Home monitoring of coronavirus disease 2019 patients in different phases of disease.

PURPOSE OF REVIEW: Various home monitoring programs have emerged through the COVID-19 pandemic in different phases of COVID-19 disease. RECENT FINDINGS: The prehospital monitoring of COVID-19-positive patients detects early deterioration. Hospital care at home provides early discharge with oxygen to empty hospital beds for other patients. Home monitoring during recovery can be used for rehabilitation and detection of potential relapses. General goals of home monitoring in COVID-19 are early detection of deterioration and prompt escalation of care such as emergency department presentation, medical advice, medication prescription and mental support. Due to the innovations of vaccination and treatment changes, such as dexamethasone and tocilizumab, the challenge for the healthcare system has shifted from large numbers of admitted COVID-19 patients to lower numbers of admitted patients with specific risk profiles (such as immunocompromised). This also changes the field of home monitoring in COVID-19. Efficacy and cost-effectiveness of home monitoring interventions depend on the costs of the intervention (use of devices, apps and medical staff) and the proposed patient group (depending on risk factors and disease severity). SUMMARY: Patient satisfaction of COVID-19 home monitoring programs was mostly high. Home monitoring programs for COVID-19 should be ready to be re-escalated in case of a new global pandemic.

Improved Survival of IPF patients Treated With Antifibrotic Drugs Compared With Untreated Patients.

PURPOSE: Pirfenidone and nintedanib unequivocally inhibit FVC decline, but have been inconsistently linked to reduced mortality in phase III studies. On the contrary, real-world data show a survival benefit of antifibrotic drugs. However, it is unknown what this benefit is across different Gender, Age, and Physiology (GAP) stages. RESEARCH QUESTIONS: Is there a difference in transplant-free (TPF) survival of IPF patients receiving antifibrotic drugs (IPFAF) compared with an untreated cohort (IPFnon-AF)? Is this different for patients with GAP stage I, II, or III. METHODS: This is a single-center observational cohort study using prospectively included patients diagnosed with IPF between 2008-2018. Primary outcomes were TPF survival difference and 1-, 2-, and 3-year cumulative mortality for IPFAF and IPFnon-AF. This was repeated after stratification for GAP stage. RESULTS: In total, 457 patients were included. The median transplant-free survival was 3.4 years in IPFAF (n = 313) and 2.2 years in IPFnon-AF (n = 144, p = 0.005). For GAP stage II, a median survival of 3.1 and 1.7 years was noted for IPFAF (n = 143) and IPFnon-AF (n = 59, p < 0.001), respectively. A significantly lower 1-, 2-, and 3- year cumulative mortality was found for IPFAF with GAP stage II (1 yr: 7.0% vs 35.6%, 2 yr: 26.6% vs 55.9%, and 3 yr: 46.9% vs 69.5%). The 1-year cumulative mortality of IPFAF with GAP III was also significantly lower (19.0% vs 65.0%). CONCLUSION: This large real-world study showed a survival benefit in IPFAF compared with IPFnon-AF. This especially holds true for patients with GAP stage II and III.

Hit-hard and early versus step-up treatment in severe sarcoidosis.

PURPOSE OF REVIEW: The treatment of sarcoidosis remains uncertain, despite 70 years of study. The conventional approach is to initiate corticosteroids in individuals who require treatment. The position of more aggressive regimes is unknown. RECENT FINDINGS: Recent recognition that many patients will require prolonged therapy, and the observation that corticosteroids lead to overt and insidious toxicities, have led to suggestions that steroid-sparing medications be used earlier in the management of sarcoidosis. Individuals with poor prognostic features, designated as 'high-risk' sarcoidosis may, especially benefit from a broader palette of therapeutic options in the initial treatment regimen. An even more aggressive approach, known as 'top-down' or 'hit-hard and early' therapy has emerged in the fields of gastroenterology and rheumatology in the past 15 years, on the premise that highly effective early control of inflammation leads to better outcomes. These regimens typically involve early initiation of biologic therapies. SUMMARY: For certain subpopulations of sarcoidosis patients, 'top-down' therapy could be helpful. Severe pulmonary sarcoidosis, neurosarcoidosis, cardiac sarcoidosis and multiorgan sarcoidosis are phenotypes that may be most relevant for revised therapeutic algorithms. Precision medicine approaches and randomized trials will be necessary to confirm a role for top-down therapy in the routine management of sarcoidosis.

Severe pulmonary toxicity associated with inhalation of pyrethroid-based domestic insecticides (Bop/Sapolio): a case series and literature review.

