Glomerular accumulation of plasmacytoid dendritic cells in active lupus nephritis: Role of interleukin‐18

Objective

Defective circulating dendritic cells (DCs) have been described in systemic lupus erythematosus (SLE) and correlated with high levels of interferon‐α (IFNα). DCs are differentiated as being either myeloid or plasmacytoid, according to chemokine expression and the tendency to migrate toward inflamed tissue. We investigated the potential role of interleukin‐18 (IL‐18) in driving the glomerular migration of DCs in lupus nephritis (LN) and in affecting the ability of DCs to induce an imbalance in the Th1:Th2 ratio.

Methods

DC subsets were characterized by flow cytometry and defined as either myeloid or plasmacytoid according to the expression of CD11c/blood dendritic cell antigen 1 (BDCA‐1) and CD123/BDCA‐2, respectively. The serum Th1:Th2 profile was studied by enzyme‐linked immunosorbent assay. IL‐18 receptor (IL‐18R) and other chemokine receptors were analyzed by flow cytometry. Glomerular levels of IL‐18/IL‐18R and the presence of plasmacytoid DCs and myeloid DCs were investigated by immunohistochemical analysis.

Results

The number of peripheral plasmacytoid DCs was decreased in patients with SLE compared with control subjects, and this defect in the number of DCs was correlated with LN. Patients with LN showed a prevalent Th1 response, with high production of IL‐18, IL‐12 and IFNγ. Only plasmacytoid DCs expressed IL‐18R. Patients with severe LN showed a high accumulation of IL‐18 within glomeruli in association with the presence of plasmacytoid DCs, whereas myeloid DCs were almost absent.

Conclusion

A deficient number of peripheral plasmacytoid DCs correlated with high levels of Th1 cytokines and was associated with LN. Both serum and glomerular IL‐18 were increased in LN. It is suggested that the high level of expression of IL‐18R by peripheral plasmacytoid DCs allows the DCs to relocate within glomeruli under IL‐18 stimulation and triggers the resident T cells, thus promoting renal damage.

     

Novel role of plasmacytoid dendritic cells in humans: Induction of interleukin‐10–producing treg cells by plasmacytoid dendritic cells in patients with rheumatoid arthritis responding to therapy

Objective

Reestablishing immune tolerance and long‐term suppression of disease represent major therapeutic goals in rheumatoid arthritis (RA). Dendritic cells (DCs) likely play a central role in such regulation via the expansion and/or induction of Treg cells. The present study was undertaken to explore the contribution of DCs to the development of Treg cells in a human autoimmune disease setting.

Methods

DC subsets were characterized by flow cytometry in the peripheral blood and synovial fluid of patients with RA. Proliferation of and cytokine release by naive CD4+CD25− T cells were measured in cocultures of these cells with DCs from patients with RA and healthy controls. The suppressive capacity of DC‐polarized T cells was explored in vitro by a standard suppression assay.

Results

Only very low numbers of both plasmacytoid DCs (CD303+) and myeloid DCs (CD1c+) were present in the peripheral blood of patients with active RA. In contrast, patients with therapy‐induced remission of RA exhibited higher numbers of circulating plasmacytoid DCs. Mature plasmacytoid DCs from RA patients with low disease activity, but not those from healthy controls, expressed high levels of indoleamine 2,3‐dioxygenase and promoted the differentiation of allogeneic naive CD4+CD25− T cells into interleukin‐10–secreting Treg cells, or Tr1 cells, that showed poor proliferation in vitro. Importantly, these plasmacytoid DC–primed Treg cells potently suppressed the proliferation of autologous naive CD4+ T cells, in a dose‐dependent manner.

Conclusion

These results demonstrate, for the first time, that human plasmacytoid DCs may be educated within the rheumatoid microenvironment to acquire a tolerogenic phenotype. Modulation of the immune response by plasmacytoid DCs might provide novel immune‐based therapies in autoimmunity and transplantation.

     

Lactate dehydrogenase and caspase activity in nasopharyngeal secretions are predictors of bronchiolitis severity

Background

Bronchiolitis is the leading cause of hospitalization in infants. Biomarkers of disease severity might help in clinical management.

