Disease and Detection of Disease

Sarvarthapedia

Sarvarthapedia (Core Areas)

Volume 1: Foundations of Disease – Concepts, History, and Taxonomy

Part I: Defining Disease

• Disease vs. illness vs. syndrome
• Natural history of disease (pre-pathogenesis, latent, symptomatic, resolution)
• Classification systems: ICD-11 (2022 revision), SNOMED CT, MeSH
• The exposome and disease origins

Part II: Historical Milestones in Disease Detection (Antiquity–1950)

• Ancient Egyptian, Chinese, and Greek medicine (Hippocratic humors, pulse diagnosis)
• Invention of the stethoscope (Laënnec, 1816)
• Germ theory (Pasteur, Koch) and its impact on diagnostics
• First clinical laboratories (19th century)
• Discovery of X-rays (Röntgen, 1895)
• Blood typing and cross-matching (Landsteiner, 1901)
• Electrocardiograph (Einthoven, 1903)

Part III: Modern Era of Detection (1950–2020)

• Electron microscopy
• Radioimmunoassay (Yalow & Berson)
• ELISA and Western blot
• PCR invention (Mullis, 1983)
• Flow cytometry
• Sanger sequencing

Part IV: Epidemiology and Screening Principles

• Sensitivity, specificity, predictive values
• ROC curves
• Lead time and length time bias
• Wilson-Jungner criteria for screening
• Overdiagnosis and false positives

Part V: Ethical and Legal Frameworks

• Informed consent in diagnostic testing
• Genetic information non-discrimination acts
• Data privacy (HIPAA, GDPR in diagnostics)

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Volume 2: Molecular and Genomic Foundations of Disease Detection

Part I: The Human Genome and Disease

• From Watson-Crick to T2T genome (2022 complete assembly)
• Types of genetic variation (SNPs, indels, CNVs, STRs)
• Mendelian disorders vs. complex traits
• Epigenetics (DNA methylation, histone modification, non-coding RNAs)

Part II: Nucleic Acid-Based Detection

• PCR variants: qPCR, RT-PCR, digital droplet PCR, multiplex PCR
• Isothermal amplification (LAMP, RPA, NASBA)
• CRISPR-based diagnostics (SHERLOCK, DETECTR, 2020–2025 refinements)
• Next-generation sequencing (NGS): whole genome, exome, targeted panels
• Third-generation sequencing (PacBio, Oxford Nanopore)
• Liquid biopsy: circulating tumor DNA, fetal DNA, microbial cell-free DNA

Part III: Protein and Metabolite Detection

• Mass spectrometry (MALDI-TOF, LC-MS/MS)
• Proximity extension assay and Olink technology
• Aptamer-based proteomics (SOMAscan)
• Metabolomics in early disease detection (diabetes, cancer, inborn errors)

Part IV: Single-Cell and Spatial Technologies

• Single-cell RNA-seq
• Spatial transcriptomics (Visium, MERFISH)
• Imaging mass cytometry

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Volume 3: Imaging and Structural Diagnostics

Part I: Radiography and Fluoroscopy

• Digital radiography (DR), computed radiography (CR)
• Contrast agents (iodinated, barium)
• Dual-energy X-ray absorptiometry (DXA)

Part II: Computed Tomography (CT)

• Helical, multi-detector, cone-beam CT
• Dual-energy CT, photon-counting CT (approved 2021–2023)
• CT angiography, perfusion CT
• Low-dose protocols and AI reconstruction

Part III: Magnetic Resonance Imaging (MRI)

• Physics (T1, T2, proton density, diffusion, perfusion)
• Functional MRI (BOLD)
• MR spectroscopy, MR elastography
• 7 Tesla and ultra-high-field MRI (clinical adoption 2020–2025)
• Gadolinium-free contrast agents

Part IV: Ultrasound

• B-mode, M-mode, Doppler (color, power, spectral)
• Contrast-enhanced ultrasound (microbubbles)
• Elastography (shear wave, strain)
• Point-of-care ultrasound (POCUS)

