Laboratory Samples: Complete Guide to Specimen Types, Anticoagulants & Preservatives
Master list of 120+ clinical specimens • Blood • Urine • CSF • Swabs • Tissues • Molecular • Anticoagulants & transport media
🩸 Core Blood Samples
15+ subtypes
- Whole Blood (venous/capillary/healstick)
- Serum (clot activator/SST)
- Plasma: EDTA, Heparin-Li, Citrate, Fluoride
- Buffy coat, PRP, PPP, Dried Blood Spot
- Arterial / Cord blood
🧪 Urine & Stool
20+ methods
- Random / First morning / Midstream clean-catch
- 24h, 12h, timed urines (4-72h)
- Catheter / Suprapubic / Pediatric bag
- Stool: random, 24h/72h quantitative, O&P
- FIT, C.diff, Calprotectin, rectal swab
🧠 CSF & Neurological
- CSF tube 1 (Chemistry)
- CSF tube 2 (Microbiology)
- CSF tube 3 (Cell count)
- CSF tube 4 (Molecular/PCR)
- Ventricular / Cisternal fluid
🌬️ Respiratory Samples
- Sputum spontaneous/induced, Tracheal aspirate
- BAL, ETT aspirate, Pleural fluid
- NP/Throat/Nasal swab, Nasal wash
- Lung biopsy, EBC, AFB series (3x morning)
🔬 Comprehensive Specimen Classification
🩸 Whole Blood & Derivatives
- EDTA (Lavender) – CBC, HbA1c, Flow cytometry
- Sodium Citrate (Lt Blue) – Coagulation (PT/APTT)
- Heparin (Green) – Chem, STAT electrolytes
- Fluoride/Oxalate (Gray) – Glucose, Lactate
- ACD/CPD/CPDA-1 – Blood bank, storage
- Dried Blood Spot (Guthrie) – Newborn screening
🧴 Serum & Plasma specifics
- Serum separator (SST) – Chem, hormones, serology
- Lithium heparin plasma – Cardiac markers
- Citrated plasma – D-dimer, platelet function
- Fluoride plasma – Glucose tolerance tests
- Capillary fingerstick – POC glucose, neonatal screen
🧫 Gastrointestinal, Genitourinary & Synovial Specimens
Gastric & Abdominal
- Gastric aspirate, Duodenal fluid
- Peritoneal/ascitic fluid (paracentesis)
- Pancreatic juice (ERCP), Bile fluid
- Peritoneal dialysate, Esophageal brushing
Reproductive & Semen
- Semen analysis, Post-vasectomy
- Prostatic massage fluid
- Urethral/endocervical/vaginal swabs
- Amniotic fluid, CVS, Breast milk
Musculoskeletal & Synovial
- Synovial fluid (knee/hip/shoulder)
- Bone marrow aspirate (EDTA/heparin)
- Bone marrow core biopsy (formalin)
- Joint aspirate for crystal analysis
Ocular (Eye) Samples
- Corneal scraping (keratitis culture)
- Conjunctival swab, Vitreous humor
- Aqueous humor tap, Lacrimal fluid
- Contact lens case solution
🦷 Skin, Hair, Nail & Advanced Swab Panels
🧴 Dermatology
- Skin scraping (KOH – fungal)
- Punch biopsy (histopathology)
- Hair pluck (heavy metals / culture)
- Nail clipping (onychomycosis)
- Sweat chloride (CF – pilocarpine)
- Blister fluid aspirate
🩹 Microbiology Swabs & Transport
- Wound / abscess / burn swab
- Bed sore / surgical site / umbilical
- Rectal for VRE/CRE & STI (LGV, Mgen)
- Genital ulcer, Ear swab, Eye swab
- Media: Amies, Stuart, Cary-Blair, VTM/UTM
🔬 Histopathology & Cytology (10+ sample types)
- Surgical resection (tumor, margins)
- Core needle biopsy (liver, kidney, prostate)
- Fine Needle Aspirate (thyroid, breast, LN)
- Endoscopic biopsies (stomach, colon)
- Cervical smear (Pap, Liquid-based cytology)
- Pleural/peritoneal fluid cytology
- Urine cytology (bladder CA)
- Sputum cytology (lung CA)
- Fixatives: 10% NBF, alcohol, CytoLyt
⚖️ Forensic & Postmortem Samples
- Postmortem cardiac/femoral blood
- Vitreous humor (electrolytes, alcohol)
- Postmortem urine, gastric contents
