Acute promyelocytic leukaemia presenting as necrotising fasciitis of the perineum (Fournier gangrene).

We present a case of an unusual presentation of acute promyelocytic leukaemia (APML), which presented with Fournier gangrene (FG). A 38-year-old man presented with malaise, groin swelling, anal bleeding, fever and was found to have FG. Initial workup revealed pancytopaenia, borderline low fibrinogen, prolonged international normalized ratio (INR), which raised the suspicion for leukaemia. The peripheral blood differential revealed leucopaenia with absolute neutropaenia and a 5% abnormal promyelocytes but no blasts, suspicious for APML. Bone marrow biopsy was performed and fluorescence in situ hydridization (FISH), karyotype and PCR confirmed a t(15;17) translocation, establishing a diagnosis of APML. After 1 month of therapy for intermediate risk APML with All-trans retinoic acid (ATRA) and arsenic trioxide (ATO), repeat chromosomal analysis and repeat bone marrow biopsy revealed no evidence of residual APML. After the consolidation phase was started with ATRA and ATO regimen, the wound healed after 2 months and the patient achieved complete remission.

Infections in pediatric acute promyelocytic leukemia: from the Canadian infections in acute myeloid leukemia research group.

BACKGROUND: It is not known whether children with acute promyelocytic leukemia (APL) have an infection risk similar to non- APL acute myeloid leukemia. The objective was to describe infectious risk in children with newly diagnosed APL and to describe factors associated with these infections. METHODS: We conducted a retrospective, population-based cohort study that included children ≤ 18 years of age with de novo APL treated at 15 Canadian centers. Thirty-three children with APL were included; 78.8% were treated with APL -specific protocols. RESULTS: Bacterial sterile site infection occurred in 12 (36.4%) and fungal sterile site infection occurred in 2 (6.1%) children. Of the 127 chemotherapy courses, 101 (79.5%) were classified as intensive and among these, the proportion in which a sterile site microbiologically documented infection occurred was 14/101 (13.9%). There was one infection-related death. CONCLUSIONS: One third of children with APL experienced at least one sterile site bacterial infection throughout treatment and 14% of intensive chemotherapy courses were associated with a microbiologically documented sterile site infection. Infection rates in pediatric APL may be lower compared to non- APL acute myeloid leukemia although these children may still benefit from aggressive supportive care during intensive chemotherapy.

Invasive pulmonary aspergillosis: role of early diagnosis and surgical treatment in patients with acute leukemia.

BACKGROUND: Aspergillus is a ubiquitous soil-dwelling fungus known to cause significant pulmonary infection in immunocompromised patients. The incidence of aspergillosis has increased during the past two decades and is a frequently lethal complication of acute leukemia patients that occurs following both chemotherapy and bone marrow transplantation. The diagnosis of invasive pulmonary aspergillosis (IPA) according to the criteria that are established by European Organization for the Research and Treatment of Cancer and Mycoses Study Group raise difficulties in severely ill patients. Despite established improvements in field of diagnosis (galactomannan antigen, quantitative PCR, real-time PCR for Aspergillus spp., and findings of computed tomography) and treatment with new antifungals, it is still a major problem in patients with acute leukemia. However, prompt and effective treatment of IPA is crucial because most patients will need subsequent chemotherapy for underlying hematologic disease as soon as possible. CASE PRESENTATION: We report a 33-year-old male patient with acute promyelocytic leukemia diagnosed in 1993 that developed invasive pulmonary aspergillosis due to A. flavus at relapse in 2003. The patient was successfully treated with liposomal amphotericin B and underwent surgical pulmonary resection. The operative course was uneventful. CONCLUSION: This report emphasizes the clinical picture, applicability of recent advances in diagnostic and therapeutic approaches for IPA. For early identification of a patient infected with IPA, a high index of suspicion and careful clinical and radiological examinations with serial screening for galactomannan should be established. If aspergillosis is suspected, anti-aspergillosis drug should be administered immediately, and if a unique pulmonary lesion remains, surgical resection should be considered to prevent reactivation during consecutive chemotherapy courses and to improve the outcome.

Microscopic, cultural and molecular evidence of disseminated invasive aspergillosis involving the lungs and the gastrointestinal tract.

