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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two patients with sickle cell disease were diagnosed with aplastic crisis caused by acute parvovirus B19 infection. One patient also developed thrombocytopenia associated with hemophagocytic histiocytosis in the bone marrow biopsy. Both patients developed transient blood plasmacytosis and hypocomplementemia soon after admission to the hospital. Transient blood plasmacytosis may be an immunological response to acute parvovirus B19 infection.
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PMID:Transient blood plasmacytosis in parvovirus B19 infection: a report of two cases. 860 81

Acute Chest Syndrome (ACS) continues to be a major source of morbidity and mortality among patients with sickle cell disease. It is characterized by the presence of pleuritic chest pain, fever, raises on lung auscultation, and pulmonary infiltrates on chest x-ray [Castro et all: Blood 84:643-649]. The pathophysiology of this disorder remains poorly understood leading to the descriptive term "Acute Chest Syndrome" designated by Charache et al. [Arch Intern Med 139:67-69, 1979]. Typical bacterial pathogens are seldom isolated in adults, although they play a significant role in the pathogenesis of this entity in children. Until recently, the technology to accurately study viral infection as a precipitating cause of ACS has been unavailable. Parvovirus B19 is being increasingly recognized as an important human pathogen, and has been established as the cause of transient "aplastic crisis" in patients with sickle cell diseases [Saarien et al: Blood 67:-11411-11417, 1986; Young: Sem Hematol 25:159-172, 1988]. We present three patients with hemoglobin SC variant of sickle cell disease who developed ACS in association with acute parvovirus B19 infection, one of which died of respiratory failure. Parvovirus B19 infection was established by polymerase chain reaction for parvovirus B19 DNA, and the presence of parvovirus B19 specific IgM antibodies. These cases suggest that parvovirus B19 may be associated with more than self-limited illness in patients with sickle cell disease, and that this ubiquitous virus may merit further study as a precipitating cause of ACS.
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PMID:Sickle cell acute chest syndrome associated with parvovirus B19 infection: case series and review. 861 1

Transient aplastic crisis is reported in a young child with sickle cell anemia with acute B19 parvovirus infection. She also developed acute chest syndrome and bone marrow/bone infarction involving the right ilium. The clinically unsuspected bone marrow infarction in this patient may have contributed to acute chest syndrome secondary to pulmonary fat embolism. Transient cessation of erythropoiesis as a result of B19 parvovirus infection, and not the localized bone marrow infarction, was the probable cause of reticulocytopenia and worsening of anemia in this child.
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PMID:B19 parvovirus infection and transient aplastic crisis in a child with sickle cell anemia. 884 33

Parvovirus B19 is usually associated with an acute, self-limited disease in children. In patients with a congenital hemolytic anemia, infection with this virus can cause an aplastic crisis. We describe such a crisis in an adult with asymptomatic hereditary spherocytosis. The association between acute red blood cell aplasia and infection with parvovirus B19 is well described in patients with hereditary hemolytic anemia, particularly sickle cell anemia. This association has also been described, although less frequently, in patients with other inherited hemolytic diseases, such as hereditary spherocytosis. In children, human parvovirus B19 causes an acute self-limited illness known as erythema infectiosum (fifth disease). In immunocompromised individuals, chronic infections can occur and cause a severe, persistent anemia. In pregnant women, infection can, but usually does not, lead to fetal infection. An infected fetus can have severe anemia, congestive heart failure, generalized edema (fetal hydrops) and even death. Most cases of aplastic crises associated with parvovirus B19 in patients with hereditary spherocytosis have been reported in children and adolescents. In this paper we describe an aplastic crisis in a 28 year old man with asymptomatic hereditary spherocytosis.
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PMID:Aplastic crisis associated with parvovirus B19 in an adult with hereditary spherocytosis. 930 16

The role of known hematopoietic growth factors in the pathogenesis of aplastic anemia and congenital hypoplastic anemia has been extensively studied and no evidence has been obtained that deficiency of these factors contributes to the hypoproliferative state in these disorders. Clonal hematopoiesis seems to be present at least in a small percentage of cases of aplastic anemia, a finding that needs further investigation. Androgens were shown to be beneficial only for women with aplastic anemia treated with antilymphocyte globulin. Unrelated-donor bone marrow transplantation is becoming a realistic approach for children and very young adults with aplastic anemia, but in older groups the survival is very poor. New observations on abnormalities of lymphokines and cytokines in Fanconi's anemia have been described, but their pathogenetic significance remains unknown. A large number of studies have excluded the possibility that abnormalities of c-kit/SCF genes and their expression are responsible for the erythroid aplasia in Diamond-Blackfan syndrome. Cyclosporine was found to be an effective treatment for pure red cell aplasia associated with chronic lymphocytic leukemia. The cell membrane receptor for B19 parvovirus has been identified as the P antigen. Long-term studies showed that in 20% of patients with homozygous sickle cell disease, infection by B19 does not cause erythroid aplasia.
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PMID:Aplastic anemia and pure red cell aplasia. 937 Dec 75