PURPOSE OF REVIEW: The current review focuses on serious pulmonary toxicity after inhalation of over the counter available pyrethroid-based insecticides. Pyrethroid is a synthetic product of pyrethrin, which in turn is the active ingredient of pyrethrum, a flower extract. RECENT FINDINGS: On the contrary, a large gap of knowledge exists in the association of interstitial lung disease (ILD) with pyrethroids. So far, two cases of ILD, one associated with pyrethrin and one associated with pyrethrum, were described. Existing literature on both other (pulmo)toxic effects of pyrethroids in human and animals is summarized. SUMMARY: We present three cases of severe pulmonary toxicity after inhalation of pyrethroid-based insecticides demanding hospitalization and oxygen therapy. One of these cases died. Although a causal relationship was hard to establish, these cases all demonstrated an obvious history of (repeated) pyrethroid exposure associated with ILD. Moreover, other causes of ILD as well as infections were excluded. Furthermore, studies in mammals as well as aquatic animals confirm (pulmonary) toxicity of pyrethroids. The occurrence of toxicity is dose-dependent but also associated with individual susceptibility. Therefore, we would like to acknowledge that awareness of potential hazards of commercially available insecticides containing pyrethroids to both medical physicians and the public is mandatory.

Unfavourable outcome of glucocorticoid treatment in suspected idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: The diagnostic classification of 'possible idiopathic pulmonary fibrosis (posIPF)' is characterized by a radiological pattern of inconsistent usual interstitial pneumonia (UIP) on high-resolution computed tomography (HRCT) scan and a UIP pattern in surgical lung biopsy (SLB). The evidence base to guide treatment for patients with posIPF is lacking; the clinician must choose between observation, treatment with immunomodulatory agents or anti-fibrotic agents. METHODS: To evaluate outcomes of immunomodulatory treatment, a multicentre cohort of 59 posIPF patients treated with prednisone was analysed retrospectively. Prednisone starting dose was 0.5 mg/kg/day and tapered to 0.15 mg/day/kg over 6 months. Outcome measures were forced vital capacity (FVC) and serious adverse events (SAE), defined as death or hospital admissions. RESULTS: The majority of prednisone-treated posIPF patients were non-responders (68%) with a decrease in FVC >5% or death within 6 months from baseline; 90% of patients with radiographical presence of honeycombing were non-responders. In contrast, six out of seven patients with focal desquamative interstitial pneumonia-like reaction in the SLB who had stopped smoking for <5 years ago were responders to prednisone, demonstrating <5% FVC decline. The mean decline of FVC was 8.7% (95% CI: 3.1-14.3%) before treatment and 20% (95% CI: 9.4-31.1%) after treatment (P = 0.018) in the 32 patients with available FVC data. Twelve SAE occurred within the first 3 months on prednisone (at dosage >0.3 mg/kg/day), including five deaths. CONCLUSION: Patients with posIPF demonstrated an accelerated FVC decline and a substantial number of SAE on steroid therapy.

Effectiveness of infliximab in refractory FDG PET-positive sarcoidosis.

Inconclusive evidence for the efficacy of infliximab in sarcoidosis hinders the global use of this potentially beneficial drug. To study infliximab efficacy in a clinical setting, we performed a prospective open-label trial in patients refractory to conventional treatment. Patients (n=56) received eight infusions of 5 mg·kg(-1) infliximab. Pulmonary function, disease activity measured by (18)F-fluorodeoxyglucose (FDG) by positron emission tomography (PET) and quality of life were part of the clinical work-up. Infliximab levels were measured before every infusion. After 26 weeks of infliximab treatment, mean improvement in forced vital capacity (FVC) was 6.6% predicted (p=0.0007), whereas in the 6 months before start of treatment, lung function decreased. Maximum standardised uptake value (SUVmax) of pulmonary parenchyma on (18)F-FDG PET decreased by 3.93 (p<0.0001). High SUVmax of pulmonary parenchyma at baseline predicted FVC improvement (R=0.62, p=0.0004). An overall beneficial response was seen in 79% of patients and a partial response was seen in 17% of patients. No correlation between infliximab trough level (mean 18.0 µg·mL(-1)) and initial response was found. In conclusion, infliximab causes significant improvement in FVC in refractory (18)F-FDG PET positive sarcoidosis. Especially in pulmonary disease, high (18)F-FDG PET SUVmax values at treatment initiation predict clinically relevant lung function improvement. These results suggest that inclusion of (18)F-FDG PET is useful in therapeutic decision-making in complex sarcoidosis.

