leukaemia in blast crisis, one high-risk acute myeloid leukaemia (AML) in first complete remission (CR1), one AML in 2nd relapse, one AML in CR2 with pre-existing fungal lung infections (two aspergillus, two mucor) and additional co-morbidity (diabetes n = 2, aortic aneurysm n = 1, arterial sclerosis n = 2) by combining non-myeloablative conditioning with an intensified supportive care regimen, including amphotericin B and 4-12 (median 9) prophylactic granulocyte transfusions from granulocyte colony-stimulating factor (G-CSF)-stimulated volunteer donors. G-CSF was also given to patients until neutrophil recovery. All four patients recovered to a neutrophil count of 0.5 x 109/l after a median of 11.5 d (range 11-13 d). Prophylactic granulocyte transfusions also reduced the need for platelet transfusions and minimized mucositis. All patients were discharged at a median of 25 d (range 18-59 d) and are alive and well after a median follow-up of > 390 d (range 336-417 d) without evidence of leukaemia. Regression of the fungal lesions was documented in three patients, with a slight progression detected by computerized tomography scan of the chest in one patient. We conclude that pulmonary fungal infections are not a contraindication for allogeneic stem cell transplantation, if non-myeloablative conditioning regimens are used in combination with granulocyte transfusions, intravenous amphotericin B and G-CSF.

Prospective screening by a panfungal polymerase chain reaction assay in patients at risk for fungal infections: implications for the management of febrile neutropenia

Invasive fungal infections are a major cause of mortality in neutropenic cancer patients. To determine whether a polymerase chain reaction (PCR)-based assay enabled the identification of patients at risk for invasive fungal infections, a prospective monitoring once per week was performed during 92 neutropenic episodes in patients receiving chemotherapy for acute leukaemia or high-dose therapy followed by allogeneic or autologous stem cell transplantation, with the investigators blinded to clinical and microbiological data. PCR positivity was documented in 34 out of 92 risk episodes. All patients developing proven invasive fungal infection were found PCR positive, and PCR was found to be the earliest indicator of invasive fungal infection preceding clinical evidence by a mean of 5.75 d (range 0-14 d). In febrile neutropenic patients without a prior history of invasive fungal infection, a sensitivity of 100% and a specificity of 73% of the PCR assay for the development of proven or probable invasive fungal infection was documented. In conclusion, panfungal PCR performed prospectively once a week enabled the identification of patients at high risk for invasive fungal infections.

The epidemiology of fusariosis in patients with haematological diseases. Gimema Infection Programme

Fusariosis has been considered an emerging infection in patients with haematological malignancies. In a multicentre retrospective study on filamentous fungi infections in patients with haematological diseases over a period of 10 years in Italy, fusariosis was documented in six patients from two of the 14 centres with a 0.06% incidence in acute leukaemia. A literature search yielded 177 cases of Fusarium infections in haematological diseases and acute leukaemia accounted for 71% of the underlying conditions. An increase from 0.5 to 3.8 cases per year was observed at the M.D. Anderson Cancer Center of Houston in the periods 1975-85 and 1986-95 respectively. Conversely, only 5.1 and 6.3 cases per year have been reported in the periods 1981-90 and 1991-96, respectively, from the other centres in the world. Half of the cases have been observed in the USA. In Europe, most of the cases have been observed in France and Italy. Invasive fusariosis is a rare complication in haematological diseases, as its overall frequency does not seem to be significantly increased within the last 20 years. However, its epidemiological distribution is not homogeneous and the possibility of local clusters of infections by this deadly pathogen should be carefully considered.

Microbiological findings in febrile neutropenia

BACKGROUND

This study was carried out to assess the isolation rate of bacterial and fungal causative agents in Mexican neutropenic adults with hematological neoplasia.

METHODS

A prospective observational survey involving 120 consecutive episodes of febrile neutropenia during 1 year was carried out. These episodes were observed in 630 patients discharged with diagnoses of leukemia or lymphoma, or after bone-marrow transplantation.