Objective

To determine the clinical predictiveness of NW-LDH, NW-caspase 3/7, and NW-LDH/NW-caspase 3/7 ratio in bronchiolitis.

Methods

Previously healthy children less than 24 months of age with bronchiolitis were recruited from the Texas Children''s emergency room and intensive care unit from October 2010 to April 2011. Demographic, clinical information, and NW samples were obtained at enrollment. NW samples were analyzed for respiratory viruses, caspase 3/7, and LDH.

Results

A viral pathogen was detected in 91·6% of 131 children, with the most common being respiratory syncytial virus and human rhinovirus. A single infection was found in 61·8% of subjects and co-infection in 29·8%. Children admitted to ICU had significantly higher NW-LDH than children sent home from the ER or admitted to the general floor (P = 0·02). Children infected with RSV had the highest NW-LDH concentration (P = 0·03) compared with other viral infections. NW-LDH and NW-caspase were significantly correlated (r = 0·77, P < 0·0001). The univariate models showed NW-LDH and NW-LDH/NW- caspase 3/7 ratio were directly associated with hospitalization. Mutivariate regression analyses suggested a complex interaction between the biomarkers, demographics, and disposition.

Conclusions

NW-LDH, NW-caspase 3/7 and NW-LDH/NW-caspase 3/7 ratio and their interactions with demographic factors are predictive of bronchiolitis severity and can help distinguish children requiring ICU-level care from those admitted to the general floor, or discharged home from the emergency center.     

Clinical severity of rhinovirus/enterovirus compared to other respiratory viruses in children

Background

Human rhinovirus/enterovirus (HRV/ENT) infections are commonly identified in children with acute respiratory infections (ARIs), but data on their clinical severity remain limited.

Objectives

We compared the clinical severity of HRV/ENT to respiratory syncytial virus (RSV), influenza A/B (FLU), and other common respiratory viruses in children.

Patients/Methods

Retrospective study of children with ARIs and confirmed single positive viral infections on mid-turbinate swabs by molecular assays. Outcome measures included hospital admission and, for inpatients, a composite endpoint consisting of intensive care admission, hospitalization >5 days, oxygen requirements or death.

Results

A total of 116 HRV/ENT, 102 RSV, 99 FLU, and 64 other common respiratory viruses were identified. Children with single HRV/ENT infections presented with significantly higher rates of underlying immunosuppressive conditions compared to those with RSV (37·9% versus 13·6%; P < 0·001), FLU (37·9% versus 22%; P = 0·018) or any other single viral infection (37·9% versus 22·5%; P = 0·024). In multivariable analysis adjusted for underlying conditions and age, children with HRV/ENT infections had increased odds of hospitalization compared to children with RSV infections (OR 2·6; 95% CI 1·4, 4·8; P < 0·003) or FLU infections (OR 3·0; 95% CI 1·6, 5·8; <0·001) and increased odds of severe clinical disease among inpatients (OR 3·0; 95% CI 1·6,5·6; P = 0·001) when compared to those with FLU infections.

Conclusions

Children with HRV/ENT had a more severe clinical course than those with RSV and FLUA/B infections and often had significant comorbidities. These findings emphasize the importance of considering HRV/ENT infection in children presenting with severe acute respiratory tract infections.     

Blastic plasmacytoid dendritic cell neoplasm in children: diagnostic features and clinical implications

Background

Blastic plasmacytoid dendritic cell neoplasm is a rare malignancy that typically follows a highly aggressive clinical course in adults, whereas experience in children with this disease is very limited.

Design and Methods

This retrospective study analyzed the pathological and clinical findings of nine cases of blastic plasmactyoid dendritic cell neoplasm presenting in patients under the age of 18 years who were reviewed at our institution. We also identified 20 well-documented additional pediatric cases in the literature.

