Transcripto E2A-PBX1 en paciente pediátrico con leucemia aguda híbrida linfoide b/mieloide / E2A-PBX1 transcript in pediatric patient with acute hybrid lymphoid b/myeloid leukemia

Las leucemias agudas representan un grupo heterogéneo de hemopatías malignas que pueden ser de origen linfoide o mieloide en dependencia del clon celular que da lugar al proceso maligno. Sin embargo, existen casos de leucemias agudas con fenotipo mixto donde coexisten características propias de más de un linaje celular y que se conocen hoy como leucemias agudas de fenotipo mixto. Se presenta el caso de un paciente que se diagnosticó como una leucemia aguda híbrida linfoide B/mieloide mediante citometría de flujo. Se encontró la presencia del gen de fusión E2A-PBX1 que se forma como consecuencia de una traslocación entre los cromosomas 1 y 19. El paciente, un niño de 20 meses de nacido, falleció a los 12 días de iniciados los primeros síntomas clínicos. Se conoce que esta anormalidad cromosómica está asociada a un pronóstico desfavorable, principalmente por la grave afectación del sistema nervioso central como en efecto ocurrió. Hasta donde se alcanzó a revisar, no se encontró un reporte similar en la literatura de una leucemia aguda híbrida linfoide B/mieloide positiva al gen defusión E2A-PBX1(AU)

The acute leukemias are an heterogenous group of malignant hemopathies diseases characterized by excessive proliferation of an inmature cellular clon. Depending of the myeloid or lymphoid origin of such clon, the acute leukemia could be classified in myeloid or lymphoid respectivement. However, there are cases of acute leukemias with mixed phenotype where immunologic markers of more than on elineage are present. In the patient of this report was founded a mixed immunophenotype pattern by flow cytometry and the entity was classified as acute hybrid lymphoid B/ mieloid leukemia. Basedon theinicial diagnostic of acutelymphoidleukemia, the molecular studydiscoveredthepresence of E2A-PBX1 fusion gen. That molecular anomaly is formed as consequence of a traslocation between the1 and 19 chromosomes. The patient, a child of 20 months, died 12 days afte rthe first clynic symptoms begining. E2A-PBX1 fusion gen is associated to unfavorable outcome, mainly because the severe damage at the central nervous system as in fact it occurred. Until it was possible review, no any similar report was founded about a case of acute hybrid lymphoidB/myeloid leukemia positive to the E2A-PBX1 fusion gen(AU)

Fatal Cyberlindnera fabianii fungemia in a patient with mixed phenotype acute leukemia after umbilical cord blood transplantation.

We report a case of Cyberlindnera fabianii fungemia after umbilical cord blood transplantation (CBT). A 69-year-old woman was diagnosed as having mixed phenotype acute leukemia. The patient received CBT for primary refractory disease. After preconditioning chemotherapy, the patient's condition deteriorated, leading to acute respiratory failure from capillary leak syndrome and consequent admittance to the intensive care unit. The patient recovered temporarily following the administration of noninvasive positive pressure ventilation and continuous hemodiafiltration, but died of fungemia with the presence of yeast-like cells 15 days post-CBT. The yeast-like cells were analyzed by sequencing of the D1/D2 domain of the large subunit and the internal transcribed spacer domain, and were identified as C. fabianii. This case shows that molecular genetic-based methods may be effective for detecting undetermined invasive fungal infections in stem cell transplantation settings.

Renal Presentation in Pediatric Acute Leukemia: Report of 2 Cases.

