Prevalence of latent tuberculosis infection in health care workers in Poland assessed by interferon-gamma whole blood and tuberculin skin tests

Health care workers (HCWs) are at risk for developing active tuberculosis (TB). The prevalence of latent tuberculosis infection (LTBI) in this group is unknown in Poland, due largely to the problems associated with the interpretation of the tuberculin skin test (TST) in BCG immunized population. The goal of the present study was to assess the prevalence of LTBI in both clinical and non-clinical 155 HCWs (120 females and 35 males) and to compare the groups at different levels of risk. All participants were interviewed using a questionnaire and underwent interferon-gamma whole blood assay (Quantiferon-Tb-Gold) (QTF) and TST. The questionnaire provided information on possible risk factors for LTBI, including demographic and socioeconomic details, the presence of BCG scars, and the degree of occupational exposure. We found that the prevalence of LTBI among HCWs was, on average, 27.1%. A higher risk of acquiring LTBI was associated with certain work locations (TB lab workers--prevalence 50%, TB ward clinicians--34%, nurses--30%). The prevalence in analytical lab technicians was 20%, in administration staff was 15%. The HCWs with positive QTF test results were older and worked longer than those who had negative results. There was a significant correlation between the level of IFN-gamma and both age (P<0.001) and length of employment (P<0.01). The correlation between the diameter of skin test induration and the magnitude of the INF-gamma response also was significant (P<0.001). We conclude that HCWs are at increased risk of infection, suggesting that appropriate preventive strategies should be undertaken. IFN-gamma test is a useful tool in detecting LTBI cases in a country where BCG vaccination is a national policy.

Prevalence, severity and underdiagnosis of COPD in the primary care setting

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common disease with a steadily increasing prevalence and mortality. However, recent epidemiological estimates differ depending on the population studied and methods used.

AIM

To investigate the prevalence, severity and burden of COPD in a primary care setting.

METHODS

From 4730 patients registered in a single primary care practice, all 2250 patients aged 40 years or more were invited to participate. Participants completed a questionnaire on smoking, respiratory symptoms, education and social status. A physical examination was followed by pre- and post-bronchodilator (BD) spirometry.

RESULTS

Of the eligible patients, 1960 (87%) participated. 92% of spirometric tests met the ATS criteria. Airflow limitation was demonstrated in 299 (15%) of the participants pre-BD and in 211 (11%) post-BD. COPD was diagnosed in 183 patients (9.3%). Of these patients, the degree of post-BD airflow limitation was mild in 30.6%, moderate in 51.4%, severe in 15.3% and very severe in 2.7%. Only 18.6% of these patients had previously been diagnosed with COPD; almost all of these had severe or very severe airflow limitation. As a result of the study, a diagnosis of asthma was made in 122 patients.

CONCLUSIONS

The prevalence and underdiagnosis of COPD in adult patients in this primary care setting made case finding worthwhile. Large numbers of newly detected patients were symptomatic and needed treatment. Limiting investigations to smokers would have reduced the number of COPD diagnoses by 26%.

Dendritic cells in autologous hematopoietic stem cell transplantation for diffuse large B-cell lymphoma: graft content and post transplant recovery predict survival

Allograft dendritic cell (DC) content has been identified as a predictor of relapse and event-free survival after allogeneic bone marrow transplantation. However, the prognostic importance of DCs has not been evaluated in the setting of autologous hematopoietic stem cell transplantation (HSCT). We prospectively determined pre-transplant and post transplant DC levels, including DC1 and DC2 subset levels, in 53 patients with diffuse large B-cell non-Hodgkin's lymphoma (DLBC NHL) undergoing autologous HSCT. Pre-transplant DCs were measured in the collected stem cell products and were therefore indicative of cell numbers infused directly into patients; post transplant analysis of DCs was performed on the peripheral blood of patients 6 weeks after the infusion of autologous stem cells. Higher pre-transplant levels of DC1 cells and total DCs were significantly associated with improved survival. Similarly, greater post transplant levels of total DCs and both subsets were significantly associated with survival. These findings suggest a relationship between DC reconstitution and survival following autologous HSCT for DLBC NHL. Strategies to increase autograft DC content or accelerate DC recovery after autologous HSCT might improve outcomes in this setting.

