Immunoglobulin G/immunoglobulin M autoantibody ratios in incomplete systemic lupus erythematosus.

OBJECTIVE: Immunoglobulin G (IgG) autoantibodies in systemic lupus erythematosus (SLE) are considered pathogenic, whereas immunoglobulin M (IgM) autoantibodies may have protective effects. The aim of this study was to identify whether IgG/IgM autoantibody ratios differ between patients with incomplete systemic lupus erythematosus (iSLE), patients with SLE, and healthy controls (HCs), and whether IgG/IgM autoantibody ratios relate to progression from iSLE to SLE. METHOD: This prospective cohort study included 34 iSLE patients, 41 SLE patients, and 11 HCs. IgG and IgM anti-dsDNA, anti-Ro52, and anti-Ro60 were measured by fluoro-enzyme immunoassay in serum samples obtained at baseline in all groups and in follow-up samples of up to 5 years for iSLE patients. Correlations between IgG/IgM autoantibody ratios, interferon signature, and clinical parameters were also assessed. RESULTS: At baseline, IgG anti-dsDNA, anti-Ro52, anti-Ro60, and IgM anti-dsDNA were elevated in iSLE and SLE patients. IgG/IgM anti-dsDNA and anti-Ro52 ratios were similar between groups, while IgG/IgM anti-Ro60 ratios were significantly elevated in iSLE and SLE patients compared to HCs. IgG/IgM autoantibody ratios were not correlated with interferon signature or clinical parameters. IgG/IgM ratios at baseline were similar and remained relatively stable during a median follow-up of 18 months in non-progressors and six iSLE patients who progressed to SLE. CONCLUSION: IgG anti-dsDNA, anti-Ro52, anti-Ro60, and IgM anti-dsDNA were elevated in iSLE and SLE patients, which was not apparent from the respective IgG/IgM ratios only. IgG/IgM autoantibody ratios remained relatively stable over up to 5 years in iSLE non-progressors and six patients who progressed to SLE.

Low body weight and involuntary weight loss are associated with Raynaud's phenomenon in both men and women.

Objectives: Low body weight is an easily assessable cause of Raynaud's phenomenon (RP), and is frequently overlooked by clinicians. We aim to investigate the association of low body weight (body mass index < 18.5 kg/m2), involuntary weight loss, and nutritional restrictions with the presence of RP.Method: Participants from the Lifelines Cohort completed a validated self-administered connective tissue disease questionnaire. Subjects who reported cold-sensitive fingers and biphasic or triphasic colour changes were considered to suffer from RP. Patient characteristics, anthropometric measurements, and nutritional habits were collected. Statistical analyses was stratified for gender.Results: Altogether, 93 935 participants completed the questionnaire. The prevalence of RP was 4.2% [95% confidence interval (CI) 4.1-4.4%], and was three-fold higher in women than in men (5.7% vs 2.1%, p < 0.001). Subjects with RP had a significantly lower daily caloric intake than those without RP. Multivariate analysis, correcting for creatinine level, daily caloric intake, and other known aetiological factors associated with RP, revealed that low body weight [men: odds ratio (OR) 5.55 (95% CI 2.82-10.93); women: 3.14 (2.40-4.10)] and involuntary weight loss [men: OR 1.32 (1.17-1.48); women: 1.31 (1.20-1.44)] were significantly associated with the presence of RP. Low-fat diet was also associated with RP in women [OR 1.27 (1.15-1.44)].Conclusion: Low body weight and prior involuntary weight loss are associated with an increased risk of RP in both men and women. This study emphasizes that low body weight and weight loss are easily overlooked risk factors for RP, and should be assessed and monitored in subjects with RP.

[Antibiotic prophylaxis and immune-compromised patients]. / AB-profylaxe en immuungecompromitteerde patiënten.

On the basis of the arguments found in the literature for and against prescribing antibiotic prophylaxis for dental procedures in immunecompromised patients, dental care providers are advised not to prescribe antibiotic prophylaxis to this group of patients when they undergo dental treatment, unless it concerns an exceptional case. Such cases comprise immune-compromised patients considered to have a high risk of developing systemic infections when undergoing invasive dental procedures, including extractions or implant placement. These are patients with, for example, severe neutropenia, patients with a primary immune deficiency, or patients who use high doses of immunosuppressants or very strong immunosuppressants. There is little evidence in the literature about the use of antibiotic prophylaxis for this specific group of patients. Such evidence is, however, also difficult to obtain because it concerns a small group of patients.

