Polycystic ovary syndrome (PCOS) is a complex disorder with heterogenous phenotypes and unclear etiology. A recent phenotypic clustering study identified metabolic and reproductive subtypes of PCOS. We hypothesize that the heterogeneity of PCOS manif...
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder in which patients present inattention, hyperactivity, and impulsivity. The etiology of this condition is diverse, including environmental factors and the presence of var...
The etiological diagnosis of diabetes conveys many practical consequences for the care of patients, and often of their families. However, a wide heterogeneity in the phenotypes of all diabetes subtypes, including Type 1 diabetes, Type 2 diabetes, and...
Hepatic steatosis can occur in lean individuals, while its metabolic and risk profiles remain unclear. We aimed to characterize the clinical and risk profiles of lean and non-lean steatosis. This cross-sectional study included 1610 patients with tran...
Molecular pathologic diagnosis is important in clinical (oncology) practice. Integration of molecular pathology into epidemiological methods (i.e., molecular pathological epidemiology) allows for investigating the distinct etiology of disease subtype...
Background and Objectives: Hepatocellular carcinoma (HCC), the most common type of primary liver cancer, is the leading cause of cancer-related mortality. It arises and progresses against fibrotic or cirrhotic backgrounds mainly due to infection with...
Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is considered to be associated with post-viral complications and mental stress, but the role of autoimmunity also remains promising. A comparison of autoimmune profiles in chronic fatigue of...
Recent next-generation sequencing (NGS) studies on large cohorts of cholangiocarcinoma (CCA) patients have clearly revealed the extreme intra- and inter-tumoral molecular heterogeneity that characterizes this malignancy. The lack of a stereotyped mol...
The etiology of oculo–auriculo–vertebral spectrum (OAVS) is not well established. About half of patients show a positive family history. The etiology of familiar cases is unclear but appears genetically heterogeneous. This motivated us to...
Sarcoidosis is a heterogeneous multisystem granulomatous disease of unknown etiology [...]
Background/Objectives: Trochlear nerve palsy (TNP) is a clinically significant neuro-ophthalmic disorder with a broad and heterogeneous etiologic spectrum. Due to the trochlear nerve (TN)’s long intracranial course and its proximity to key neur...
Rheumatoid arthritis (RA) is a progressive and inflammatory autoimmune disease that displays high heterogeneity in etiology, clinical presentation, prognosis, and response to therapy [...]
The term “cheilitis” refers to an inflammatory condition of the lip and encompasses an heterogeneous group of lesions of different etiology, clinical aspects, management and prognosis [...]
Platelet-rich fibrin (PRF) consists of a matrix that provides the necessary elements for wound healing, acting as a biodegradable scaffold for cell migration, proliferation, and differentiation, in addition to the delivery of growth factors and angio...
The human neural tube defects (NTD), anencephaly, spina bifida and craniorachischisis, originate from a failure of the embryonic neural tube to close. Human NTD are relatively common and both complex and heterogeneous in genetic origin, but the genet...
Out-of-hospital cardiac arrest (OHCA) is heterogeneous in terms of etiology and severity. Owing to this heterogeneity, differences in outcome and treatment efficacy have been reported from case to case; however, few reviews have focused on the hetero...
Ovarian high-grade serous carcinomas (HGSCs) are a heterogeneous group of diseases. They include fallopian-tube-epithelium (FTE)-derived and ovarian-surface-epithelium (OSE)-derived tumors. The risk/protective factors suggest that the etiology of HGS...
The correct recognition of the etiology of ischemic stroke (IS) allows tempestive interventions in therapy with the aim of treating the cause and preventing a new cerebral ischemic event. Nevertheless, the identification of the cause is often challen...
Background: Cholangiocarcinoma (CCA) is a highly heterogeneous malignancy arising from the biliary epithelium, with an increasing incidence and poor prognosis worldwide. Recent advances in next-generation sequencing have revealed a variety of genomic...
Background/Objectives: Schizophrenia is a clinically heterogeneous complex disorder with a substantial polygenic basis. The discovery of phenotypes indexing genetic differences advances research into the schizophrenia etiology but has proven to be ch...
Background: Premature ovarian insufficiency (POI) is a complex and heterogeneous condition affecting women of reproductive age. Historically, most POI cases have been classified as idiopathic due to limited diagnostic capabilities. However, due to th...
Congenital microcephaly causes smaller than average head circumference relative to age, sex and ethnicity and is most usually associated with a variety of neurodevelopmental disorders. The underlying etiology is highly heterogeneous and can be either...
Recurrent pregnancy loss is a complex health challenge with no universally accepted definition. Inconsistency in definitions involves not only the number of spontaneous abortions (two or three) that are accepted for recurrent pregnancy loss but the t...
Diabetic retinopathy (DR) is a common sight-threatening complication of diabetes. Overall, 26% of the 37 million Americans with diabetes suffer from DR, and 5% of people with diabetes suffer from vision-threatening DR. DR is a heterogeneous disease;...
Cardiomyopathy (CMP) is a rare disease in the pediatric population, with a high risk of morbidity and mortality. The genetic etiology of CMPs in children is extremely heterogenous. These two factors play a major role in the difficulties of establishi...