Interleukins (IL)-1, 2, 12, and interferon (IFN)-gamma, along with soluble IL-2 receptor (sIL-2R) were measured from sera obtained from healthy sickle cell disease (SCD) patients and comparable healthy control subjects. The cytokines were assessed by enzyme-linked immunosorbent assay (ELISA) in 60 SCD patients and 58 controls. No significant detectable levels of IL-1 or IL-12 were found in the sera of either group of patients. Significantly elevated levels of IFN-gamma were measured in 20 (33%) of 60 SCD patients and 21 (36%) of 58 controls. A large subset of 18 (41%) of 43 healthy controls and a smaller subset of 12 (21%) of 58 SCD demonstrated detectable levels of IL-2. The sIL-2R levels of the SCD group (4465 +/- 552 pg/mL) were significantly higher (P < .0001) than that of controls (3473 +/- 411 pg/mL). The results revealed comparable circulating levels of all type 1 cytokines in both healthy SCD and normal control subjects, with the exception of in vivo sIL-2R production. Elevated serum levels of both IL-6 and tumor necrosis factor (TNF)-alpha have been reported previously in a significant percentage of SCD steady-state subjects. These two cytokines are known to increase sIL-2R expression and may help explain the difference between the patient populations. Immune activation markers such as sIL-2R are produced by cells that mediate host responses to infection or inflammatory stimuli. The implication of higher levels of sIL-2R in SCD is not clear, but chronic parvovirus B19 infection, chronic polyclonal activation of B cells or defective regulation of antibodies are possible explanations for the elevated levels in SCD.
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PMID:In vivo production of type 1 cytokines in healthy sickle cell disease patients. 1064 97

Human parvovirus B19 gene expression from the viral p6 promoter (B19p6) is restricted to primary human hematopoietic cells undergoing erythroid differentiation. We have demonstrated that expression from this promoter does not occur in established human erythroid cell lines in the context of a recombinant parvovirus genome (Ponnazhagan et al. J Virol 69:8096-8101, 1995). However, abundant expression from this promoter can be readily detected in primary human bone marrow cells (Wang et al. Proc Natl Acad Sci USA 92:12416-12420, 1995; Ponnazhagan et al. J Gen Virol 77:1111-1122, 1996). In the present studies, we investigated the pattern of expression from the B19p6 promoter in primary human bone marrow-derived CD34+ HPC undergoing differentiation into myeloid and erythroid lineages. CD34+ cells were transduced with recombinant adeno-associated virus 2 (AAV) vectors containing the beta-galactosidase (lacZ) gene under the control of the following promoters/enhancers: the cytomegalovirus promoter (vCMVp-lacZ), B19p6 promoter (vB19p6-lacZ), B19p6 promoter with an upstream erythroid cell-specific enhancer element (HS-2) from the locus control region (LCR) from the human beta-globin gene cluster (vHS2-B19p6-lacZ), and the human beta-globin gene promoter with the HS-2 enhancer (vHS2-beta p-lacZ). Transgene expression was evaluated either 48 h after infection or following erythroid differentiation in vitro for 3 weeks. Whereas high-level expression from the CMV promoter 48 h after infection diminished with time, low-level expression from the B19p6 and the beta-globin promoters increased significantly following erythroid differentiation. Furthermore, in HPC assays, there was no significant difference in the level of expression from the CMV promoter in myeloid or erythroid cell-derived colonies. Expression from the B19p6 and the beta-globin promoters, on the other hand, was restricted to erythroid cell colonies. These data further corroborate that the B19p6 promoter is erythroid cell-specific and suggest that the recombinant AAV-B19 hybrid vectors may prove useful in gene therapy of human hemoglobinopathies in general and sickle cell anemia and beta-thalassemia in particular.
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PMID:Adeno-associated virus 2-mediated transduction and erythroid lineage-restricted expression from parvovirus B19p6 promoter in primary human hematopoietic progenitor cells. 1064 62

