Blood cultures
Blood culture tests are used to test for the presence of bacteria and yeast in the blood. Some forms of yeast and many different forms of bacteria (as well as viruses and fungi) are responsible for causing illness and infection.
Why is the test used?
The blood culture test is used to identify bacteria and yeast in the bloodstream; this is usually done to identify the source of an illness or infection and to help doctors to diagnose systemic infections (when the infection cannot be controlled at the site, the bacteria leak into the blood supply and this may cause other organs and parts of the body to become infected).
The test will usually be ordered when the patient shows signs or symptoms of sepsis (this is an inflammatory condition, which is caused by the body’s response to a systemic infection); symptoms include fatigue, chills, fever and a higher white blood count than usual.
How is the test performed?
The test is done by using a sample of blood taken from a vein in the arm; two samples will be taken and placed in different vials. The vials will contain nutrients that allow the bacteria or yeast to thrive; one will be oxygen-rich and the other will be anaerobic (without oxygen). The tests are usually carried out at intervals during a set period of time; this allows doctors to see microorganisms which are released into the bloodstream gradually and intermittently. Most laboratories monitor samples over a period of time.
The blood samples are usually collected from different veins in the arm.
What do the test results show?
If the test result comes back positive, this usually means the individual has an infection, which has been caused by a bacterium or a form of yeast. Sepsis is a serious, potentially life-threatening disease and will be treated very quickly in the event of a positive result.
If the tests come back negative, it is unlikely that the patient has sepsis; however, it may still be possible and if symptoms persist, the doctor may order further tests. The blood culture test may be carried out in addition to full blood count or urine, CSF (cerebrospinal fluid: this is the fluid which surrounds the spinal cord and the brain) or sputum tests.
Specific Blood Tests
- Specific Blood Tests
- Factor V Leiden Mutation and PT 20210 Mutation
- Ferritin Test
- Fibrinogen
- Fructosamine
- FSH Test
- G6PD
- Gastrin
- GGT
- Glucose test
- Growth hormone
- Haemoglobin
- Haptoglobin
- HbA1c test
- HDL Cholesterol Test
- Helicobacter Pylori test
- Heparin Anti-Xa
- Hepatitis A Virus
- Hepatitis B Virus
- Hepatitis C Virus
- Her-2/neu Testing
- Heterophil Antibody Titre
- High-Sensitivity C-Reactive Protein
- HIV Antibody Test
- HIV Resistance Testing
- HIV Viral Load
- IGF-1
- Immunoreactive Trypsin
- Insulin
- Iron test
- LDH
- LDL Cholesterol Test
- Lead Test
- LH Test
- Lipase Test
- Lipoprotein (a)
- Lithium
- Lupus Anticoagulant
- Lyme disease test
- Maternal screening
- Mercury, Urine and Blood
- Mycophenolic Acid
- Myoglobin Test
- Oestrogen
- Osmolality
- Overdose Drug Test
- Paracetamol
- Parathyroid Hormone
- Parvovirus B19
- PCV
- Pertussis
- Phenobarbital
- Phenytoin
- Phospate
- Platelet Count
- Porphyrins
- Potassium Test
- Prealbumin Test
- Procalcitonin
- Progesterone Test
- Prolactin
- Prostate-Specific Antigen
- Protein 24 Capsid Antigen
- Protein C and Protein S
- Protein Electrophoresis Immunofixation Electrophoresis
- Prothrombin Time
- PSEN1 Test
- PTH
- Reticulocyte count
- Rheumatoid factor
- Rubella test
- Salicylic Acid
- Serotonin
- Sex Hormone Binding Globulin
- Sickle Cell Test
- Sirolimus
- Smooth Muscle Antibody
- Sodium Test
- Soluble Mesothelin-Related Peptides
- Synacthen Test
- Syphilis Test
- Tacrolimus
- Tau protein
- Testosterone Test
- Theophylline & Caffeine
- Thiopurine s-methyltransferase
- Thyroglobulin (Tg)
- Thyroid peroxidase antibody (TPOAb)
- Thyroid-Stimulating Hormone
- Thyroxine
- TIBC, UIBC & Transferring
- TORCH Test
- Total Protein test
- Triiodothyronine
- Triglycerides Test
- Troponin test
- Urea test
- Uric Acid
- Valproic Acid
- Vancomycin
- Very Low Density Lipoprotein
- Vitamin B12 and Folate
- Vitamin D
- West Nile Virus
- White blood cell differential count
- Zinc Protoporphyrin
- Activated Clotting Time
- ACTH
- Albumin
- Aldosterone and Renin
- Alkaline Phosphatase Test
- Allergen-Specific IgE Antibody Test
- Alpha-1 Antitrypsin
- Alpha-Fetoprotein
- ALT
- AMA
- Ammonia
- Amylase Test
- Angiotensin Converting Enzyme
- Antinuclear Antibody
- Antithrombin
- Apolipoprotein A-I
- Apolipoprotein E Genotyping
- aPTT
- AST
- Bicarbonate
- Bilirubin
- Blood cultures
- Blood film
- Blood Gas Tests
- Blood Ketones
- Brain Natriuretic Peptide
- BRCA-1 & BRCA-2
- CA 125
- Cancer Antigen 15-3
- Cancer Antigen 19-9
- C-peptide
- Caeruloplasmin
- Calcitonin
- Calcium Test
- Carbamazepine
- Cardiac Risk Assessment
- Cardiolipin Antobodies
- Catecholamines, Plasma and Urine
- CCP
- CD4 and CD8
- CEA Test
- CF Gene Mutation Testing
- Chickenpox and Shingles Tests
- Chloride Test
- Cholesterol Test
- Chlorinesterase Test
- Chromogranin A
- Ciclosporin
- CMV
- Coagulation Factors
- Coeliac Disease Tests
- Copper
- Cortisol Test
- Creatine Kinase CK-MB Test
- Creatine Kinase Test
- Creatinine
- Creatinine Clearance
- C-Reactive Protein
- Cystatin C
- D-Dimer
- DHEAS
- Digoxin
- Direct LDL cholesterol
- eGFR - Calc. Creatinine Clearance
- Electrolytes
- Epstein-Barr Virus Antibodies
- Erythrocyte Sedimentation Rate
- Erythropoietin
- Ethanol
Blood Test Guide
- Blood Tests
- Types of blood tests
- what to expect
- What are the risks of blood tests?
- What do blood tests show?
- Specific Blood Tests