Viral infections in juvenile myelomonocytic leukemia: prevalence and clinical implications

OBJECTIVES: Viral infections may complicate the diagnosis of juvenile myelomonocytic leukemia (JMML) in a substantial proportion of patients, but this possibility has not been tested in a prospective study. The authors therefore measured the cellular expression of the MxA protein, a reliable marker of viral infection, at diagnosis in children with JMML to estimate the prevalence of such infections. METHODS: Eighteen children, aged 1 to 69 months, who met the diagnostic criteria of the International JMML Working Group were prospectively studied. MxA expression was assessed by flow cytometric analysis of peripheral blood mononuclear cells stained with an antihuman MxA antibody. All data were obtained through the MDS Committee of the Japanese Society of Pediatric Hematology. RESULTS: Twelve patients (67%) had elevated levels of the MxA protein, with rotavirus, RS virus, or CMV infection documented in three of these patients. Although none of the patients had primary Epstein-Barr virus (EBV) infection, reactivation of the virus was strongly suspected in four children, including two with monosomy 7, each having increased levels of MxA. Southern blot analysis revealed monoclonal integration of the EBV genome into bone marrow mononuclear cells from one of these patients. There was no discernible correlation between increases in the marker protein and the presenting features or course of the disease. CONCLUSIONS: Viral infection may be present in two thirds of children with newly diagnosed JMML, but it does not constitute a basis for revising clinical management. The possibility that EBV or other viruses contribute to JMML pathogenesis by stimulating pre-exiting malignant clones warrants further investigation.     

Diagnostic Dilemma of JMML Coexisting with CMV Infection

Juvenile myelomonocytic leukemia (JMML) is a rare mixed myeloproliferative and myelodysplastic disorder of early childhood, characterized by excessive proliferation of monocytic and granulocytic cells, along with myelodysplastic features. There are reports of viral infections mimicking JMML, with all clinical and hematological parameters normalizing on resolution of infection. The authors describe a 1- year- old boy with concomitant JMML and CMV infection. The diagnostic dilemma, the significance of distinguishing it from a mimicking viral infection, as well as potential synergistic effect of concomitant infections on the presentation or actual disease severity of underlying JMML will be discussed.     

Cytomegalovirus infection mimicking juvenile myelomonocytic leukemia showing hypersensitivity to granulocyte–macrophage colony stimulating factor

We describe an infant with cytomegalovirus (CMV) infection presenting as transient myeloproliferation resembling juvenile myelomonocytic leukemia (JMML). The patient fulfilled the international diagnostic criteria of JMML, including hypersensitivity to granulocyte–macrophage colony‐stimulating factor (GM‐CSF). Viral studies using serologic assays and polymerase chain reaction (PCR) were positive for CMV. Clinical symptoms disappeared and laboratory values returned to normal without specific treatment within 1 year. Follow‐up showing a decrease in viral titers suggested CMV infection as an etiologic factor for the development of myeloproliferative features. We conclude that the CMV infection transiently induced abnormal myelopoiesis in this infant. Pediatr Blood Cancer 2009; 53:1324–1326. © 2009 Wiley‐Liss, Inc.     

Alpha-Thalassämie-Retardierungs-Syndrom

Alpha-thalassemia X-linked mental retardation (ATRX, MIM#301040) syndrome is associated with severe mental retardation, muscular hypotonia, facial dysmorphism, and genital anomalies in males. We present the case of a family with two affected boys. The diagnosis was made by maternal X-chromosome inactivation studies which showed marked skewing of maternal X-chromosome inactivation and ATRX analysis revealed a novel mutation in exon 34.     