Results

In the combined analysis, the overall survival rate among the 25 patients with available follow-up, all having received chemotherapy, was 72% (follow-up ranging from 9 months to 13 years, with a median of 30 months). The event-free survival rate was 64%. Nine patients were alive 5 years after the original diagnosis, although only three of them had undergone hematopoietic stem cell transplantation – one in first complete remission and two in second remission. Of the seven patients who lacked cutaneous disease at presentation, 100% survived, including five who were alive more than 5 years after diagnosis, although only two had undergone stem cell transplantation. Among the 18 patients who presented with cutaneous disease and for whom follow-up data were available, only 11 survived (61%). Detailed immunophenotypic characterization and clinical features of all cases are presented. Unexpectedly, three of four cases of blastic plasmacytoid dendritic cell neoplasm tested showed focal positivity for S-100. S-100 was negative in 28 cases of acute myeloid leukemia evaluated for this marker.

Conclusions

In contrast to adult cases, in which long-term survival depends on stem cell transplantation in first complete remission, blastic plasmacytoid dendritic cell neoplasms in children are clinically less aggressive. Treatment with high-risk acute lymphoblastic leukemia-type chemotherapy appears to be effective, and stem cell transplantation may be reserved for children who relapse and achieve a second remission. Outcomes were more favorable in cases that lacked cutaneous disease at presentation, although a comparison of cutaneous and non-cutaneous cases might be confounded by differences in treatment regimens. Focal expression of S-100 may be seen in concert with other markers of plasmacytoid dendritic cells.     

Peripheral blood CD5-positive B lymphocytes (B-1a cells) after allogeneic stem cell transplantation for acute myeloid leukaemia in humans

Background

Only few data are available in literature regarding the reconstitution of B-1a cells after allogeneic bone marrow transplantation performed for haematological malignancies.

Methods

In this study we used flow cytometry to assess the reconstitution of the peripheral blood B-1a cell compartment after allogeneic peripheral blood stem cell transplantation. Cytometric analyses were performed over time on 11 consecutive patients undergoing allogeneic peripheral blood stem cell transplantation for acute myeloid leukaemia in our Haematology Unit and the results were compared with available data regarding B-1a cell reconstitution after allogeneic bone marrow stem cell transplantation.

Results

In spite of an earlier recovery of B-1a cells in the peripheral blood after allogeneic bone marrow transplantation, the reconstitution of this B-cell subset was similar, regardless of the source of stem cells employed.

Conclusions

Further studies are necessary in order to clarify the origin of B-1a cells in humans in health and illness.     

Infection with multiple viruses is not associated with increased disease severity in children with bronchiolitis

Background

The clinical relevance of parallel detection of multiple viruses by real‐time polymerase chain reaction (RT‐PCR) remains unclear. This study evaluated the association between the detection of multiple viruses by RT‐PCR and disease severity in children with bronchiolitis.

Methods

Children less than 2 years of age with clinical symptoms of bronchiolitis were prospectively included during three winter seasons. Patients were categorized in three groups based on disease severity; mild (no supportive treatment), moderate (supplemental oxygen and/or nasogastric feeding), and severe (mechanical ventilation). Multiplex RT‐PCR of 15 respiratory viruses was performed on nasopharyngeal aspirates.

Results

In total, 142 samples were obtained. Respiratory Syncytial virus (RSV) was the most commonly detected virus (73%) followed by rhinovirus (RV) (30%). In 58 samples (41%) more than one virus was detected, of which 41% was a dual infection with RSV and RV. In RSV infected children younger than 3 months, disease severity was not associated with the number of detected viruses. Remarkably, in children older than 3 months we found an association between more severe disease and RSV mono‐infections.

Conclusion

Disease severity in children with bronchiolitis is not associated with infection by multiple viruses. We conclude that other factors, such as age, contribute to disease severity to a larger extent. Pediatr Pulmonol. 2012; 47:393–400. © 2011 Wiley Periodicals, Inc.

     

Admission is not always necessary for patients with community-acquired pneumonia in risk classes IV and V diagnosed in the emergency room

OBJECTIVE:

To determine the factors that allow patients with community-acquired pneumonia who are at high risk of mortality (risk classes IV and V) to be treated at home.