Part V: Nuclear Medicine

• PET: FDG and novel tracers (PSMA, DOTATATE, amyloid, tau)
• SPECT (Tc-99m, I-123)
• Hybrid imaging: PET/CT, PET/MRI, SPECT/CT
• Theranostics (e.g., Lu-177 PSMA, 2024 updates)

Part VI: Emerging Optical and Hybrid Imaging

• Optical coherence tomography (OCT)
• Photoacoustic imaging
• Fluorescence lifetime imaging (FLIM)
• Multispectral optoacoustic tomography (MSOT)

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Volume 4: Laboratory Medicine – Hematology, Chemistry, and Immunology

Part I: Hematologic Disease Detection

• Complete blood count (CBC) parameters and flags
• Peripheral smear and automated morphology (AI-based)
• Bone marrow aspiration and biopsy
• Coagulation assays (PT, aPTT, thrombin time, D-dimer, thromboelastography)
• Hemoglobin electrophoresis and HPLC
• Flow cytometry for leukemia/lymphoma immunophenotyping

Part II: Clinical Chemistry

• Electrolytes, renal function (creatinine, cystatin C, eGFR)
• Liver panel (ALT, AST, ALP, GGT, bilirubin, albumin)
• Cardiac biomarkers (troponin I/T, BNP/NT-proBNP, CK-MB)
• Pancreatic enzymes (amylase, lipase)
• Therapeutic drug monitoring and toxicology screens

Part III: Immunology and Serology

• Autoantibody panels (ANA, anti-dsDNA, RF, anti-CCP, ANCA)
• Complement assays (CH50, C3, C4)
• Acute phase reactants (CRP, ESR, procalcitonin, SAA)
• Immunoglobulin quantification and subclasses
• Serum protein electrophoresis and immunofixation

Part IV: Point-of-Care Testing (POCT)

• Glucose, HbA1c, lipid panels
• Rapid infectious disease tests (COVID-19, influenza, RSV, Strep A, HIV)
• Pregnancy and fertility tests
• Coagulation POCT (INR)
• Emerging wearable biosensors (2020–2026)

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Volume 5: Infectious Disease Detection

Part I: Bacterial Pathogens

• Conventional culture and sensitivity (automated systems: VITEK, BD Phoenix)
• MALDI-TOF for bacterial ID
• Molecular diagnostics (multiplex panels: BioFire, QIAstat-Dx)
• Antibiotic resistance detection (MRSA, VRE, CRE, carbapenemases)
• Whole-genome sequencing for outbreak tracking

Part II: Viral Diagnostics

• Antigen detection (rapid tests, immunofluorescence)
• Serology (IgM/IgG, neutralization assays)
• Nucleic acid amplification tests (NAAT)
• Viral load quantification (HIV, HBV, HCV, CMV, EBV)
• Next-generation sequencing for novel viruses (metagenomics)

Part III: Fungal and Parasitic Diseases

• Microscopy (KOH, calcofluor white, Giemsa, trichrome)
• Fungal culture and antifungal susceptibility
• Antigen detection (Galactomannan, β-D-glucan, Cryptococcal antigen)
• Molecular panels for malaria, leishmaniasis, trypanosomes
• Multiplex PCR for intestinal parasites

Part IV: Emerging and Zoonotic Infections

• COVID-19 diagnostics (PCR, antigen, serology, 2020–2025 variants)
• Mpox, Ebola, Marburg, Lassa fever diagnostics
• Avian influenza, Nipah, Zika, Chikungunya
• Biosafety levels and laboratory-acquired infections

Part V: Sepsis and Syndromic Panels

• Procalcitonin and host-response biomarkers
• Rapid pathogen identification from blood (T2MR, SeptiCyte)
• Metagenomic NGS for culture-negative sepsis

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Volume 6: Cancer Detection and Oncologic Diagnostics