- Liver tissue, hair segmental, bone (DNA/heavy metals)
🧬 Specialized, Veterinary & Emerging Samples
Saliva & Oral
- Whole/stimulated saliva – hormones, drugs
- Buccal swab (DNA, pharmacogenetics)
- Oral rinse, Meconium (neonatal drugs)
- Sweat patch (continuous drug monitoring)
Environmental & Veterinary
- Water (drinking/wastewater), Soil cultures
- Air sampling (settle plate, impinger)
- Food pathogen testing (meat, dairy)
- Animal blood / tissue (necropsy)
Molecular & Emerging
- DBS for PCR, RNA stabilization (RNAlater)
- Seminal fluid (forensic PSA/DNA)
- Tympanic fluid, CSF molecular panel
- Liquid biopsy (ctDNA from plasma)
🧪 Anticoagulants & Preservatives – Quick Reference
💉 Anticoagulants by tube color
- Lavender (EDTA) – Hematology, CBC, HbA1c
- Light Blue (Na Citrate) – Coagulation studies
- Green (Heparin Li/Na) – Chem, ammonia
- Gray (NaF/KOx) – Glucose, lactate
- Yellow (ACD/SPS) – HLA, Blood culture
- CPD/CPDA-1 – Blood bank storage
🧴 Preservatives & fixatives
- 10% NBF – Histopathology (gold standard)
- Glutaraldehyde – Electron microscopy
- RNAlater – RNA preservation (tissue/DNA)
- Boric acid – Urine culture preservation
- Thymol/Toluene – Urine chemistry
- SAF / PVA / Formalin – Stool O&P, parasites
- Cary-Blair / Amies – Stool & swab transport
📦 Transport Media
VTM (viral), UTM, Stuart, Amies, Cary-Blair, Sputum transport medium
VTM (viral), UTM, Stuart, Amies, Cary-Blair, Sputum transport medium
⚠️ Rejection criteria
Hemolyzed, clotted, mislabeled, insufficient volume, wrong container, improper transport temperature.
Hemolyzed, clotted, mislabeled, insufficient volume, wrong container, improper transport temperature.
📋 Master Specimen Index: 120+ Types (Clinical Reference)
Part 1-3: Blood, Urine, Stool
- 15 blood derivatives: venous/capillary/serum/plasma/PRP/DBS
- 12 urine: random, 24h, catheter, suprapubic, pediatric bag
- 8 stool: O&P, FIT, calprotectin, C.diff, 72h fat
Part 4-6: CSF, Resp, GI
- CSF 4-tube protocol, ventricular fluid
- BAL, NP swab, sputum AFB, pleural fluid
- Gastric, peritoneal, ascites, bile, duodenal
Part 7-9: GU, Synovial, Ocular
- Semen, cervical swabs, amniotic fluid
- Synovial (knee, hip), bone marrow aspirate/biopsy
- Corneal scrapings, vitreous/aqueous humor
Part 10-13: Skin, Swabs, Histo, Forensic
- Skin/hair/nail, sweat chloride
- Wound/rectal/ear/genital swabs, transport media
- FNA, Pap, surgical tissue, postmortem vitreous
📌 Sample Collection & Handling – Quality corner
✓ Proper identification: Two patient identifiers
✓ Order of draw: Blood culture → citrate → serum → heparin → EDTA → fluoride
✓ Fasting requirements: Glucose, lipids, gastrin
✓ Timed samples: 24h urine preservation with boric acid/refrigeration
✓ Order of draw: Blood culture → citrate → serum → heparin → EDTA → fluoride
✓ Fasting requirements: Glucose, lipids, gastrin
✓ Timed samples: 24h urine preservation with boric acid/refrigeration
⚠️ Common rejection reasons:
- Hemolyzed specimens (potassium, LDH)
- Clotted EDTA/Citrate samples
- Insufficient volume (pediatric microtainers)
- Mismatched labels / missing requisition
❓ Frequently Asked Questions (Specimen Integrity)
📌 What is the most common anticoagulant for CBC? ▼
🧫 Which preservative is used for stool Ova & Parasite? ▼
🩸 Why is Sodium Fluoride used for glucose testing? ▼
🧬 Best tube for molecular / PCR testing? ▼
