Search Results (84)

Background and Objectives: Coronavirus Disease 2019 (COVID-19) may cause extensive multi-organ pathology, particularly in the lungs, heart, kidneys, and liver. While hypercoagulability—often signaled by elevated D-dimer—has been thoroughly investigated, the concurrent pathological findings across organs and their interrelation with distinct D-dimer levels remain incompletely characterized. This study aimed to evaluate the pathological changes observed in autopsied or deceased COVID-19 patients, focusing on the prevalence of organ-specific lesions, and to perform subgroup analyses based on three D-dimer categories. Methods: We conducted a retrospective review of 69 COVID-19 patients from a Romanian-language dataset, translating all clinical and pathological descriptions into English. Pathological findings (pulmonary microthrombi, bronchopneumonia, myocardial fibrosis, hepatic steatosis, and renal tubular necrosis) were cataloged. Patients were grouped into three categories by admission D-dimer: <500 ng/mL, 500–2000 ng/mL, and ≥2000 ng/mL. Laboratory parameters (C-reactive protein, fibrinogen, and erythrocyte sedimentation rate) and clinical outcomes (intensive care unit [ICU] admission, mechanical ventilation, and mortality) were also recorded. Intergroup comparisons were performed with chi-square tests for categorical data and one-way ANOVA or the Kruskal–Wallis test for continuous data. Results: Marked organ pathology was significantly more frequent in the highest D-dimer group (≥2000 ng/mL). Pulmonary microthrombi and bronchopneumonia increased stepwise across ascending D-dimer strata (p < 0.05). Myocardial and renal lesions similarly showed higher prevalence in patients with elevated D-dimer. Correlation analysis revealed that severe lung and heart pathologies were strongly associated with high inflammatory markers and a greater risk of ICU admission and mortality. Conclusions: Our findings underscore that COVID-19-related organ damage is magnified in patients with significantly elevated D-dimer. By integrating pathology reports with clinical and laboratory data, we highlight the prognostic role of hypercoagulability and systemic inflammation in the pathogenesis of multi-organ complications. Stratifying patients by D-dimer may inform more tailored management strategies, particularly in those at highest risk of severe pathology and adverse clinical outcomes. Full article

Background: Oncocytoma and angiomyolipoma (AML) are benign renal tumors that may mimic malignant lesions on imaging. With the increasing use of partial nephrectomy (PN) for renal masses, accurate preoperative characterization of these lesions is essential. This study highlights the role of partial nephrectomy as a valuable diagnostic tool in situations where imaging is inconclusive or raises concern for malignancy without definitive confirmation. In the absence of a reliable preoperative diagnosis, partial nephrectomy provides direct histologic verification with minimal perioperative morbidity. Moreover, it offers curative potential when malignancy is present. By achieving both diagnostic certainty and renal preservation, this approach is well-suited for clinical scenarios in which imaging ambiguity might otherwise result in overtreatment through radical surgery or undertreatment Material and methods: in this retrospective study, we reviewed our 5-year experience (2019–2024), 188 partial nephrectomies—including bilateral procedures and operations on solitary kidneys—using robotic and open approaches. All of these 30 tumors were solid renal masses with indeterminate imaging features or suspicious characteristics suggestive of malignancy, further underscoring the limitations of current preoperative diagnostic modalities. Results: Histopathological evaluation confirmed benign renal tumors in 30 cases, with oncocytoma diagnosed in 18 cases (16 robotic, 2 open) and AML in 12 cases (9 robotic, 3 open). Conclusions: Even when imaging raises suspicion of malignancy or remains inconclusive, many small renal masses are ultimately confirmed as benign upon histopathological examination. This study underscores the diagnostic uncertainty associated with small renal tumors and highlights the value of partial nephrectomy as a decisive diagnostic intervention. In situations where non-invasive modalities fail to provide definitive answers, partial nephrectomy offers tissue confirmation with minimal morbidity. Furthermore, when malignancy is present, this approach ensures appropriate oncologic management while preserving renal function. Our findings support the integration of this strategy into routine clinical practice, particularly when diagnostic clarity is essential for guiding safe and effective treatment. Full article