Part I: Traditional Cancer Diagnostics

• Histopathology and cytology (Pap smear, FNA, effusion cytology)
• Immunohistochemistry (IHC) panels (CK, EMA, CD markers, hormone receptors)
• Frozen section vs. permanent section

Part II: Molecular Oncology

• Somatic mutation testing (EGFR, KRAS, BRAF, IDH, PIK3CA)
• Gene fusions (FISH, RNA-seq) – ALK, ROS1, RET, NTRK
• Microsatellite instability (MSI) and mismatch repair deficiency
• Tumor mutational burden (TMB)
• Homologous recombination deficiency (HRD) and BRCA1/2

Part III: Liquid Biopsy in Oncology

• Circulating tumor cells (CTC) – CellSearch, microfluidics
• ctDNA – detection of minimal residual disease (Signatera, Guardant Reveal)
• Methylation-based early detection (Galleri, PanSeer)
• Extracellular vesicles (exosomes) as diagnostic cargo

Part IV: Cancer Screening Programs

• Low-dose CT for lung cancer
• Mammography, tomosynthesis, and breast MRI
• Colonoscopy, FIT, Cologuard (mt-sDNA)
• PSA and biomarkers for prostate (PHI, 4Kscore, SelectMDx)
• HPV testing and cervical screening
• Emerging: multi-cancer early detection (MCED) tests

Part V: Hematologic Malignancy Diagnostics

• Immunophenotyping (flow cytometry)
• Cytogenetics (karyotype, FISH)
• Clonality assays (TCR/IGH gene rearrangements)
• NGS panels for myeloid/lymphoid neoplasms

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Volume 7: Cardiovascular, Respiratory, and Renal Disease Detection

Part I: Cardiovascular Diagnostics

• ECG (rest, stress, Holter, event monitor)
• Echocardiography (TTE, TEE, strain imaging, 3D)
• Cardiac MRI and CT coronary angiography
• Invasive hemodynamics and coronary angiography
• Biomarkers: troponin, BNP, CRP, galectin-3, sST2
• Genetic testing for cardiomyopathies and arrhythmias (LQT, Brugada)

Part II: Respiratory Disease Detection

• Spirometry and full PFTs (DLCO, lung volumes)
• Bronchoscopy (white light, autofluorescence, EBUS)
• Exhaled nitric oxide (FeNO) for asthma
• Imaging: HRCT for ILD, V/Q scan for PE
• Molecular testing for lung cancer (see Vol 6)
• Rapid diagnostics for pneumonia (urinary antigens, multiplex PCR)

Part III: Renal Disease Detection

• Urinalysis (dipstick, microscopy)
• Albumin-to-creatinine ratio (ACR)
• eGFR equations (CKD-EPI 2021 race-free)
• Renal biopsy (light, immunofluorescence, EM)
• Biomarkers of AKI (NGAL, KIM-1, TIMP-2 x IGFBP7)
• Autoantibodies in glomerulonephritis (anti-GBM, anti-PLA2R)

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Volume 8: Neurological and Psychiatric Disease Detection

Part I: Neuroimaging

• CT for acute stroke/hemorrhage
• MRI sequences (T1, T2, FLAIR, DWI, SWI, MRA, MRV)
• PET tracers: amyloid (Florbetapir), tau (Flortaucipir), FDG
• DaTscan for Parkinsonism

Part II: Neurophysiology

• EEG (routine, ambulatory, video-EEG, high-density)
• Evoked potentials (VEP, BAEP, SSEP)
• Electromyography (EMG) and nerve conduction studies (NCS)
• Polysomnography for sleep disorders

Part III: Cerebrospinal Fluid Analysis

• Cell count, protein, glucose, oligoclonal bands
• CSF biomarkers for Alzheimer’s (Aβ42, p-tau, t-tau, neurofilament light)
• Autoimmune encephalitis antibody panels
• PCR for neuroinfections (HSV, VZV, JCV, Lyme)