A patient with acute promyelocytic leukaemia developed invasive aspergillosis post chemotherapy during a pancytopenic episode, clinically involving the lungs and the gastrointestinal tract. Dichotomously branched septate fungal hyphae were demonstrated microscopically in stools and sputa. Cultures of the samples yielded Aspergillus flavus, which were identical by RFLP and random amplification of polymorphic DNA analyses and antifungal MICs, proving disseminated disease. To the best of the author's knowledge, this is the first time that boluses of fungal hyphae have been demonstrated microscopically in the stools of a patient with gastrointestinal aspergillosis.

Infection by Rhodotorula sp. in children receiving treatment for malignant diseases.

Rhodotorula sp. are commensal yeasts that may cause opportunistic infections. There have been only a few case reports of Rhodotorula fungemia in children with cancer, and in all of them the patients had a central venous catheter inserted. The authors report three nonfatal cases of fungemia by Rhodotorula in patients with post-chemotherapy neutropenia. Two of three patients required catheter removal, and a response was achieved with systemic antifungal therapy. Aggressive therapy may be required for selected high-risk patients.

Synthesis and antioxidant activity of 3-substituted guaiazulene derivatives.

A series of 3-substituted guaiazulene derivatives has been synthesized and their antioxidant properties were evaluated by monitoring their capacity for scavenging the stable free-radical DPPH. 3-Vinylguaiazulene was the most potent, possessing antioxidant activity superior than alpha-tocopherol. These derivatives were also moderate inhibitors of the proliferation of human promyelocytic leukemia cells.

Life threatening acute epiglottitis in acute leukemia.

We report an 8-year-old boy who developed a life-threatening acute epiglottitis during induction chemotherapy for acute promyelocytic leukemia. He survived the infection with emergency tracheostomy, treatment with broad spectrum antibiotics and amphotericin, and the use of granulocyte-macrophage colony stimulating factor. No organism was identified. A literature review identified 18 cases of acute epiglottitis in cancer patients. Sixteen of them were suffering from hematologic malignancies and three patients had received bone marrow transplantation. Unlike the usual case of epiglottitis, the majority (15 out of 18) of affected patients were adults and none of the infections was associated with Haemophilus influenzae. Streptococcus pneumoniae and Candida albicans were the most frequently identified pathogens. Early recognition and aggressive supportive care are required for successful management.

Cellular changes and induction of apoptosis in human promyelocytic HL-60 cells infected with the agent of human granulocytic ehrlichiosis (HGE).

Human granulocytic ehrlichiosis (HGE) is an emerging and occasionally fatal human infectious disease whose pathogenesis is largely unknown. Goodman et al. (1) recently described the successful cultivation of the HGE infectious agent in human promyelocytic HL-60 leukemic cells. It was reported in the same study that infectivity invariably led to host cell death, although the mechanism by which HGE infection triggers cellular self-destruction is as yet undetermined. In this communication, we show that in vitro passage of HGE pathogen-infected blood elicits a significantly dysfunctional G1-to-S transition. Moreover, we provide evidence that the cytopathic properties of the HGE pathogen are attributed to its ability to induce apoptosis in host HL-60 cells. Determination of specific protein expression changes by Western blot analysis showed that HGE infection resulted in reduced expression of PCNA and pRB, both of which play a role in cell cycling. Moreover, the steady state level of bcl-2, which protects eukaryotic cells against apoptosis, is suppressed by exposure to the HGE agent. These results suggest that this pathogen HGE induces apoptosis in HL-60 cells by a mechanism involving the shut-off of multiple cell cycle and apoptosis regulatory events.

Fatal Mycobacterium avium complex disease in a patient with acute nonlymphoblastic leukemia.

PURPOSE: The objective of this article was to present the diagnosis of a fatal infection by Mycobacterium avium complex (MAC) in a child with acute myelogenous leukemia, a disease rarely reported in non-HIV infected children. METHODS: Specific identification of MAC was made by culture in BACTEC system from an open lung biopsy. RESULTS: A 5-year-old girl diagnosed with acute nonlymphoblastic leukemia was admitted because of fever during the maintenance phase after achieving a complete remission of her malignancy. A mild dry cough started on day 4 of admission, and a chest roentgenogram revealed a pulmonary infiltrate. An insidious respiratory distress developed and mechanical ventilation was undertaken. An open-lung biopsy, carried out on day 10 of ventilatory support, revealed acid-fast bacilli subsequently grown as MAC. In spite of combined antimycobacterial treatment, the patient followed a downhill course and died on day 41 of hospitalization. CONCLUSION: This report describes a new case of fatal MAC infection in an immunocompromised, non-HIV infected child. MAC must be added to the list of infectious microorganisms that can infect children with acute nonlymphoblastic leukemia. As modern immunosuppressive therapeutic modalities evolve, it is likely that MAC will become a more common and recognized pathogen in the immunocompromised child.

