Exploring the association between melatonin and nicotine dependence (Review).

Due to the addictive qualities of tobacco products and the compulsive craving and dependence associated with their use, nicotine dependence continues to be a serious public health concern on a global scale. Despite awareness of the associated health risks, nicotine addiction contributes to numerous acute and chronic medical conditions, including cardiovascular disease, respiratory disorders and cancer. The nocturnal secretion of pineal melatonin, known as the 'hormone of darkness', influences circadian rhythms and is implicated in addiction­related behaviors. Melatonin receptors are found throughout the brain, influencing dopaminergic neurotransmission and potentially attenuating nicotine­seeking behavior. Additionally, the antioxidant properties of melatonin may mitigate oxidative stress from chronic nicotine exposure, reducing cellular damage and lowering the risk of nicotine­related health issues. In addition to its effects on circadian rhythmicity, melatonin acting via specific neural receptors influences sleep and mood, and provides neuroprotection. Disruptions in melatonin signaling may contribute to sleep disturbances and mood disorders, highlighting the potential therapeutic role of melatonin in addiction and psychiatric conditions. Melatonin may influence neurotransmitter systems involved in addiction, such as the dopaminergic, glutamatergic, serotonergic and endogenous opioid systems. Preclinical studies suggest the potential of melatonin in modulating reward processing, attenuating drug­induced hyperactivity and reducing opioid withdrawal symptoms. Chronotherapeutic approaches targeting circadian rhythms and melatonin signaling show promise in smoking cessation interventions. Melatonin supplementation during periods of heightened nicotine cravings may alleviate withdrawal symptoms and reduce the reinforcing effects of nicotine. Further research is required however, to examine the molecular mechanisms underlying the melatonin­nicotine association and the optimization of therapeutic interventions. Challenges include variability in individual responses to melatonin, optimal dosing regimens and identifying biomarkers of treatment response. Understanding these complexities could lead to personalized treatment strategies and improve smoking cessation outcomes.

Association between polymorphisms of DNA repair genes and intracranial aneurysms: A systematic review and meta­analysis.

Intracranial aneurysms (IAs) are present in ~2% of the general population, and genetic factors cannot be excluded for the risk of their development. The gene factors that result in the changes in the vascular extracellular matrix (ECM) may also be a key reason for IAs being hereditary. The VCAN gene [also known as chondroitin sulfate proteoglycan 2 (CSPG2)] plays various roles in maintaining ECM functions. The present systematic review and meta-analysis aimed to investigate all eligible articles involving IAs on the association with germ line SNPs of DNA repair genes (up to January, 2024). The total number of patients was 2,308 [987 cases (poor outcomes) and 1,321 controls (good outcomes)]. The results revealed that rs2287926 G/G genotype and G allele and rs251124 T/T genotype and minor allele T increased the risk of developing IAs. However, further studies are required to examine these gene polymorphisms as screening markers for IAs.

Comparison of surgical techniques for the treatment of chronic subdural hematomas: A single­center case series.

Chronic subdural hematoma (CSDH) is one of the most challenging realities in the neurosurgical world. The aim of the present study was to compare different surgical techniques, such as burr hole evacuation with subperiosteal drain or subdural drain and mini-craniotomy, and to review the diverse outcomes on the post-operative clinical state of patients. The present study was a retrospective cohort study with 122 patients with CSDH treated at a single center. The patients were separated into three groups according to the surgical technique used as follows: group 1, two burr holes with the placement of a subperiosteal drain; group 2, single burr hole per hematoma with the placement of an intradural drain; and group 3, mini-craniotomy. The duration of hospitalization, hematoma recurrence, complications, Glasgow coma scale at discharge and mortality were reported as outcome measures. A total of 3 patients succumbed following hematoma evacuation; of these 2 patients were from group 2 and 1 patient was from group 3. The patients from groups 1 and 3 exhibited a significantly lower odds ratio (OR) of hematoma recurrence than patients in group 2 (OR, 0.76; P<0.01; and OR, 0.8; P<0.01, respectively). The patients in group 1 exhibited a significantly lower probability of having a depressed level of consciousness on discharge (OR, 0.249; P=0.031). Group 2 was associated with a statistically significant prolongation of hospitalization. On the whole, the present study demonstrates that multiple burr hole hematoma evacuation with subperiosteal drain placement and mild suction is a very promising technique with very beneficial post-operative outcomes, such as zero mortality, a low CSDH recurrence risk, a reduced period of hospitalization and an improved post-operative quality of life.