Part IV: Psychiatric Disease Detection

• Structured clinical interviews (SCID, MINI)
• Rating scales (HAM-D, MADRS, YMRS, PANSS, CGI)
• Biomarkers: inflammatory markers, BDNF, cortisol
• Neurocognitive testing (MoCA, MMSE, RBANS)
• Digital phenotyping (smartphone sensors, speech analysis)

Part V: Neuromuscular and Neurogenetic Disorders

• Genetic testing for Huntington’s, CMT, muscular dystrophies
• Muscle biopsy and histochemistry
• Skin biopsy for small fiber neuropathy

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Volume 9: Endocrine, Metabolic, and Autoimmune Disease Detection

Part I: Endocrine Diagnostics

• Thyroid: TSH, fT4, fT3, TPOAb, TgAb, TRAb, ultrasound, FNA
• Adrenal: cortisol (serum, saliva, urine), ACTH, aldosterone/renin, metanephrines
• Pituitary: GH/IGF-1, prolactin, ACTH, CRH stimulation, MRI
• Reproductive: LH, FSH, estradiol, testosterone, AMH, inhibin
• Diabetes: glucose, OGTT, HbA1c, C-peptide, autoantibodies (GAD, IA-2, ZnT8)

Part II: Metabolic Disease Detection (Metabolic Syndrome)

• Newborn screening (MS/MS for PKU, MCAD, MSUD, etc.)
• Lipid panel, apolipoproteins, Lp(a)
• Iron studies (ferritin, iron, TIBC, transferrin saturation)
• Porphyria testing (urine/blood porphyrins)
• Lysosomal storage disorders (enzyme assays, molecular)

Part III: Autoimmune Disease Detection

• Systemic lupus (ANA, anti-dsDNA, anti-Smith, complement, lupus anticoagulant)
• Rheumatoid arthritis (RF, anti-CCP, CRP, imaging: ultrasound, MRI)
• Scleroderma (anti-Scl-70, anti-centromere, nailfold capillaroscopy)
• Sjögren’s (anti-SSA/Ro, anti-SSB/La, labial biopsy)
• Antiphospholipid syndrome (lupus anticoagulant, anti-β2GPI, anticardiolipin)

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Volume 10: Pediatric, Genetic, and Rare Disease Detection

Part I: Prenatal and Neonatal Diagnostics

• Prenatal ultrasound (first-trimester NT scan, anomaly scan)
• Non-invasive prenatal testing (NIPT) for aneuploidies
• Chorionic villus sampling and amniocentesis (karyotype, microarray)
• Neonatal hearing screening (OAE, ABR)
• Critical congenital heart disease (pulse oximetry)

Part II: Inborn Errors of Metabolism (IEM)

• Urine organic acids, plasma amino acids, acylcarnitines
• Enzyme assays (fibroblasts, leukocytes)
• Molecular confirmation (targeted NGS, whole exome)

Part III: Rare Disease Diagnostics

• Whole exome and genome sequencing (first-line for undiagnosed)
• Long-read sequencing for repeat expansions (FMR1, DMPK, ATXN)
• RNA-seq for splice variants
• Functional assays (e.g., transferrin electrophoresis for CDG)
• International rare disease registries and matchmaking (Matchmaker Exchange)

Part IV: Developmental and Behavioral Pediatrics

• Dysmorphology exam and standardized checklists
• Developmental screening (ASQ, M-CHAT, PEDS)
• Genetic testing for intellectual disability (microarray, Fragile X, Rett, Angelman)

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Volume 11: Emerging Technologies and Future Directions (2020–2026)

Part I: Artificial Intelligence and Machine Learning

• AI in radiology (chest X-ray, mammography, CT, MRI segmentation)
• Deep learning for histopathology (tumor grading, mitosis detection)
• Digital pathology and whole-slide image analysis
• AI-assisted ECG interpretation (arrhythmia, LV dysfunction)
• Natural language processing for EHR-based phenotyping
• Regulatory approvals (FDA AI/ML-enabled devices up to 2026)