DESIGN:

A prospective, observational study.

SETTING:

Six hospitals and one free-standing emergency room in Edmonton, Alberta.

PARTICIPANTS:

The present study included 2354 patients in risk classes IV and V who had a diagnosis of pneumonia made by an emergency room physician or an internist.

MEASUREMENTS:

Symptoms, signs and laboratory findings, as well as outcome measures of length of stay and mortality.

RESULTS:

Of the total study group, 319 of the patients (13.5%) were treated on an ambulatory basis. Factors predictive of admission were definite or possible pneumonia on chest radiograph as read by a radiologist, functional impairment, altered mental status, substance abuse, psychiatric disorder, abnormal white blood cell count, abnormal lymphocyte count, oxygen saturation less than 90% and antibiotic administration in the week before admission. If chest pain was present, admission was less likely. Only two of the 319 patients required subsequent admission (both had positive blood cultures) and only two died.

CONCLUSIONS:

A substantial number of patients in risk classes IV and V can be safely treated at home. Factors that help clinicians to select this subset of patients are discussed.     

Endothelial cell-derived microparticles induce plasmacytoid dendritic cell maturation: potential implications in inflammatory diseases

Background

Increased circulating endothelial microparticles, resulting from vascular endothelium dysfunction, and plasmacytoid dendritic cell activation are both encountered in common inflammatory disorders. The aim of our study was to determine whether interactions between endothelial microparticles and plasmacytoid dendritic cells could contribute to such pathologies.

Design and Methods

Microparticles generated from endothelial cell lines, platelets or activated T cells were incubated with human plasmacytoid dendritic cells sorted from healthy donor blood or with monocyte-derived dendritic cells. Dendritic cell maturation was evaluated by flow cytometry, cytokine secretion as well as naive T-cell activation and polarization. Labeled microparticles were also used to study cellular interactions.

Results

Endothelial microparticles induced plasmacytoid dendritic cell maturation. In contrast, conventional dendritic cells were resistant to endothelial microparticle-induced maturation. In addition to upregulation of co-stimulatory molecules, endothelial microparticle-matured plasmacytoid dendritic cells secreted inflammatory cytokines (interleukins 6 and 8, but no interferon-α) and also induced allogeneic naive CD4⁺ T cells to proliferate and to produce type 1 cytokines such as interferon-γ and tumor necrosis factor-α. Endothelial microparticle endocytosis by plasmacytoid dendritic cells appeared to be required for plasmacytoid dendritic cell maturation. Importantly, the ability of endothelial microparticles to induce plasmacytoid dendritic cells to mature was specific as microparticles derived from activated T cells or platelets (the major source of circulating microparticules in healthy subjects) did not induce such plasmacytoid dendritic cell maturation.

Conclusions

Our data show that endothelial microparticles specifically induce plasmacytoid dendritic cell maturation and production of inflammatory cytokines. This novel activation pathway may be implicated in various inflammatory disorders and endothelial microparticles could be an important immunmodulatory therapeutic target.     

Characterization of hospital and community‐acquired respiratory syncytial virus in children with severe lower respiratory tract infections in Ho Chi Minh City,Vietnam, 2010

Background

Human respiratory syncytial virus (RSV) is an important community and nosocomial pathogen in developed countries but data regarding the importance of RSV in developing countries are relatively scarce.

Methods

During a 1-year surveillance study in 2010, we took serial samples from children admitted to the Emergency Unit of the Respiratory Ward of Children''s Hospital 1 in Ho Chi Minh City, Vietnam. RSV was detected within 72 hours of admission to the ward in 26% (376/1439; RSV A: n = 320; RSV B: n = 54; and RSV A and B: n = 2). Among those negative in the first 72 hours after admission, 6·6% (25/377) acquired nosocomial RSV infection during hospitalization (RSV A: n = 22; and RSV B: n = 3).

