A ring-calcified thymoma, mimicking pericardial cyst, precedes pure red cell aplasia for more than 10 years - A case-based overview of pathophysiology.

Pure red cell aplasia (PRCA) is a rare disease characterised by anaemia and low reticulocyte count, caused by absence of erythropoiesis in the bone marrow. This report describes a case of a ring-calcified thymoma that led to the development of PRCA. Moreover, we provide an overview on the classification of thymoma and the pathophysiology and treatment of PRCA.

Repeated oral glucose tolerance tests in women at risk for gestational diabetes mellitus.

OBJECTIVE: Pregnant women with a negative oral glucose tolerance test (OGTT) between 24-28 weeks as part of risk-based screening for gestational diabetes mellitus (GDM) may develop clinical signs or symptoms suggestive for GDM in the third trimester. We aimed to determine the additional yield of repeating an OGTT to detect missed GDM in this group and assess patient characteristics and indications associated with a positive second OGTT. STUDY DESIGN: We conducted a retrospective cohort study of women with a negative OGTT between 24-28 weeks of pregnancy in two hospitals in the Netherlands. Patient characteristics, pregnancy outcomes, OGTT results and indications were compared between women with normal (non-GDM) and abnormal (GDM) results of the second OGTT, using the WHO 1999 criteria (fasting glucose ≥7.0 mmol/L or 2 -h post load ≥7.8 mmol/L). We used receiver operating characteristic (ROC) curve analysis to determine cut-offs for fasting and 2 -h glucose values of the index OGTT that were associated with a positive OGTT in the third trimester. RESULTS: Of 3147 women at risk for GDM, 183 underwent a second OGTT in the third trimester following their regular OGTT at 24-28 weeks. In 43 women (23.5%) GDM was diagnosed based on the second OGTT. A history of GDM was associated with subsequent GDM diagnosis, with an odds ratio of 2.6 (95% CI 1.0-6.3). Both fasting and 2 -h post load glucose values of the index OGTT were significantly higher in women with abnormal OGTT results later in pregnancy. Index OGTT glucose value cut-offs of 4.8 mmol/L (fasting) and 6.5 mmol/L (2 -h) had positive predictive values of 0.32 and 0.47 for a positive OGTT in the third trimester, and negative predictive values of 0.83 and 0.90, respectively. Fetal growth as a clinical symptom for GDM was the most frequent indication for repeating the OGTT, resulting in the diagnosis of GDM in 22.7% of women tested for this indication. CONCLUSION: Repeating an OGTT after initial negative screening results in additional GDM diagnoses. In case of clinical signs, especially in women with additional risk factors such as a history of GDM or higher index OGTT glucose values, repeating an OGTT could be considered.

Flow cytometric white blood differential using CytoDiff™ in the diagnosis of neonatal early-onset infection.

OBJECTIVE: Neonatal early-onset infection is a life-threatening disease, requiring early diagnosis and treatment. Newborns at risk are identified by a combination of risk factors, clinical signs of infection and laboratory parameters such as white blood cell count and C-reactive protein (CRP). This method is labor-intensive, time consuming and has a variable reproducibility. New reliable diagnostic markers are needed to identify neonatal infection. This study presents additional leukocyte differential parameters produced by the automated flow cytometry and processing software using CytoDiff™ reagent (Beckman Coulter) in newborns suspected for early-onset infection. METHODS: An analytic prospective observational case-control study was performed in which 185 newborns were included and retrospectively allocated into two groups, "infection likely" and "infection unlikely". Leukocyte parameters of the CytoDiff™ technique were compared with microscopic slide differentiation and routine tests. RESULTS: We showed significant lower numbers of monocytes, CD16(-) monocytes and lymphocytes (including T+/NK-lymphocytes) in neonates suspected for early-onset infection using CytoDiff™ technique. The manual counting did not demonstrate changes with respect to the number of monocytes in these neonates. CONCLUSIONS: The automated routine CytoDiff™ leukocyte differential provides an interesting additional diagnostic tool, next to routine laboratory diagnostics, in the diagnosis of neonatal early-onset infection.

No evidence for JAK2(V617F) mutation in monoclonal B cells in 2 patients with polycythaemia vera and concurrent monoclonal B cell disorder.