RESULTS

At least one pathogen was isolated in 42 of 120 episodes (35%), and was present in 39 patients with acute myeloid leukemia (AML) (43%), acute lymphoblastic leukemia (ALL) (23%), and in patients who underwent bone-marrow transplantation (20%). Primary bacteremia was the most frequent cause of fever (24 episodes, 57%), followed by intravascular device-related infections (5 episodes, 17%), and soft-tissue infections (5 episodes, 15%). Escherichia coli (33%) was the most frequently isolated agent of primary bacteremia, followed by coagulase-negative Staphylococcus (29%), and Klebsiella oxytoca (16%). Fungal infection was responsible for five events (4%): two episodes of pneumonia (Penicillium marneffei and Aspergillus fumigatus, one event each); two cases of fungemia, one due to Candida tropicalis and one to Rhodotorula gluttinis, and one cryptococcal meningitis event.

CONCLUSIONS

The isolation rate, approximately 30%, was in accordance with previous reports; similar percentages of Gram-positive and Gram-negative isolates were found. A remarkably low rate of viridans group streptococci and fungal agents was observed, despite the fact that neutropenia is the main risk factor for infection due to these agents. Studies reporting local microbiological findings are necessary because they support an antibiotic choice for prophylaxis or therapy more accurately than reports from other areas.

Hepatosplenic candidiasis in patients with acute leukaemia

A retrospective study of 23 patients with acute leukaemia and hepatosplenic candidiasis (HSC) was conducted to evaluate clinical treatment characteristics in terms of amount and duration of antifungal agents and to assess treatment outcome. Patients were admitted to two major tertiary care centres between 1990 and 1998. The diagnosis of HSC was based on clinical, blood cultures, histologic and imaging studies. Patients were treated with amphotericin B without interruption of the planned chemotherapy regimens. Serial magnetic resonance imaging (MRI) studies were the main tool for following patients' response and activity of the fungal lesions in conjunction with clinical and laboratory parameters. Treatment with amphotericin B was continued until resolution of all clinical symptoms and signs attributable to HSC, obtaining negative blood cultures and the appearance of at least healed lesions on MRI. Amphotericin B was discontinued in four patients because of severe nephrotoxicity (two patients), or continuous fever and persistent fungal lesions on MRI (two patients). Amphotericin B lipid complex (ABELCET) was successfully used as salvage therapy for these refractory patients. Four patients died with evidence of HSC despite treatment and supportive measures. The response rate for treatment of HSC was 82%. The mean total dose of amphotericin B including empirical treatment was 4 g and the median duration of treatment for responding patients was 112 d. The median number of days of anti- fungal treatment before the disappearance of fever was 19 d. Our results confirmed the need for protracted courses of antifungal agents for the successful eradication of HSC. Chemotherapy for the underlying disorder should not be interrupted or delayed in order to treat HSC.

Stenotrophomonas maltophilia: an increasing problem in patients with acute leukaemia

Stenotrophomonas maltophilia (previously Pseudomonas maltophilia and Xanthomonas maltophilia) is an increasing problem as an opportunistic pathogen in immunocompromised patients such as those with acute leukaemia. Infection is difficult to treat and eradicate due to its inherent and quickly acquired resistance to many antibiotics. Presentation with unusual cutaneous lesions is not uncommon and can present diagnostic difficulties. We present two cases which highlight the classical features of this infection in leukaemic patients, and discuss the need for early antibiotic treatment with regimens including cotrimoxazole, and the consideration of prompt central venous catheter removal.

Intracellular multiplication of Legionella pneumophila in HL-60 cells functionally differentiated in response to 22-oxacalcitriol