Juvenile chronic myelogenous leukemia: differentiation from infantile cytomegalovirus infection

Differentiation between cytomegalovirus (CMV)-associated disease and juvenile chronic myelogenous leukemia (JCML) in infants excreting CMV may be difficult. It is important to make a prompt, definitive diagnosis since the management differs. A 3-month-old infant presented with clinical findings that mimicked both disorders and a plan was developed to make the correct diagnosis. Clonogenic assays and liquid cultures of patients' peripheral blood and bone marrow showed findings that are recognized as the hallmark of JCML, namely, impaired growth of normal hematopoietic progenitors, and excessive, autonomous proliferation of monocyte/macrophage elements. The urine was positive for CMV, and there was a significant rise in the anti-CMV antibody titer over 4 weeks, indicating a postnatal CMV infection. Despite this, freshly obtained and cultured marrow cells as well as a liver biopsy were negative for CMV by immunoassay, by anti-CMV monoclonal antibody testing, and by electron microscopy. Because of these results, the diagnosis of CMV infection was established but could not account for all of the abnormal clinical and hematological findings. Thus, the diagnosis of JCML was also substantiated and antileukemic therapy was initiated with confidence.     

Human herpesvirus 6 infection mimicking juvenile myelomonocytic leukemia in an infant

In vitro cell culture studies of bone marrow and peripheral blood progenitor cells from patients with juvenile myclomonocytic leukemia (JMML) consistently show spontaneous proliferation and selective hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF). This GM-CSF hypersensitivity dose-response assay has become a component of the international diagnostic criteria for JMML. The authors report a 2-week-old boy with perinatal human herpesvirus 6 (HHV-6) infection in whom in vitro bone marrow culture studies suggested the diagnosis of JMML by showing increased spontaneous proliferation, inhibition of this growth by anti-GM-CSF antibodies, and hypersensitivity to GM-CSF. Polymerase chain reaction viral studies from whole blood DNA and the shell vial viral culture assay were both positive for HHV-6. The patient's condition improved with expectant treatment, with an eventual return to normal blood counts and resolution of hepatosplenomegaly. This case of perinatal HHV-6 infection shows that viruses can initially mimic the in vitro culture results found in patients with JMML. It also illustrates that patients suspected of having JMML should be observed if there are no signs of progressive disease and concurrent features suggestive of viral infection.     

Utilisation des tests virologiques pour le diagnostic,le pronostic et la surveillance des infections congénitales à cytomégalovirus

Cytomegalovirus (CMV) infection is the main cause of congenital infection in industrialized countries. The virological tools used for the diagnosis of congenital CMV are serology for diagnosis of primary infection in the mother, CMV PCR in amniotic fluid for diagnosis of fetal infection, PCR in urine or saliva for neonatal diagnosis and PCR in dried blood spots on Guthrie cards for retrospective diagnosis in young children. The prognostic value of viral load in amniotic fluid, fetal blood and neonatal blood will be discussed. The performance of the virological tests for antenatal or postnatal screening of congenital CMV will also be discussed.     

Quantitative analysis of CMV DNA in children the first year after liver transplantation

CMV infection is a major problem after solid organ transplantation especially in children where primary infection is more common than in adults. Early diagnosis is critical and might be facilitated by quantitative analysis of CMV DNA in blood. In this retrospective study of 18 children who had a liver transplantation 1995-2000, serum samples were analysed by Cobas Amplicor Monitor (Roche). Four patients developed symptomatic CMV infection at a mean time of 4 wk after transplantation. They showed maximum CMV DNA levels in serum of 26 400, 1900, 1300 and 970 copies/mL, respectively. In comparison, CA Monitor was positive, at a low level (415 copies/mL), in one of 11 patients with asymptomatic (4) or latent (7) infection. CMV IgM was detected at significant levels (> or =1/80) in all four patients with symptomatic, and in one with asymptomatic CMV infection. Eight patients were given one or several courses of ganciclovir. Five of these lacked symptoms of CMV disease, and had low (415 copies/mL) or undetectable CMV DNA in serum. The data suggest that quantitative analysis of CMV DNA may be of value in early identification of CMV disease and for avoiding unnecessary antiviral treatment.     