A 10-year-old intact female Bichon Frise presented with multiple firm skin nodules on all four limbs. The nodules progressively increased in number and size over seven months. Diagnostic tests included cytology of fine-needle aspirates, histopathology of skin biopsies, radiography, and abdominal ultrasonography. Cytology revealed spindle-shaped mesenchymal cells and extracellular matrix components, and histopathology confirmed ND characterized by mature collagen deposition without evidence of malignancy. Ultrasonography detected multiple kidney cysts bilaterally, although their exact nature (benign or malignant) could not be confirmed histologically. Genetic analysis was performed, revealing no mutation in the traditionally implicated FLCN gene but multiple nonsynonymous mutations in the BRCA2 gene. This case suggests a potential association between BRCA2 gene mutations and the development of ND with renal cystic lesions, broadening the known genetic causes beyond the commonly reported FLCN mutation. Regular genetic screening and close monitoring of dermatological and renal conditions in atypical breeds are recommended. To the best of current knowledge, this is the first case report demonstrating ND and renal cysts associated with BRCA2 mutations in a Bichon Frise. Full article

Combretum micranthum G. Don (kinkeliba) is a medicinal plant traditionally employed in West Africa for its diuretic and gastrointestinal therapeutic properties. Despite its extensive ethnomedicinal use, comprehensive toxicological assessments are still lacking. This study aimed to characterize the phenolic composition of C. micranthum ethanolic leaf extract using HPLC-DAD-ESI-MS and evaluate its acute and subacute oral toxicity in BALB/c mice, per OECD Guideline 420. Female mice received oral doses of 50, 300, and 2000 mg/kg of extract for acute toxicity assessment for 14 days. In the subacute study, both sexes were administered daily doses at the same concentrations over 28 days. Clinical signs, body weight, and food and water consumption were regularly monitored throughout both protocols. At the end of each study, hematological, biochemical, and histopathological parameters were analyzed. Phenolic profiling revealed nine major compounds with a total of 293.54 mg/g extract. No mortality or significant clinical manifestations were observed at any dose. However, significant variations in platelet counts and amylase activity were noted in the acute phase. In the subacute model, slight, non-critical alterations in hepatic and renal biomarkers were observed, without signs of systemic toxicity. Histopathological examination revealed similar lesions in both acute and subacute phases, including multifocal inflammatory infiltrates (lymphocytes and neutrophils) in the periportal area of the liver, minimal bacterial overgrowth in the superficial layer of the gastric mucosa, minimal medullary mineralization and inflammatory infiltrates with lymphocytes in the kidneys, and minimal to moderate vacuolization in the pancreatic acini. These results indicate that C. micranthum ethanolic extract is relatively safe at the tested doses, reinforcing its traditional use and supporting further research into its pharmacological potential. Full article

Background: Essential thrombocythemia (ET) is a myeloproliferative neoplasm characterized by the uncontrolled proliferation of megakaryocytes and sustained thrombocytosis. Although its impact on renal function is not well established, a few case reports have described glomerular involvement and associated kidney impairment. Case Report: We present the case of a 79-year-old man with ET and stage 3b/A2 chronic kidney disease (CKD), who was admitted with severe acute kidney injury (AKI). This episode was associated with a progressive rise in platelet count, reaching 1,350,000/μL after discontinuation of anagrelide and loop diuretics. Renal biopsy (RB) revealed structural lesions compatible with a myeloproliferative neoplasm, including acute tubular necrosis (ATN), glomerulomegaly, and thrombotic microangiopathy (TMA). Cytoreductive therapy with hydroxyurea and corticosteroids was initiated, resulting in improvement of renal function and achievement of complete hematologic remission. Discussion: During follow-up, a linear correlation was observed between increasing platelet counts and declining renal function, underscoring the need for dynamic therapeutic adjustment and close monitoring to prevent progression to end-stage renal disease (ESRD). Conclusions: This case highlights the importance of nephrological evaluation in patients with ET and supports the role of cytoreductive therapy in managing ET-associated renal complications. Full article