Involvement of the sphingomyelin pathway in autocrine tumor necrosis factor signaling for human immunodeficiency virus production in chronically infected HL-60 cells.

Tumor necrosis factor (TNF) is a potent inducer of human immunodeficiency virus (HIV) proviral transcription and subsequent mature virus production. Recent investigations have shown that TNF can use a signal transduction pathway in HL-60 cells involving sphingomyelin hydrolysis to ceramide with subsequent stimulation of a ceramide-linked kinase. When sphingomyelinase was added exogenously to activate this cascade in HIV-1-infected HL-60 cells, it mimicked TNF-induced HIV production. Phospholipases A2, C, or D, which do not generate ceramide, had no effect; however, a synthetic ceramide analog added exogenously potently induced HIV production. In addition, anti-TNF antibodies blocked much of the effect of both sphingomyelinase and the synthetic ceramide analog on virus expression, suggesting that, although signaling is initiated through the sphingomyelin pathway, it is sustained by autocrine TNF synthesis. Thus, direct activation of the sphingomyelin pathway recapitulated the effect of TNF on both HIV and TNF production. These studies indicate that the sphingomyelin pathway is involved in TNF signaling for HIV production in chronically infected myeloid cells.

Tumor necrosis factor-dependent production of human immunodeficiency virus 1 in chronically infected HL-60 cells.

Tumor necrosis factor (TNF) may play a central role in proviral activation and release from latency in cells infected with the human immunodeficiency virus (HIV). We studied viral production and its relation to TNF in a HL-60 cell line (J22-HL-60) infected with a monocytotropic strain of HIV-1JR-FL. Viral production was stimulated to similar levels by TNF, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), and 1,25-dihydroxyvitamin D3 (1,25[OH]2D3). Production of the virus was not suppressed by 3'-azido-3'-deoxythymidine (AZT), indicating that viral production was not caused by superinfection. Low concentrations of TNF (0.1 ng/mL) induced viral production with a short lag period of 8 hours, and this proviral activation was specifically suppressed by anti-TNF antibodies. However, induction of virus production by 1,25(OH)2D3 showed an extended lag period of 2 to 3 days. The effect of 1,25(OH)2D3 on virus production was also blocked by anti-TNF antibodies, which suggests the direct participation of TNF in this process. TNF accumulated in the culture supernatant of cells stimulated with 1,25(OH)2D3 with a kinetics consistent with its involvement in the action of 1,25(OH)2D3 on viral production. The J22-HL-60 cell line produced low levels of virus when cultured in the absence of an external stimulus; however, this basal viral production was suppressed greater than 80% in the presence of anti-TNF antibodies. Corresponding low levels of TNF were detected in the culture supernatants. Viral production decreased slowly with increasing passage of the cells, and no virus was detected in the supernatants of cells maintained in culture for several months. Concomitantly, TNF was no longer detected in the supernatant of these cells, which suggests that endogenous autocrine production of TNF drives viral production in the unstimulated cells. However, viral production was stimulated in these cells by low concentrations (0.1 ng/mL) of added TNF. These results argue for a central role for TNF in HIV proviral activation in chronically infected myeloid cells.

Intracellular multiplication of Legionella pneumophila in HL-60 cells differentiated by 1,25-dihydroxyvitamin D3 and the effect of interferon gamma.