流式细胞术检测PP65抗原血症在诊断巨细胞病毒感染上的应用

目的　探讨流式细胞技术检测PP6 5抗原血症对巨细胞病毒 (CMV)感染的诊断价值。方法　对 136例CMV感染患儿流式细胞技术检测血PP6 5抗原、实时荧光定量PCR(RFQ PCR)检测尿CMVDNA及血清ELISA法检测CMVIgM ,比较 3种方法的检测结果 ,并以 35例非CMV感染的患儿作为PP6 5检测的阴性对照。对 18例PP6 5抗原阳性患儿进行短期随访。结果　 136例CMV感染患儿从血单个核细胞 (MNC)中检出PP6 5抗原 118例 (118/ 136 ,阳性率 86 8% )。其中 5 3例患儿分别作MNC和多形核白细胞 (PMNL)检测 ,从MNC中检出PP6 5抗原 4 5例 (45 / 5 3,阳性率 84 9% ) ,PMNL中检出PP6 5抗原 4 3例 (43/ 5 3,阳性率 81 1% ) ,MNC与PMNL阳性率差异无统计学意义 (χ2 m=0 2 5 ,P >0 0 5 )。PP6 5与尿CMVDNA2种方法所检测的结果间差异无统计学意义 (χ2 m=1 78,P >0 0 5 ) ;但PP6 5与血CMVIgM检测结果间差异有统计学意义 (χ2 m=5 2 92 ,P <0 0 1)。PP6 5抗原水平与CMV感染的病情程度有明显相关性 ,全身性感染通常伴高水平抗原血症 ,单脏器感染抗原水平相对较低或阴性(χ2 =38 5 1,P <0 0 0 5 )。PP6 5在感染恢复期转为阴性或低水平 ,病情恶化时明显增高。结论　流式细胞技术检测PP6 5抗原血症是诊断活动性CMV感染的有效手段 ,量化结     

Development of T-cell acute lymphoblastic leukemia in a patient in very long lasting complete remission of juvenile myelomonocytic leukemia

Juvenile myelomonocytic leukemia (JMML) occurs with an incidence of 1.2 per million children a year, and represents 18% to 30% of all myelodysplastic (MDS) and myeloproliferative (MPS) disorders in the age group below 15, being by far the most common MDS/MPS in children younger than 4 years. The only therapeutic approach which results in a definitive cure of patients with JMML is myeloablative chemo-therapy/radio-therapy, followed by allogeneic hematopoietic cell transplantation. Few cases of transformation of JMML in acute lymphoblastic leukemia have been reported. We describe a child with JMML diagnosed at the age of 4 months in whom complete remission was achieved with 13-cis retinoic acid and cytosine-arabinoside and was sustained for 7 years with no maintenance therapy. Ninety-eight months after the diagnosis of JMML was established, overt T-cell leukemia developed. Treatment with acute lymphoblastic leukemia (ALL)-directed chemotherapy induced complete restoration of normal hemopoiesis, but testicular involvement persisted. The patient died after transplantation with unrelated cord blood. This case suggests that JMML is a true stem cell disorder and that stem cell transplantation should be considered, even in patients with a very favorable clinical course.     

Post-transfusion cytomegalovirus infection in premature infants weighing less than 1,500 g

The incidence of cytomegalovirus (CMV) infection among 107 low birth weight transfused infants (birth weight less than or equal to 1,500 g) admitted to an intensive care nursery over an 18 month period was evaluated. The diagnosis of CMV infection was based on specific serologic tests (presence of IgM, increased IgG by ELISA technic) and identification of the virus in the urine. During the first 8 months, the infants received untested blood and CMV disease occurred in 8 infants out of 44 (18.2%). During the following 10 months, all transfusions performed in 63 infants were supposed to be CMV negative. However, 32 infants received untested blood due to emergency, and 5 of them developed a CMV infection (15.6%). Finally, only 31 infants received CMV negative blood without any case of CMV infection. These data clearly demonstrate that, considering the severity of the CMV disease in the premature infants, transfusions should be performed with CMV negative blood products.     