Myocarditis is a non-ischemic condition with a heterogeneous etiology, clinical course and prognosis. The most common etiology of myocarditis are viral infections, whereas the most severe complications are acute and chronic heart failure and sudden c...
Background: Fever of unknown origin (FUO) in children remains a diagnostic challenge due to heterogeneous etiologies. This study investigated the etiological distribution, long-term outcomes of undefined cases, and laboratory predictors that differen...
Background/Objectives: Congenital microcephaly is a clinical manifestation with a heterogeneous etiology, and its epidemiological surveillance relies on the systematic identification of cases and investigation of their underlying causes to inform pre...
Preeclampsia is a multisystem disorder that develops during pregnancy and is associated with severe complications for both the pregnant woman and her infant. It remains a leading cause of maternal and perinatal mortality and morbidity. Although it af...
The etiology of obesity is complex and idiosyncratic—with inherited, behavioral, and environmental factors determining the age and rate at which excessive adiposity develops. Moreover, the etiologic status of an obese phenotype (how and when it...
Background and Objectives: Acute hematologic malignancies are a group of heterogeneous blood diseases with a high mortality rate, mostly due to acute respiratory failure (ARF). Acute respiratory distress syndrome (ARDS) is one form of ARF which repre...
Chromosome instability (CIN) is defined as an increased rate of chromosome gains and losses that manifests as cell-to-cell karyotypic heterogeneity and drives cancer initiation and evolution. Current research efforts are aimed at identifying the etio...
Myocarditis is an inflammatory disease of the myocardium caused by infectious or non-infectious agents. It can lead to serious short-term and long-term sequalae, such as sudden cardiac death or dilated cardiomyopathy. Due to its heterogenous clinical...
Bronchiectasis is the third leading chronic inflammatory disease of the airway caused by dozens of pulmonary and extra-pulmonary diseases. Infection by pathogenic microorganisms is very common. We aimed to analyze, for the first time in the literatur...
Postural Orthostatic Tachycardia Syndrome (POTS) affects up to 1% of the US population, predominantly women, and is characterized by a complex, elusive etiology and heterogeneous phenotypes. This review delves into the intricate physiology and etiolo...
Background: The prevalence of neural autoantibodies in epilepsy of unknown etiology varies among studies. We aimed to conduct a systematic review and meta-analysis to determine the pooled global prevalence and the prevalence for each antibody. Method...
Background/Objectives: Severe thrombocytopenia (platelet count ≤ 50,000/µL) is a diagnostically heterogeneous condition during pregnancy, encompassing obstetric and non-obstetric etiologies that require distinct management approaches. The ai...
Hepatocellular carcinoma (HCC) represents a global health problem. The incidence keeps increasing and current therapeutic options confer limited benefits to the patients. Tumor heterogeneity plays a central role in this context, limiting the availabi...
Chronic kidney disease (CKD) remains a global health burden, with limited therapeutic options that effectively target the underlying pathophysiology. Nuclear factor erythroid 2-related factor 2 (NRF2), a key regulator of oxidative stress and inflamma...
Myocarditis is an inflammatory disease of the myocardium with heterogeneous etiology, clinical presentation, and prognosis; when it is associated with myocardial dysfunction, this identifies the entity of inflammatory cardiomyopathy. In the last few...
Vitiligo is an autoimmune complex pigmentation disease characterized by non-pigmented patches on the surface of the skin that affect approximately 0.5–2% population worldwide. The exact etiology is still unknown; however, vitiligo is hypothesiz...
Postcholecystectomy syndrome (PCS) comprises a heterogeneous group of symptoms and disorders in patients who have previously undergone cholecystectomy. While it is relatively uncommon, it is defined by chronic recurring pain, often with no clear sour...
Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of reproductive age. Its heterogeneous clinical presentation is characterized by hyperandrogenemia, reproductive changes, polycystic ovary morphology, and i...
Infantile spasms (IS) is an epileptic encephalopathy with unique clinical and electrographic features, which affects children in the middle of the first year of life. The pathophysiology of IS remains incompletely understood, despite the heterogeneit...
Amelogenesis imperfecta (AI) is a heterogeneous group of rare genetic disorders affecting amelogenesis during dental development. Therefore, the molecular genetic etiology of AI can provide information about the nature and progress of the disease. To...
More than half of patients affected by cancer experience pain of moderate-to-severe intensity, often in multiple sites, and of different etiologies and underlying mechanisms. The heterogeneity of pain mechanisms is expressed with the fluctuating natu...
Introduction: Refractory Status Epilepsy Syndrome is a heterogeneous group of diseases associated with status epilepsy. Literature and definition have been conflicting and confusing in terms of their nomenclatures. New-onset refractory status epilept...
Sarcoidosis is a complex granulomatous disease of unknown etiology. Due to the heterogeneity of the disease, the diagnosis remains challenging in many cases, often at the physician’s discretion, requiring a thorough and complex investigation. M...
Tremor, an oscillatory movement disorder, is commonly encountered in clinical practice in the setting of a variety of etiologies, such as essential tremor and Parkinson’s disease. Despite its high prevalence, treatment options are somewhat limi...
Women are known to have particular heterogeneity in stroke etiology related to childbearing and hormonal factors. Although there are continued acute stroke treatment advances focusing on clot dissolution or extraction, effective secondary prevention...
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