Antiphospholipid syndrome (APS) can affect the kidneys, leading to renal artery and vein thrombosis, allograft loss following transplantation, and microvascular damage referred to as aPL-nephropathy (aPL-N). APL-N is a complex and frequently underdiagnosed condition characterized by an incomplete understanding of its etiopathogenesis and associated with unfavorable renal outcomes. The 2023 ACR/EULAR classification criteria for APS included aPL-N within the microvascular domain. The gold standard for aPL-N is the biopsy, revealing lesions associated with acute thrombotic microangiopathy and chronic vascular changes. Nevertheless, reluctance for biopsies due to anticoagulation and thrombocytopenia underscores the need for noninvasive diagnostics. Common clinical features include hypertension, microscopic hematuria, proteinuria, and renal insufficiency. Antiphospholipid antibodies seem crucial to kidney damage through thrombotic and inflammatory processes. Studies and experimental models of thrombotic microangiopathy lesions suggest the involvement of the complement cascade, tissue factor, and mammalian target of the rapamycin complex activation pathway. Currently, the management of aPL-N is based mainly on expert opinion, with limited evidence supporting the use of anticoagulants, leading to controversy in their application. Treatment may include heparin, intravenous immunoglobulin, plasma exchange, and targeted therapies tailored to aPL-N mechanisms. Future multicenter studies are essential to clarify their roles. The goal of this review is to inform clinicians and create a research agenda to address the unmet needs in diagnosing and managing APL-N. Full article

Background/Objectives: Calciphylaxis or calcific uremic arteriolopathy is a rare but highly lethal pathology that occurs most frequently in a uremic context, although it can also occur outside of this context. It is characterized by the appearance of necrotic skin lesions. Localization to the upper limbs is rare and has a similarly progressive evolution. Methods: We present a series of two cases—a male and a female—with calciphylaxis diagnoses (including biopsies) and with the patients undergoing dialysis for end-stage renal disease, both with infected and extensive necrotic lesions to the hands and fingers. Both cases required serial debridement treatments and amputations. A literature review was conducted using the precise search terms “calciphylaxis”, “upper limb”, “uremic calcific arteriolopathy”, and “end-stage renal disease” from January 2010 to May 2024. Results: One of the two reported cases ended with the patient’s death. The results of the literature review (comprising seven similar cases) confirmed the rarity of calciphylaxis lesion localization to the upper limbs and the high mortality rate among these patients despite administered treatments. No therapeutic protocol for these cases was confirmed. Conclusions: The treatment of calciphylaxis cases is multidisciplinary. Although surgical intervention is controversial, it is necessary in some cases, sometimes serially. Localization to the thoracic limbs has the same evolution and poor prognosis as other localizations. A standardized therapeutic protocol for these cases is still far from being established. Full article

Spondyloarthropathies (SpAs) represent a diverse group of seronegative immune-mediated inflammatory diseases characterized by a genetic predisposition and an association with human leukocyte antigen-B27. This narrative review aims to explore juvenile spondyloarthropathies (JSpAs), their classification, clinical manifestations, diagnostic challenges, and contemporary treatment strategies. According to the International League of Associations for Rheumatology criteria, JSpAs include several specific forms: enthesitis-related arthritis, psoriatic arthritis, and undifferentiated arthritis. Despite established classifications, the terms and definitions surrounding these conditions can often lead to confusion among healthcare professionals. This ambiguity underscores the need for a standardized approach to nosological classification. The clinical presentation of JSpAs can be multifaceted, encompassing both articular and extra-articular manifestations. Articular symptoms may include enthesitis and varying forms of arthritis, while extra-articular involvement can range from uveitis to gastrointestinal, cardiovascular, pulmonary, neurological, and renal complications. These diverse manifestations highlight the systemic nature of the disease and the importance of a holistic approach to diagnosis and treatment. While laboratory tests for SpAs are often non-specific, imaging modalities such as musculoskeletal ultrasound and magnetic resonance imaging play a crucial role in the early detection of inflammatory lesions. These imaging techniques can provide valuable insights into disease progression and aid in the formulation of appropriate treatment plans. Current treatment guidelines advocate for a “stepwise” approach to therapy, beginning with nonsteroidal anti-inflammatory drugs and progressing to glucocorticoids, disease-modifying antirheumatic drugs, and biological agents, particularly anti-tumor necrosis factor alpha agents. The primary objective of treatment is to achieve clinical remission or, at a minimum, to attain low disease activity. Regular monitoring of disease activity is imperative; however, the lack of validated assessment tools for the pediatric population remains a significant challenge. JSpAs pose unique challenges in terms of diagnosis and management due to their diverse manifestations and the complexities of their classification. Ongoing research and clinical efforts are essential to refine our understanding of these conditions, improve treatment outcomes, and enhance quality of life for affected children and their families. Effective management hinges on early detection, individualized treatment plans, and continuous monitoring, ensuring that patients receive the most appropriate care tailored to their specific needs. Full article