Strategies to prevent CMV infection in the neonate

Congenital cytomegalovirus (CMV) infection is a major cause of sensorineural hearing loss and mental retardation, whose annual healthcare costs in the USA approximate to one billion dollars. Only a minority of neonates with this infection has symptoms present at birth and some of the damage to ear and brain occurs in the first few months of life. Extensive studies of CMV infection have been conducted in pregnant women and their children to define the natural history of this infection. What is required now is a concerted commitment to tackle this clinical problem using one or more of the following strategies: avoid iatrogenic transmission; advise those at risk how to avoid acquisition; provide diagnosis in an individual neonate or pregnant woman and offer treatment; develop and deploy a CMV vaccine.     

Congenital cytomegalovirus infection in twin pregnancies: viral load in the amniotic fluid and pregnancy outcome

Human cytomegalovirus (CMV) is the most common cause of viral intrauterine infection and fetal damage largely attributable to maternal primary infection. Most cases of congenital CMV infection in twins reported in the literature involved only 1 twin. We assessed the validity of polymerase chain reaction (PCR) and quantitative PCR on amniotic fluid (AF), at 21 to 22 weeks' gestation and at least 6 to 8 weeks after seroconversion, to predict the outcome of newborns in twin pregnancies. Two pregnant women with twin pregnancies and 1 woman with a triple pregnancy with primary CMV infection defined by the presence of immunoglobulin (Ig) M and low IgG avidity and/or by the presence of clinical symptoms and abnormal liver enzyme values were evaluated. CMV infection was found in 6 fetuses/newborns, 3 of whom were symptomatic. In the first twin pregnancy with diamniotic-dichorionic separate placentas, CMV symptomatic infection of the female twin was demonstrated by positive virus isolation and high viral load in AF. The male fetus was not infected as demonstrated by negative CMV culture and DNA detection in AF. In the triple pregnancy, the woman had a placenta with 2 monozygotic twins (females) and a separate placenta with a heterozygotic twin (male). The quantitative PCR results were 10(3) genome equivalents (GE)/mL of females AF and 1.9 x 10(5) GE/mL of male AF. Both female twins were asymptomatic at birth, whereas the male presented petechiae, thrombocytopenia, and cerebral ventriculomegaly. In the last twin pregnancy with fused dichorionic placentas, congenital CMV infection of both twins was diagnosed at birth in contrast with prenatal diagnosis. At time of amniocentesis, the left side twin was not infected as shown by negative results of CMV culture and DNA detection in the AF. CMV infection of the right side twin was demonstrated by positive CMV DNA detection with a CMV DNA load of 4.9 x 10(4) GE/mL and positive virus isolation in the AF. The morphologic and histologic examinations of the placentas strongly supported a prenatal horizontal acquisition of CMV infection. These twin pregnancies showed a marked difference in the quantity of virus load documented by the prenatal diagnosis suggesting that twin fetuses may react differently to primary maternal infection despite being exposed to the same maternal influences. A high viral load is correlated with congenital CMV infections symptomatic at birth. In such cases, with fetal infection of only 1 twin (at amniocentesis) and fusion of placentas, fetal outcome of both twins needs to be evaluated for the possibility of viral transfer from one fetus to the other.     

Gastrointestinal manifestations of postnatal cytomegalovirus infection in infants admitted to a neonatal intensive care unit over a five year period

Sixteen cases of postnatal cytomegalovirus (CMV) infection were identified in a neonatal intensive care unit population over a five year period. Eleven of these infants had gastrointestinal signs at the time of presentation. These ranged from minor and transient (abdominal distension and enteral feed intolerance) to severe and life threatening (protein losing enteropathy, diarrhoea, and hypernatraemic dehydration). An initial diagnosis of necrotising enterocolitis was common, but no infant showed intestinal or hepatic portal pneumatosis. The gestational age of the infants was 24-38 weeks. All had received fresh maternal breast milk. It is suggested that CMV enteritis is added to the spectrum of clinical manifestations of postnatal CMV infection. Signs suggestive of necrotising enterocolitis with atypical features should prompt investigations for CMV infection.     