Prediction of relapse after discontinuation of infliximab therapy in severe sarcoidosis.

Infliximab is effective as a third-line therapeutic for severe sarcoidosis; however, long-term efficacy is unknown. The aim of this study was to assess the relapse rate after discontinuation of infliximab in sarcoidosis patients and predict relapse by analysis of the activity marker soluble interleukin (IL)-2 receptor (sIL-2R) and maximum standardised uptake value (SUVmax) of (18)F-fluorodeoxyglucose positron emission tomography (FDG PET). In this retrospective cohort study, the proportion of relapse was analysed using the Kaplan-Meier method and predicting factors were studied using Cox regression. 47 sarcoidosis patients who started infliximab therapy were included in the risk analysis. Kaplan-Meier analysis revealed a median time to relapse of 11.1 months and showed that 25% of the cohort relapsed within 4 months. Both mediastinal SUVmax ≥ 6.0 on FDG PET (hazard ratio 3.77, p<0.001) and serum sIL-2R ≥ 4000 pg · mL(-1) (hazard ratio 2.24, p=0.033) at start of therapy predicted relapse. In multivariate analysis, a mediastinal SUVmax ≥ 6.0 at initiation of therapy was an independent predictor of relapse (hazard ratio 4.33, p<0.001). The majority of patients that discontinued infliximab therapy relapsed. High serum sIL-2R and high SUVmax on FDG PET at initiation of therapy were significant predictors of relapse. These results suggest close monitoring of patients in this category when they discontinue infliximab treatment.

Cytotoxic agents in sarcoidosis: which one should we choose?

PURPOSE OF REVIEW: Sarcoidosis is a granulomatous disease which affects multiple organs. Its therapeutic management is very challenging due to the heterogeneity in disease manifestation and clinical course, as well as the potential side effects of the immunosuppressive therapy. An overview of presently available second-line and third-line systemic agents is provided. RECENT FINDINGS: Because curative treatment is currently not available for sarcoidosis, nonspecific immunosuppression with prednisone remains the first-choice therapy. However, as chronic use of corticosteroids is accompanied with severe adverse events, timely implementation of appropriate steroid-sparing cytotoxic agents is important. Commonly prescribed second-line agents in sarcoidosis are methotrexate, azathioprine, leflunomide and hydroxychloroquine. Nevertheless, the evidence supporting their use is limited. Third-line treatment options, including tumor necrosis factor-alpha inhibitors infliximab and adalimumab and the experimental therapeutic rituximab, are currently reserved for patients refractory to standard therapy. SUMMARY: A better insight into the advantages and disadvantages of second-line and third-line treatment is important. The long-term effects of immunosuppressive agents, the optimal starting and maintenance dosages, and the best interval and discontinuation regimens should be elucidated. Identified associations of polymorphisms with treatment response suggest a step towards personalized medicine. Future research should focus on the role for pharmacogenetic and phenotypic predictors of treatment response and toxicity.

Prevalence and clinical associations of myositis antibodies in a large cohort of interstitial lung diseases.

BACKGROUND: Serologic testing for autoantibodies is recommended in interstitial lung diseases (ILDs), as connective tissue diseases (CTDs) are an important secondary cause. Myositis antibodies are associated with CTD-ILD, but clinical associations with other ILDs are unclear. In this study, associations of myositis antibodies in various ILDs were evaluated. METHODS: 1463 ILD patients and 116 healthy subjects were screened for myositis antibodies with a line-blot assay on serum available at time of diagnosis. Additionally, bronchoalveolar lavage fluid (BALf) was analysed. RESULTS: A total of 394 patients demonstrated reactivity to at least one antibody, including anti-Ro52 (36.0%), anti-Mi-2ß (17.3%) and anti-Jo-1 (10.9%). Anti-Jo-1 (OR 6.4; p<0.100) and anti-Ro52 (OR 6.0; p<0.001) were associated with CTD-ILD. Interestingly, anti-Mi-2ß was associated with idiopathic pulmonary fibrosis (IPF; OR 5.3; p = 0.001) and hypersensitivity pneumonitis (HP; OR 5.9; p<0.001). Furthermore, anti-Mi-2ß was strongly associated with a histological usual interstitial pneumonia (UIP) pattern (OR 6.5; p < 0.001). Moreover, anti-Mi-2ß reactivity was identified in BALf and correlated with serum anti-Mi-2ß (r = 0.64; p = 0.002). No differences were found in survival rates between ILD patients with and without serum Mi-2ß reactivity (hazard ratio 0.835; 95% CI 0.442-1.575; p = 0.577). CONCLUSION: In conclusion, novel associations of antibody Mi-2ß with fibrotic ILD were found. Furthermore, serum anti-Mi-2ß was associated with a histological UIP pattern and presence of anti-Mi-2ß in BALf. Possibly, anti-Mi-2ß could be implemented as a future diagnostic biomarker for fibrotic ILD.

