Pulmonary embolism (PE) is a serious and sometimes life-threatening condition that refers to a blood clot that occludes the arteries of the lung. Despite all improvements over the past decades,... Show morePulmonary embolism (PE) is a serious and sometimes life-threatening condition that refers to a blood clot that occludes the arteries of the lung. Despite all improvements over the past decades, diagnosing PE is still a difficult process due to the non-specific symptoms, which can frequently overlap with symptoms of other cardiopulmonary diseases. Currently recommended diagnostic strategies for suspected acute PE consist of standardized assessment of the clinical pre-test probability (CPTP) using validated clinical decision rules (CDRs) and D-dimer testing. PE is considered safely ruled out in patients with a non-high CPTP and a normal D-dimer test. Imaging tests as computed tomography pulmonary angiography (CTPA) are required in the case of a high CPTP and/or abnormal D-dimer test to confirm the diagnosis. The first part of this thesis describes the challenges of diagnosing PE in general and in specific clinically relevant patient subgroups. Moreover, this part evaluates the diagnostic performance of non-invasive diagnostic strategies for suspected PE in specific relevant patient subgroups. The second part of this thesis focuses on venous thrombotic complications in hospitalized patients with COVID-19. Show less
This thesis comprises immunophenotypic and molecular studies in several types of cutaneous lymphomas. These studies provide a better definition of the clinicopathologic entities and provide... Show moreThis thesis comprises immunophenotypic and molecular studies in several types of cutaneous lymphomas. These studies provide a better definition of the clinicopathologic entities and provide adjunctive diagnostic markers that may aid in diagnosis of these patients in routine diagnostics, including TOX expression in cutaneous T-cell lymphomas and MYC expression and MYC rearrangements in cutaneous B-cell lymphomas (CBCLs). Also, the results demonstrate that adverse prognostic factors in systemic lymphomas are not directly transferrable to cutaneous lymphoma patients, including TP63 rearrangements in primary cutaneous CD30+ lymphoproliferative disorders and double hit status in CBCL, underlining the importance of a separate classification system for cutaneous lymphomas. Finally, these studies may have consequences for the management and treatment of patients with cutaneous lymphomas, because of the identification of recurrent molecular alterations that could provide attractive targets for novel therapeutics, including MYD88 and CD79B mutations in patients with intravascular large B-cell lymphomas. Show less
This thesis consists of a number of studies revolving around the leading research theme, i.e., the derivation of new vectorcardiographic diagnostic & prognostic information from the 12-lead... Show moreThis thesis consists of a number of studies revolving around the leading research theme, i.e., the derivation of new vectorcardiographic diagnostic & prognostic information from the 12-lead electrocardiogram (ECG). Various research questions have been addressed, but most studies use a similar data processing approach, consisting of initial mathematical synthesis of a vectorcardiogram (VCG) from a standard 12-lead ECG, followed by the measurement of general VCG characteristics like maximal QRS- and T vectors, QRS- and T integrals, the spatial QRS-T angle (SA) and the ventricular gradient (VG). Studies focus on methodological as well as on clinical issues, and are discussed in the thesis. Show less
Distale radius fracturen komen veel voor. Bij ongeveer de helft van de distale radius fracturen komt een processus styloideus ulnae (PSU, distale ulna fractuur) voor. Een PSU fractuur is een... Show moreDistale radius fracturen komen veel voor. Bij ongeveer de helft van de distale radius fracturen komt een processus styloideus ulnae (PSU, distale ulna fractuur) voor. Een PSU fractuur is een indicator voor toegenomen instabiliteit. In een meta-analyse wordt geen verschil aangetoond in uitkomst van een distale radius fracturen met of zonder PSU fractuur. Hetzelfde geldt voor het al dan niet vastgroeien van het PSU. In ongeveer 33% van de distale radius fracturen komt distale radioulnaire (DRU) instabiliteit voor. Klinische testen en radiologische onderzoeken om dit te diagnosticeren zijn weinig betrouwbaar. Een CT-scan additioneel aan een r_ntgenfoto zorgt niet voor toename in overeenstemming over de uitslag. De overeenstemming tussen beoordelaars van CT-scans valt tegen, naast een grote normale spreiding. Wanneer DRU instabiliteit gediagnostiseerd is, zal de ossale anatomie genormaliseerd moeten worden. In dit proefschrift worden operatie-technieken beschreven die veilig en effectief zijn voor het oplossen van DRU instabiliteit. De auteur concludeert dat DRU instabiliteit een diagnostisch dilemma is. Onderzoek zal zich moeten richten op individuele normaalwaarden, zodat de diagnose makkelijker te stellen is. De aanbeveling wordt gedaan dat distale radius fracturen behandeld dienen te worden door gespecialiseerde teams zodat de complicaties beperkt blijven en indien nodig herkend en optimaal behandeld worden. Show less
Venous thromboembolism is a common disease that can lead to potential fatal complications. The diagnosis and treatment of a first venous thromboembolism has been well studied, however the... Show moreVenous thromboembolism is a common disease that can lead to potential fatal complications. The diagnosis and treatment of a first venous thromboembolism has been well studied, however the diagnostic management and therapy of recurrent venous thromboembolism still have limitations. This thesis discusses a new imaging technique for recurrent deep venous thrombosis and the duration of treatment after a recurrent venous thromboembolism. It shows that Magnetic Resonance Direct Thrombus Imaging might be a potential diagnostic tool for the diagnostic management of recurrent venous thromboembolism. Furthermore the prognosis after a first deep vein thrombosis is discussed by means of recurrence and bleeding risks. Show less
This thesis focuses on cellular immunity against mycobacteria during latency with the aim to contribute to improved immunodiagnosis of latent TB and to gain insight into immune responses which play... Show moreThis thesis focuses on cellular immunity against mycobacteria during latency with the aim to contribute to improved immunodiagnosis of latent TB and to gain insight into immune responses which play a role in controlling latent infection. Several new highly M. tuberculosis-specific peptides mixtures were identified to optimize the sensitivity of immunodiagnostic assays. The performance of interferon-gamma-release-assays (IGRA) for detection of latent TB were evaluated. Two short-incubation IGRA, QuantiFERON-TB Gold and T-SPOTTM.TB, were found to correlate better to the level of exposure to M. tuberculosis than the tuberculin skin test (TST), indicating that these assays are very sensitive for detection of recent infections. However, short-incubation IGRA are less sensitive than prolonged-incubation IGRA and TST for detection of latent TB acquired in the past. The search for proteins that are specifically targeted by the immune system during latency led to the identification of several antigens encoded within the DosR-regulon. This set of genes of M. tuberculosis is strongly upregulated by during in vitro models of latency. These antigens, including 16kDa _-crystallin, were preferentially recognized by latently infected individuals, which suggest that T-cell responses to latency antigens are associated with natural protection against reactivation of TB, warranting their further study as vaccine candidates. Show less
