The interpretation of pulmonary function tests (PFTs) to diagnose respiratory diseases is built on expert opinion that relies on the recognition of patterns and the clinical context for detection of specific diseases. In this study, we aimed to explore the accuracy and interrater variability of pulmonologists when interpreting PFTs compared with artificial intelligence (AI)-based software that was developed and validated in more than 1500 historical patient cases.120 pulmonologists from 16 European hospitals evaluated 50 cases with PFT and clinical information, resulting in 6000 independent interpretations. The AI software examined the same data. American Thoracic Society/European Respiratory Society guidelines were used as the gold standard for PFT pattern interpretation. The gold standard for diagnosis was derived from clinical history, PFT and all additional tests.The pattern recognition of PFTs by pulmonologists (senior 73%, junior 27%) matched the guidelines in 74.4±5.9% of the cases (range 56–88%). The interrater variability of κ=0.67 pointed to a common agreement. Pulmonologists made correct diagnoses in 44.6±8.7% of the cases (range 24–62%) with a large interrater variability (κ=0.35). The AI-based software perfectly matched the PFT pattern interpretations (100%) and assigned a correct diagnosis in 82% of all cases (p<0.0001 for both measures).The interpretation of PFTs by pulmonologists leads to marked variations and errors. AI-based software provides more accurate interpretations and may serve as a powerful decision support tool to improve clinical practice.

Coronavirus disease 2019 (Covid-19), caused by SARS-CoV-2, exerts far-reaching effects on public health and socioeconomic welfare. The majority of infected individuals have mild to moderate symptoms but a significant proportion develops respiratory failure due to pneumonia. Thrombosis is another frequent manifestation of Covid-19 that contributes to poor outcomes. Vitamin K plays a crucial role in activation of both pro- and anticlotting factors in the liver, and the activation of extrahepatically synthesised protein S which seems to be important in local thrombosis prevention. However, the role of vitamin K extends beyond coagulation. Matrix Gla protein (MGP) is a vitamin K-dependent inhibitor of soft tissue calcification and elastic fibre degradation. Severe extrahepatic vitamin K insufficiency was recently demonstrated in Covid-19 patients, with high inactive MGP levels correlating with elastic fibre degradation rates. This suggests that insufficient vitamin K-dependent MGP activation leaves elastic fibres unprotected against SARS-CoV-2 induced proteolysis. In contrast to MGP, Covid-19 patients have normal levels of activated factor II, in line with previous observations that vitamin K is preferentially transported to the liver for activation of procoagulant factors. We therefore expect that vitamin K-dependent endothelial protein S activation is also compromised, which would be compatible with enhanced thrombogenicity. Taking these data together, we propose a mechanism of pneumonia-induced vitamin K depletion, leading to a decrease in activated MGP and protein S, aggravating pulmonary damage and coagulopathy, respectively. Intervention trials should be conducted to assess whether vitamin K administration plays a role in prevention and treatment of severe Covid-19.

Elastin degradation is accelerated in chronic obstructive pulmonary disease (COPD) and is partially regulated by Matrix Gla Protein (MGP), via a vitamin K-dependent pathway. The aim was to assess vitamin K status in COPD as well as associations between vitamin K status, elastin degradation, lung function parameters and mortality. A total of 192 COPD patients and 186 age-matched controls were included. In addition to this, 290 COPD patients from a second independent longitudinal cohort were also included. Vitamin K status was assessed by measuring plasma inactive MGP levels and rates of elastin degradation by measuring plasma desmosine levels. Reduced vitamin K status was found in COPD patients compared to smoking controls (p < 0.0005) and controls who had never smoked (p = 0.001). Vitamin K status was inversely associated with desmosine (cohort 1: p = 0.001; cohort 2: p = 0.004). Only few significant associations between vitamin K status and lung function parameters were found. Mortality was higher in COPD patients within the quartile with the lowest vitamin K status compared to those within the other quartiles (hazard ratio 1.85, 95% confidence interval (CI), 1.21–2.83, p = 0.005). In conclusion, we demonstrated reduced vitamin K status in COPD and an inverse association between vitamin K status and elastin degradation rate. Our results therefore suggest a potential role of vitamin K in COPD pathogenesis.

The hypercoagulable state observed in COVID-19 could be responsible for morbidity and mortality. In this retrospective study we investigated whether therapeutic anticoagulation prior to infection has a beneficial effect in hospitalized COVID-19 patients. This study included 1154 COVID-19 patients admitted to 6 hospitals in the Netherlands between March and May 2020. We applied 1:3 propensity score matching to evaluate the association between prior therapeutic anticoagulation use and clinical outcome, with in hospital mortality as primary endpoint. In total, 190 (16%) patients used therapeutic anticoagulation prior to admission. In the propensity score matched analyses, we observed no associations between prior use of therapeutic anticoagulation and overall mortality (risk ratio 1.02 [95% confidence interval; 0.80-1.30]) or length of hospital stay (7.0 [4-12] vs. 7.0 [4-12] days, P = .69), although we observed a lower risk of pulmonary embolism (0.19 [0.05-0.80]).