Switching to an Infliximab Biosimilar Was Safe and Effective in Dutch Sarcoidosis Patients.

The effect of switching from originator infliximab to biosimilar infliximab in patients with sarcoidosis is unknown. The objective of this study is to investigate the effect of switching from Remicade® or Inflectra® to Flixabi® in patients with severe refractory sarcoidosis. This single center retrospective cohort study was performed at St Antonius Hospital Nieuwegein, The Netherlands. All patients diagnosed with severe refractory sarcoidosis receiving Remicade® or Inflectra® switched to Flixabi®. The primary outcome was infliximab discontinuation within 6 months of switching. Secondary endpoints included adverse events and loss of clinical, functional, or inflammatory response. Out of 86 patients who switched to Flixabi®, 79 patients had complete data. None of the 79 patients discontinued infliximab during the first 6 months after switching. Five patients reported an adverse event related to Flixabi® treatment. We found no change from baseline in FVC, FEV1, DLCOc, 6MWT, and infliximab trough levels 26 weeks after switching. An improvement in physical functioning of 7.3 ± 13.4 points (p = 0.002) with RAND/SF36 and in biomarker sIL-2R (-475.58 ± 1452.39; p = 0.005) was observed. Switching from originator infliximab Remicade® or biosimilar infliximab Inflectra® to biosimilar infliximab Flixabi® did not result in treatment discontinuation or loss of clinical/functional/inflammatory remission.

Biomarkers in the Diagnosis and Prognosis of Sarcoidosis: Current Use and Future Prospects.

Sarcoidosis is a heterogeneous disease in terms of presentation, duration, and severity. Due to this heterogeneity, it is difficult to align treatment decisions. Biomarkers have proved to be useful for the diagnosis and prognosis of many diseases, and over the years, many biomarkers have been proposed to facilitate diagnosis, prognosis, and treatment decisions. Unfortunately, the ideal biomarker for sarcoidosis has not yet been discovered. The most commonly used biomarkers are serum and bronchoalveolar lavage biomarkers, but these lack the necessary specificity and sensitivity. In sarcoidosis, therefore, a combination of these biomarkers is often used to establish a proper diagnosis or detect possible progression. Other potential biomarkers include imaging tools and cell signaling pathways. Fluor-18-deoxyglucose positron emission tomography and high-resolution computed tomography have been proven to be more sensitive for the diagnosis and prognosis of both pulmonary and cardiac sarcoidosis than the serum biomarkers ACE and sIL-2R. There is an upcoming role for exploration of signaling pathways in sarcoidosis pathogenesis. The JAK/STAT and mTOR pathways in particular have been investigated because of their role in granuloma formation. The activation of these signaling pathways also proved to be a specific biomarker for the prognosis of sarcoidosis. Furthermore, both imaging and cell signaling biomarkers also enable patients who might benefit from a particular type of treatment to be distinguished from those who will not. In conclusion, the diagnostic and prognostic path of sarcoidosis involves many different types of existing and new biomarker. Research addressing biomarkers and disease pathology is ongoing in order to find the ideal sensitive and specific biomarker for this disease.

Prevalence of Novel Myositis Autoantibodies in a Large Cohort of Patients with Interstitial Lung Disease.