Sickle cell anaemia (SCA) predisposes a child to infections for various reasons, including increased bone marrow turnover, poor perfusion and functional asplenia leading to decreased opsonisation of polysaccharide encapsulated organisms. Bacteria and viruses that most frequently cause serious infections in children with sickle cell disease are Streptococcus pneumoniae, Haemophilus influenzae type b, Salmonella spp., Escherichia coli, Staphylococcus aureus, Mycoplasma pneumoniae, Chlamydia pneumoniae, parvovirus B19 and hepatitis A, B and C viruses. Penicillin prophylaxis has decreased the incidence of infection-related morbidity and mortality significantly in children with SCA. Children <3 years of age are administered oral penicillin 125mg twice daily, and the dose is increased to 250mg twice daily for the >3 to 5 year age group. Adherence to the penicillin prophylactic regimen is recommended for children with SCA who are >5 years of age. For children with SCA who have recurrent invasive pneumococcal infections, an effort is made to keep the child on penicillin prophylaxis indefinitely. The administration of various childhood vaccines has also made an appreciable impact on the overall morbidity and mortality associated with infection in children with SCA. The administration of the heptavalent conjugate pneumococcal vaccine (PCV7) has provided control of invasive pneumococcal infections, and the prophylactic use of the H. influenzae type b conjugate vaccine has reduced the incidence of septicaemia and meningitis caused by this organism. Other vaccines used prophylactically in children with SCA include hepatitis A and B, and vaccines against influenza and varicella viruses. The immediate administration of intravenous antibacterials, after appropriate blood and urine cultures, is of great importance in the treatment of the febrile child with SCA. Ceftriaxone and cefotaxime have been recommended for the treatment of septic episodes in SCA associated with S. pneumoniae, Haemophilus and Salmonella spp. Infection with Yersinia enterocolitica may be treated with cefotaxime or an aminoglycoside. The prevalence of Helicobacter pylori infection in SCA is unknown. Effective therapies include metronidazole, tetracycline or amoxicillin. Parvovirus infections require supportive care and specific antiviral therapy is not indicated. The judicious use of antimicrobials is encouraged in view of the worldwide emergence of multidrug-resistant strains. The long term sequelae associated with infections in children with SCA can be decreased with the implementation of immunisation programmes and effective and prompt treatment with appropriate antibacterials.
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PMID:Prevention and management of infection in children with sickle cell anaemia. 1173 65

The prevalence of anti-human parvovirus B19 IgG antibodies was determined in sera from 165 chronic hemolytic anemia patients, receiving medical care at Instituto Estadual de Hematologia (IEHE), Rio de Janeiro, during the year of 1994. This sample represents around 10% of the chronic hemolytic anemia patients attending at IEHE. Most of these patients (140) have sickle cell disease. Anti-B19 IgG antibodies were detected in 32.1% of patients. No statistically significant difference (p > 0.05) was seen between IgG antibody prevalence in male (27.8%) and female (35.5%) patients. Anti-B19 IgG antibodies were more frequent in older (37.6%) than younger (28.2%) than 20 years old patients, although this difference had no statistical significance (p > 0.05). Anti-B19 IgG antibody prevalence showed that 67.9% of patients enrolled in the study were susceptible to B19 acute infection. With the aim to detect acute B19 infection, patients follow up continued until February 1996. During this period four patients presented transient aplastic crisis due to human parvovirus B19 as confirmed by the detection of specific IgM antibodies. All four patients were younger than 20 years old, and 3 were younger than 10 years old. Three of them were sickle cell disease patients. Three of the four acute B19 infection occurred during 1994 springtime.
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PMID:Study of chronic hemolytic anaemia patients in Rio de Janeiro: prevalence of anti-human parvovirus B19 IgG antibodies and the development aplastic crises. 1221 9

Human parvovirus (HPV) B19 causes significant morbidity and mortality in children with sickle cell disease (SCD), but little data are published about the epidemiology of HPV B19 infection and its associated complications in this patient population. In this study, prevalence and incidence rates of HPV B19 were determined in 633 patients with SCD followed at The Children's Hospital of Philadelphia between November 1996 and December 2001. Thirty percent (30%) were HPV B19 immunoglobulin G (IgG) positive at first testing, and the 70% without evidence of past HPV B19 infection were tested annually. One hundred ten patients developed evidence of HPV B19 infection for an incidence rate of 11.3 per 100 patient years. Sixty-eight episodes of HPV B19-induced transient red cell aplasia occurred with the following clinical events: fever (89.7%), pain (61.8%), acute splenic sequestration (19.1%), and acute chest syndrome (11.8%). Pain, fever, and acute splenic sequestration were more frequent events with acute HPV B19 infections compared with acute events in uninfected patients. The results of this epidemiologic study, the largest and most comprehensive to date, justify the development of HPV B19 prevention strategies to diminish the frequent and often severe complications associated with HPV B19 infections in patients with SCD.
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PMID:Epidemiology of human parvovirus B19 in children with sickle cell disease. 1452 77


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