The agent 1,25-dihydroxyvitamin D3 (D3) induces the differentiation of HL-60 human leukemia cells into functional monocyte-like cells that can support the intracellular multiplication of Legionella pneumophila. 22-Oxacalcitriol (OCT), a synthetic analogue of D3, exhibits greater differentiation-inducing activity than D3 in WEHI-3 mouse leukemia cells and has been suggested to be clinically more useful because of its lower hypercalcemic activity. The abilities of OCT and D3 to induce the functional differentiation of human leukemia HL-60 cells have now been investigated. OCT induced the differentiation of HL-60 cells into monocyte-like cells to a similar extent as D3. Thus, both OCT and D3 increased (1) the surface expression of CD11b, CD11c, CD14, and CD35; (2) nonspecific esterase staining; and (3) phagocytic activity toward fluorescent beads. HL-60 cells differentiated in response to OCT also supported the intracellular multiplication of L. pneumophila. Activation of both OCT- and D3-treated HL-60 cells with human recombinant interferon-gamma (IFN-gamma) for 24 h before infection markedly inhibited L. pneumophila multiplication. IFN-gamma activation enhanced superoxide anion generation by D3-treated HL-60 cells but not by OCT-treated HL-60 cells, suggesting that the inhibition of L. pneumophila multiplication in IFN-gamma-activated cells is independent of superoxide generation. Finally, D3, but not OCT, markedly stimulated the formation of osteoclast-like multinucleated cells from mouse bone marrow cells, consistent with the lower hypercalcemic activity of OCT.

Ten-year survey of incidence of infection as a cause of death in hematologic malignancies: study of 90 autopsied cases

We investigated 90 autopsied cases with hematologic malignancy, including malignant lymphoma (ML), acute leukemia (AL), and adult T-cell leukemia (ATL) peculiar to our district, during the 10-year period 1982-1991 to determine the change in incidence of infection as a cause of death. We divided the cases into two groups representing the first half decade (1982-1986) and the second half decade (1987-1991) and compared the findings made in the two groups. Although infection was the major cause of death in those autopsied cases, the incidence of fatal infections decreased during the latter period. The incidence of fatal bacterial infections decreased, while fungal infections showed a relative increase. Pneumocystis carinii pneumonia and cytomegalovirus (CMV) infection occurred more frequently in patients with ATL than in those with ML or AL. Combined infection by more than three pathogens was observed in 2 cases of ATL. Our study revealed the characteristics of ATL specific to our district, and indicated the need to apply new strategies to prevent and treat fungal and viral infections in patients with hematologic malignancies.

Different abilities of Friend murine leukemia virus (MuLV) and Moloney MuLV to induce promonocytic leukemia are due to determinants in both psi-gag-PR and env regions

Moloney murine leukemia virus (M-MuLV) is capable of inducing promonocytic leukemia in 50% of adult BALB/c mice that have received peritoneal injections of pristane, but Friend MuLV strain 57 (F-MuLV) is nonleukemogenic under similar conditions. It was shown earlier that these differences could not be mapped to the U3 region of the virus long terminal repeat, indicating the probable influence of structural genes and/or R-U5 sequences. In this study, reciprocal chimeras containing exchanged structural genes and R-U5 sequences from these two closely related viruses were analyzed for differences in ability to induce disease. Results showed that two regions of F-MuLV, psi-gag-PR and env, when substituted for those of M-MuLV were dramatically disease attenuating. The 5'-most region, which is widely distributed, overlaps with the 5' end of the env intron and includes the RNA packaging region, psi, the entire gag coding region, and the viral protease coding region (PR) of pol. It was also found that reciprocal constructs having substitutions of both of these regions of M-MuLV in an F-MuLV background allowed full reestablishment of promonocytic leukemia. These leukemias were positive for c-myb rearrangements which are characteristic of M-MuLV-induced promonocytic leukemias. Neither region alone, however, was sufficient to produce disease with a greater incidence than 13%. Further studies demonstrated that the inability of viruses with psi, gag, PR, or env sequences from F-MuLV to induce leukemia in this model system was not due to their inability to replicate in hematopoietic tissue, to integrate into the c-myb locus early on after infection in vivo, or to express gag-myb mRNA characteristic of M-MuLV-induced preleukemic cells and acute leukemia.