Malignant character of an ossified posterior longitudinal ligament in a hyperflexion injury: A case report.

The present study reports the case of a 50-year-old obese male with ankylosing spondylitis, Scheuermann's kyphosis. The patient was asymptomatic concerning the ectopic ossification of the posterior longitudinal ligament (OPLL) at the cervical spine; he developed quadriparesis and respiratory insufficiency following minor head trauma. Even though trauma to the cervical spine in patients with OPLL is common, to the best of our knowledge, this is the first reported case of an extensive osteophyte with a lethal outcome after syncope. In rare occasions, it may be present with syncope and potentially lethal outcomes, particularly when precipitated by trauma. Therefore, the management of OPLL with significant canal stenosis should not be unnecessarily delayed.

Prevalence of ACA variations: A systematic review and meta­analysis.

The anterior cerebral artery (ACA) and its divisions enclose symptomatically critical and supplementary differentiations. Anatomical variations of the distal ACA that are irregularly detected can be separated into three major groups, namely, azygos, bihemispheric and median ACA variations. The present study performed a systematic review and meta-analysis. The PICOS criteria and electronic databases, namely the Cochrane Library, PubMed (until December, 2023), Embase (until December, 2023) and MEDLINE (until December, 2023) were used to identify 48 articles to fulfill the eligible criteria. As a limited number of studies exist on the prevalence of ACA anatomical variations, the present meta-analysis aimed to determine the precise incidence of these variants. In addition, with the comparative description between cadaveric (autopsy) and imaging cases, more accurate results were extract from the prevalence presentation of the distal ACA variants. On the whole, no statistically significant differences were found between autopsy and imaging studies.

Acute intracranial hemorrhage during the installation of the LICOX microdialysis system: A case report.

Neuro-monitoring is widely employed for the evaluation of intubated patients in the intensive care unit with stroke, severe head trauma, subarachnoid hemorrhage and/or hepatic encephalopathy. The present study reports the case of a patient with acute intracranial hemorrhage following the insertion of neuromonitoring catheters, which required surgical management. The patient was a 14-year-old male who sustained a severe traumatic brain injury and underwent a right-sided hemicraniectomy. During the installation of the neuromonitoring catheters, an acute hemorrhage was noted with a rapidly elevating intracranial pressure. A craniotomy was performed to identify and coagulate the injured cortical vessel. As demonstrated herein, the thorough evaluation of the clotting profile of the patient, a meticulous surgical technique and obtaining a post-insertion computed tomography scan may minimize the risk of any neuromonitoring-associated hemorrhagic complications.

Awake craniotomy in patients with arteriovenous malformation: A systematic review and meta­analysis.