Cytomegalovirus infection and wheezing in infants

Background: Bronchial asthma‐like symptoms such as wheezing are commonly associated with respiratory tract infection including respiratory syncytial virus (RSV) infection in infants. No study on the association of wheezing with cytomegalovirus (CMV) infection in infancy has been reported, although CMV infection has been observed to play some role in prolonged and intractable wheezing in limited cases. Methods: The present study investigated 40 hospitalized infants who presented with first‐episode wheezing between October 2003 and September 2004. Nasopharyngeal aspirates were tested for RSV, and serum antibodies against CMV were measured. As controls, age‐matched infants with no wheezing were examined for CMV serostatus. Results: RSV‐antigen was detected in 21 subjects (53%), and seven (18%) were considered primary CMV infection serologically. Primary CMV infection was found more often in the wheezers than in the controls although the difference was not statistically significant (P = 0.06). The incidence of splenomegaly was significantly higher in wheezers with CMV infection (86%) than in those with RSV infection or without either infection. The duration of wheezing, fever, and radiographic and laboratory findings during hospitalization were not significantly different. Conclusions: CMV infection based on serologic diagnosis should be considered in infants with first wheezing episode and particularly those with splenomegaly.     

DIAGNOSIS OF CONGENITAL CYTOMEGALOVIRUS INFECTION BY EXAMINATION OF PLACENTA: Application of Polymerase Chain Reaction and in Situ Hybridization

We examined the placentas of 12 patients in whom congenital cytomegalovirus CMV infection was suspected from serological and or pathological evaluation. Seven patients died including four intrauterine deaths and five survived. On histological examination, the characteristic inclusion bodies were detected in only three placentas, and villitis with plasma cell infiltration was seen in eight placentas. Immunohistochemistry using a specific antibody against CMV improved the sensitivity of CMV detection 10 cases were positive . With the polymerase chain reaction PCR following the extraction of DNA from formaldehyde-fixed placenta samples, CMV DNA was detected in seven cases. All 12 subjects were diagnosed with CMV infection by additional Southern blot analysis after the PCR. CMV DNA was also detected by an in situ hybridization method in all cases. With current molecular biological techniques the placenta can be reliably used for the diagnosis of congenital CMV infection.     

Juvenile myelomonocytic leukemia and Noonan syndrome

A case of juvenile myelomonocytic leukemia (JMML, previously referred to as JCML) in a neonate with Noonan syndrome (NS) is described. The boy presented with bilateral congenital hydrothoraces, nonimmune hydrops, dysmorphic facies, persistent thrombocytopenia, and leukocytosis. The diagnosis of JMML was made on bone marrow cell culture studies. Review of the literature reveals an unusual preponderance of hematologic malignancies, in particular JMML, among patients with NS. Of 40 NS patients admitted to the authors' institution during a 10-year period, there were 4 (10%) with evidence of a monocytic proliferation, which resolved spontaneously. The authors postulate that patients with NS may have an increased incidence of myeloproliferative disorders, which in most cases appears to be benign but may be preleukemic or even lethal.     

Differentiating juvenile myelomonocytic leukemia from chronic myeloid leukemia in childhood

Juvenile myelomonocytic leukemia (JMML) is a rare clonal myeloproliferative disease of early childhood. To determine the diagnostic features, appropriate treatment, and overall patient survival pertaining to JMML for children, the authors reviewed the clinical data of 16 children with JMML admitted to the National Taiwan University Hospital between 1978 and 2001. Median age at diagnosis was 2.5 years. Fever was the most common symptom at diagnosis. At initial presentation, the mean white blood count and absolute monocyte count were 30 x 10(9)/L and 4.5 x 10(9)/L, respectively. Cytogenetic analysis was performed in 14 patients, and 2 patients (14%) had monosomy 7. Another patient, with normal karyotype at diagnosis, had deletion of 7q22 at the follow-up chromosome study. Forty-seven chronic myeloid leukemia (CML) patients were also diagnosed and followed at the same hospital during the same interval period. The age, leukocyte counts, platelet counts, basophil counts, monocyte percentages on peripheral blood smears, and median survival rate showed significant differences between JMML and CML patients (P < 0.05). The median survival was 10 months and the probability of 10-month survival was 0.38 by Kaplan-Meier analysis for 12 of the 16 JMML patients who did not receive hematopoietic stem cell transplantation (HSCT). Among three patients receiving HSCT, one patient relapsed 9 months after the first HSCT and was treated successfully by a second HSCT from the same sibling donor.     