Results

Children with nosocomial RSV infection were younger (P = 0·001) and had a longer duration of hospitalization (P < 0·001). The rate of incomplete recovery among children with nosocomial RSV infection was significantly higher than among those without (P < 0·001). Phylogenetic analysis of partial G gene sequences obtained from 79% (316/401) of positive specimens revealed the co-circulation of multiple genotypes with RSV A NA1 being predominant (A NA1: n = 275; A GA5: n = 5; B BA3: n = 3; B BA9: n = 26; and B BA10: n = 7). The RSV A GA5 and RSV B BA3 genotypes have not been reported from Vietnam, previously.

Conclusion

Besides emphasizing the importance of RSV as a cause of respiratory infection leading to hospitalization in young children and as a nosocomial pathogen, data from this study extend our knowledge on the genetic diversity of RSV circulating in Vietnam.     

Systemic response of peripheral blood leukocytes and their phagocytic activity during acute myocardial infarction

OBJECTIVES:

To determine changes in leukocyte counts and phagocytic activity of peripheral blood mononuclear (MN) and polymorphonuclear (PMN) cells as potential cellular markers of systemic immunological events in acute myocardial infarction (AMI).

PATIENTS AND METHODS:

Thirty patients with a first AMI and 30 healthy volunteers were examined. Immunological analyses were performed at admission and repeated at one and seven days after the acute event. MN and PMN cells were obtained from heparinized whole blood after centrifugation and separation on a density gradient, and incubated with a fixed number of heat-inactivated and labelled yeast particles. Total leukocyte counts, leukocyte populations and some parameters of phagocytic activity were determined: percentage phagocytosis, phagocytic index, absolute phagocytic index, count of phagocytes in a fixed volume of peripheral blood (CP) and phagocytic capacity.

RESULTS:

Patients with AMI had increased total leukocyte counts accompanied by increased PMN counts, while there were no significant differences in total MN count and MN populations. Except for the phagocytic index, all phagocytic parameters of MN and PMN cells were increased in patients with AMI at admission and on the first day of disease. On the seventh day after AMI only the CP of MN cells had increased significantly in patients with AMI, while percentage phagocytosis, CP and capacity of phagocytosis of PMN cells increased during the acute phase of AMI.

CONCLUSIONS:

These data suggest that AMI was followed with a strongly systemic inflammatory response to myocardial damage. Furthermore, activated MN and PMN cells may be a significant source of free radicals that may be involved in lipid peroxidation and produce tissue damage in the early postinfarction period.     

Epidemiological and clinical data of hospitalizations associated with respiratory syncytial virus infection in children under 5 years of age in Spain: FIVE multicenter study

Background

Respiratory syncytial virus (RSV) is an important pathogen in lower respiratory tract infections (LRTI) in infants, but there are limited data concerning patients with underlying conditions and children older than 2 years of age.

Methods

We have designed a prospective observational multicenter national study performed in 26 Spanish hospitals (December 2011–March 2012). Investigational cases were defined as children with underlying chronic diseases and were compared with a group of previously healthy children (proportion 1:2). Clinical data were compared between the groups.

Results

A total of 1763 children hospitalized due to RSV infection during the inclusion period were analyzed. Of them, 225 cases and 460 healthy children were enrolled in the study. Underlying diseases observed were respiratory (64%), cardiovascular (25%), and neurologic (12%), as well as chromosomal abnormalities (7·5%), immunodeficiencies (6·7%), and inborn errors of metabolism (3·5%). Cases were statistically older than previously healthy children (average age: 16·3 versus 5·5 months). Cases experienced hypoxemia more frequently (P < 0·001), but patients with respiratory diseases required oxygen therapy more often (OR: 2·99; 95% CI: 1·03–8·65). Mechanical ventilation was used more in patients with cardiac diseases (OR: 3·0; 95% CI: 1·07–8·44) and in those with inborn errors of metabolism (OR: 12·27; 95% CI: 2·11–71·47). This subgroup showed a higher risk of admission to the PICU (OR: 6·7, 95% CI: 1·18–38·04). Diagnosis of pneumonia was more frequently found in cases (18·2% versus 9·3%; P < 0·01).

Conclusions

A significant percentage of children with RSV infection have underlying diseases and the illness severity is higher than in healthy children.     