The present systematic review aimed to identify all the available literature on awake craniotomy (AC) in patients with arteriovenous malformation (AVM) in order to evaluate its safety, risks, benefits and effectiveness. All available literature on AC in patients with AVM was collected and evaluated in an aim to provide a better understanding of its safety, associated risks and benefits. A systematic search for studies employing AC in patients with AVM was conducted using the PubMed, Scopus and ScienceDirect databases without restrictions on the year of publication, language, or study design, from inception up to May 30, 2021. A total of 11 studies published between 2004 and 2021 with 106 patients who underwent ACs were considered eligible. The rate of complete resection was 93% [95% confidence interval (CI), 82 to 100%; I2 0%]. The intraoperative complication rate was 21% (95% CI, 1 to 41%; I2 55%) and the post-operative complication rate was 33% (95% CI, 19 to 48%; I2 40%). During follow-up, the complication rate was 6% (95% CI, 1 to 10%; I2 30%). The post-operative complication rate was higher in the Spetzler-Martin grade (SMG) III-V group (31%; 95% CI, 21 to 42%; I2 46%) than in the SMG I-II group (12%; 95% CI, 2 to 22%; I2 0%). Similarly, the follow-up complication rate was higher in the SMG III-V group (9%; 95% CI, 2 to 16%; I2 34%) than in the SMG I-II group (0%; 95% CI, 0 to 4%; I2 0%). On the whole, the present study provides preliminary evidence to indicate that AC is a possible and useful option for the resection of AVM in selected patients. Well-designed future studies with long-term follow-up are required however, to investigate various aspects of safety and provide solid data for AC in patients with AVM.

Exploring the pathogenetic mechanisms of Mycoplasmapneumoniae (Review).

Mycoplasmas, the smallest self-replicating prokaryotes without a cell wall, are the most prevalent and extensively studied species in humans. They significantly contribute to chronic respiratory tract illnesses and pneumonia, with children and adolescents being particularly vulnerable. Mycoplasma pneumoniae (M. pneumoniae) infections typically tend to be self-limiting and mild but can progress to severe or even life-threatening conditions in certain individuals. Extrapulmonary effects often occur without pneumonia, and both intrapulmonary and extrapulmonary complications operate through separate pathological mechanisms. The indirect immune-mediated damage of the immune system, vascular blockages brought on by vasculitis or thrombosis and direct harm from invasion or locally induced inflammatory cytokines are potential causes of extrapulmonary manifestations due to M. pneumoniae. Proteins associated with adhesion serve as the primary factor crucial for the pathogenicity of M. pneumoniae, relying on a specialized polarized terminal attachment organelle. The type and density of these host receptors significantly impact the adhesion and movement of M. pneumoniae, subsequently influencing the pathogenic mechanism and infection outcomes. Adjacent proteins are crucial for the proper assembly of the attachment organelle, with variations in the genetic domains of P1, P40 and P90 surfaces contributing to the variability of clinical symptoms and offering new avenues for developing vaccines against M. pneumoniae infections. M. pneumoniae causes oxidative stress within respiratory tract epithelial cells by adhering to host cells and releasing hydrogen peroxide and superoxide radicals. This oxidative stress enhances the vulnerability of host cells to harm induced by oxygen molecules. The lack of superoxide dismutase and catalase of bacteria allows it to hinder the catalase activity of the host cell, leading to the reduced breakdown of peroxides. Lung macrophages play a significant role in managing M. pneumoniae infection, identifying it via Toll-like receptor 2 and initiating the myeloid differentiation primary response gene 88-nuclear factor κΒ signaling cascade. However, the precise mechanisms enabling M. pneumoniae to evade intracellular host defenses remain unknown, necessitating further exploration of the pathways involved in intracellular survival. The present comprehensive review delves into the pathogenesis of M. pneumoniae infection within the pulmonary system and into extrapulmonary areas, outlining its impact.

Comparison of surgical outcomes between primary and secondary brain abscess.

Brain abscess (BA) constitutes 1-8% of intra-cerebral tumors, and thus the present study aimed to compare the surgical outcomes of patients with primary and secondary BA. The present retrospective study examined 32 of cases BA who underwent surgery in a local institution between February, 2013 and December, 2023. All patients received intravenous antibiotic therapy according to the antibiogram for antimicrobial susceptibility. In total, 32 patients were separated into two groups as follows: Group A (16 patients, 50%) with primary abscess and group B (16 patients, 50%) with secondary abscess. Of the 32 patients included in the study, 23 (71.8%) were males, and the median age was 55.3 years. On the whole, the present study demonstrates that a multidisciplinary approach involving a combination of often multiple surgical procedures and prolonged antibiotic medication may improve the functional outcome if the underlying pathology allows for a functional outcome.