Prevalence and clinical aspects of congenital cytomegalovirus infection

OBJECTIVES: The objectives of the present study were to determine the prevalence of congenital CMV infection, as well as to evaluate the importance of this agent as cause of congenital disease, and to describe the clinical manifestations in children attended at a General Hospital in Ribeir?o Preto, SP, Brazil. POPULATION AND METHODS: A first group including 189 newborns and their mothers was evaluated for the prevalence of the congenital CMV infection. A second group including 130 newborns and 74 infants who presented clinical manifestations of congenital disease were also investigated to evaluate the importance of the CMV as a cause of this disease and to describe the clinical findings. Diagnosis of congenital CMV infection was established by detecting the virus using viral isolation in tissue culture, polymerase chain reaction DNA amplification in urine samples and detection of specific anti-CMV IgM and IgG by immunofluorescence indirect test. RESULTS: The prevalence of congenital CMV infection was 2.6% and the prevalence of CMV antibodies in mothers was 95%. In the first group, none of the 5 congenitally infected presented clinical apparent disease at birth, although one of them had intracranial calcifications. In the second group, CMV was recognized as a causative of congenital disease in 12 children (5.9%). Of these, 10(83%) were identified after the neonatal period. The clinical findings included hepatosplenomegaly (75%), jaundice with direct hyperbilirubinemia (42%), neurologic disease consisting of microcephaly and intracranial calcifications in 42% of these children. CONCLUSIONS: The prevalence of congenital CMV infection was similar to that reported in other studies about highly immune populations. Infants with asymptomatic congenital CMV infection may have diseases of the central nervous system that are not clinically evident at birth, such as punctate calcifications. CMV infected patients who are symptomatic at birth have a multisystem disease, and the differential diagnosis of any newborn with clinical abnormalities including involvement of the hepatobiliary, hematopoietic and central nervous systems should include congenital CMV infection. CMV was an important agent of these abnormalities, and the majority of symptomatic patients were identified after the neonatal period, making the diagnosis more difficult.     

Strong response of T cells in infants with dual infection by Epstein–Barr virus and cytomegalovirus

BACKGROUND: Although a reversed CD4/CD8 ratio and increased proportion of CD8+ HLA-DR+ T cells are well known as the characteristic immune response in infectious mononucleosis (IM), it has not been elucidated whether these immune responses are affected by patient age and pathogenetic viruses. METHODS: T cell subsets were analyzed by two-color flow cytometry using fluorescein isothiocyanate- and phycoerythrin-conjugated monoclonal antibodies in 115 infants and children aged from 4 months to 10 years with IM due to Epstein-Barr virus (EBV), cytomegalovirus (CMV) and dual infection with both viruses. RESULTS: A reversed CD4/CD8 ratio and increased proportions of CD4+/HLA-DR+ T cells, CD8+ T cells and CD8+/HLA-DR+ T cells became more prominent as the age of the patients became older. No differences were observed in proportions of T cell subsets between EBV- and CMV-infection among patients aged from 6 to 17 months. Although the responses of these T cells were weak in infants with single virus infection by EBV and CMV, markedly strong T cell responses comparable with those in older children were observed in infants with EBV/CMV dual infection. Clinical symptoms were more severe in patients with EBV/CMV dual infection than those with EBV or CMV alone. CONCLUSION: The manner of these T cell responses in the acute phase of IM was considered to be age dependent, although strong T cell responses and severe disease were observed in EBV/CMV dual infection irrespective of patient age.