Renal enlargement at time of diagnosis of acute leukemia is very unusual. We here in report 2 pediatric cases of acute leukemia who had their renal affection as the first presenting symptom with no evidences of blast cells in blood smear and none of classical presentation of acute leukemia. The first case is a 4-year-old girl who presented with pallor and abdominal enlargement. Magnetic resonance imaging showed bilateral symmetrical homogenous enlarged kidneys suggestive of infiltration. Complete blood picture (CBC) revealed white blood count 11 × 109/L, hemoglobin 8.7 g/dL and platelet count 197 × 109/L. Bone marrow aspiration was performed, and diagnosed precursor B-cell ALL was made. The child had an excellent response to modified CCG 1991 standard risk protocol of chemotherapy with sustained remission, but unfortunately relapsed 11 month after the end of therapy. The second child was 13-month old, presented with pallor, vomiting, abdominal enlargement, and oliguria 2 days before admission. Initial CBC showed bicytopenia, elevated blood urea, creatinine, and serum uric acid, while abdominal ultrasonography revealed bilateral renal enlargement. Bone marrow examination was done and showed 92% blast of biphenotypic nature. So, biphynotypic leukemia with bilateral renal enlargement and acute renal failure was subsequently diagnosed. The patients admitted to ICU and received supportive care and prednisolone. Renal function normalized and chemotherapy was started. The child achieved complete remission with marked reduction of kidney size but, unfortunately she died from sepsis in consolidation phase of therapy. This case demonstrates an unusual early renal enlargement in childhood acute leukemia. Renal involvement of acute leukemia should be considered in child presenting with unexplained bilateral renal enlargement with or without renal function abnormalities and bone marrow examination should be included in the workup.

The relationship between cerebrospinal fluid osteopontin level and central nervous system involvement in childhood acute leukemia.

The aim of this study was to evaluate the relationship between cerebrospinal fluid (CSF) osteopontin (OPN) levels and central nervous system (CNS) involvement in children with a diagnosis of acute leukemia. The study sample consisted of 62 patients who had been diagnosed with acute leukemia. The control group consisted of 16 patients that had presented and had no malignant disease, CNS infection or chronic disease. CSF OPN levels were studied with enzyme-linked immunosorbent assay (ELISA) method. The mean CSF OPN level was 32.76±49.22 ng/ml in the patients at the time of diagnosis and 14.93±6.84 ng/ml in the control group (p>0.05). The mean CSF OPN level was 27.68±32.73 ng/ml at the time of diagnosis in the group without CNS involvement and 53.48±89.21 ng/ml in the group with CNS involvement (p>0.05). However, the CSF OPN level at the time of CNS relapse in patients who developed CNS involvement during follow-up (127.4±52 ng/ml) was significantly higher than in the group without CNS involvement at diagnosis and follow-up (mean CSF OPN level: 27.68±32.73 ng/ml) (p<0.001). The analysis of CSF OPN levels at the time of diagnosis-before relapse and at the periods of relapse and remission in patients who had CNS involvement at diagnosis and/or follow-up revealed statistically significant differences between the time points (p<0.001). High CSF OPN levels in childhood acute leukemia patients may be used as evidence for CNS involvement, and any increases found in CSF OPN levels may be a preliminary predictor for CNS involvement.

Disseminated amphotericin-resistant fusariosis in acute leukemia patients: report of two cases.

Disseminated fusariosis has emerged as a significant, usually fatal infection in immunocompromised hosts despite antifungal treatment. We describe here two patients with acute leukemia who developed disseminated amphotericin-resistant fusariosis, and review of six studies of cases series in the literature. Two Fusarium solani strains were isolated from blood and skin cultures of one patient, and one strain from the blood culture of the second patient. Both patients died despite antifungal treatment. Strains were identified by sequencing of ITS1 and ITS4 regions. Random amplified polymorphic DNA analysis of the three F. solani isolates showed a low degree of similarity. Screening for Fusarium spp. contaminants within our facility was negative. Using the CLSI M-38-A2 broth dilution method and E tests(®), we found that the MICs were low for voriconazole (0.12 and 0.5 mg/L, respectively), unexpectedly high for amphotericin B (≥8 and ≥32 µg/mL, respectively) and itraconazole (≥16 mg/ml). Patients with leukemia or persistent neutropenia should be assessed for disseminated fungal infections, including biopsy and skin cultures. Antifungal susceptibility tests are important due to the possibility of the strains being amphotericin resistant. Treatments must be aggressive, with high doses of antifungals or combined therapy.

Candida krusei fungemia in an immunocompromised patient.