Introduction: Tuberous sclerosis complex (TSC) is a rare multisystemic genetic disorder characterized by the formation of benign tumors in various organs, including the central nervous system, skin, kidneys, and heart. The diagnosis is based on well-defined clinical criteria, such as those from Schwartz (2007) updated in 2012 by the International Tuberous Sclerosis Complex Consensus Group. The study aims to investigate the clinical, imaging, and molecular characteristics of patients diagnosed with tuberous sclerosis and to explore the correlation between specific genetic mutations (TSC1 and TSC2 genes) and the severity of clinical manifestations. Material and Methods: This is a retrospective longitudinal study of 13 patients diagnosed with tuberous sclerosis, identified in the records of the Bihor Regional Center for Medical Genetics (BRCMG) within the Bihor County Emergency Clinical Hospital from 1984 to 2024. Clinical, imaging, and molecular features were assessed. Patients were evaluated by a multidisciplinary team, including a geneticist, pediatrician, neurologist, psychiatrist, and psychologist. Clinical and imaging data were retrospectively collected from the congenital malformations and genetic disease records of BRCMG Bihor and statistically analyzed. Results: All patients showed clinical and imaging signs consistent with the diagnosis of tuberous sclerosis. Neurological manifestations were present in 83% of patients, including epilepsy and cognitive delays. Renal lesions were detected in 46% of cases, and dermatological lesions, such as facial angiofibromas, were observed in 69% of patients. Mutational variants identified in the TSC2 gene correlated with a more severe clinical presentation, including severe intellectual disability and treatment-resistant seizures, compared to variants in the TSC1 gene. Conclusions: Our study, although involving a small number of patients, highlights the clinical heterogeneity of tuberous sclerosis and the importance of a multidisciplinary approach in patient management. Early diagnosis and ongoing monitoring are essential to improving the quality of life for patients. Further studies are needed to assess the impact of therapeutic interventions and genetic correlations within the studied population. Full article

Background: Advancements in artificial intelligence (AI) diagnostics for renal cell carcinoma (RCC) provide valuable information for classification and subtyping, which improve treatment options and patient care. RCC diagnoses are most commonly incidental due to a lack of specific characterizations of subtypes, often leading to overtreatment. Accurate diagnosis also allows for personalized patient management. Different diagnostic methods, such as histopathology, multi-omics, imaging, and perioperative diagnostics, show a lot of promise for AI. Objective: This literature review focuses on developments in RCC diagnostics and their outcomes, efficacy, and accuracy in classification. Method: We conducted a non-systematic review of the published literature to explore advancements in the diagnostics of RCC. The PubMed and Google Scholar databases were reviewed to extract relevant information. The literature shows that AI can help distinguish RCC from other kidney lesions and track tumor growth. The integration of radiomic features with clinical metadata further enhances the results. This enables clinicians to implement personalized treatment plans. The application of artificial intelligence in perioperative diagnostics enhances decision-making, improves patient safety, mitigates intraoperative complications, and accelerates recovery. Alongside the advancements in AI-assisted diagnostics, there are problems that need to be addressed, including selection bias, demand for larger and diverse datasets, and reliable validation. Conclusions: Despite the challenges, using AI to help with RCC diagnosis could lead to better patient outcomes, a new standard of care for RCC patients, and more personalized cancer management for each patient. Full article