Clinical, Histopathological, and Immunohistochemical Characteristics of Predictive Biomarkers of Breast Cancer: A Retrospective Study.

Background/Aim: Breast cancer is a complex disease with variability in clinical manifestation, response to current therapy, and biochemical and histological features among various subgroups. Histologic grading and immuno-histochemical evaluation of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), and Ki-67 proliferation index play a crucial role in increasing the differential diagnostic value among various types of breast carcinoma. The aim of this study was to determine the histopathological and immuno-histochemical characteristics of breast tumors from a University Laboratory of Pathology in Greece. Patients and Methods: The study included female patients over 18 years of age, whose histopathological and immunohistochemical reports were stored in the archives of the First Department of Pathology of National and Kapodistrian University of Athens. The study involved 197 female patients with a median age of 70 years and median tumor size of 2.6 cm. Results: Most tumors were located at the left breast and ductal carcinoma was the most common histologic type (35.5%). Most tumors had histologic grade 2 (106, 53.8%), and were classified as TNM stage IIA (65, 33%). Most grade 1 and 2 tumors exhibited high expression of PR, whereas most grade 3 tumors had no PR expression. Moreover, patients with triple-negative cancer presented with grades 2 and 3 at a lower percentage compared to patients without a triple-negative phenotype (p=0.001). Conclusion: The study provided valuable insights into the histopathological and immuno-histochemical characteristics involved in the development and progression of breast cancer.

Management of intracranial cavernous malformations using conservative vs. surgical and/or radiosurgical treatment: A systematic review and meta­analysis.

Intracranial cavernous malformations (CMs) are vascular lesions with a high bleeding rate. At present, the debate regarding their treatment is still ongoing. The present systematic review and meta-analysis aimed to evaluate the safety of surgery or radiosurgery (SRS) for the management of CMs and to determine their potential outcomes compared with conservative treatment. The present systematic review and meta-analysis investigated the relative articles involving the management of intracranial CMs, namely their natural history (conservative treatment) vs. surgical/SRS treatment through electronic databases until June, 2023. The collected variables included the first author's name, the study period covered, the year of publication, the total number of patients examined and their age, and the number of males. In total, six articles met the eligibility criteria. The total number of patients was 399 (157 in the surgery/SRS group and 242 in the conservative treatment group). The results revealed that surgical or SRS management is a safe procedure for CMs compared with conservative treatment. Notably, the use of hemosiderin in the pre-MRI, the free of seizures parameter and the neurological deficit parameters were associated with improved outcomes in the surgical or SRS group of patients.

Precision medicine for respiratory diseases: A current viewpoint.

In the realm of respiratory illnesses, despite the immense costs and efforts invested in diagnosis and treatment, numerous patients with chronic respiratory conditions or malignancies do not respond well to existing therapies. Delayed diagnoses and inadequate treatments contribute to these challenges, along with adverse reactions or treatment limitations due to side-effects. However, recent advancements in understanding respiratory diseases have paved the way for personalized medical treatments, considering individual genetic, molecular and environmental factors. Precision medicine, which accommodates individual differences in disease susceptibility and response to treatments, aims to improve patient care by aligning medical research with tailored therapies. Innovative technologies, such as genomic sequencing and biomarker identification contribute to this approach, allowing for customized treatments and the identification of effective therapies. Additionally, the application of precision medicine in lung cancer treatment exemplifies the forefront of individualized care within respiratory medicine. Several studies have explored the role of precision medicine in managing respiratory infectious diseases, asthma and idiopathic pulmonary fibrosis, aiming to categorize diseases more accurately and design targeted therapies. The ultimate goal is to enhance treatment effectiveness, minimize adverse events, and shift towards a patient-centered approach to managing respiratory conditions. Despite limitations, precision medicine holds promise for improving patient outcomes and emphasizing personalized care in respiratory medicine.