The hypercoagulable state observed in COVID-19 could be responsible for morbidity and mortality. In this retrospective study we investigated whether therapeutic anticoagulation prior to infection has a beneficial effect in hospitalized COVID-19 patients. 1154 COVID-19 patients admitted to 6 hospitals in the Netherlands between March and May 2020 were included. We applied 1:3 propensity score matching to evaluate the association between prior therapeutic anticoagulation use and clinical outcome, with in hospital mortality as primary endpoint. 190 (16%) patients used therapeutic anticoagulation prior to admission. In the propensity score matched analyses, we observed no associations between prior use of therapeutic anticoagulation and overall mortality (RR 1.02 (95% CI; 0.80-1.30) or length of hospital stay (7.0 [4-12] vs 7.0 {4-12] days, p=0.69), although we observed a lower risk of pulmonary embolism (RR 0.19 (95% CI; 0.05-0.80). This study shows that prior use of therapeutic anticoagulation is not associated with improved clinical outcome in hospitalized COVID-19 patients.

Objective: It is suggested that patients with constipation should be screened for celiac disease. Similarly, it is recommended to investigate these patients for hypothyroidism and hypercalcemia. However, no evidence for these recommendations is available so far. We therefore set out to determine the prevalence of celiac disease, hypothyroidism, and hypercalcemia in children with constipation.Methods: Prospective cohort study of 370 consecutive patients who met the Rome III criteria for constipation. These patients were referred by a general practitioner to a pediatrician because of failure of laxative treatment.Results: Seven of these patients had biopsy-proven celiac disease. This is significantly higher (p < 0.001) than the 1:198 prevalence of celiac disease in the Netherlands. Two patients had auto-immune thyroiditis. No patient had hypercalcemia. Conclusions:We conclude that celiac disease is significantly overrepresented in patients with constipation who are referred by a general practitioner to a pediatrician because of failure of laxative treatment. All such patients should, therefore, be screened for celiac disease.J Pediatr (Rio J). 2012;88(2):173-6: Celiac disease, constipation, hypothyroidism, hypercalcemia. ResumoObjetivo: Tem sido sugerido que pacientes com constipação sejam triados para doença celíaca. Da mesma forma, recomenda-se a investigação desses pacientes para hipotiroidismo e hipercalcemia. Contudo, nenhuma evidência para essas recomendações está disponível até o momento. Assim, propusemos-nos determinar a prevalência de doença celíaca, hipotiroidismo e hipercalcemia em crianças com constipação.Métodos: Estudo de coorte prospectivo com 370 pacientes consecutivos que preencheram os critérios de Roma III para constipação. Esses pacientes foram encaminhados por um clínico geral a um pediatra devido ao fracasso no tratamento com laxantes.Resultados: A biópsia comprovou doença celíaca em sete desses pacientes. Isso é significativamente mais alto (p < 0,001) do que a prevalência de 1:198 de doença celíaca nos Países Baixos. Dois pacientes tinham tiroidite autoimune. Nenhum paciente tinha hipercalcemia. Conclusões:Conclui-se que a doença celíaca é significativamente super-representada em pacientes com constipação encaminhados por um clínico geral a um pediatra devido ao fracasso no tratamento com laxantes. Todos esses pacientes devem, portanto, ser triados para doença celíaca.

Cardiovascular diseases are prevalent in patients with chronic obstructive pulmonary disease (COPD). Their coexistence implies that many COPD patients require anticoagulation therapy. Although more and more replaced by direct oral anticoagulants, vitamin K antagonists (VKAs) are still widely used. VKAs induce profound deficiency of vitamin K, a key activator in the coagulation pathway. It is recognized however that vitamin K is also an essential cofactor in the activation of other extrahepatic proteins, such as matrix Gla protein (MGP), a potent inhibitor of arterial calcification. No or insufficient MGP activation by the use of VKAs is associated with a rapid progression of vascular calcification, which may enhance the risk for overt cardiovascular disease. Vitamin K consumption, on the other hand, seems to have a protective effect on the mineralization of arteries. Furthermore, vascular calcification mutually relates to elastin degradation, which is accelerated in patients with COPD associating with impaired survival. In this commentary, we hypothesize that vitamin K is a critical determinant to the rate of elastin degradation. We speculate on the potential link between poor vitamin K status and crucial mechanisms of COPD pathogenesis and raise concerns about the use of VKAs in patients with this disease. Future intervention studies are needed to explore if vitamin K supplementation is able to reduce elastin degradation and vascular calcification in COPD patients.

SARS-CoV-2 causes remarkably variable disease from asymptomatic individuals to respiratory insufficiency and coagulopathy. Vitamin K deficiency was recently found to associate with clinical outcome in a cohort of COVID-19 patients. Vitamin D has been hypothesized to reduce disease susceptibility by modulating inflammation, yet little is known about its role in disease severity. Considering the critical interaction between vitamin K and vitamin D in calcium and elastic fiber metabolism, we determined vitamin D status in the same cohort of 135 hospitalized COVID-19 patients by measuring blood 25(OH)D levels. We found no difference in vitamin D status between those with good and poor outcome (defined as intubation and/or death). Instead, we found vitamin D sufficient persons (25(OH)D >50 nmol/L) had accelerated elastic fiber degradation compared to those with mild deficiency (25(OH)D 25-50 nmol/L). Based on these findings, we hypothesize that vitamin D might have both favorable anti-inflammatory and unfavorable pro-calcification effects during COVID-19 and that vitamin K might compensate for the latter.