Hepatosplenic yeast infection in patients with acute leukemia: a diagnostic problem

The occurrence of hepatosplenic candidiasis following prolonged neutropenic periods has emerged as a major problem for patients with leukemia. In order to evaluate the diagnostic value of various available procedures, we analyzed our findings regarding 26 leukemic patients with hepatosplenic candidiasis. A significantly increased level (> 50 mg/L) of serum C-reactive protein (S-CRP) was significantly more common than a daily fever (for which the mean temperature peak was > 37.5 degrees C) or raised levels of liver enzymes (serum alanine transferase, aspartate transferase, or alkaline phosphatase). Focal changes in the liver, spleen, or kidneys were detected in > 90% of the patients examined by computed tomography (CT) but in < 50% of those examined by ultrasonography. Seventeen diagnoses were based on the findings from microscopy of samples obtained invasively, whereas a positive fungal culture was the basis of the diagnosis for only five patients. In conclusion, monitoring the S-CRP level after a patient's recovery from neutropenia is useful in that its elevation is cause for early suspicion of hepatosplenic candidiasis. In detection of the hepatosplenic foci, CT is superior to ultrasonography. For establishing the specific diagnosis, aggressive collection of samples for microscopy is essential.

Graffi murine leukemia virus: molecular cloning and characterization of the myeloid leukemia-inducing agent

The Graffi murine leukemia virus (MuLV) is a retroviral mixture that induces predominantly myeloid leukemia in several inbred strains of mice. To analyze the viral component responsible for the myeloid leukemogenesis, we cloned several proviruses from a Graffi MuLV-infected cell line. Several infectious molecular clones were obtained that could be classified into two distinct groups of infectious MuLV. Both types of MuLV were nondefective, ecotropic, and NB tropic and induced granulocytic leukemia in BALB/c and NFS mice. Restriction enzyme analysis and molecular hybridization with several MuLV probes on one molecular clone from each group revealed that both groups are closely related to each other but are clearly distinct from all known retroviruses. One component of MuLV, however, induced leukemia with a shorter latency period and harbored a lengthier long terminal repeat. The long terminal repeat of the more leukemogenic component of MuLV had acquired a 60-bp perfect duplication in the U3 region. Analysis of the tumor DNAs with probes for the mouse T-cell receptor and immunoglobulin heavy chain genes revealed frequent rearrangements with one or both probes. This concomitant expression by leukemic cells of markers of different lineages, observed in human leukemias, has been termed "lineage infidelity" and confirms that the latter rearrangements are not restricted to hematopoietic precursors committed to lymphoid differentiation.

Infection of a leukemic cell line (K562) by hepatitis B virus induces cell growth inhibition

Hepatitis B virus inhibits the in vitro growth of the human leukemic cell line K562; however, the mechanism of this growth inhibition is not understood. One to 12 days after exposure, viral DNA and RNA were detected in K562 cells by Southern blot and reverse-transcriptase polymerase chain reaction analyses. Virus-containing serum that was heat-inactivated failed to inhibit cell growth and no viral DNA or RNA was detected in these cells. In addition, murine monoclonal antibodies directed to hepatitis B virus surface epitopes neutralized the virus-induced growth inhibition whereas antibodies to hepatitis B virus core epitopes failed to suppress the inhibition. These results indicate that in vitro infection of K562 cells by hepatitis B virus causes inhibition of hematopoietic cell line growth.

Epstein-Barr viral DNA in acute large granular lymphocyte (natural killer) leukemic cells

Serologic studies in a male Caucasian presenting with an acute hepatitis-like illness, associated with an increase in peripheral blood large granular lymphocytes (LGLs), suggested a chronic or reactived Epstein-Barr virus (EBV) infection. The LGL were shown to have a natural killer (NK) cell, CD3- CD16- CD56+ CD57- phenotype and mediated strong nonspecific major histocompatability complex-unrestricted (NK) cytotoxic activity. A progressive increase in the peripheral blood LGL count was associated with a rapid deterioration, hepatic necrosis, and death. Widespread organ infiltration with LGLs suggested a malignant lymphoproliferative condition, but no lymphoid (T-cell receptor or IgH) gene rearrangement or cytogenetic marker was detected. However, molecular analysis identified EBV genomic DNA present in a single episomal form within the LGL, establishing the clonal nature of the LGL proliferation. Confirmation that the EBV had infected the leukemic LGL was obtained by in situ hybridization studies that showed EBV RNA within the LGLs. Immunoblotting of LGL protein extracts established that, of the EBV gene products, EBV nuclear antigen-1 (EBNA-1) was expressed but EBNA-2 and the latent membrane protein (LMP-1) were not detectable in the leukemic cells. These results suggest that EBV may be involved directly in LGL cell transformation, in a manner similar to EBV-associated B-cell lymphomas, although other molecular changes probably contribute to the evolution of a fully malignant leukemic clone.