Characterization of an antisense transcript spanning the UL81-82 locus of human cytomegalovirus

In this study we present the characterization of a novel transcript, UL81-82ast, UL81-82 antisense transcript, and its protein product. The transcript was initially found in a cDNA library of monocytes from a seropositive donor. mRNA was obtained from monocytes isolated from a healthy donor with a high antibody titer against human cytomegalovirus (HCMV). The mRNAs were cloned into a lambda phage-derived vector to create the cDNA library. Using PCR, UL81-82ast was amplified from the library. The library was tested for the presence of numerous HCMV genes. Neither structural genes nor immediate-early genes were found. UL81-82ast was detected in five bone marrow samples from healthy antibody-positive donors. This same transcript was also found in in vitro-infected human fibroblasts early after infection but disappears at the same time that UL82 transcription begins. Not only was the transcript amplified using reverse transcription-PCR and sequenced but its protein product (UL82as protein) was detected by both Western blot and immunofluorescence. Phylogenetic studies using UL82as protein were conducted, showing a high degree of conservation in clinical isolates, laboratory strains of HCMV, and even in chimpanzee CMV. The transcript could be involved in the posttranscriptional regulation of the UL82 gene, affecting its mRNA stability or translation. Since the UL82 product, pp71, functions as an immediate-early transactivator, its posttranscriptional control could have some effect over latency reactivation and lytic replication.

Intracellular cytokines of peripheral blood lymphocytes in nephrotic syndrome

Idiopathic nephrotic syndrome (NS) is probably caused by abnormalities in T-lymphocyte function. The presence of several immunological abnormalities in these patients supports this hypothesis, but to date there is no agreement about immunological status and its influence on the course of NS. Thirty-six children with NS [19 with first episode (group I) and 17 in remission (>6 months) of NS (group II), aged 4-17 years, mean 7.1 years] were included in the study. Nineteen age-matched healthy children constituted the control group. Anti-cytokine antibodies were used in conjunction with antibodies against cell surface antigens to study cytokine synthesis in different lymphocyte populations. In the present study the intracellular synthesis of interleukin-2 (IL-2), interferon-gamma (IFN-gamma), IL-4, and IL-6 was measured. The intracellular synthesis of IL-2 was higher in group I compared with the controls, both in the whole population of T-lymphocytes (12.1+/-6.2% vs. 7.6+/-6.7%, P=0.0281) and in the subpopulation of CD8- lymphocytes (17.3+/-8.5% vs. 7.2+/-4.8%, P=0.0001). No significant differences in IFN-gamma intracellular expression were found. The intracellular synthesis of IL-4 was lower in group I compared with the controls, both in the whole population of T-lymphocytes (1.98+/-1.92% vs. 3.6+/-3.3%, P=0.012) and in the subpopulation of CD8- lymphocytes (2.4+/-2.3% vs. 6.5+/-6.4%, P=0.0002). Similarly, the intracellular expression of IL-6 was lower in group I compared with the control group, in the whole population of T-lymphocytes (0.85+/-0.6% vs. 2.2+/-3.1%, P=0.004), in the CD8- subpopulation (1.1+/-1.1% vs. 2.2+/-2.0%, P=0.006), and in the CD8+ subpopulation (1.1+/-0.9% vs. 2.8+/-3.4%, P=0.0008). The results of this study indicate that the acute episode of NS is associated with increased intracellular synthesis of IL-2 and decreased intracellular synthesis of IL-4 and IL-6.