Longitudinal analysis of varicella-zoster virus-specific antibodies in systemic lupus erythematosus: No association with subclinical viral reactivations or lupus disease activity.

Systemic lupus erythematosus (SLE) patients are at high risk of herpes zoster. Previously, we found increased immunoglobulin (Ig)G levels against varicella-zoster virus (VZV) in SLE patients compared to controls, while antibody levels against diphtheria and cellular immunity to VZV were decreased. We aimed to test our hypothesis that increased VZV-IgG levels in SLE result from subclinical VZV reactivations, caused by stress because of lupus disease activity or immunosuppressive drug use. Methods Antibody levels to VZV (IgG, IgA, IgM), total IgG and VZV-DNA were longitudinally determined in the serum of 34 SLE patients, using enzyme-linked immunosorbent assay and polymerase chain reaction. Clinical data were retrieved from medical records. Reactivation of VZV was defined as an at least fivefold rise in VZV-IgG or presence of VZV-IgM or VZV-DNA. Generalized estimating equations (GEE) were used to longitudinally analyse associations between antibody levels, lupus disease activity and medication use. Systemic Lupus Erythematosus Disease Activity Index, anti-double-stranded DNA and complement levels were used as indicators of lupus disease activity. Results A VZV reactivation was determined in 11 patients (33%). In at least five of them, herpes zoster was clinically overt. No association between SLE disease activity or medication use and VZV-specific antibody levels was found. There was a weak association between total IgG and VZV-IgG. Conclusions Our results indicate that increased VZV-IgG levels in SLE do not result from frequent subclinical VZV reactivations, and are not associated with lupus disease activity. Increased VZV-IgG can only partially be explained by hypergammaglobulinaemia.

Autoantibodies to box A of high mobility group box 1 in systemic lupus erythematosus.

Autoantibodies to nuclear structures are a hallmark of systemic lupus erythematosus (SLE), including autoantibodies to nuclear protein high mobility group box 1 (HMGB1). HMGB1 consists of three separate domains: box A, box B and an acidic tail. Recombinant box A acts as a competitive antagonist for HMGB1 and might be an interesting treatment option in SLE. However, antibodies to box A might interfere. Therefore, levels of anti-box A were examined in SLE patients in association with disease activity and clinical parameters. Serum anti-box A was measured in 86 SLE patients and 44 age- and sex-matched healthy controls (HC). Serum samples of 28 patients with primary Sjögren's syndrome and 32 patients with rheumatoid arthritis were included as disease controls. Anti-HMGB1 and anti-box B levels were also measured by enzyme-linked immunosorbent assay during quiescent disease [SLE Disease Activity Index (SLEDAI) ≤ 4, n = 47] and active disease (SLEDAI ≥ 5, n = 39). Anti-box A levels in active SLE patients were higher compared to quiescent patients, and were increased significantly compared to HC and disease controls. Anti-box A levels correlated positively with SLEDAI and anti-dsDNA levels and negatively with complement C3 levels. Increased levels of anti-box A antibodies were present in the majority of patients with nephritic (73%) and non-nephritic exacerbations (71%). Antibodies to the box A domain of HMGB1 might be an interesting new biomarker, as these had a high specificity for SLE and were associated with disease activity. Longitudinal studies should be performed to evaluate whether these antibodies perform better in predicting an exacerbation, especially non-nephritic exacerbations.

Pharmacokinetics of Monoclonal Antibodies Throughout Pregnancy: A Systematic Literature Review.

BACKGROUND AND OBJECTIVE: Although little information is available on the pharmacokinetics (PK) of monoclonal antibodies (mAbs) during pregnancy, multiple mAbs are being used during pregnancy for various indications. The aim of this systematic literature review was to characterize the PK of mAbs throughout pregnancy. METHODS: A systematic literature search was carried out in PubMed and Embase on 21 April 2023. Articles were included when information on PK or exposure parameters of mAbs in pregnant women was available. RESULTS: A total of 42 relevant articles were included, of which eight discussed adalimumab, three certolizumab pegol, five eculizumab, one golimumab, 12 infliximab (IFX), two natalizumab, one canakinumab, one omalizumab, five tocilizumab, eight ustekinumab, and five vedolizumab. One of the 42 studies reported information on clearance (CL) and volume of distribution (VD) of IFX; all other studies only reported on serum concentrations in the pre-pregnancy state, different trimesters, and the postpartum period. For all of the assessed mAbs except IFX, serum concentrations were similar to concentrations in the pre-pregnancy state or modestly decreased. In contrast, IFX trough concentrations generally increased in the second and third trimesters in comparison to the non-pregnant state. CONCLUSION: Available information suggests that the anatomical and physiological changes throughout pregnancy may have meaningful effects on the PK of mAbs. For most mAbs (not IFX), modestly higher dosing (per mg) maybe needed during pregnancy to sustain a similar serum exposure compared to pre-pregnancy.

