Septic Thrombophlebitis

Knowledge Check

Exam-style MCQs aligned with these notes. Available to Hyperexcision Scholar members.

Log in to access
Last updated: June 26, 2026Bookmark

Septic thrombophlebitis is characterised by a venous thrombus, inflammation of the vein, and pus formation. It can affect superficial or deep veins.

Staphylococcus aureus is the most common causative organism.

Septic thrombophlebitis is suspected when there is:

  1. Persistent fever > 72 hours despite appropriate antibiotics
  2. Patients with vascular catheter or other risk factors

Causes of septic thrombophlebitis

Category/VesselCausesNota bene
Catheter-relatedPeripheral IV cannulation, venipuncture, central venous catheter, PICC lines, and indwelling SVC/IVC cathetersThis is the most common cause
Internal jugular veins (Lemierre syndrome)Pharyngitis, peritonsillar abscess and dental infectionThe most common causative organism is Fusobacterium necrophorum
Pelvic veinsEndometritis, pelvic inflammatory disease, childbirth, septic abortion, and intra-abdominal infections
Dural venous sinusesMastoiditis, otitis media, sinusitis, and meningitis
Portal vein (Pylephlebitis)Appendicitis, diverticulitis, pancreatitis, inflammatory bowel disease, and other intra-abdominal infections
  • Causative organisms
    • Staphylococcus aureus
    • Streptococcus spp.
    • Anaerobes
    • Gram-negatives
    • Candida spp.
    • Polymicrobial
  • Common sites
    • Peripheral veins
    • Pelvic veins
    • Superior vena cava (SVC)
    • Internal jugular vein
    • Portal vein (pylephlebitis)
    • Dural venous sinuses
  • Risk factors
    • Neonates
    • Advanced age
    • Malignancy
    • Hypercoagulable states
    • Burns
    • Long-term steroids
    • Intravenous drugs use
    • Pregnancy or postpartum
    • Central venous catheters
  • Signs and symptoms
    • Fever
      • Spiking persistent postpartum fevers > 38 C for pelvic thrombophlebitis (”Enigmatic fever”)
    • Ill-appearing
    • Local pain
    • Tender vein
    • Erythema
    • Swelling
    • Purulent drainage from the catheter site
    • Abdominal pain for pylephlebitis
    • Abdominal pain radiating to the groin for pelvic thrombophlebitis
      • Deep septic pelvic thrombophlebitis may have minimal abdominal tenderness
  • Investigations
    • CT scan with contrast
      • Filling defect (thrombus)
      • Low density lumen
      • Sharp enhancement of the wall of the vein
      • Perivascular inflammation
    • MRI or MR venography for dural venous sinus thrombosis or when CT is unavailable
    • Ultrasound for peripheral thrombophlebitis
    • Cultures
      • Blood cultures
      • Catheter tip culture
      • Culture of purulent material
    • Other tests
      • CBC
      • Urea and creatinine
      • Electrolytes
      • LFTs
      • Coagulation panel
      • CSF is CNS involvement is suspected
  • Treatment
    • Remove the source
      • Remove the infected IV catheter
      • Drain abscesses if present
    • Intravenous antibiotics
      • Broad spectrum → culture-specific
    • Anticoagulation to prevent propagation of the thrombus
    • Surgery for frank purulence
      • Excision of infected peripheral veins
  • Complications
Reference Intervals ›
Biochemistry
ACTHP: <80 ng/L
ALTP: 5–35 U/L
AlbuminP: 35–50 g/L
AldosteroneP: 100–500 pmol/L
Alk. phosphataseP: 30–130 U/L