The application of electron microscopic morphometry as helpful method in the diagnosis of focal segmental glomerulosclerosis (FSGS) early phase. I. Morphometric electron microscopic studies of renal glomeruli in cases of focal segmental glomerulosclerosis (FSGS), minimal change disease (MCD) and mesangioproliferative glomerulonephritis (GNMES) in children

Electron microscopy morphometric studies were carried out on material obtained from children with minimal change disease (MCD), mesangioproliferative glomerulonephritis (GNMES) and focal segmental glomerulosclerosis (FSGS). The results indicated that an increase in the volume of the matrix in mesangioproliferative glomerulonephritis was due to an increase in the number of cells. The amount of produced matrix in mesangioproliferative glomerulonephritis was proportional to the number of cells in mesangium (so there is no overproduction of matrix). The ratios of mesangial matrix volume to cell volume and matrix volume to the volume of the entire mesangial region in MCD and GNMES were similar and differed significantly from the ratios found in FSGS. The present findings indicate that morphometric studies may be useful in the early diagnosis of glomerular sclerosis. This is particularly significant in cases where light microscopic examination fails to reveal changes indicative of glomerular sclerosis.

The application of electron microscopic morphometry as a helpful method in the diagnosis of focal segmental glomerulosclerosis (FSGS) early phase. II. Clinical usefulness of electron microscopic morphometric studies in cases of minimal change disease (MCD) and mesangioproliferative glomerulonephritis (GNMES) with suspicion of progression into focal segmental glomerulosclerosis (FSGS)

Clinical and morphological analysis (including morphometric studies of electron microscopic material) was made in 15 children with MCD and 15 children with GNMES. In both groups, an early phase of FSGS was suspected on the basis of electron microscopic studies. Moreover, analysis included the results obtained in 13 children with the diagnosis of FSGS and in whom repeated biopsies were performed. In most of them, MCD or GNMES was diagnosed from the first biopsy. In most children in whom electron microscopic studies revealed an increase in matrix area in some mesangial regions, thereby suggesting an early stage of glomerular sclerosis, the results of morphometric studies resembled or were identical to the results obtained from a control group with the established diagnosis of FSGS. These findings indicate that morphometric studies of electron microscopic material are significant. The results, when compared with the clinical data, confirm the usefulness of such a diagnostic procedure.

[Electrolyte abnormalities and ventricular arrhythmias in children with mitral valve prolapse]

The aim of this study was to determine plasma concentration of magnesium, potassium, calcium and sodium in children with mitral valve prolapse (MVP) and to establish the relation between electrolyte abnormalities and ventricular arrhythmias (VA). The study group consists of the 113 children with MVP (age +/- SD: 10.7 +/- 4.3 years). The 101 healthy children (age +/- SD: 13.0 +/- 3.2 years) were enrolled into the control group. All patients underwent clinical examination, standard ECG, 24 hr ECG Holter monitoring and echocardiography. Blood samples were taken 3 times in fasting state in separate days. All patients were in sinus rhythm. Cardiac arrhythmias were observed more frequently in children with MVP (53%) than in control group (31%, p < 0.0008). VA were recorded in 39% MVP patients, compared with 13% of the healthy children (p < 0.0001). There were no differences in K, Na and Ca concentrations in children with MVP comparing to control group. Serum Mg concentration was significantly lower in MVP group (0.88 +/- 0.08 mmol/l) comparing to healthy children (0.91 +/- 0.07 mmol/l, p < 0.002). A marked decrease in Mg concentration was recorded in patients with MVP and ventricular arrhythmias compared with those without ventricular arrhythmias (0.83 +/- 0.07 vs 0.90 +/- 0.06 mmol/l, p < 0.0001). This study demonstrates that potentially serious dysrhythmias are common in pediatric patients with MVP. It would appear that ambulatory ECG monitoring should be part of the complete evaluation of children with MVP. Since decreased plasma concentration, magnesium supplementation seems to be a prudent approach in children MVP with frequent ventricular premature beats and in children with ventricular tachycardia.