Superior mesenteric artery aneurysm in a 9-year-old boy with classical Ehlers-Danlos syndrome.

A 9-year-old boy with the classical type of Ehlers-Danlos syndrome (EDS) developed a symptomatic aneurysm of the superior mesenteric artery. His EDS diagnosis had been confirmed biochemically and genetically. Vascular complications are known to be associated with the vascular type of EDS, but this is the first report of a child with classical EDS who developed a major vascular complication. Clinicians should be aware that severe vascular complications albeit rare, can also occur in classical EDS.

[18F]Sodium Fluoride PET has the potential to identify active formation of calcinosis cutis in limited cutaneous systemic sclerosis.

OBJECTIVES: Calcinosis cutis affects 20-40% of patients with systemic sclerosis (SSc). When calcinosis cutis becomes clinically apparent, it is irreversible in most cases. Detection of active calcification formation might allow early disease-modifying interventions. We assessed the feasibility of visualizing active calcifications using [18F]Sodium Fluoride ([18F]NaF) PET/low-dose CT (LDCT) in SSc patients with calcinosis cutis. METHODS: In this cross-sectional, observational pilot study patients underwent a whole body [18F]NaF PET/LDCT. All patients met the 2013 ACR/EULAR SSc criteria and had clinically detectable calcinosis cutis. (Sub)cutaneous calcifications were described by three investigators. RESULTS: Nine female patients were included (median age 59.0 years [IQR 51.5-70.5]). [18F]NaF uptake was mostly visible in the fingers (n=7) and knees (n=5). [18F]NaF PET showed calcifications in the fingers of 3 patients where calcifications were undetected on LDCT and in the clinic. Ninety-seven percent of [18F]NaF positive lesions was visible on LDCT. Of all lesions visible on LDCT, 70% was also visible on [18F]NaF PET. CONCLUSION: Imaging of active calcifications in SSc is feasible using [18F]NaF PET/LDCT. Seventy percent of calcifications on LDCT were [18F]NaF PET positive. Although these findings require replication, [18F]NaF PET/LDCT may detect active calcification formation, being potentially suitable for early disease-modifying interventions.

Long-Term Clinical Outcomes in a Cohort of Adults With Childhood-Onset Systemic Lupus Erythematosus.

OBJECTIVE: Childhood-onset systemic lupus erythematosus (SLE) is a severe, lifelong, multisystem autoimmune disease. Long-term outcome data are limited. This study was undertaken to identify clinical characteristics and health-related quality of life (HRQoL) of adults with childhood-onset SLE. METHODS: Patients participated in a single study visit comprising a structured history and physical examination. Disease activity (scored using the SLE Disease Activity Index 2000 [SLEDAI-2K]), damage (scored using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index [SDI]), and HRQoL (scored using the Short Form 36 Health Survey) were assessed. Medical records were reviewed. RESULTS: In total, 111 childhood-onset SLE patients were included; the median disease duration was 20 years, 91% of patients were female, and 72% were white. Disease activity was low (median SLEDAI-2K score 4), and 71% of patients received prednisone, hydroxychloroquine (HCQ), and/or other disease-modifying antirheumatic drugs. The vast majority of new childhood-onset SLE-related manifestations developed within 2 years of diagnosis. Damage such as myocardial infarctions began occurring after 5 years. Most patients (62%) experienced damage, predominantly in the musculoskeletal, neuropsychiatric, and renal systems. Cerebrovascular accidents, renal transplants, replacement arthroplasties, and myocardial infarctions typically occurred at a young age (median age 20 years, 24 years, 34 years, and 39 years, respectively). Multivariate logistic regression analysis showed that damage accrual was associated with disease duration (odds ratio [OR] 1.15, P < 0.001), antiphospholipid antibody positivity (OR 3.56, P = 0.026), and hypertension (OR 3.21, P = 0.043). Current HCQ monotherapy was associated with an SDI score of 0 (OR 0.16, P = 0.009). In this cohort, HRQoL was impaired compared to the overall Dutch population. The presence of damage reduced HRQoL scores in 1 domain. High disease activity (SLEDAI-2K score ≥8) and changes in physical appearance strongly reduced HRQoL scores (in 4 of 8 domains and 7 of 8 domains, respectively). CONCLUSION: The majority of adults with childhood-onset SLE in this large cohort developed significant damage at a young age and had impaired HRQoL without achieving drug-free remission, illustrating the substantial impact of childhood-onset SLE on future life.