Bone graft absorption complication following cranioplasty: A retrospective institutional study.

The aim of the present retrospective study was to confer the factors that are related to bone graft absorption and affect the outcomes of patients following cranioplasty (CPL). The present retrospective study includes cases of patients that underwent CPL between February, 2013 and December, 2022. All participants had a follow-up period of 1 to 10 years from the day of discharge from the hospital. In total, 116 (62.3%) of the 186 patients that underwent decompressive craniectomy (DC) were enrolled in the present study for CPL. A total of 109 (93.9%) patients were included in group A, and 7 (6.0%) patients were included in group B. On the whole, the results of the present study suggest that a CPL after 2.5-7.7 months of DC increases the possibility of bone absorption.

The parallel lives of pandemics: COVID­19 and obesity.

The present article discusses the interconnectedness of coronavirus disease 2019 (COVID-19) and obesity as global health crises. The similarities between the two conditions are highlighted; these include shared risk factors and comorbidities, and the impact of obesity on the immune system. The present article also mentions the challenges faced in combating both pandemics, including misinformation and prejudice against obesity. It discusses the development of therapeutic medications and vaccines for COVID-19 and the potential of injectable incretin analogues for weight loss. Socioeconomic issues are also addressed, with obesity being more prevalent in lower socioeconomic groups and the cost of obesity treatments being a barrier for those in need. The present article emphasizes the need for comprehensive and sustainable solutions, including public health interventions, education, policy changes and equitable distribution of resources, to address both COVID-19 and obesity.

Role of microRNAs in cognitive decline related to COVID­19 (Review).

The likelihood and severity of cognitive decline related to coronavirus disease 2019 (COVID-19) have been shown to be reflected by the severity of the infection and concomitant alterations in specific biomarkers. The present review discusses the role of microRNAs (miRNAs/miRs) as biomarkers in COVID-19 and the potential molecular mechanisms of cognitive dysfunction related to COVID-19. A systematic search of published articles was carried out from January 31, 2000 to December 31, 2022 using the PubMed, ProQuest, Science Direct and Google Scholar databases, combining the following terms: 'COVID-19' OR 'SARS-CoV-2' OR 'post-COVID-19 effects' OR 'cognitive decline' OR 'neurodegeneration' OR 'microRNAs'. The quality of the evidence was evaluated as high, moderate, low, or very low based on the GRADE rating. A total of 36 studies were identified which demonstrated reduced blood levels of miR-146a, miR-155, Let-7b, miR 31 and miR-21 in patients with COVID-19 in comparison with a healthy group. The overexpression of the Let-7b may result in the downregulation of BCL-2 during COVID-9 by adjusting the immune responses between chronic inflammatory disease, type 2 diabetes, COVID-19 and cognitive impairment. The reduced expression of miR-31 is associated with cognitive dysfunction and increased microcoagulability in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). miR-155 mediates synaptic dysfunction and the dysregulation of neurotransmitters due to acute inflammation, leading to brain atrophy and a subcortical cognitive profile. The downregulation of miR-21 in patients with COVID-19 aggravates systemic inflammation, mediating an uncontrollable immune response and the failure of T-cell function, provoking cognitive impairment in patients with SARS-CoV-2. On the whole, the present review indicates that dysregulated levels of miR-146a, miR-155, Let-7b, miR-31, and miR-21 in the blood of individuals with COVID-19 are associated with cognitive decline, the chronic activation of immune mechanisms, the cytokine storm, and the vicious cycle of damage and systemic inflammation.

A mid­pandemic night's dream: Melatonin, from harbinger of anti­inflammation to mitochondrial savior in acute and long COVID­19 (Review).