Connective tissue diseases (CTDs) are an important secondary cause of interstitial lung disease (ILD). If a CTD is suspected, clinicians are recommended to perform autoantibody testing, including for myositis autoantibodies. In this study, the prevalence and clinical associations of novel myositis autoantibodies in ILD are presented. A total of 1194 patients with ILD and 116 healthy subjects were tested for antibodies specific for Ks, Ha, Zoα, and cN1A with a line-blot assay on serum available at the time of diagnosis. Autoantibodies were demonstrated in 63 (5.3%) patients and one (0.9%) healthy control (p = 0.035). Autoantibodies were found more frequently in females (p = 0.042) and patients without a histological and/or radiological usual interstitial pneumonia (UIP; p = 0.010) and a trend towards CTD-ILDs (8.4%) was seen compared with other ILDs (4.9%; p = 0.090). The prevalence of antibodies specific for Ks, Ha, Zoα, and cN1A was, respectively, 1.3%, 2.0%, 1.4%, and 0.9% in ILD. Anti-Ha and Anti-Ks were observed in males with unclassifiable idiopathic interstitial pneumonia (unclassifiable IIP), hypersensitivity pneumonitis (HP), and various CTD-ILDs, whereas anti-cN1A was seen in females with antisynthetase syndrome (ASS), HP, and idiopathic pulmonary fibrosis (IPF). Anti-Zoα was associated with CTD-ILD (OR 2.5; 95%CI 1.11-5.61; p = 0.027). In conclusion, a relatively high prevalence of previously unknown myositis autoantibodies was found in a large cohort of various ILDs. Our results contribute to the awareness that circulating autoantibodies can be found in ILDs with or without established CTD. Whether these antibodies have to be added to the standard set of autoantibodies analysed in conventional myositis blot assays for diagnostic purposes in clinical ILD care requires further study.

Quantification of pulmonary disease activity in sarcoidosis measured with 18F-FDG PET/CT: SUVmax versus total lung glycolysis.

BACKGROUND: 18F-FDG PET/CT has proven to be a reliable tool for therapy monitoring in sarcoidosis. Previous PET studies investigated the SUVmax as a marker for disease activity. Total lung glycolysis (TLuG) is a new tool, quantifying the glycolysis of the entire lung. Since SUVmax represents the maximum activity in only one pixel, we hypothesize that TLuG is a more accurate marker for active pulmonary disease and predictor of response than SUVmax. METHODS: In this retrospective cohort study, 27 patients started on infliximab for refractory pulmonary sarcoidosis. Patients received infliximab intravenously monthly at a dose of 5 mg/kg. We performed a lung function test and an 18F-FDG PET/CT before initiation of infliximab and after 6 months of treatment. SUVmax and TLuG were determined in the pre- and post-scan. Change in lung function was correlated with the change in SUVmax and TLuG and was correlated to the initial SUVmax and TLuG to evaluate the predictive value of the initial metabolic activity. RESULTS: ΔSUVmax significantly correlated with ΔFVC (r = - 0.497, p = 0.008) and with ΔFEV1 (r = - 0.467, p = 0.014). Furthermore, ΔTLuG significantly correlated with ΔFVC (r = - 0.430, p = 0.025), ΔFEV1 (r = - 0.532, p = 0.004) and ΔDLCOc (r = - 0.423, p = 0.039). Change in SUVmax and TLuG significantly correlated (r = 0.735, p < 0.001). Initial SUVmax significantly correlated with the change in FVC and DLCOc. In addition, initial TLuG significantly correlated with the change in FEV1 and DLCOc. A SUVmax > 7.5 at initiation of infliximab was predictive for 5% response in FVC, whereas SUVmax > 9.2 was predictive for 5% response in DLCOc. In addition, high TLuG > 4100 at initiation of infliximab was predictive for 5% response in FVC and FEV1 and TLuG > 4500 was predictive for response in DLCOc. CONCLUSION: SUVmax and TLuG are equal in determining the response to infliximab in pulmonary sarcoidosis patients. Furthermore, SUVmax and TLuG at initiation of infliximab can predict change in lung function after treatment. Since TLuG is a more time-consuming tool, we recommend to use SUVmax of the lung parenchyma for response monitoring in pulmonary sarcoidosis.

Efficacy and safety of infliximab biosimilar Inflectra® in severe sarcoidosis.