Diagnosing and treating antiphospholipid syndrome: a consensus paper.

INTRODUCTION: The antiphospholipid syndrome (APS) is defined by the occurrence of venous and/or arterial thrombosis and/or pregnancy-related morbidity, combined with the presence of antiphospholipid antibodies (aPL) and/or a lupus anticoagulant (LAC). Large, controlled, intervention trials in APS are limited. This paper aims to provide clinicians with an expert consensus on the management of APS. METHODS: Relevant papers were identified by literature search. Statements on diagnostics and treatment were extracted. During two consensus meetings, statements were discussed, followed by a Delphi procedure. Subsequently, a final paper was written. RESULTS: Diagnosis of APS includes the combination of thrombotic events and presence of aPL. Risk stratification on an individual base remains challenging. 'Triple positive' patients have highest risk of recurrent thrombosis. aPL titres > 99th percentile should be considered positive. No gold standard exists for aPL testing; guidance on assay characteristics as formulated by the International Society on Thrombosis and Haemostasis should be followed. Treatment with vitamin K-antagonists (VKA) with INR 2.0-3.0 is first-line treatment for a first or recurrent APS-related venous thrombotic event. Patients with first arterial thrombosis should be treated with clopidogrel or VKA with target INR 2.0-3.0. Treatment with direct oral anticoagulants is not recommended. Patients with catastrophic APS, recurrent thrombotic events or recurrent pregnancy morbidity should be referred to an expert centre. CONCLUSION: This consensus paper fills the gap between evidence-based medicine and daily clinical practice for the care of APS patients.

Skin autofluorescence is increased in systemic lupus erythematosus but is not reflected by elevated plasma levels of advanced glycation endproducts.

OBJECTIVES: To examine whether skin advanced glycation endproducts (AGEs) accumulation, plasma levels of AGEs-N(epsilon)-carboxymethyllysine (CML) and N(epsilon)-carboxyethyllysine (CEL)-and serum levels of soluble receptor for AGEs (sRAGE) are elevated in SLE patients compared with controls, and whether these parameters are related to disease activity and endothelial cell (EC) activation. METHODS: Ten SLE patients (9 women, age 34 +/- 13 yrs, mean +/- s.d.) and 10 age- and sex-matched controls were included. Patients were analysed during inactive as well as active disease. Skin AGE accumulation was estimated using ultraviolet-A (UV-A) light for measurement of autofluorescence obtained by Excitation-Emission matrix Scanner (AF-EEMS). Levels of CML and CEL were determined by tandem mass spectrometry. Levels of sRAGE and of soluble vascular cell adhesion molecule-1 (sVCAM-1) were determined by ELISAs. RESULTS: Skin AF-EEMS was increased in SLE patients compared with controls (P < 0.05). Levels of CML and CEL were comparable between patients and controls and were not influenced by disease activity. sRAGE and sVCAM-1 levels were higher in quiescent SLE patients compared with controls (P < 0.05) and increased further during active disease (P < 0.05). In patients with quiescent disease and controls, sRAGE levels correlated to sVCAM-1 levels (r = 0.579, P = 0.007). CONCLUSIONS: Skin AGEs and levels of sRAGE and sVCAM-1 were elevated in SLE patients, whereas levels of CML and CEL were comparable with controls. As sRAGE even further increased during endothelial activation, it might be hypothesized that sRAGE acts as a decoy receptor. Why this proposed mechanism is insufficient to prevent increased AGE accumulation in the skin of SLE patients has to be established.

Skin capillary permeability in the diabetic foot with critical limb ischaemia: the effects of a phVEGF165 gene product.