Hematopoietic reconstitution after high-dose chemotherapy and autologous nonfrozen bone marrow rescue

The kinetics of marrow engraftment were analyzed in 50 patients with acute leukemia (21), malignant lymphoma (15), and solid tumors (14) after high-dose multiagent chemotherapy followed by autologous bone marrow transplantation (ABMT) with nonfrozen bone marrow. Unseparated heparinized whole bone marrow was stored in 10% CPDA1 at 4 degrees C for 72 h, then filtered and reinfused. The median number of nucleated cells reinfused was 1.6 x 10(8)/kg (range 0.5-3.8 x 10(8)/kg). All patients had a full hematopoietic reconstitution. Median time to achieve a neutrophil count greater than 500/microliters was 20 days (range 12-39) and median time to achieve an unsupported platelet count greater than 20,000/microliters was 20 days (range 10-55). The main factor associated with delayed engraftment was the number of prior chemotherapy cycles. We conclude that high-dose chemotherapy with nonfrozen ABMT is a safe procedure, without the requirement for costly cryopreservation facilities.

Differentiating agents facilitate infection of myeloid leukemia cell lines by monocytotropic HIV-1 strains

Monocytotropic human immunodeficiency virus type 1 (HIV-1) isolates from patients with acquired immunodeficiency syndrome (AIDS) infect mononuclear phagocytes as well as activated T cells, but do not usually infect immature human myeloid cell lines in vitro. The HL-60 promyelocytic/myeloblastic cell line and the promonocytic line, U937, were susceptible to productive infection by monocytotropic HIV-1 isolates (HIV-1JR-FL and HTLV-IIIBa-L) after treatment with retinoic acid, dimethyl sulfoxide, dibutyryl cAMP, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), or 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Virus production was only detected when these compounds were added before virus infection. Virus replication did not correlate with CD4 receptor expression because undifferentiated HL-60 cells express CD4 and the level of CD4 expression did not increase after differentiation in the presence of retinoic acid, 1,25(OH)2D3, or TPA. A mature monocytic cell line (THP-1) was capable of infection without pretreatment, and treatment with differentiating agents enhanced virus production. A chronically infected cell line (J-HL-60) was isolated after HIV-1JR-FL infection of HL-60 cells treated with retinoic acid. Virus production in this cell line was enhanced more than 10-fold after differentiation in the presence of 1,25(OH)2D3 or TPA. The majority of virus production by 1,25(OH)2D3-treated J-HL-60 cells was associated with the mature, adherent population. Molecular analysis of a cloned line of J-HL-60 showed integration of a single DNA provirus. These results suggest that cellular factors associated with precursor cell differentiation along the myelomonocytic pathway are required for optimal replication of monocytotropic HIV-1 strains in vitro.

Alternative splicing of the Evi-1 zinc finger gene generates mRNAs which differ by the number of zinc finger motifs

Evi-1 is a common integration site for endogenous ecotropic virus in myeloid leukemias of the AKXD mouse strain. This gene encodes a zinc finger protein with ten finger motifs. Myeloblastic leukemias obtained after infection with F-MuLV frequently exhibit proviral integration in the Fim-3 region which is genetically linked to Evi-1. This proviral integration always results in the expression of two mRNA transcripts, 5.7 kb and 4.7 kb long. We isolated two classes of cDNAs from a myeloblastic cell line with a F-MuLV provirus integrated in Fim-3. By sequence analysis, we found that one Evi-1 cDNA (E29) had an internal deletion of 972 nucleotides when compared to the full-length sequence previously published by Morishita et al. (1988). This deletion eliminated the 6th and 7th Evi-1 finger domains and was bordered by consensus donor and acceptor splice sequences. The E29 clone most likely resulted from alternative splicing of the Evi-1 gene. This was confirmed by Northern blot analysis and S1 mapping experiments. Therefore, the Evi-1 gene codes potentially for at least two proteins of 1042 and 718 amino acids differing in the numbers of their zinc-finger motifs.

