Summary: Background:Until now, a proper biomarker(s) to evaluate sarcoidosis activity has not been recognized. The aims of this study were to evaluate the sensitivity and specificity of the two biomarkers of sarcoidosis activity already in use (serum angiotensin converting enzyme – ACE and serum chitotriosidase) in a population of 430 sarcoidosis patients. The activities of these markers were also analyzed in a group of 264 healthy controls.Methods:Four hundred and thirty biopsy positive sarcoidosis patients were divided into groups with active and inactive disease, and groups with acute or chronic disease. In a subgroup of 55 sarcoidosis patients, activity was also assessed by F-18 fluorodeoxyglucose positron emission tomography (¹⁸F-FDG-PET) scanning. Both serum chitotriosidase and ACE levels showed non-normal distribution, so nonparametric tests were used in statistical analysis.Results:Serum chitotriosidase activities were almost 6 times higher in patients with active sarcoidosis than in healthy controls and inactive disease. A serum chitotriosidase value of 100 nmol/mL/h had the sensitivity of 82.5% and specificity of 70.0%. A serum ACE activity cutoff value of 32.0 U/L had the sensitivity of 66.0% and the specificity of 54%. A statistically significant correlation was obtained between the focal granulomatous activity detected on¹⁸F-FDG PET/CT and serum chitotriosidase levels, but no such correlation was found with ACE. The levels of serum chitotriosidase activity significantly correlated with the disease duration (P<0.0001). Also, serum chitotriosidase significantly correlated with clinical outcome status (COS) categories (ρ=0.272,P=0.001).Conclusions:Serum chitotriosidase proved to be a reliable biomarker of sarcoidosis activity and disease chronicity.

Calcium metabolism impairments have long been recognized as a complication of sarcoidosis. For more than six decades physicians and investigators have been trying to elucidate this severe problem; nevertheless it seems puzzlingly new for both readers and researchers. This review highlights the problems of calcium metabolism in sarcoidosis in relation to vitamin D synthesis, which is definitely altered by granulomatous inflammation. Increasing evidence suggests that vitamin D is an immunomodulating hormone that inhibits both antigen presentation by cells of the innate immune system, and the cytokine release and proliferation of Th1 cells. As calcium homeostasis is primary controlled by levels of vitamin D, parathyroid hormone (PTH) and calcitonin, this literature review emphasizes the role of general immunomodulating properties of vitamin D and the correlation with calcium metabolism impairments, with the special accent on already known interactions with sarcoidosis. Granuloma formation has been related to a failure of the innate immune system. One of the possible explanations is a vitamin D deficiency. The evidence-based findings on calcium metabolism impairments and the interactions with vitamin D might help both clinicians and researchers in developing new strategies.

Introduction: Between February and November 2016, 17 tuberculosis (TB) cases were identified among high school students in Novi Pazar, Serbia. The objectives of our study were to describe the outbreak, to identify potential risk factors and to evaluate the applied control measures. Methodology: The outbreak was described by time, person and place. A retrospective cohort study was conducted. Attack rates, unadjusted relative risks (RR) and 95% confidence intervals (CI) were calculated. Multiple log-binomial regression analysis was performed to calculate adjusted RR. Results: Sixteen of the total 17 cases occurred among grade 3 students, AR 5.5%. Previous TB family history, (RR = 5.29; 95% CI = 1.63-17.12), spending time with a known TB case at school (RR = 5.38; 95% CI = 1.48-19.55) and exposure to secondhand smoke (RR = 3.37; 95% CI = 1.11-10.29) were all significantly and independently associated with the occurrence of TB. Conclusions: Delayed diagnosis and reporting resulted in delayed initiation of the contact investigation and non-identification of latent TB cases probably favored the occurrence of this outbreak in a low incidence country. Public health authorities should consider revising the existing guidelines, promoting inter-sectorial collaboration and increasing awareness of public health professionals.

Fatigue is a prominent symptom in a large number of medical conditions, malignant and infectious diseases. Fatigue is also a prominent symptom of sarcoidosis. The occurrence of fatigue in sarcoidosis is well known but exact incidence has not been established and varies from 30-70% of patients depending on age, sex and organ involvement by the granulomatous process. The exact definition of fatigue varies broadly. It can be both physical and mental. The patients describe their sensation of fatigue qualitatively different from that fatigue they experienced before they became sick. Fatigue has a major impact on the quality of life in sarcoidosis. Establishing the extent of fatigue in sarcoidosis provides relevant insight regarding the patient’s quality of life. Unfortunately there is no objective parameter for assessing fatigue in sarcoidosis. Generally, fatigue is detected by means of questionnaires. Regarding the therapy, there is no effective treatment for fatigue in sarcoidosis.

Objective: The aim of this study was to use a Serbian-language version of the disease-specific, self-report Sarcoidosis Health Questionnaire (SHQ), which was designed and originally validated in the United States, to assess health status in sarcoidosis patients in Serbia, as well as validating the instrument for use in the country. Methods: This was a cross-sectional study of 346 patients with biopsy-confirmed sarcoidosis. To evaluate the health status of the patients, we used the SHQ, which was translated into Serbian for the purposes of this study. We compared SHQ scores by patient gender and age, as well as by disease duration and treatment. Lower SHQ scores indicate poorer health status. Results: The SHQ scores demonstrated differences in health status among subgroups of the sarcoidosis patients evaluated. Health status was found to be significantly poorer among female patients and older patients, as well as among those with chronic sarcoidosis or extrapulmonary manifestations of the disease. Monotherapy with methotrexate was found to be associated with better health status than was monotherapy with prednisone or combination therapy with prednisone and methotrexate. Conclusions: The SHQ is a reliable, disease-specific, self-report instrument. Although originally designed for use in the United States, the SHQ could be a useful tool for the assessment of health status in various non-English-speaking populations of sarcoidosis patients.