AIMS: To measure capillary permeability, assessed by skin capillary sodium fluorescein (NaF) leakage, in patients with diabetes mellitus with critical limb ischaemia (DM-CLI) and to compare the effects of vascular endothelial growth factor (VEGF) with those of placebo. METHODS: NaF leakage was assessed in 17 patients with DM-CLI, in 24 diabetes mellitus (DM) patients without clinical signs of macrovascular disease or neuropathy (DM-C) and in 22 healthy control subjects. The 17 DM-CLI patients were randomized to receive phVEGF165 gene product (n = 11) or placebo (n = 6). Measurements were repeated after 28 days. RESULTS: DM-CLI patients had a longer dye arrival time (DAT), but NaF leakage was similar to control subjects, while capillary permeability was increased in DM-C compared with control subjects. Leakage curve rose in patients receiving VEGF and fell in those receiving placebo, 28 days after administration. The decrease in DAT in the VEGF group was not significant, whilst DAT rose in the placebo group. Perfusion pressures were similar in the two groups. CONCLUSION: No increase in capillary leakage in DM-CLI was found, probably because an increased capillary filtration coefficient is counterbalanced by a marked fall in perfusion pressures. Increased capillary leakage may be one explanation for oedema formation after VEGF treatment.

Effect and mechanism of hydrocortisone on organ function in patients with severe burns.

INTRODUCTION: In patients with severe burns, resuscitation with large volumes of fluid is needed, partly because of an increase in capillary leakage. Corticosteroids might be beneficial by diminishing capillary leakage. This study aimed to assess in severely burned nonseptic patients whether hydrocortisone (HC) improved outcome and diminished capillary leakage. METHODS: Retrospective analyses of a prospectively collected database were performed, including 39 patients (age 52 [35-62] years, 72% male). Patients were divided based on HC therapy. First, in patients in whom HC was started late, that is when deteriorating (late; 5-12 days postburn) data before and after start of HC were compared. Second, patients in whom HC was started day 0 or 1 postburn (upfront; within 48 hours) were compared with patients who did not receive HC (control). Outcome was assessed as organ dysfunction by Denver Multiple Organ Failure (MOF) score and Sequential Organ Failure Assessment (SOFA) score. As markers for capillary leakage and hydration state, proteinuria, B-type natriuretic peptide (BNP), and fluid administration were assessed. Follow-up was 20 days postburn. Possible adverse effects including mortality were recorded. Repeated measurement regression analyses were performed using MLwiN. RESULTS: In the late group, Denver MOF and SOFA scores significantly decreased after HC (P<.001). Proteinuria tended to decrease (P=.13), BNP increased on the days HC was used (P<.001), and amounts of fluids diminished (P<.001). In the upfront vs control group, Denver MOF and SOFA scores (P<.001) decreased more quickly. Proteinuria (P=.006) and administered fluids decreased more rapidly (P<.001). Mortality rate, numbers of positive blood cultures, incidence of pneumonia, and graft loss were similar in all groups. CONCLUSIONS: Hydrocortisone treatment in severe burned patients without sepsis might improve organ dysfunction possibly because of a reduction in capillary leakage, as reflected by a decrease of proteinuria, an increase of BNP, and diminished fluid resuscitation volumes.

Clinical modulation of multidrug resistance in multiple myeloma: effect of cyclosporine on resistant tumor cells.

PURPOSE: In multiple myeloma (MM) refractory to doxorubicin (DXR) and/or vincristine (VCR), myeloma cells frequently express the multidrug resistance (MDR) phenotype, associated with overexpression of P-glycoprotein (Pgp), which acts as a drug efflux pump. Recently, studies have shown that clinical resistance can be modulated by drug resistance modifiers. The present study was performed to investigate if MDR modulation in vivo is caused by a direct effect of cyclosporine (CSA) on resistant myeloma plasma cells (PC). PATIENTS AND METHODS: Eight patients with VAD-refractory MM were treated with DXR, VCR, and dexamethasone (VAD) plus CSA. Pgp expression in PC was determined by flow cytometry/immunocytochemistry before and after clinical treatment. Functional Pgp expression was determined by the effect of CSA on the intracellular accumulation of DXR and VCR. RESULTS: Five of eight patients responded to VAD/CSA. The percentage of Pgp-positive (Pgp+) PC was 30% to 100% (median, 90%) before treatment and 4 to 90% (median, 40%) after treatment. CD56+/- or CD38+/- PC had identical Pgp expression. CSA, as well as SDZ PSC 833, but not dexamethasone, increased pretreatment intracellular accumulation of DXR and VCR in Pgp+ PC in three of four and six of six patients, respectively. After clinical treatment, in vitro drug accumulation in residual Pgp-negative (Pgp-) PC of four of four responding patients was not further modulated by CSA or SDZ PSC 833. At later relapse, PC of two of four patients remained Pgp-. CONCLUSION: These data indicate that Pgp overexpression is functional in refractory myeloma and that clinical modulation of MDR by CSA is mediated through an inhibition of Pgp-associated drug efflux. Pgp-expressing PC can be eliminated by clinical treatment with VAD/CSA.

