Overview: Electron Microscopy TEM Panel
Introduction: The Electron Microscopy TEM Panel is a diagnostic tool designed for ultrastructural tissue analysis using FFPE tissue samples. In India, transmission electron microscopy (TEM) is crucial for diagnosing glomerular diseases (minimal change, membranous nephropathy), storage disorders, neuromuscular conditions, and rare tumors, where light microscopy is inconclusive. High burden from underutilization in rural/low-SES patients, very limited TEM facilities (mostly in metros), delayed precise diagnosis leading to inappropriate therapy or progression. Per histopathology practices aligned with ICMR and Indian Society of Pathology guidelines, the test employs TEM for ultrastructural analysis over 1-2 days (after preparation) with high resolution, valuable for identifying podocyte changes, deposits, or inclusions. This diagnostic falls under tissue analysis and targets patients with unexplained renal/neuromuscular pathology after initial biopsy, addressing accurate detection to guide targeted treatment or prognosis. With elevated morbidity due to under-access, the test supports public health efforts by enabling precise ultrastructural diagnosis in referral centers. Its FFPE-based approach ensures reliable retrospective analysis.
Other Names: TEM Pnl.
FDA Status: FDA approved, CLIA certified for histopathology, compliant with 2025 standards.
Historical Milestone: TEM in renal pathology; in India, limited to major institutes.
Purpose: The test assesses 3 parameters including ultrastructural analysis to guide tissue evaluation, detect subcellular abnormalities, provide diagnostic report.
Test Parameters: 1. Ultrastructural Analysis, 2. Cellular Morphology, 3. Diagnostic Report.
Pretest Condition: No fasting required; patients should have prior biopsy with unexplained findings.
Specimen: FFPE tissue block (0.5-2 cm³), transported within specified times to maintain sample viability.Sample Stability: Indefinite when properly stored (paraffin-embedded blocks stable long-term).
Medical History: Patients should provide details on biopsy indication, light microscopy findings, clinical suspicion.
Consent: Written informed consent is required, detailing the test's purpose, potential risks of undiagnosed ultrastructural disease including progression, benefits of detailed analysis, and minimal discomfort (tissue already collected).
Procedural Considerations: The test involves sample processing using TEM by trained personnel to ensure sterile technique, prepare ultrathin sections, avoid artifacts, and interpret results within 1-2 days using provided controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols.
Factors Affecting Result Accuracy: Poor fixation, low tissue quality, or delays can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.
Clinical Significance: Abnormal ultrastructure indicates specific pathology, necessitating specialist input. Normal may require follow-up if suspicion high.
Specialist Consultation: Renal pathologists or neurologists should be consulted for interpretation.
Additional Supporting Tests: Immunofluorescence, light microscopy for confirmation.
Test Limitations: Requires expert interpretation; comprehensive approach required.
References: Indian Journal of Pathology 2024, TEM Studies India 2023.