Molecular cloning and characterization of a defective recombinant feline leukaemia virus associated with myeloid leukaemia

The GM1 strain of feline leukaemia virus (FeLV) was isolated from a naturally occurring case of myeloid leukaemia and induces severe haematopoietic abnormalities, including myeloblastic leukaemia, on inoculation into cats. Molecular clones of FeLV-GM1 proviruses were obtained and studied by restriction enzyme mapping, blot hybridization and partial DNA sequence analysis. Two types of clone were isolated; the first was a replication-competent FeLV of subgroup A, resembling other low or minimally pathogenic FeLV-A isolates; the second was replication-defective with extensive deletions and mutations in gag and pol, although it has an intact env gene of subgroup B phenotype. Large segments of the defective proviruses, from the 5' leader sequence upstream of the gag gene to the 5' half of the env gene, show structural hallmarks of endogenous FeLV-related proviruses. Infectious FeLV-GM1 viruses recovered after transfection were tested for their leukaemogenic potential in newborn cats. Early polyclonal myeloproliferative changes were observed in cats inoculated with FeLV-A/GM1 alone, although these were more pronounced in animals receiving the full FeLV-AB/GM1 complex reconstituted by cotransfection of the defective virus FeLV-B with its FeLV-A helper. Analysis of viruses in the bone marrow showed that replication of the subgroup B component is delayed and restricted to a proportion of cats. Most of the infected cats developed persistent abnormalities of haematopoiesis and one progressed to disseminated myeloid leukaemia. The defective recombinant FeLV-B/GM1 appears to play an indirect but important role in myeloid leukaemogenesis.

Changes in binding of staphylococcal leukocidin to HL-60 cells during differentiation induced by dimethyl sulfoxide

The susceptibility of HL-60 cells to the cytotoxic activity of leukocidin increased depending on the degree of differentiation induced by dimethyl sulfoxide (DMSO). To compare binding characteristics of two components (S and F) of leukocidin to HL-60 and DMSO-treated HL-60 cells, the S and F components were labeled with 125I. Scatchard analysis of the binding curve of the 125I-labeled S component to HL-60 cells showed two classes of binding sites. The binding sites with higher affinity had a dissociation constant of 3.39 nM, and the number of binding sites per cell was 730. The specific binding of the 125I-labeled S component to DMSO-treated cells increased depending on the period of DMSO treatment. Scatchard analysis of the binding curve of cells treated with DMSO for 7 days gave a straight line. The dissociation constant was 1.78 nM, and the number of binding sites per cell was 6,920. The total binding of the 125I-labeled F component to DMSO-treated cells increased about twofold over binding to HL-60 cells. However, in the presence of the unlabeled S component, the increase of binding of the F component to DMSO-treated cells was much greater. These data suggested that the increased susceptibility of DMSO-treated cells to leukocidin was dependent on the changes in the number of high-affinity binding sites of the S component and of the bound F component.

Monoclonal antibodies to HSV-infection-related antigens cross-react with tumor cell lines and tumor tissue sections

The purpose of our study was to evaluate a possible association between herpes simplex virus (HSV) and various tumors, including oral squamous cell carcinoma (SCC). To this end, we tested the binding of appropriate monoclonal antibodies to a panel of cell lines and tumor sections. The 25 monoclonal antibodies were reactive with HSV-infected cells but not with uninfected cells. Of these antibodies, three bound to several SCC cell lines and to one non-SCC cell line (K562). One of these three antibodies also reacted with sections of oral SCC tumors, the adjacent mucosa, and normal esophageal epithelium. In contrast, it did not bind to sections of kidney, spleen, esophageal smooth muscle, and skin. To evaluate whether the observed antibody binding could reflect an actual infection by HSV, hybridization experiments between K562 DNA and HSV DNA were performed. HSV DNA sequences were found in K562 DNA at a ratio of 0.1 genome-equivalents/cell. Although these data do not characterize the nature of the relationship, they clearly confirm the postulated association of HSV with some tumors (in particular oral SCC).