A phase I and pharmacologic study of the MDR converter GF120918 in combination with doxorubicin in patients with advanced solid tumors.

BACKGROUND: Resistance to chemotherapy can partly be explained by the activity of membrane bound P-glycoprotein. Competitive inhibition of P-glycoprotein, by multidrug resistance (MDR) converters, may overcome this MDR. Previously studied MDR converters either have serious intrinsic side effects or considerably influence the pharmacokinetics of cytotoxic agents at concentrations theoretically required to convert MDR. GF120918 is a third-generation MDR converter with high affinity for P-glycoprotein and can be given orally. We performed a phase 1 study with escalating doses of GF120918 in combination with doxorubicin. PATIENTS AND METHODS: The study group comprised 46 patients with advanced solid tumors. Doxorubicin was administered on day 1 (cycle 1), GF120918 on days 22-24 (cycle 2), and on days 29-33 with doxorubicin administered on day 31 (cycle 3). Pharmacokinetics of both GF120918 and doxorubicin were studied. The starting daily dose of GF120918 was 50 mg and was to be increased in subsequent cohorts until a steady state plasma level of 100 ng/ml was reached. The starting dose of doxorubicin was 50 mg/m2 and was to be increased after reaching the target dose level of GF120918. RESULTS: In 37 of the 46 patients, full pharmacokinetic data from the three scheduled cycles were obtained. Pharmacokinetics of GF120918 showed a less than linear increase in Cmax with increasing doses, with considerable interpatient variation. The target steady-state plasma level for GF120918 was exceeded in 12 out of 19 patients who received 400 mg GF120918 alone twice daily and in 12 of 17 patients who received 400 mg GF120918 twice daily in combination with doxorubicin. GF120918 pharmacokinetics were not influenced by coadministration of doxorubicin. The doxorubicin AUC was only marginally influenced by GF120918 and only at the highest dose levels. In these patients there was a significant increase in the AUC of doxorubicinol in cycle 3 as compared to cycle 1. Hematologic toxicity mainly consisted of neutropenia and was more severe in cycle 3 than in cycle 1 (13 vs 5 patients with grade 4 neutropenia, P=0.003). Neutropenic fever was the dose-limiting toxicity at a doxorubicin dose of 75 mg/m2 with 400 mg GF120918 twice daily. The toxicity of GF120918 was limited to somnolence in eight patients and occasional gastrointestinal complaints. CONCLUSION: GF120918 is an MDR converter with only minimal side effects at a dose level yielding concentrations able to convert the action of P-glycoprotein in vitro. A doxorubicin dose of 60 mg/m2 on day 3 in combination with 400 mg GF120918 twice daily on days 1-5 is an acceptable regimen for further clinical trials.

High expression of the multidrug resistance P-glycoprotein in high-risk myelodysplasia is associated with immature phenotype.

The expression of the multidrug resistance (MDR-1) gene product, P-170 glycoprotein (P-170) was investigated in 26 patients with low-risk (n = 9) or high-risk (n = 17) myelodysplastic syndrome (MDS), using a panel of monoclonal antibodies to P-170 (C219, JSB1, C494, MRK16) and quantitative analysis of MDR-1 mRNA. P-170 membrane staining was demonstrated in bone marrow blast cells of 14/17 HR-MDS and in 2/9 LR-MDS patients (p < 0.01). P-170 expression was associated with the presence of blast cells characterized by an immature or early myeloid phenotype as defined by CD34 expression (p = 0.034), CD13 or CD33 expression (p = 0.0006), or CD13/33 plus terminal deoxynucleotidyl transferase (TdT) double expression (p = 0.04). With double fluorescence analysis, P-170 expression was observed in a subset of CD34+ cells, but not in CD34- cells. P-170 expression was present in 13/15 (86%) patient samples with an abnormal karyotype as compared with 3/10 samples (30%) with a normal karyotype (p < 0.05). Nine of these 15 patients had a loss or a deletion of chromosome 7. Thirteen out of 16 (81%) MDR-1 positive patients developed acute leukemia versus two of ten (20%) MDR-1 negative patients (p = 0.025). It is concluded that MDR-1 expression in MDS is present in cells with an immature phenotype and is frequently observed in patients who have an abnormal karyotype and a high risk of leukemic transformation.