Renal artery stenosis (RAS) is a vascular condition characterized by narrowing of one or both renal arteries, leading to reduced blood flow to the kidneys, activation of the renin–angiotensin–aldosterone system (RAAS), and subsequent renovascular hypertension. Overactivation of the same cascade potentiates the production of angiotensin II, which induces systemic vasoconstriction, increases sodium and water retention via aldosterone, and activates the sympathetic nervous system. Angiotensin II is also implicated in endothelial dysfunction, oxidative stress, and chronic inflammation, thus impairing vascular remodeling and arterial stiffness, all of which serve to accelerate cardiovascular complications, such as left ventricular hypertrophy, heart failure, and myocardial infarction. RAS is usually due in at least 90% of cases to atherosclerosis, which typically affects older people with diabetes and smoking as risk factors. There are two types of RAS: unilateral and bilateral. Bilateral RAS is commonly associated with flash pulmonary edema, a life-threatening emergency condition in which alveolar space flooding can occur within minutes. RAS typically remains asymptomatic until the late stage with complications of hypertension, ischemic nephropathy, or chronic kidney disease. FMD tends to create structural abnormalities of the artery, whereas atherosclerosis causes plaque formation and endothelial dysfunction of the artery. Epidemiological surveys have revealed that the prevalence of RAS ranges from 4% to 53% and is especially high among patients with hypertension, cardiovascular disease, or CKD. Diagnosis is based on clinical suspicion and supported by imaging studies, including Doppler ultrasound, computed tomography angiography, and magnetic resonance angiography. Early detection also relies on certain laboratory biomarkers, especially in identifying high-risk patients. These markers would include increased plasma renin activity, elevated aldosterone-renin ratio, and inflammatory markers, including C-reactive protein and endothelin-1. Treatment would also involve pharmacological approaches, including RAAS inhibitors, beta-blockers, and statins, and interventional treatments, including angioplasty and stenting in patients with severe forms of the disease. However, the Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) Trial showed that most patients would likely require medical therapy, and that intervention should be reserved for those with uncontrolled hypertension, progressive renal dysfunction, or recurrent episodes of pulmonary edema. Other emerging therapies include drug-eluting balloons, bioresorbable stents, and gene-editing techniques, all of which have shown great promise in the few studies that have been conducted, although further evaluation is needed. Despite these advances, there are still gaps in knowledge regarding patient stratification, biomarker validation, and the development of personalized treatment strategies. This article reviews the complexities of RAAS and its systemic impact on cardiovascular and renal health. Future research can therefore focus on improving early diagnosis, optimizing patient selection for intervention, and developing new therapies to slow disease progression and mitigate complications. Full article

Feline infectious peritonitis virus (FIPV) remains as one of the leading causes of morbidity and mortality in young cats from shelters and catteries worldwide. Since little is known about the molecular characteristics of currently circulating FIPV strains in Long Island, New York, samples from two shelter cats submitted to the Pathology Diagnostic Services of the Long Island University College of Veterinary Medicine, with gross and microscopic lesions consistent with those of FIP were processed for virus isolation, molecular characterization and full-length genome decoding. The younger shelter cat, a 1-year-old male (A15) was found dead without previous signs of illness. Postmortem examination revealed gross and microscopic lesions characterized by vasculitis, necrosis, hemorrhage, and pyogranulomatous inflammation confined to the colon and associated lymph nodes. The second cat, a 7-year-old spayed female (A37) had an identical clinical history and similar but widespread lesions, including fibrinous peritoneal effusion, cecal, colonic, renal, and hepatic involvement. The gross and microscopic diagnosis of FIP in these cats was confirmed by immunohistochemistry (IHC) demonstration of feline coronavirus antigen using mouse anti-FIPV3-70 monoclonal antibody. Virus isolation from saved frozen kidney and colon tissue was performed through several subsequent blind passages in MDCK and Vero cell lines. Confirmation of the FIPV isolation was done through qRT-PCR, IFA, western blot using N protein antibodies, and NGS of the full-length genome sequencing. The full-length genome sequences of the virus isolate from the two cats were decoded using next-generation sequencing (NGS) and deposited in the GenBank as accession numbers PQ192636 and PQ202302. The genome size of these isolates was (29355 and 29321) nucleotides (nt) in length, respectively. While their genome organization was consistent with other FIPV genomes as follows (5’UTR-ORF1ab-S-3abc-M-E-7b-3’UTR-3’), marked differential mutations were observed in the ORF1a/b, S, 3Abc, and 7b protein genes of the two FIPV isolates. One notable deletion of 34 nucleotides was observed in the 7b genes of one of these isolates but was absent in the other. We confirmed the potential recombination events during the evolution of those two FIPV field isolates with the potential parent virus as FECoV-US isolated in 1970 and the potential minor parent as the Canine coronavirus. Our results provide a comprehensive molecular analysis of two novel FIPV isolates causing fatal disease in shelter cats from Long Island. Diagnostic surveillance with molecular characterization and sequencing analysis of circulating FIPV strains within animal shelters may help early detect unique emerging clinical and pathological manifestations of the disease and develop more targeted prophylactic and therapeutic approaches to control it. Full article