Part II: Wearable, Implantable, and Remote Sensing

• Continuous glucose monitors (Dexcom G7, Abbott Freestyle Libre 3)
• Smartwatches for atrial fibrillation detection (Apple Watch, Fitbit)
• Implantable loop recorders
• Sweat and tear-based biosensors
• Smart contact lenses for glaucoma and glucose

Part III: Multi-Omics Integration

• Proteomics, metabolomics, lipidomics, glycomics in early detection
• Integrative pan-cancer early detection (MCED) – clinical trials 2022–2025
• Microbiome as a diagnostic tool (gut, oral, skin)

Part IV: Lab-on-a-Chip and Microfluidics

• Organ-on-a-chip for disease modeling and drug testing
• Microfluidic PCR and immunoassays
• Paper-based diagnostics for low-resource settings

Part V: Regulatory, Economic, and Access Issues

• FDA Breakthrough Device designation
• Reimbursement challenges for NGS and MCED
• Global disparities in diagnostic access
• Telemedicine and remote diagnostics (post-COVID-19)

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Volume 12: Global Health, Infectious Surveillance, and Public Health Detection

Part I: Disease Surveillance Systems

• Global Influenza Surveillance and Response System (GISRS)
• WHO Integrated Disease Surveillance (IDS)
• CDC’s BioSense and National Syndromic Surveillance Program
• Genomic surveillance for SARS-CoV-2 variants (GISAID, Nextstrain)
• Wastewater-based epidemiology

Part II: Neglected Tropical Diseases (NTDs)

• Diagnostics for dengue, chikungunya, Zika (NS1 antigen, IgM, PCR)
• Point-of-care tests for malaria (RDTs), leishmaniasis (rk39), Chagas
• Rapid tests for schistosomiasis, lymphatic filariasis, onchocerciasis

Part III: Tuberculosis Detection

• Sputum smear microscopy (Ziehl-Neelsen, fluorescence)
• Xpert MTB/RIF Ultra and Xpert XDR (Cepheid)
• Line probe assays (Hain, GenoType)
• Interferon-gamma release assays (IGRAs) vs. tuberculin skin test
• Lipoarabinomannan (LAM) urine test for HIV-associated TB

Part IV: HIV and Sexually Transmitted Infections

• Fourth/fifth generation HIV tests (Ag/Ab combo)
• HIV viral load and drug resistance genotyping
• Rapid syphilis tests (Treponemal/non-treponemal)
• NAAT for chlamydia, gonorrhea, trichomonas, mycoplasma
• HPV self-sampling kits

Part V: Maternal and Child Health Detection

• Point-of-care early infant HIV diagnosis
• Group B streptococcus screening
• Congenital infection panels (CMV, toxoplasmosis, rubella, Zika)

Part VI: Bioterrorism and Emerging Threats (2020–2026)

• Detection of anthrax (Bacillus anthracis), plague (Yersinia pestis), tularemia
• Multiplex PCR for biothreat agents
• Field-deployable sequencing (MinION) for outbreak response
• Pandemic preparedness diagnostics (Project NextGen, BARDA)

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Appendixes (across all volumes)

1. Glossary of diagnostic terms
2. Normal laboratory reference ranges (age/sex-specific)
3. Diagnostic algorithm flowcharts (chest pain, jaundice, anemia, etc.)
4. Timeline of major diagnostic innovations (prehistory–2026)
5. FDA/CE-approved molecular and imaging diagnostics (2020–2026)
6. List of rare disease diagnostic consortia (Undiagnosed Diseases Network, Solve-RD)
7. ICD-11 codes for diagnostic findings
8. LOINC and SNOMED CT coding guide for lab tests
9. Biosafety levels for infectious disease testing
10. Index (cross-referenced by disease, test, technology, and volume)

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