Prognostic factors for intensive care unit admission, intensive care outcome, and post-intensive care survival in patients with de novo acute myeloid leukemia: a single center experience

Background

Acute myeloid leukemia is a life-threatening disease associated with high mortality rates. A substantial number of patients require intensive care. This investigation analyzes risk factors predicting admission to the intensive care unit in patients with acute myeloid leukemia eligible for induction chemotherapy, the outcome of these patients, and prognostic factors predicting their survival.

Design and Methods

A total of 406 consecutive patients with de novo acute myeloid leukemia (15–89 years) were analyzed retrospectively. Markers recorded at the time of diagnosis included karyotype, fibrinogen, C-reactive protein, and Charlson comorbidity index. In patients requiring critical care, the value of the Simplified Acute Physiology Score II, the need for mechanical ventilation, and vasopressor support were recorded at the time of intensive care unit admission. The independent prognostic relevance of the parameters was tested by multivariate analysis.

Results

Sixty-two patients (15.3%) required intensive care, primarily due to respiratory failure (50.0%) or life-threatening bleeding (22.6%). Independent risk factors predicting intensive care unit admission were lower fibrinogen concentration, the presence of an infection, and comorbidity. The survival rate was 45%, with the Simplified Acute Physiology Score II being the only independent prognostic parameter (P<0.05). Survival was inferior in intensive care patients compared to patients not admitted to an intensive care unit. However, no difference between intensive care and non-intensive care patients was found concerning continuous complete remission at 6 years or survival at 6 years in patients who survived the first 30 days after diagnosis (non-intensive care patients: 28%; intensive care patients: 20%, P>0.05).

Conclusions

Ongoing infections, low fibrinogen and comorbidity are predictive for intensive care unit admission in acute myeloid leukemia. Although admission was a risk factor for survival, continuous complete remission and survival of patients alive at day 30 were similar in patients who were admitted or not admitted to an intensive care unit.     

Twenty-five years of epidemiological recording on myeloid malignancies: data from the specialized registry of hematologic malignancies of C?te d’Or (Burgundy,France)

Background

Epidemiological data on myeloid malignancies are very rare in the literature due to a lack of registration by cancer registries until 2000. The Registry of Hematologic Malignancies of the Côte d’Or Department in France has, however, steadfastly registered data on cases occurring in the Department since 1980, resulting, to date, in a database of over 5,000 cases classified according to the ICD-O-3 classification, following the most recent World Health Organization classification criteria.

Design and Methods

Twenty-five years of data on myeloid malignancies, including acute myeloid leukemia, myeloproliferative neoplasms, myelodysplastic syndromes and myelodysplastic/myeloproliferative syndromes were analyzed. World population standardized incidence rates were calculated as were as observed and relative survival.

Results

Incidence rates per 100,000 inhabitants/year were 2.5 for acute myeloid leukemia, 1.3 for myelodysplastic syndromes, 3.2 for myeloproliferative neoplasms and 0.6 for myelodysplastic/myeloproliferative syndromes. It was found that the incidence rate of myelodysplastic syndromes increased significantly over the period. The median overall survival is 8.9 months for patients with acute myeloid leukemia, 33.8 months for patients with myelodysplastic syndromes, 91.7 months for those with myeloproliferative neoplasms and 26.6 months for patients with myelodysplastic/myeloproliferative syndromes. Observed and relative 20-year survival rates are, respectively, 12% and 13% in acute myeloid leukemia, 2% and 6% in myelodysplastic syndromes and 20% and 34% in myeloproliferative neoplasms.

Conclusions

These population-based data on myeloid malignancies are the first data collected over such a long period and provide interesting information for clinicians and public health authorities, particularly given the paucity of other long-term, population-based data from cancer registries.     

Bronchiectasis exacerbations: The role of atypical bacteria and respiratory syncytial virus

BACKGROUND:

Aside from the known role of common bacteria, there is a paucity of data regarding the possible role of atypical bacteria and viruses in exacerbations of non-cystic fibrosis bronchiectasis.

