Biomarkers in Parkinson disease: studies on clinical, radiological and biological biomarkers

Parkinson disease is the second most common neurodegenerative disorder after Alzheimer disease. It affects 2 to 3 percent of those over 65 years with an age-dependent prevalence. Currently, the diagnosis of PD is hampered by the limited sensitivity and specificity of the available investigations. The diagnosis is usually made based on the clinical presentation which has a number of significant limitations. First of all, the disease has been present for decades before motor symptoms develop. Secondly, using clinical exam alone, the misdiagnosis rate remains high with both over-and under-diagnosis common. It is important to make an expeditious and correct diagnosis of PD, especially in this era of increasing interest in neuroprotective strategies for PD and other neurodegenerative conditions. Delaying the diagnosis until motor symptoms develop is suboptimal as more than 40% of dopaminergic neurons have been destroyed at this stage. We also need to ensure that true cases of PD are being enrolled in PD trials and that these trials are not being confounded by the inclusion of individuals with other causes of parkinsonism. To accomplish these goals, there is a need for PD biomarkers that are both sensitive and specific. The objective of this thesis was to investigate, using a case-control study design, a number of potential biomarkers for PD. These biomarkers included clinical, biological and radiological markers. In the first study, we investigated the role of autonomic neuropathy as a clinical biomarker for PD. Using thermal threshold testing, nerve conduction testing and questionnaires, the PD group demonstrated a higher prevalence of autonomic neuropathy. Other outcome measures, including the presence of non-motor symptoms, pain, depressive symptoms and electrophysiological evidence of large fiber neuropathy were also found to be more prevalent in the PD group. In the second and third studies, we explored the potential role of CSF biological biomarkers in PD. In the second study, we evaluated CSF cytokine levels with the aim of identifying a unique cytokine pattern in the CSF of PD subjects. We failed to detect a cytokine pattern and found no difference in cytokine levels between PD and control groups. However, within a cohort of the PD group, we identified an association between IL-2 levels and disease severity, with higher concentrations of IL-2 seen in those with more severe disease. In the third study, we measured GDF5 protein levels in the CSF and found lower concentrations of GDF5 in the PD group compared to controls. GDF5 levels were lower in the female PD subjects compared to males. There was no association between GDF5 concentrations and PD characteristics, age or cognition. In the final study, we assessed the utility of SPECT imaging of dopamine transporters in the striatal region of the brain (DaTSCAN) as a radiological biomarker for PD in our healthcare system. Following a review of scans over a five-year period, 69% of scans showed evidence of dopaminergic deficit, supporting a diagnosis of PD. Review of request forms for DaTSCAN, demonstrated inappropriate referrals in 13% of cases. Chart review in a subgroup of scans documented a change in patient management in 65% of cases, based on the result of the scan. In this thesis, we sought to identify potential biomarkers for PD. We found significant differences between the subjects with PD and controls using clinical and biological tests. We also demonstrated findings that support the utility of a radiological biomarker in clinical practice. Our studies showed promising results and require further research. In the future, we envision studies investigating a multimodal biomarker approach in large cohorts of PD subjects

The utility of dopamine transporter scans for diagnosing Parkinsonian disorders

Introduction: Dopamine transporter scans are increasingly being used in the diagnosis of clinically undefined Parkinsonism. Aims: To assess the indications for imaging usage and its impact on future clinical management. Methods: Retrospective review of scans ordered and their corresponding results over a five-year period. A chart review was carried out on a cohort of scans to assess changes in clinical management. Results: One hundred and eighty scans (69% of total) were reported as showing evidence of dopaminergic deficit. A chart review in 81 patients showed a change in clinical management in 53 patients (65%). Scans were ordered inappropriately in 34 patients (13%). Discussion: 123I-FP-CIT SPECT scans are being more frequently ordered and if used correctly can alter clinical management. Increased education on indications for use is required to reduce waste of resources and risk to patients

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Adult stem cell-derived complete lung organoid models emulate lung disease in COVID-19.

BackgroundSARS-CoV-2, the virus responsible for COVID-19, causes widespread damage in the lungs in the setting of an overzealous immune response whose origin remains unclear.MethodsWe present a scalable, propagable, personalized, cost-effective adult stem cell-derived human lung organoid model that is complete with both proximal and distal airway epithelia. Monolayers derived from adult lung organoids (ALOs), primary airway cells, or hiPSC-derived alveolar type II (AT2) pneumocytes were infected with SARS-CoV-2 to create in vitro lung models of COVID-19.ResultsInfected ALO monolayers best recapitulated the transcriptomic signatures in diverse cohorts of COVID-19 patient-derived respiratory samples. The airway (proximal) cells were critical for sustained viral infection, whereas distal alveolar differentiation (AT2→AT1) was critical for mounting the overzealous host immune response in fatal disease; ALO monolayers with well-mixed proximodistal airway components recapitulated both.ConclusionsFindings validate a human lung model of COVID-19, which can be immediately utilized to investigate COVID-19 pathogenesis and vet new therapies and vaccines.FundingThis work was supported by the National Institutes for Health (NIH) grants 1R01DK107585-01A1, 3R01DK107585-05S1 (to SD); R01-AI141630, CA100768 and CA160911 (to PG) and R01-AI 155696 (to PG, DS and SD); R00-CA151673 and R01-GM138385 (to DS), R01- HL32225 (to PT), UCOP-R00RG2642 (to SD and PG), UCOP-R01RG3780 (to P.G. and D.S) and a pilot award from the Sanford Stem Cell Clinical Center at UC San Diego Health (P.G, S.D, D.S). GDK was supported through The American Association of Immunologists Intersect Fellowship Program for Computational Scientists and Immunologists. L.C.A's salary was supported in part by the VA San Diego Healthcare System. This manuscript includes data generated at the UC San Diego Institute of Genomic Medicine (IGC) using an Illumina NovaSeq 6000 that was purchased with funding from a National Institutes of Health SIG grant (#S10 OD026929)