α-AmylaseP: 0–180 IU/dL
α-FetoproteinS: <10 kU/L
Angiotensin IIP: 5–35 pmol/L
ADHP: 0.9–4.6 pmol/L
ASTP: 5–35 U/L
BicarbonateP: 24–30 mmol/L
BilirubinP: 3–17 μmol/L
BNPP: <50 ng/L
CRPP: <10 mg/L
CalcitoninP: <0.1 mcg/L
Calcium (ionized)P: 1.0–1.25 mmol/L
Calcium (total)P: 2.12–2.60 mmol/L
ChlorideP: 95–105 mmol/L
CholesterolP: <5.0 mmol/L
VLDLP: 0.128–0.645 mmol/L
LDLP: <2.0 mmol/L
HDLP: 0.9–1.93 mmol/L
Cortisol AMP: 450–700 nmol/L
Cortisol MidnightP: 80–280 nmol/L
CK ♂P: 25–195 U/L
CK ♀P: 25–170 U/L
CreatinineP: 70–100 μmol/L
FerritinP: 12–200 mcg/L
FolateS: 2.1 mcg/L
FSHP: 2–8 U/L ♂; >25 menopause
GGT ♂P: 11–51 U/L
GGT ♀P: 7–33 U/L
Glucose (fasting)P: 3.5–5.5 mmol/L
Growth hormoneP: <20 mu/L
HbA1C (DCCT)B: 4–6%
HbA1C (IFCC)B: 20–42 mmol/mol
Iron ♂S: 14–31 μmol/L
Iron ♀S: 11–30 μmol/L
Lactate (venous)P: 0.6–2.4 mmol/L
Lactate (arterial)P: 0.6–1.8 mmol/L
LDHP: 70–250 U/L
LHP: 3–16 U/L
MagnesiumP: 0.75–1.05 mmol/L
OsmolalityP: 278–305 mosmol/kg
PTHP: 0.8–8.5 pmol/L
PotassiumP: 3.5–5.3 mmol/L
Prolactin ♂P: <450 U/L
Prolactin ♀P: <600 U/L
PSAP: 0–4 mcg/mL
Protein (total)P: 60–80 g/L
Red cell folateB: 0.36–1.44 μmol/L
Renin (erect)P: 2.8–4.5 pmol/mL/h
Renin (recumbent)P: 1.1–2.7 pmol/mL/h
SodiumP: 135–145 mmol/L
TBGP: 7–17 mg/L
TSHP: 0.5–4.2 mU/L
T4P: 70–140 nmol/L
Free T4P: 9–22 pmol/L
TIBCS: 54–75 μmol/L
TriglyceridesP: 0.50–2.3 mmol/L
T3P: 1.2–3.0 nmol/L
Troponin TP: <0.1 mcg/L
Urate ♂P: 210–480 μmol/L
Urate ♀P: 150–390 μmol/L
UreaP: 2.5–6.7 mmol/L
Vitamin B12S: 0.13–0.68 nmol/L
Vitamin DS: 50 nmol/L
Arterial Blood Gases
pH7.35–7.45
PaCO₂4.7–6.0 kPa
PaO₂>10.6 kPa
Base excess±2 mmol/L
Urine
Cortisol (free)<280 nmol/24h
Hydroxyindole acetic acid16–73 μmol/24h
Hydroxymethylmandelic acid16–48 μmol/24h
Metanephrines0.03–0.69 μmol/mmol cr.
Osmolality350–1000 mosmol/kg
17-Oxogenic steroids ♂28–30 μmol/24h
17-Oxogenic steroids ♀21–66 μmol/24h
17-Oxosteroids ♂17–76 μmol/24h
17-Oxosteroids ♀14–59 μmol/24h
Phosphate (inorganic)15–50 mmol/24h
Potassium14–120 mmol/24h
Protein<150 mg/24h
Protein/creatinine ratio<3 mg/mmol
Sodium100–250 mmol/24h
Haematology
WCC4.0–11.0 ×10⁹/L
RBC ♂4.5–6.5 ×10¹²/L
RBC ♀3.9–5.6 ×10¹²/L
Hb ♂130–180 g/L
Hb ♀115–160 g/L
PCV ♂0.4–0.54 L/L
PCV ♀0.37–0.47 L/L
MCV76–96 fL
MCH27–32 pg
MCHC300–360 g/L
RDW11.6–14.6%
Neutrophils2.0–7.5 ×10⁹/L (40–75%)
Lymphocytes1.0–4.5 ×10⁹/L (20–45%)
Eosinophils0.04–0.44 ×10⁹/L (1–6%)
Basophils0–0.10 ×10⁹/L (0–1%)
Monocytes0.2–0.8 ×10⁹/L (2–10%)
Platelets150–400 ×10⁹/L
Reticulocytes0.8–2.0% / 25–100 ×10⁹/L
Prothrombin time10–14 s
APTT35–45 s
Paediatric
Pulse Rate (bpm)
Neonate140–160
Infant <1yr120–140
1–5 years110–130
5–12 years80–120
>12 years70–100
Respiratory Rate (tachypnoea)
0–2 months≥60/min
2–12 months≥50/min
1–5 years≥40/min
>5 years≥30/min
Blood Pressure (mmHg)
Term65/45
1 year75/50
4 years85/60
8 years95/65
10 years100/70
Weight Formulas
3–12 months(a + 9)/2 kg
1–6 years2a + 8 kg
>6 years(7a − 5)/2 kg
Haemoglobin (g/dL)
Term newborn13–20
1 month11–18
2 months10–15
1–2 years10–13
>2 years11–14
MUAC (6 months–5 years)
Obese>17.5 cm
Normal13.5–17.4 cm
At risk12.5–13.4 cm
Moderate malnutrition11.5–12.4 cm
Severe malnutrition<11.5 cm
Developmental Milestones
Social smile1.5 months
Head control4 months
Sits unsupported7 months
Crawls10 months
Stands unsupported10–12 months
Walks12–13 months
Talks18 months
CSF WBC (/mm³)
Term newborn0–25
>2 weeks0–5
Calculator ›

Leave a Reply