Chromosomal location of Evi-1, a common site of ecotropic viral integration in AKXD murine myeloid tumors

The chromosomal location of Evi-1, a common site of ecotropic viral integration in AKXD murine myelogenous leukemias, was determined by recombinant inbred and conventional backcross analyses. We mapped Evi-1 to a location approximately 15 cM distal to the carbonic anhydrase locus on murine Chromosome 3. The chromosomal location of the proto-oncogene Nras, and two growth factors, epidermal growth factor (Egf), and the beta subunit of nerve growth factor (Ngfb), which had previously been assigned to Chromosome 3 by somatic cell hybrid analysis, were also determined. The location of Evi-1 is distinct from these three loci and from all other proto-oncogenes, common sites of viral integration, or growth factor loci previously mapped in mouse chromosomes. These results suggest that Evi-1 represents a new locus involved in myeloid disease.

Moloney murine leukemia virus-induced myeloid tumors in adult BALB/c mice: requirement of c-myb activation but lack of v-abl involvement

BALB/c mice treated with pristane and Abelson virus have been used as an animal model system for the rapid induction of plasmacytomas. Myelomonocytic tumors with helper Moloney murine leukemia virus clonally inserted into the c-myb locus were observed in about 10% of pristane-primed BALB/c mice infected with Abelson virus. However, v-abl was absent in almost all of those tumors. Since Moloney virus is thought to induce mostly T-cell lymphomas, we have carried out studies to investigate this alteration of disease specificity and to determine whether v-abl played an obligatory role in the development of these tumors. We found that, whereas lymphomas developed late (greater than 3 months) in both pristane-primed and unprinted control mice, the myelomonocytic tumors arose at a high frequency, within 3 months, but only in pristane-treated mice. Clonal Moloney virus insertion was again found in each of the seven myelomonocytic tumors examined. Northern blot analyses and S1 mapping studies revealed the presence of virally promoted chimeric mRNAs that lack the three 5'-most myb coding exons. Hence it appears that the requirement for the v-abl gene product in tumor induction is not obligatory. Our results also indicate that tumor-specific alteration at the 5' end of the myb gene plays an important role in the development of these tumors.

Detection of hepatitis B virus DNA sequences in bone marrow of children with leukemia

To investigate the possibility that hemopoietic cells may become infected with hepatitis B virus (HBV), viral DNA was studied by molecular hybridization in bone marrow aspirates of 51 children with leukemia. HBV-DNA was found in the bone marrow of eight children (15%) and Southern blot analysis revealed the presence of free, monomeric viral sequences. Only one of the eight children with HBV-DNA in bone marrow cells was HBsAg-positive in serum, whereas two additional patients were transiently HBsAg-positive in serum during follow-up, but were negative at the time HBV-DNA was found in bone marrow. Four other cases developed antibodies to HBV. Cases of myeloid leukemia were more frequently positive for HBV-DNA in bone marrow (55%), compared with cases of lymphoid leukemia (7%). These results indicate that hemopoietic cells are susceptible to infection with hepatitis B virus and stimulate new interest into the relation of HBV infection to the development of some forms of leukemia, as four of eight cases of myeloid leukemia were HBV-DNA positive in bone marrow aspirates at diagnosis, prior to receiving any transfusion therapy.

Phorbol ester-induced growth arrest of murine myelomonocytic leukemic cells with virus-disrupted myb locus is not accompanied by decreased myc and myb expression

A class of mouse neoplasms termed Abelson virus-induced plasmacytoid lymphosarcomas has previously been found to express abnormal myb transcripts due to a helper virus insertion into the 5' end of the c-myb locus. We have established clonal cell lines from these tumors and have shown that they all express markers characteristic of myelomonocytic, rather than lymphoid, cells. Treatment of the plasmacytoid lymphosarcoma lines with phorbol 12-myristate 13-acetate led to various degrees of growth arrest, presumably due to myelomonocytic differentiation. To date, characterization of myeloid cell lines with varying responses to phorbol 12-myristate 13-acetate has not been reported. The different clonal plasmacytoid lymphosarcoma lines should, therefore, provide a good model to help elucidate the role of altered myb locus and other protooncogenes in myelomonocytic leukemia. Contrary to studies on induced differentiation of myelomonocytic cells with normal myb locus, our results on plasmacytoid lymphosarcoma cells indicate that reduced myb and myc expression may not be obligatory for growth arrest to occur. The present study, however, supports the previous notion that the myb transforming ability may be restricted to cells of the myelomonocytic lineage. In addition, we found that only the more mature cells can undergo prolonged phorbol 12-myristate 13-acetate-induced growth arrest, suggesting that the maintenance of these leukemic cells in their proliferative state, presumably by the myb gene product, can be overcome with appropriate differentiation signal(s).