Candida krusei is an emerging fungal pathogen found primarily in immunocompromised patients. Intrinsic resistance to fluconazole and decreasing susceptibility to other anti-fungal agents are problematic. When colonization occurs, dissemination may follow rapidly. We present a case of a patient with acute lymphoblastic leukemia who, despite being treated prophylactically with fluconazole, developed disseminated C. krusei.

Successful living donor liver transplantation for severe hepatic GVHD histologically resembling autoimmune hepatitis after bone marrow transplantation from the same sibling donor.

A 30-year-old woman developed severe liver dysfunction 1 year after bone marrow transplantation (BMT) from an HLA-identical sibling donor for B lymphoblastic leukemia (B-ALL) during the tapering of cyclosporin A. The histologic picture resembled autoimmune hepatitis (AIH), although neither autoantibody nor hypergammaglobulinemia was detected. She entered hepatic coma, and underwent living donor liver transplantation from the same donor on day 421 after BMT. She is well 18 months after the procedure, showing normal liver function and hematopoiesis. AIH-like hepatic graft-versus-host disease (GVHD) has not been documented. This patient is the second case of living donor liver transplantation for hepatic GVHD from the same donor.

Successful voriconazole treatment of invasive pulmonary aspergillosis in a patient with acute biphenotypic leukemia.

A 23-year old woman with acute biphenotypic leukemia (ABL) complained of chest pain with cough, high fever and hemoptysis during induction chemotherapy, although she had been treated with anti-biotics and micafungin. We made a clinical diagnosis of invasive pulmonary aspergillosis (IPA) based on a consolidation in the right upper lung field on a chest radiograph as well as a high level of serum beta-D-glucan (with no evidence of tuberculosis and candidiasis). We changed her treatment from micafungin to voriconazole. Later, we discovered an air-crescent sign by CT scan that supported the diagnosis of IPA. Following voriconazole treatment, clinical symptoms ceased and abnormal chest shadows improved gradually and concurrently with a recovery of neutrophils. IPA must be considered in immunocompromised patients with pulmonary infiltrates who do not respond to broad-spectrum antibiotics. Serological tests and CT findings can aid in early diagnosis of IPA, which, along with treatment for IPA, will improve clinical outcomes.

Controversies of and unique issues in hematopoietic cell transplantation for infant leukemia.

Infants with leukemia who require hematopoietic cell transplantation (HCT) remain 1 of the most significant challenges in pediatric stem cell transplant. Infant leukemia is characterized by a unique biology including a predominance mixed lineage leukemia(MLL) gene rearrangement and juvenile myelomonocytic leukemia. Moreover, the long-term effects of transplantation are particularly prominent in infants who have active endocrine, cardiovascular, pulmonary, neurologic, musculoskeletal, hearing, and vision development, with the added risk of second malignant neoplasms. Currently, there is no solid basis to support allogeneic HCT as first-line therapy for infant acute lymphoblastic leukemia-first remission (ALL-CR1), although indicated for other infant leukemias, including juvenile myelomonocytic leukemia (JMML). The relative long-term toxicity of total body irridiation (TBI) versus non-TBI containing preparative regimens for HCT in infants remains controversial, with the differences, especially on neurocognitive function, unknown.

Fulminant septicemia of Bacillus cereus resistant to carbapenem in a patient with biphenotypic acute leukemia.

We report a case of fulminant septicemia with Bacillus cereus resistant to carbapenem. A 33-year-old man was suffering from febrile neutropenia (FN) on day 15 after the start of remission-induction therapy for biphenotypic acute leukemia under gut decontamination with polymyxin B and nystatin. Meropenem, a carbapenem, was administered according to the guideline for FN. Two days later (on day 17), he complained of severe abdominal pain, lost consciousness, went into sudden cardiopulmonary arrest, and died. Autopsy showed multiple spots of hemorrhage and necrosis caused by bacterial plaque in the brain, lungs, and liver. B. cereus was isolated from a blood sample obtained in the morning on day 17 and it was after his death that the isolated B. cereus was revealed to be resistant to carbapenem. B. cereus obtained from blood samples has been reported to be usually sensitive to carbapenem and also to vancomycin, new quinolones, and clindamycin. If B. cereus resistant to carbapem increases, our method of gut decontamination with polymyxin B and nystatin may have to be changed to one containing a new quinolone for the prevention of septicemia. Careful watching to determine whether B. cereus resistant to carbapem increases may be also important for empiric therapy, because carbapenem is often selected as the initial therapy for FN in patients with severe neutropenia.