BACKGROUND: Infliximab, a monoclonal antibody against tumor necrosis factor alpha (TNF-α) is effective third-line therapy in severe sarcoidosis. The originator product of Infliximab, Remicade®, is expensive, limiting universal access. Recently, a less expensive biosimilar of infliximab, Inflectra®, has become available, but the efficacy and tolerability has not been studied in sarcoidosis. METHODS: In this retrospective cohort study, 29 patients treated with the infliximab biosimilar Inflectra®, were analysed. Patients received Inflectra® intravenously monthly at a dose of 5 mg/kg. We measured trough levels before every infusion. Before and after 6 months of induction therapy pulmonary function and disease activity were evaluated using Standardised Uptake Value (SUV) of the 18F-fluorodeoxyglucose by positron emission tomography (18F-FDG PET), soluble interleukin-2 receptor (sIL-2R), angiotensin converting enzyme (ACE) and health-related quality of life (HRQOL). RESULTS: In patients with pulmonary sarcoidosis as main treatment indication (n = 15) the predicted FVC improved with 8.1%, p < 0.05. Furthermore, in the whole group HRQoL improved significantly (p < 0.001), whereas SUVmax and sIL-2R significantly reduced (p < 0.001 and p = 0.001 respectively). Hospitalisation due to infections occurred in four patients. None of the patients discontinued Inflectra® due to side-effects. Furthermore, all patients had detectable trough levels indicating development of neutralizing antibodies. CONCLUSION: Infliximab biosimilar Inflectra® seems effective in the treatment of refractory sarcoidosis with a comparable safety profile to the reference product Remicade®. Inflectra® can be considered as an alternative and less expensive option for patients with refractory sarcoidosis.

Efficacy of adalimumab in sarcoidosis patients who developed intolerance to infliximab.

BACKGROUND: Tumor necrosis factor-alpha (TNF-α) inhibitors are regarded as the third-line therapy in sarcoidosis, the first choice generally being infliximab. To date, data regarding response to adalimumab in sarcoidosis patients intolerant to infliximab are lacking. The objective of this retrospective observational study was to establish if adalimumab could achieve stabilization or improvement of the disease in refractory sarcoidosis patients who developed intolerance to infliximab. MATERIAL AND METHODS: Sarcoidosis patients referred to St Antonius Interstitial Lung Diseases Center of Excellence, Nieuwegein, The Netherlands, between January 2008 and April 2015 who switched from infliximab to adalimumab were included. Changes in organ function, inflammatory biomarker levels, and adverse events were retrieved from medical records. RESULTS: Out of 142 infliximab treated patients, 18 (13%) had to discontinue treatment due to antibody formation or severe adverse events and switched to adalimumab therapy. Organ function improved in 7 patients (39%), was stable in 6 patients (33%), and worsened in 5 patients (28%) after 12 months of treatment or after 6 months if evaluation after 12 months was not available (n = 4). In none of the patients biomarker levels of soluble interleukin-2 receptor (sIL-2R) deteriorated. Median decrease in sIL-2R was 3614 pg/mL. Most reported adverse event was infection (n = 10). CONCLUSIONS: Adalimumab is an effective alternative for patients intolerant to infliximab. The switch to adalimumab achieved clinical improvement in 39% and stabilization in 33% of patients intolerant to infliximab. Further research is needed to develop guidelines on how to use adalimumab for sarcoidosis in terms of dosing regimen.

ACE and sIL-2R correlate with lung function improvement in sarcoidosis during methotrexate therapy.

INTRODUCTION: In sarcoidosis, the search for disease activity markers that correlate with treatment response is ongoing. The aim of this study was to investigate the pattern of two proposed markers, serum angiotensin-converting enzyme (ACE) and soluble IL-2 receptor (sIL-2R) during methotrexate (MTX) therapy in sarcoidosis patients. MATERIALS AND METHODS: We analysed 114 sarcoidosis patients who used MTX for six months, consisting of a subgroup of 76 patients with a pulmonary indication for treatment and a subgroup of 38 patients with an extra-pulmonary indication. ACE and sIL-2R serum levels were measured at baseline and after six months of treatment. Correlation coefficients (R) and odds ratios (ORs) were calculated to study the correlation and predictive effect of serum ACE and sIL-2R levels for pulmonary improvement. RESULTS: High baseline levels of ACE correlated significantly with lung function improvement after treatment (R = 0.45, p < 0.0001; stronger in the pulmonary subgroup R 0.57, p < 0.0001). ACE baseline levels >90 U/l predicted a 10% improvement in overall lung function (OR 3.55; CI 1.34-9.38), with the highest prediction level for 10% improvement in DLCO (OR 4.63; CI 1.23-17.4). After six months of MTX, mean ACE decreased with 17.2 U/l (p < 0.0001) and sIL-2R with 1850 pg/ml (p < 0.0001). Decreases in both ACE and sIL-2R correlated with an increase in lung function. The strongest correlation was found with change in DLCO in the pulmonary subgroup (ACE R = 0.63, P < 0.0001; sIL-2R R = 0.56, P < 0.0001). CONCLUSION: Baseline and serial serum ACE and sIL-2R levels correlate well with lung function improvement during MTX treatment. Serial measurements of these biomarkers are helpful in monitoring treatment effects in sarcoidosis patients.