Acquired reactive perforating dermatosis (ARPD) is characterized by its onset after the age of 18 years, umbilicated papules or nodules with a central keratotic plug, and the presence of necrotic collagen tissue within an epithelial crater. ARPD is strongly associated with systemic diseases such as diabetes mellitus (DM) and chronic renal failure, which may contribute to ARPD through factors including microcirculatory disturbances and the deposition of metabolic byproducts, including advanced glycation end-products and calcium. Here, we report a case of ARPD that improved following DM treatment and catheter-based interventions for peripheral artery disease (PAD). The eruptions on the upper limbs significantly improved with DM management. On the other hand, lesions on the lower limbs showed marked improvement after the enhancement in arterial blood flow due to catheter surgeries, along with DM treatment. Although a few reports of ARPD improving with DM management exist, our case underscores the importance of adequate DM control in ARPD management. The inability to perform the biopsy of the lesions on the lower limbs is our limitation; however, these lesions, similar to those on the upper limbs, presented with a central keratotic plug and re-epithelialized without forming ulcers or erosions, suggesting they were also related to ARPD. To date, there has been little discussion on the relationship between blood flow impairment in major vessels and ARPD. However, hypertension and venous circulatory dysfunctions are considered to lead to ARPD, raising the possibility that PAD-induced microvascular disturbances might have facilitated lesion formation in the present case. Further accumulation of cases and research is needed to clarify the relationship between blood flow impairment in major vessels and ARPD. Full article

Multiple myeloma (MM) is a malignant disease characterized by the proliferation of plasma cells, primarily in the bone marrow. It accounts for approximately 1% of all cancers and 10% of hematologic malignancies. Clinical manifestations include hypercalcemia, anemia, renal failure, and bone lesions. The pathogenesis of MM involves complex interactions between myeloma cells and their microenvironment. Galectins, a family of β-galactoside-binding proteins, particularly galectin-1, -3, -4, -7, and -9, have been implicated in MM development. This study aimed to assess the plasma levels of these galectins in newly diagnosed MM patients and explore their correlation with clinical parameters. Peripheral blood samples were collected from patients at the Oncohematology Service of the Hospital de Câncer de Pernambuco, and galectin levels were measured using ELISA. Plasma levels of galectins-3, -7, and -9 were significantly higher in MM patients compared to the control group. Three clusters of MM patients were identified based on galectin plasma levels, with cluster 3, characterized by high levels of galectin-1, -4, and -7, being associated with a worse prognosis. A strong positive correlation was found between galectin-1, -4, and -7 levels and markers of kidney function (urea, creatinine, and β2-microglobulin), while negative correlations were observed with hematocrit and hemoglobin. Additionally, galectin-9 showed high accuracy in distinguishing MM patients from healthy controls (AUC = 0.931). Elevated galectin levels were indicative of disease aggressiveness and renal impairment in MM patients. Overall, our findings suggest that galectins-1, -4, -7, and -9 could serve as potential biomarkers for MM progression and severity, warranting further investigation into their utility in MM diagnosis and treatment. Full article

Background: Lupus podocytopathy (LP) is a non-immune complex-mediated glomerular lesion in systemic lupus erythematosus (SLE), characterized by the diffuse effacement of podocyte processes without immune complex deposition or with only mesangial immune complex deposition. LP is a rare cause of nephrotic syndrome in SLE patients with implications for prognosis and treatment. Case Report: We present the case of a 28-year-old woman with a medical history of type 1 diabetes mellitus (T1DM) who presented with lower limb edema, dyspnea, hypercholesterolemia, with nephrotic range proteinuria, without acute kidney injury, and laboratory findings compatible with auto-immune hemolytic anemia. They had negative infectious serology, positive antinuclear antibody (ANA), and an eye fundus examination showing diabetic retinopathy. A biopsy was performed to define the etiology of the renal involvement, which was compatible with LP. Following immuno-suppressive and antiproteinuric therapy, the patient evolved with the complete remission of the nephrotic syndrome. Conclusions: Lupus podocytopathy is an infrequent anatomopathological entity, so this case is presented as the first reported in Peru, and a literature review is made. Full article