Coronavirus disease 2019 (COVID­19), a systemic illness caused by severe acute respiratory distress syndrome 2 (SARS­CoV­2), has triggered a worldwide pandemic with symptoms ranging from asymptomatic to chronic, affecting practically every organ. Melatonin, an ancient antioxidant found in all living organisms, has been suggested as a safe and effective therapeutic option for the treatment of SARS­CoV­2 infection due to its good safety characteristics and broad­spectrum antiviral medication properties. Melatonin is essential in various metabolic pathways and governs physiological processes, such as the sleep­wake cycle and circadian rhythms. It exhibits oncostatic, anti­inflammatory, antioxidant and anti­aging properties, exhibiting promise for use in the treatment of numerous disorders, including COVID­19. The preventive and therapeutic effects of melatonin have been widely explored in a number of conditions and have been well­established in experimental ischemia/reperfusion investigations, particularly in coronary heart disease and stroke. Clinical research evaluating the use of melatonin in COVID­19 has shown various improved outcomes, including reduced hospitalization durations; however, the trials are small. Melatonin can alleviate mitochondrial dysfunction in COVID­19, improve immune cell function and provide antioxidant properties. However, its therapeutic potential remains underexplored due to funding limitations and thus further investigations are required.

Surgical outcomes of patients with unruptured anterior vs. inferior circulation aneurysms: A meta­analysis.

The treatment option for unruptured intracranial aneurysms (UIAs) depends on their natural history-related risk of rupture vs. the risk of surgical management. The present meta-analysis sought to assess the association between the surgical outcomes of anterior and posterior circulation UIAs. The present study investigated the comparative articles involving the surgical treatment of anterior vs. posterior circulation UIAs through electronic databases, including the Cochrane Library, PubMed (1980 to March, 2023), Medline (1980 to March, 2023) and EMBASE (1980 to March, 2023). Quoting all exclusion and inclusion criteria, nine articles finally remained for statistical analysis. The entire number of patients included in these nine articles was 3,253 (2,662 in the anterior and 591 in the posterior circulation UIAs group). The present meta-analysis proposes that the surgical treatment of anterior circulation UIAs is associated with better outcomes compared with the surgical management of posterior circulation UIAs.

Role of decompressive craniectomy in the management of acute ischemic stroke (Review).

The application of decompressive craniectomy (DC) is thoroughly documented in the management of brain edema, particularly following traumatic brain injury. However, an increasing amount of concern is developing among the universal medical community as regards the application of DC in the treatment of other causes of brain edema, such as subarachnoid hemorrhage, cerebral hemorrhage, sinus thrombosis and encephalitis. Managing stroke continues to remain challenging, and demands the aggressive and intensive consulting of a number of medical specialties. Middle cerebral artery (MCA) infarcts, which consist of 1-10% of all supratentorial infarcts, are often associated with mass effects, and high mortality and morbidity rates. Over the past three decades, a number of neurosurgical medical centers have reported their experience with the application of DC in the treatment of malignant MCA infarction with varying results. In addition, over the past decade, major efforts have been dedicated to multicenter randomized clinical trials. The present study reviews the pertinent literature to outline the use of DC in the management of malignant MCA infarction. The PubMed database was systematically searched for the following terms: 'Malignant cerebral infarction', 'surgery for stroke', 'DC for cerebral infarction', and all their combinations. Case reports were excluded from the review. The articles were categorized into a number of groups; the majority of these were human clinical studies, with a few animal experimental clinical studies. The surgical technique involved was DC, or hemicraniectomy. Other aspects that were included in the selection of articles were methodological characteristics and the number of patients. The multicenter randomized trials were promising. The mortality rate has unanimously decreased. As for the functional outcome, different scales were employed; the Glasgow Outcome Scale Extended was not sufficient; the Modified Rankin Scale and Bathel index, as well as other scales, were applied. Other aspects considered were demographics, statistics and the very interesting radiological ones. There is no doubt that DC decreases mortality rates, as shown in all clinical trials. Functional outcome appears to be the goal standard in modern-era neurosurgery, and quality of life should be further discussed among the medical community and with patient consent.

Lung function at three months after hospitalization due to COVID­19 pneumonia: Comparison of alpha, delta and omicron variant predominance periods.