Leukemia cutis presenting as localized cutaneous hyperpigmentation.

The usual clinical presentations of leukemia cutis include solitary infiltrated erythematous or violaceous plaques or nodules and multiple localized or generalized papules. On the other hand, cutaneous hyperpigmentation is a frequent finding in patients with malignancies, most of the cases because of chemotherapy or other drugs that the patient is taking. We present a case of cutaneous hyperpigmentation as the presenting sign of leukemia cutis. A 61-year-old male presented with cutaneous hyperpigmentation, which had appeared during the last chemotherapy cycle for treatment for biphenotypic leukemia. Cutaneous lesions consisted of bluish to brownish irregular well-defined discoloration of the skin involving the upper part of the trunk and the temporal regions of the forehead. The patient was asymptomatic and the skin was not infiltrated at all. However, histopathologic study showed nodular infiltrates involving the full-thickness of the dermis and destroying pre-existing adnexa. This infiltrate was composed of atypical basophilic cells with large hyperchromatic nuclei and scant cytoplasm. Immunohistochemical studies showed intense immunoexpression for CD43, CD68, CD45RO and myeloperoxidase within these cells. A diagnosis of biphenotypic leukemia cutis was established. In our review of the literature we have not found any report of cutaneous hyperpigmentation as the presenting manifestation of leukemia cutis.

Isolated foot ulcer complicating acute leukemia: an unusual manifestation of herpes simplex virus infection simulating pyoderma gangrenosum.

An isolated foot ulcer developed in a child with newly diagnosed acute mixed lineage leukemia during induction chemotherapy. Despite its clinical resemblance to pyoderma gangrenosum, herpes simplex virus infection was eventually diagnosed on histopathology. Treatment with oral acyclovir was ineffective, but the ulcer healed with intravenous acyclovir followed by oral valaciclovir. Viral infection remains an unusual but important cause of isolated extragenital cutaneous ulceration in the immunocompromised child.

Concurrent centrifugation plasmapheresis and continuous venovenous hemodiafiltration.

Continuous venovenous hemofiltration/hemodiafiltration (CVVH/D) is commonly used to provide renal replacement therapy for critically ill patients who are hemodynamically unstable. Occasionally, the addition of plasmapheresis therapy is necessary for some conditions, including immune-mediated acute renal failure, sepsis, fulminant hepatic failure, and thrombotic thrombocytopenic purpura/hemolytic uremic syndrome. Most tertiary care facilities provide centrifugation plasmapheresis instead of membrane plasmapheresis, because of the requirement for both therapeutic plasma exchange and pheresis of cellular blood products. We report a new technique where centrifugation plasmapheresis and CVVHD (P-CVVHD) are combined and used concurrently. Blood from the patient was concurrently filtered utilizing a Hospal BSM 22 machine with a Multiflow 60 hemofilter and a Cobe Spectra continuous cell separator in a parallel configuration. P-CVVHD is technically possible and can be used for long periods of time with limited risks. There may be advantages to P-CVVHD compared with discontinuous combined CVVH/D and plasmapheresis therapy.

Successful treatment of Wernicke's encephalopathy in a boy with acute mixed lineage leukemia.

A 12-year-old boy had been treated with multiagent chemotherapy for acute mixed lineage leukemia and with intravenous hyperalimentation due to persistent diarrhea and vomiting for 2 months. He suddenly complained of horizontal nystagmus and gait disturbance followed by oculomotor palsy and disorientation within a few days. Blood tests revealed low serum vitamin B1 and high serum pyruvate. Magnetic resonance imaging in T2-weighted axial image revealed a high signal inside the bilateral thalami, mamillary bodies and periaquaductal gray matter. He was diagnosed as Wernicke's encephalopathy and successfully treated with vitamin B1. Careful observation and adequate treatment are emphasized in the management of this preventable and curable disease.