Occurrence of Philadelphia chromosome-negative myeloproliferative neoplasms (Ph(-) MPN) and lymphoproliferative disorders, like B cell chronic lymphocytic leukaemia (B-CLL), in the same patient is rare. JAK2(V617F) mutation was recently introduced as a powerful diagnostic tool for Ph(-) MPN. JAK2(V617F) mutation is not present in B-CLL. In 4 previously reported patients with JAK2(V617F)-positive Ph(-) MPN and B-CLL there was no definitive proof of JAK2(V617F) mutation in B-CLL cells, although this was suggested in 1 patient. We present 2 patients with JAK2(V617F)-positive polycythaemia vera who subsequently developed a monoclonal B cell disorder. The granulocytes were separated from the mononuclear cells by centrifugation on density gradient. Using an ARIA-SORP sorter, the CD20+/CD5+ B cells were separated from the CD20+/CD5- B cells, T cells, NK cells and monocytes. On each of the fractions JAK2(V617F) mutation was analysed by allele-specific competitive blocker-PCR. In both patients JAK2(V617F) mutation was present in granulocytes confirming the clinical diagnosis of polycythaemia vera. We did not detect the JAK2(V617F) mutation in the CD20+/CD5+ B cells but detected it in CD20+/CD5- B cells, T and NK cells, indicating a lymphoid subdifferentiation of the JAK2(V617F) MPN clonality. JAK2(V617F) MPN and monoclonal B cell disorder can coexist but there is no evidence that the proliferative behaviour of these B cells is mediated through the JAK2(V617F) mutation.

Granulocytosis and thrombocytosis in renal cell carcinoma: a pro-inflammatory cytokine response originating in the tumour.

BACKGROUND: In up to 20% of patients with renal cell cancer (RCC) an inflammatory response consisting of low-grade fever, weight loss and an elevated ESR and CRP may occur with modest granulocytosis and thrombocytosis. Clinical and experimental data suggest a pathogenic role for tumour-derived cytokine production, especially interleukin-6. CASE REPORT: A 79-year-old female with RCC presented with low-grade fever, weight loss and overt granulocytosis and thrombocytosis. Radiological examination revealed a right-sided renal tumour. During nephrectomy a gradient between the IL-6 levels in the renal artery and vein was demonstrated, providing direct evidence for in vivo production of IL-6 by the tumour affected kidney, which was confirmed by the demonstration of IL -6 in the tumour cells by immunohistochemical staining and in the supernatant of the homogenised tumour. Cytogenetic examination revealed complex abnormalities including a gain of chromosome 7. In addition we demonstrated production of IL-1alpha, IL-1beta, IL-8 and ICAM-1 in the tumour with systemic elevated levels of IL-6 and IL-8 with secondary increased serum G-CSF and TPO levels. CONCLUSION: We have provided direct evidence for the production of pro-inflammatory cytokines by renal cancer cells in a patient with RCC and a profound inflammatory response, with a central role of IL-6, probably due to a gain of chromosome 7. The extreme granulocytosis and thrombocytosis may have resulted from the secondary systemic production of G-CSF and TPO.

Risk factors for relapse in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis: tools for treatment decisions?

Current treatment based on the use of cyclophosphamide and corticosteroids has changed anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides from highly fatal into more chronic relapsing diseases. Relapses are a major problem in these diseases and cause increased morbidity and mortality. Current clinical research mainly focuses on achieving control of active disease while minimizing treatment-related toxicity. Risks for longterm relapse and their sequelae have been less thoroughly studied. It is noteworthy that, besides treatment, several other factors have been associated with the occurrence of relapses. Thus, compared to MPO-ANCA positive patients, patients with PR3-ANCA associated vasculitis run a significantly increased risk of experiencing relapses. ANCA-status during follow-up, levels of T cell activation, genetic background, and infectious and other exogenous factors have been linked to relapse as well. With a few exceptions, these associations are merely descriptive and not pathophysiologically proven. Furthermore, data on adapting treatment in accordance with risk factors for relapse are scarce. We review here the risk factors for relapse in ANCA-associated vasculitis, their potential pathogenic implications, and their possible role in preventive strategies and adaptations of current treatment policies.

Membrane proteinase 3 expression on resting neutrophils as a pathogenic factor in PR3-ANCA-associated vasculitis.

Antineutrophil cytoplasm autoantibody (ANCA)-associated small vessel vasculitides are systemic diseases characterized by chronic inflammation of blood vessels. These vasculitides are associated with the presence of ANCA which are, in most cases, directed towards proteinase 3 (PR3) or myeloperoxidase (MPO). In vitro and in vivo data have suggested a pathophysiological role in the ANCA-associated vasculitides, particularly based on the capacity of autoantibodies to bind and activate neutrophils. This review focuses on the role of constitutive expression of proteinase 3 on the membrane of resting neutrophils (mPR3). mPR3 can be expressed on the total population or on a subset of neutrophils and levels of mPR3 differ between individuals. The level of mPR3 on resting neutrophils and the percentage of mPR3 expressing neutrophils is stable in time for a given individual, suggesting a genetic determinant. Patients with ANCA-associated vasculitis have an increased constitutive expression of mPR3 on resting neutrophils compared to healthy controls. High levels of mPR3 on resting neutrophils are a risk factor for the development of relapses in patients with PR3-ANCA-associated vasculitis, probably by making resting neutrophils more susceptible for binding ANCA and induction of activation. As such, constitutive mPR3 expression on neutrophils seems another pathogenic factor in ANCA-associated vasculitis.