OBJECTIVE:

To explore the possible role of atypical bacteria (namely, Mycoplasma pneumoniae and Chlamydophila pneumoniae) and respiratory syncytial virus (RSV) as causative agents of bronchiectasis exacerbations.

METHODS:

A cohort of 33 patients was studied over a two-year period (one year follow-up for each patient). Polymerase chain reaction for the detection of M pneumoniae, C pneumoniae and RSV in bronchoalveolar lavage samples were performed during all visits. Antibody titres (immunoglobulin [Ig]M and IgG) against the aforementioned pathogens were also measured. In addition, cultures for common bacteria and mycobacteria were performed from the bronchoalveolar lavage samples.

RESULTS:

Fifteen patients experienced a total of 19 exacerbations during the study period. Although RSV was detected by polymerase chain reaction during stable visits in four patients, it was never detected during an exacerbation. M pneumoniae and C pneumoniae were never detected at stable visits or during exacerbations. IgM antibody titres for these three pathogens were negative in all patient visits.

CONCLUSIONS:

Atypical pathogens and RSV did not appear to be causative agents of bronchiectasis exacerbations.     

Readmission within 30 days of Hospital Discharge among Children Receiving Chronic Dialysis

Background and objectives

The hospital admission rate for children receiving chronic dialysis has been increasing over the last decade. Approximately one third of patients with ESRD age 0–19 years are readmitted to the hospital within 30 days of discharge. The objective of this study was to examine hospital readmissions among a cohort of children receiving chronic dialysis to identify factors associated with higher rates of 30-day readmission.

Design, settings, participants, & measurements

A retrospective cohort of index admissions was developed among chronic dialysis patients age 3 months to 17 years at free-standing children’s hospitals reporting information to the Pediatric Hospital Information System between January 2006 and November 30, 2010, and followed until December 31, 2010. The primary outcome was any-cause 30-day readmission, and the secondary outcome was 30-day readmission for a cause similar to that of the index hospitalization.

Results

In this cohort, 25% of hospital admissions were followed by a readmission within 30 days. Children older than 2 years of age had a lower odds of readmission (odds ratio [OR], 0.6; 95% confidence interval [95% CI], 0.5 to 0.8). Those receiving hemodialysis had a higher risk of readmission (OR, 1.2; 95% CI, 1.0 to 1.4), and admissions >14 days were also more likely to be followed by a readmission (OR, 1.5; 95% CI, 1.1 to 2.0). Approximately 50% of the readmissions were for a similar diagnosis as the index admission; however, the specific admitting diagnosis was not associated with readmission.

Conclusions

A significant number of admissions among children receiving long-term dialysis are followed by readmission within 30 days. Further investigation is required to reduce the high rate of readmissions in these children.     

Hypocellular acute myeloid leukemia in adults: analysis of the clinical outcome of 123 patients

Background

The hypocellular variant of acute myeloid leukemia accounts for less than 10% of all cases of adult acute myeloid leukemia. It is defined by having less than 20 percent of cellular bone marrow in a biopsy at presentation. It is unclear in the literature whether the outcome of hypocellular acute myeloid leukemia differs from that of non-hypocellular acute myeloid leukemia.

Design and Methods

We retrospectively analyzed all the cases reported to be hypocellular acute myeloid leukemia between 2000 and 2009. A second pathology review was conducted and the diagnosis was confirmed in all cases.

Results

One hundred twenty-three (9%) patients were identified: patients with hypocellular acute myeloid leukemia were older than those with non-hypocellular acute myeloid leukemia (P=0.009) and more frequently presented with cytopenias (P<0.001). Forty-one patients with hypocellular acute myeloid leukemia had an antecedent hematologic disorder and 11 patients had received prior chemo-radiotherapy for non-hematopoietic neoplasms. On multivariate analysis, overall survival, remission duration and event-free survival were comparable to those of other patients with acute myeloid leukemia.

Conclusions

The outcome of hypocellular acute myeloid leukemia does not differ from that of non-hypocellular acute myeloid leukemia.