Telomere length dynamics in normal individuals and in patients with hematopoietic stem cell-associated disorders

The telomere length in nucleated peripheral blood (PB) cells indirectly reflects the mitotic history of their precursors: the hematopoietic stem cells (HSCs). The average length of telomeres in PB leukocytes can be measured using fluorescence in situ hybridization and flow cytometry (flow FISH). We previously used flow FISH to characterize the age-related turnover of HSCs in healthy individuals. In this review, we describe results of recent flow FISH studies in patients with selected hematopoietic stem cell-associated disorders: chronic myelogenous leukemia (CML) and several bone marrow failure syndromes. CML is characterized by a marked expansion of myeloid Philadelphia chromosome positive (Ph+) cells. Nevertheless, nonmalignant (Ph-) HSCs typically coexist in the bone marrow of CML patients. We analyzed the telomere length in > 150 peripheral blood leukocytes (PBLs) and bone marrow samples of patients with CML as well as samples of Ph- T-lymphocytes. Compared to normal controls, the overall telomere fluorescence in PBLs of patients with CML was significantly reduced. However, no telomere shortening was observed in Ph- T-lymphocytes. Patients in late chronic phase (CP) had significantly shorter telomeres than those assessed earlier in CP. Our data suggest that progressive telomere shortening is correlated with disease progression in CML. Within the group of patients with bone marrow failure syndromes, we only found significantly shortened telomeres (compared to age-adjusted controls) in granulocytes from patients with aplastic anemia (AA). Strikingly, the telomere length in granulocytes from AA patients who had recovered after immunosuppressive therapy (recAA) did not differ significantly from controls, whereas untreated patients and nonresponders with persistent severe pancytopenia (sAANR) showed marked and significant telomere shortening compared to healthy donors and patients with recAA. Furthermore, an inverse correlation between age-adjusted telomere length and peripheral blood counts was found in support of a model in which the degree of cytopenia and the amount of telomere shortening are correlated. These results support the concept of extensive proliferation of HSCs in subgroups of AA patients and suggest a potential use of telomere-length measurements as a prognostic tool in this group of disorders as well.

[Multiple bone fractures as a rare complication in a child with chronic renal failure]

Renal osteodystrophy may present with a wide spectrum of bone lesions, ranging from high bone turnover to low bone turnover. The authors present a case of multiple bone fracture in 12 year old boy with chronic renal failure. This boy was hospitalized because of retention of urea. The limping was observed by admision. In the X-rays of the long bones the multiple fracture were detected. The potential causes of these fractures and diagnostic problems were discussed.

[Dietary antioxidants and total antioxidant status in children with nephrotic syndrome]

Several studies indicate the pathophysiological importance of reactive oxygen species in patients with nephrotic syndrome (NS). The present study was designed to determine the effect of dietary antioxidants on antioxidant enzymes (SOD, GPX, GR) activity and on total antioxidant status (TAS) in children with nephrotic syndrome. 36 children with NS (19 with first episode and 17 with relapse of NS) aged 4-16 were included into the study. Total antioxidant status was estimated using two-reagent Randox Total Antioxidant Status test in plasma. All patients had normal blood pressure, normal serum creatinine level and ingested a diet appropriate for age (with individual differences). Total antioxidant status was estimated using two-reagent Randox Total Antioxidant Status test in the plasma. Glutathione peroxidase (GPX), superperoxide dysmutase (SOD) and glutathione reductase (GR) activity was using antioxidant kits (Randox). A 3-day dietary intake record was obtained from each patient and then analyzed with computer program FOOD 2.0. Laboratory investigations were performed before steroid treatment.

RESULTS

1) in children with NS TAS was significantly reduced comparing to controls (0.84 +/- 0.14, 1.21 +/- 0.62 mmol/l, p = 0.002), 2) low manganese intake was found to have negative influence on TAS (TAS = 0.38 + 14.252*Mn, p > 0.001). 3) low intake of all components of antioxidant system was found: zinc (5.6 +/- 3.5 mg/kg b.w./24 h vs 8.6 +/- 4.0 mg/kg b.w./24 h), copper (0.021 +/- 0.013 mg/kg b.w./24 h vs 0.044 +/- 0.014 mg/kg b.w./24 h), manganese (0.029 +/- 0.0021 mg/kg b.w./24 h vs. 0.067 +/- 0.023 mg/kg b.w./24 h), vitamin E (0.15 +/- 0.04 mg/kg b.w./24 h vs 0.26 +/- 0.06 mg/kg b.w./24 h) and vitamin C (0.34 +/- 0.17 mg/kg b.w./24 h vs 0.87 +/- 0.19 mg/kg b.w./24 h).