The coronavirus disease (COVID-19) pandemic has already affected millions of individuals, with increasing numbers of survivors. These data suggest that the pulmonary sequelae of the infection may have an effect on a wide range of individuals. The aim of the present study was to evaluate pulmonary function in patients hospitalized due to COVID-19 three months after hospital discharge. A total of 116 patients, 34 females and 82 males, with a mean age of 57.77±11.45 years, who were hospitalized due to COVID-19, underwent pulmonary function testing three months after their hospital discharge. Of these, 83 (71.6%) patients were hospitalized in the period of alpha variant predominance, 16 (13.8%) in the period of delta variant predominance and 17 (14.6%) in the omicron variant predominance period. The mean value of diffusion capacity for carbon monoxide (DLCO)% predicted (pred) was statistically higher in patients affected by the omicron variant (P=0.028). Abnormal values (<80% pred) of DLCO and total lung capacity (TLC) were observed in 28.4 and 20.7% of the patients, respectively. Active smoking was an independent predictor of abnormal values of forced expiratory volume in 1 sec % pred and TLC% pred [P=0.038; odds ratio (OR): 8.574, confidence interval (CI) 1.124-65.424 and P=0.004, OR: 14.733, CI 2.323-93.429, respectively], age was an independent predictor of abnormal values of forced vital capacity % pred and DLCO% pred (P=0.027, OR: 1.124, CI 1.014-1.246 and P=0.011, OR:1.054, CI 1.012-1.098, respectively); and female sex was an independent predictor of abnormal values of DLCO% pred (P=0.009, OR: 1.124, CI 1.014-1.246). Α significant percentage of hospitalized patients due to COVID-19 pneumonia will develop abnormal pulmonary function, regardless of the SARS-CoV-2 variant.

Temporal trends in laboratory parameters in survivors and non­survivors of critical COVID­19 illness and the effect of dexamethasone treatment.

Although coronavirus disease 2019 (COVID-19)-induced changes in laboratory parameters in patients upon admission have been well-documented, information on their temporal changes is limited. The present study describes the laboratory trends and the effect of dexamethasone treatment on these parameters, in patients with COVID-19 in the intensive care unit (ICU). Routine laboratory parameters, namely white blood cell (WBC), neutrophil, lymphocyte and platelet (PLT) counts, fibrinogen, C-reactive protein (CRP), lactate dehydrogenase (LDH) and albumin concentrations, were recorded upon admission to the ICU and, thereafter, on days 3, 5, 10, 15 and 21; these values were compared between survivors and non-survivors, as well as between those who were treated with dexamethasone and those who were not. Among the 733 patients in the ICU, (mean age, 65±13 years; 68% males; ICU mortality rate 45%; 76% of patients treated with dexamethasone), the WBC and neutrophil counts were persistently high in all patients, without significant differences over the first 15 days. Initially, low lymphocyte counts exhibited increasing trends, but remained higher in survivors compared to non-survivors (P=0.01). The neutrophil-to-lymphocyte ratio (NLR) was persistently elevated in all patients, although it was significantly higher in non-survivors compared to survivors (P<0.001). The PLT count was initially increased in all patients, although it was significantly decreased in non-survivors over time. The fibrinogen and LDH values remained similarly elevated in all patients. However, the increased levels of CRP, which did not differ between patients upon admission, further increased in non-survivors compared to survivors after day 10 (P=0.001). Declining trends in albumin levels over time, overall, with a significant decrease in non-survivors compared to survivors, were observed. Dexamethasone treatment significantly affected the temporal progression of fibrinogen and CRP in survivors and that of NLR in non-survivors. On the whole, the present study demonstrates that patients in the ICU with COVID-19 present persistently abnormal laboratory findings and significant differences in laboratory trends of NLR, CRP, PLT and albumin, but not in WBC and neutrophil count, and fibrinogen and LDH levels, between survivors and non-survivors. The temporal progression of fibrinogen, CRP and NLR is affected by dexamethasone treatment.