We examined leukemic cells, HL-60, an acute promyelocytic leukemia cell line, after differentiation induced by 1,25-dihydroxyvitamin D3 (D3) and retinoic acid (A) for infection of Legionella pneumophila, the etiologic agent of Legionnaires' disease. We investigated the effect of interferon gamma (IFN-gamma) on the differentiated cells and on the intracellular growth of the bacteria. An examination of morphological and antigenic changes in the cells was also included in the study. After 4-day incubation with 10(-6)M D3 or A, the HL-60 cells differentiated into monocyte-like (D3-HL-60) or mature granulocyte-like (A-HL-60) cells, respectively. They were then infected with L. pneumophila. Intracellular multiplication of the bacteria was evident in D3-HL-60 cells but not in HL-60 or A-HL-60 cells. D3-HL-60 cells required a 24-h infection time for the intracellular growth of L. pneumophila. D3-HL-60 cells activated with human recombinant IFN-gamma for 1-24 h (gamma-IFN-D3-HL-60 cells) before infection markedly inhibited L. pneumophila multiplication, the effect of IFN-gamma being dose dependent. Surface marker analysis was carried out in HL-60, D3-HL-60, and gamma-IFN-D3-HL-60 cells. On D3-HL-60 cells, CD11b, CD11c, CD14, and CD35 antigen increased, whereas CD71 and HLA-DR antigen decreased. This finding suggested that HL-60 cells differentiated into monocyte-like cells; the acquisition of the complement receptors, CD11b(CR3) and CD35(CR1), seemed to be important for phagocytosis and for the subsequent intracellular multiplication of L. pneumophila. The gamma-IFN-D3-HL-60 cells showed an increase of CD16, CD36, CD71, and HLA-DR antigen, suggesting that they were in an activated state. Our study indicated, first, that D3 can induce human leukemic cells to differentiate into functional monocyte-macrophage-like cells that can support the intracellular multiplication of L. pneumophila and, second, that these differentiated leukemic cells can be activated by IFN-gamma to markedly inhibit bacterial growth.

Regulation of HIV-1 expression by cytokine networks in a CD4+ model of chronic infection.

Using the CD4+ model of chronic HIV-1 infection, OM-10.1, we investigated the influence of TNF-alpha regulatory networks on induced viral expression. Previously, OM-10.1 cultures were characterized to respond to exogenous TNF-alpha, as nearly 100% of the cells were activated to express HIV-1 within 24 h. In this study, OM-10.1 cells were pulse-treated, by applying exogenous factors for short periods of time and then washing, to determine if autocrine TNF-alpha could sustain HIV-1 activation in the absence of additional exogenous stimulation. After a TNF-alpha pulse treatment, the progressive increase of HIV-1-expressing OM-10.1 cells was prevented by the continuous presence of anti-TNF-alpha mAb. The inductive activity of supernatant from TNF-alpha pulse-treated OM-10.1 cultures was completely removed by absorption on immobilized anti-TNF-alpha mAb. In addition, TNF-alpha pulse-treated OM-10.1 cells activated HIV-1 expression in untreated OM-10.1 cells when cultured across a permeable membrane indicating paracrine effects. Interestingly, if TNF-alpha pulse-treated OM-10.1 cells were further pulse-treated with anti-TNF-alpha mAb, a marked reduction in autocrine TNF-alpha was observed although the level of newly synthesized TNF-alpha mRNA remained unaffected. A similar degree of inhibition over autocrine TNF-alpha production was observed when soluble TNF receptors were used as the second pulse treatment in these experiments. Although the applicability of these results to in vivo chronically HIV-1-infected cells remains to be realized, these results do indicate that activated HIV-1 expression can be influenced by self-perpetuating mechanisms during periods of limited exogenous stimulation. Furthermore, physiologic mechanisms involving soluble cytokine receptors that counteract autocrine and paracrine activation of HIV-1 expression are shown here to play a regulatory role.

Involvement of the spleen in preleukemic development of a murine retrovirus-induced promonocytic leukemia.

An acute myeloid leukemia can result from the inoculation of Moloney murine leukemia virus into BALB/c mice undergoing a 2,6,10,14-tetramethylpentadecane-induced chronic inflammatory response in the peritoneal cavity. This leukemia is ultimately observed in the peritoneal cavity as an ascites with cells infiltrating the granulomatous tissue. It has been proposed, however, that hematopoietic organs such as the spleen and bone marrow are involved in preleukemic development of Moloney murine leukemia. Therefore, to determine if the spleen plays a role in this development, mice were splenectomized at various times relative to virus inoculation. When splenectomies were performed 3 days before and 2, 4, 6, and 8 weeks after virus inoculation there was, in all cases, a decreased death rate compared to sham-splenectomized controls. The greatest difference in death rate due to promonocytic leukemia was observed when mice were splenectomized at 4 weeks after virus inoculation. The decrease in disease incidence observed as a result of splenectomy was not caused by decreased virus spread in hematopoietic organs or an alteration in the profile of the cellular infiltrate in the granuloma. It was found, however, that the spleens of 2,6,10,14-tetramethylpentadecane-treated mice, relative to those of normal mice, have a significantly increased number of granulocyte-macrophage colony-forming cells and a slightly increased number of multipotential colony-forming cells. These observations suggest that a population of target cells for transformation, consisting of granulocyte-macrophage precursor cells, may reside in the spleen. Alternatively, partially transformed cells may reside temporarily in the spleen during the developmental stages of the disease process.