Detection of HSV1 DNA by in situ hybridisation in human brain after immunosuppression

Human brain cells were examined for the presence of herpes simplex virus type 1 (HSV1) DNA sequences by in situ hybridisation. Viral genome was detected in immunosuppressed patients with virological evidence of past HSV infection but not in immunosuppressed patients with no such evidence. In patients who had not been immunosuppressed, no HSV DNA sequences were detectable.

Leukemogenicity of avian oncovirus S13

Avian oncovirus S13 induces erythroblastic and granulocytic leukemias in line 6 and Spafas chickens. It also causes anemia, sarcomas, and endothelial proliferation. The leukemic cells contain the transformation-specific protein of S13, gp155.

Two families of abl-related transcripts in human haematopoietic cells differing in their homology to v-abl

The transforming gene of the Abelson murine leukaemia virus, v-abl, contains two open reading frames (orf). The 5' orf encodes a tyrosine-specific protein kinase while the 3' orf has the capacity to code for an 18,000 Mr protein. However, no 3' orf product has yet been identified. Using probes capable of distinguishing between the 5' and 3' orfs of v-abl, we have examined the abl-related transcripts present in human haematopoietic cells and leukaemia-derived cell lines, including the chronic myeloid leukaemia-derived cell line K562. Our results indicate that transcripts of 6 kb, 7 kb and 8 kb (kilobase, 10(3) base-pairs) show strong homology to v-abl 5' protein kinase-encoding orf sequences, but are devoid of any sequences from the v-abl 3' orf. In addition, transcripts of 5 kb, 3 kb, 1.6 kb and 1.4 kb, reacting with both 5' orf and 3' orf probes, were observed. The latter species, with coding sequences from both the tyrosine kinase and the putative 18,000 Mr protein, must be transcribed from the human c-abl gene as this is apparently the only human gene containing sequences homologous to the v-abl 3' orf. The 6 kb, 7 kb and 8 kb transcripts may arise either from the c-abl gene through differential splicing, or from one of the three other regions of the human genome with sequences homologous to the 5' orf of v-abl. Examination of genomic DNA from the K562 cell line revealed that the amplification of abl-related sequences, which is presumed to result in the elevated levels of the 8 kb transcript found in this cell line, does not involve sequences homologous to the v-abl 3' orf. This lends credence to the idea that the 8 kb transcript may derive from an abl-related gene other than c-abl. While the significance of the 3' orf of v-abl remains unknown, the data presented strongly suggest the existence of at least two distinct abl-related proteins in human haematopoietic cells.

IgG-subclass-specific CMV reactivity in bone marrow transplant recipients

IgG subclasses of cytomegalovirus (CMV) antiviral antibodies were determined in 37 donor-recipient pairs of bone marrow transplants (BMT). Bone marrow transplant recipients, like healthy persons, have a restricted immune reactivity, producing mainly two types of anti-CMV IgG: IgG1 and IgG3. Passively transfused specific antibody subclasses were readily measurable. Take of the transplant could be detected from the production of subclass IgG antiviral antibody 1-3 months after BMT of seronegative recipients with marrow from seropositive donors. Patients with protracted CMV infections or other severe diseases initially also produced CMV IgG1 and IgG3, but anti-CMV subclass titers then decreased. In severe disease, CMV was isolated from blood cells as well as from urine. In moderate infections, in which the patients recovered, CMV was isolated from urine but usually not from blood, and a strong and durable antiviral subclass response was measured.