Additional value of positron emission tomography in diagnosis and follow-up of patients with large vessel vasculitides.

OBJECTIVES: To determine the value of Positron Emission Tomography (PET) in the diagnosis of Takayasu arteritis (TA) and giant cell arteritis (GCA) and its value in the assessment of disease activity and response to therapy. METHODS: In 5 consecutive patients diagnosed with TA or GCA, PET using the tracer F18-deoxyglucose (FDG) was performed when disease activity was suspected based on clinical and laboratory parameters. PET was repeated after therapeutic intervention when disease remission was achieved. PET findings were compared with angiography, MRA and clinical parameters. RESULTS: PET visualised inflamed arteries in all 5 patients, but there was a discrepancy between PET and angiography or MRA. In 8 arteries of 4 patients only PET showed disease involvement, while in 5 arteries of 2 patients only angiography or MRA showed involvement. After treatment and the disappearance of clinical symptoms, FDG uptake was clearly reduced compared to the initial scan in all patients. In all but one the acute phase response declined. In that patient a urinary tract infection explained the elevated acute phase response, as this normalised after antibiotic treatment. CONCLUSION: PET is a promising new technique for the diagnosis of large vessel vasculitides. Furthermore, PET appears to be a valuable tool for the assessment of disease activity during follow-up and of the response to therapy.

Phagocytic plasma cells in a patient with multiple myeloma.

Phagocytosis of blood cells by malignant plasma cells in multiple myeloma is an extremely rare condition. Here we present a 39-year-old woman with multiple myeloma. Bone marrow smear showed an extensive phagocytosis of erythrocytes and platelets by myeloma cells.

"Acute liver failure": the heart may be the matter.

Hypoxic hepatitis secondary to heart failure is a known and treatable cause of liver failure. The diagnosis may be difficult, especially when symptoms of heart failure are absent. We present two patients who were transferred to our hospital with the diagnosis of acute liver failure to be screened for a liver transplantation. Both patients had increased serum levels ofaminotransferases, lactic acidosis, coagulation disorders, and non-specific clinical symptoms. Echocardiography revealed right ventricular dysfunction. Treatment with inotropes resulted in a fast normalization of liver enzymes, acidosis and coagulation, confirming the diagnosis hypoxic hepatitis. In conclusion, when the cause of acute liver dysfunction is unclear, hypoxic hepatitis due to heart failure should be considered and echocardiography should be performed, even when symptoms are non-specific for heart failure.

Vascular responsiveness in the microcirculation of patients with systemic lupus erythematosus is not impaired.

As endothelial dysfunction is one of the earliest signs of atherosclerosis, which is accelerated in systemic lupus erythematosus (SLE), we assessed whether vascular responses of the cutaneous microcirculation are disturbed in SLE patients and influenced by Raynaud's phenomenon (RP). Laser Doppler fluxmetry (LDF) was used in combination with iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), an endothelium-dependent and endothelium-independent vasodilator respectively. 42 SLE patients with inactive disease, 12 of whom had RP and 19 age- and sex-matched controls were included. Furthermore, traditional and non-traditional risk factors for cardiovascular disease (CVD) were assessed, and markers of inflammation and endothelial activation were measured. Vascular responses of SLE patients without RP did not differ from controls. However, SLE patients with RP exhibited decreased vasodilatation compared with controls. SLE patients with RP also had longer arrival times of ACh and SNP than controls. Markers of inflammation and von Willebrand factor were increased in SLE patients. Smoking, the presence of SLE and RP were negatively associated with vascular responses in univariate analysis. In multivariate analyses, the only independent variable of vascular responses to ACh and SNP was the presence of RP. Despite signs of endothelial activation, SLE patients with inactive disease do not have altered vascular responses in the microcirculation compared with controls. In SLE patients with RP, cutaneous vascular responses to both ACh and SNP are impaired. Therefore, LDF of the microcirculation seems not to be the appropriate method to distinguish those SLE patients with an increased risk to develop CVD.