Adult stem cell-derived complete lung organoid models emulate lung disease in COVID-19.

SARS-CoV-2, the virus responsible for COVID-19, causes widespread damage in the lungs in the setting of an overzealous immune response whose origin remains unclear. We present a scalable, propagable, personalized, cost-effective adult stem cell-derived human lung organoid model that is complete with both proximal and distal airway epithelia. Monolayers derived from adult lung organoids (ALOs), primary airway cells, or hiPSC-derived alveolar type II (AT2) pneumocytes were infected with SARS-CoV-2 to create in vitro lung models of COVID-19. Infected ALO monolayers best recapitulated the transcriptomic signatures in diverse cohorts of COVID-19 patient-derived respiratory samples. The airway (proximal) cells were critical for sustained viral infection, whereas distal alveolar differentiation (AT2→AT1) was critical for mounting the overzealous host immune response in fatal disease; ALO monolayers with well-mixed proximodistal airway components recapitulated both. Findings validate a human lung model of COVID-19, which can be immediately utilized to investigate COVID-19 pathogenesis and vet new therapies and vaccines. This work was supported by the National Institutes for Health (NIH) grants 1R01DK107585-01A1, 3R01DK107585-05S1 (to SD); R01-AI141630, CA100768 and CA160911 (to PG) and R01-AI 155696 (to PG, DS and SD); R00-CA151673 and R01-GM138385 (to DS), R01- HL32225 (to PT), UCOP-R00RG2642 (to SD and PG), UCOP-R01RG3780 (to P.G. and D.S) and a pilot award from the Sanford Stem Cell Clinical Center at UC San Diego Health (P.G, S.D, D.S). GDK was supported through The American Association of Immunologists Intersect Fellowship Program for Computational Scientists and Immunologists. L.C.A's salary was supported in part by the VA San Diego Healthcare System. This manuscript includes data generated at the UC San Diego Institute of Genomic Medicine (IGC) using an Illumina NovaSeq 6000 that was purchased with funding from a National Institutes of Health SIG grant (#S10 OD026929)

Increased Peripheral Blood Neutrophil Activation Phenotypes and Neutrophil Extracellular Trap Formation in Critically Ill Coronavirus Disease 2019 (COVID-19) Patients: A Case Series and Review of the Literature.

BackgroundIncreased inflammation has been well defined in coronavirus disease 2019 (COVID-19), while definitive pathways driving severe forms of this disease remain uncertain. Neutrophils are known to contribute to immunopathology in infections, inflammatory diseases, and acute respiratory distress syndrome, a primary cause of morbidity and mortality in COVID-19. Changes in neutrophil function in COVID-19 may give insight into disease pathogenesis and identify therapeutic targets.MethodsBlood was obtained serially from critically ill COVID-19 patients for 11 days. Neutrophil extracellular trap formation (NETosis), oxidative burst, phagocytosis, and cytokine levels were assessed. Lung tissue was obtained immediately postmortem for immunostaining. PubMed searches for neutrophils, lung, and COVID-19 yielded 10 peer-reviewed research articles in English.ResultsElevations in neutrophil-associated cytokines interleukin 8 (IL-8) and interleukin 6, and general inflammatory cytokines IFN-inducible protien-19, granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin 1β, interleukin 10, and tumor necrosis factor, were identified both at first measurement and across hospitalization (P < .0001). COVID-19 neutrophils had exaggerated oxidative burst (P < .0001), NETosis (P < .0001), and phagocytosis (P < .0001) relative to controls. Increased NETosis correlated with leukocytosis and neutrophilia, and neutrophils and NETs were identified within airways and alveoli in lung parenchyma of 40% of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected lungs available for examination (2 of 5). While elevations in IL-8 and absolute neutrophil count correlated with disease severity, plasma IL-8 levels alone correlated with death.ConclusionsLiterature to date demonstrates compelling evidence of increased neutrophils in the circulation and lungs of COVID-19 patients. Importantly, neutrophil quantity and activation correlates with severity of disease. Similarly, our data show that circulating neutrophils in COVID-19 exhibit an activated phenotype with enhanced NETosis and oxidative burst