CONCLUSION

In children with NS reduced antioxidant protection maybe partly associated with low intake of some vital components of the antioxidant system.

Protease inhibitors stimulate hematopoiesis and decrease apoptosis and ICE expression in CD34(+) cells

Highly active retroviral therapy has been associated with a decline in the frequency of cytopenia in patients with human immunodeficiency virus (HIV) infection. This may result from lower hematologic toxicity of newer antiviral drugs and their increased efficacy against HIV-1. Protease inhibitors, in addition to their effects on HIV replication, appear to affect various cellular functions. Recently, it was reported that ritonavir inhibited caspase-1 expression in normal CD4(+) cells. It was hypothesized that protease inhibitors may improve hematopoietic function owing to their direct effects on the bone marrow progenitor cells. When ritonavir was added to methylcellulose cultures of bone marrow cells from HIV-infected patients and normal controls, colony formation increased 2.4-fold (n = 5) in control cultures and 4-fold (n = 5) in cultures of cells from HIV-infected patients. In the presence of ritonavir, cultures of CD34(+) cells showed markedly decreased apoptosis in comparison with untreated cultures (45% decrease in apoptotic cell number; n = 6). A synthetic inhibitor of caspase 1 (Ac-Tyr-Val-Ala-Asp-aldehyde [single-letter amino acid codes]), which inhibits activation of several caspases including CPP32 and interleukin 1beta-converting enzyme (ICE or caspase 1), also decreased the rate of apoptosis and enhanced colony formation by progenitor cells derived from HIV-infected patients (3-fold; n = 5). In ritonavir-treated samples derived from HIV-infected individuals, the number of cells expressing ICE also decreased. In conclusion, HIV protease inhibitors may, by blocking the caspase-dependent apoptotic pathway, overcome inhibition of hematopoiesis seen in patients with HIV infection, an effect unrelated to their antiviral activity. (Blood. 2000;96:2735-2739)

Th1/Th2 balance and CD45-positive T cell subsets in primary nephrotic syndrome

T cells are involved in the pathogenesis of nephrotic syndrome (NS). The aim of the study was to determine whether the activity of T-helper-1 (Th1) and T-helper-2 (Th2) cells and the distribution of the lymphocyte subsets, namely CD45RA+CD4+ ("naive" helper T cells, suppressor-inducer), CD45RA+CD8+ ("naive" suppressor T cells, suppressor-effector), CD45RO+CD4+ ("memory" helper T cells), are predictive for steroid sensitivity in children with primary NS. These parameters were assessed at the onset of disease, before initiation of steroid therapy. Two groups of NS children were retrospectively formed according to steroid sensitivity (SS) or resistance (SR). The activity of Th1 and Th2 cells was defined by the production of interleukin-2 (IL-2), interferon-gamma, IL-4, and IL-10 in the supernatants of CD4+ T cell cultures activated with autologous monocytes presenting tetanus toxoid (TT). Peripheral lymphocyte subsets were determined using double- or triple-color flow cytometry. In SS children with NS we found a decreased proliferative response of CD4+ T cells to TT stimulation, cytokine synthesis indicating the predominance of Th2 activity, and an increased percentage of activated suppressor-inducer (CD45RA+ CD4+CD25+, 5.18+/-0.8, P<0.001) and suppressor-effector (CD45RA+CD8+CD25+, 2.05+/-0.6, P<0.01) cells, with the concomitant reduction of activated memory cells (CD45RO+CD4+CD25+, 0.2+/-0.1, P<0.001). In children with SRNS we found an increased proliferative response of CD4+ T cells to TT, a rise in activated memory (CD45RO+CD4+CD25+, 3.82+/-0.7, P<0.01) and suppressor-inducer peripheral T cells (CD45RA+ CD4+CD25+, 3.85+/-0.6, P<0.01), but a low percentage of activated suppressor-effector (CD45RA+CD8+ CD25+, 0.5+/-0.2, P<0.05) T cells. We conclude that prior to treatment the distribution of lymphocyte subpopulations in peripheral blood together with Th1 and Th2 cell activity provides a useful tool for evaluating the likelihood of steroid sensitivity in patients with primary NS.