Blood Culture Test Overview, Process, Post-care & More

A blood Culture Test detects the presence of bacteria (bacteraemia), viruses (viremia), or fungi (fungemia) in the bloodstream. A human body can become infested with microorganisms like bacteria and viruses. If the pathogens in the bloodstream are not detected early, serious complications can occur. A regular blood test can also identify the presence of a virus in the bloodstream. However, a routine blood test will fail to detect the presence of fungi and bacteria in the bloodstream. After a culture blood test, the samples are grown/incubated in the lab. A routine blood test cannot grow microbes in lab conditions, thus failing to detect their presence in the bloodstream.

Usually, a blood infection occurs from a specific site/organ in the body. For example, some people might suffer from UTI (Urinary Tract Infection). A urinary tract infection can originate from the bladder or the kidneys and spread into the bloodstream. A blood culture test is the only way to detect the infection spread from the kidneys or the bladder into the bloodstream. Sometimes, blood infections can get serious, known as septicemia. The human body’s response to a severe blood infection is known as sepsis. Before the blood infection becomes life-threatening, it is better to take a blood culture test. Now that you understand the meaning of a blood culture test let us know its procedure and aftercare.

The Procedure of the Blood Culture Test

The procedure for a culture blood test starts with sample collection. Usually, two blood samples are collected from the patient’s veins. Blood samples are gathered from different veins of the patient to detect microbes easily. By collecting multiple samples, lab technicians increase the likelihood of finding microbes in the bloodstream. With the help of multiple samples, lab technicians can differentiate between true pathogens. Sometimes, a phlebotomist might need to collect more than two samples for a blood culture test. It’s because true pathogens might be present in more than one blood culture in the body. Sometimes microbes are present in small quantities, and it may take many days to grow them in lab conditions. For the same reason, a blood culture test might take many days to produce a detailed report.

After the phlebotomist collects the samples, it is placed in different culture bottles. These culture bottles are infused with broth, a liquid medium that helps microbes to grow. The liquid medium is infused with nutrients to augment the growth of microbes. For children, a phlebotomist can collect only a single sample for a culture test. When children and infants suffer from a blood infection, it spreads throughout the bloodstream quickly. When the infection spreads throughout the bloodstream, it is easier to detect microbes with a culture test. Also, the blood sample for a blood culture test is larger for adults and smaller for children.

After placing the blood samples in culture bottles, lab technicians wait for the microbes to grow. The bacteria or fungi must grow in sufficient numbers to be recognised by the machine. Blood culture readings are produced by a diagnostics machine. Once the bacteria or fungi grow in adequate numbers, the readings are developed in a couple of days. When microbes are present in small quantities, they might take several days to mature. Also, some microbes can be hard to detect, and a blood culture test might take several days.

Results After a Blood Culture Test

Blood culture test results will tell you the exact name of microbe(s) present in the bloodstream. It will also tell whether the blood infection is in the initial phase or not. One will get to know the presence of microbes in large quantities via a blood culture test. Rapid blood culture tests are also offered by labs for specific microbes. Microbes like MRSA and E. coli can be detected quickly with a rapid blood culture test. The patient will receive a detailed report after a culture test. Positive blood culture in the report indicates the presence of microbes in the bloodstream. A negative blood culture means the patient isn’t suffering from a blood infection.

Aftercare for a Blood Culture Test

A blood sample for a blood culture test is collected from the vein puncture of the patient. A needle is inserted in vein puncture to collect a blood sample for a culture test. After the sample is collected, the puncture site can become red and swollen. In some cases, the area around the puncture site can become hot after drawing blood. The patient might also develop pain around the puncture site after sample collection. In any such scenario, the patients should get in touch with the nursing staff. The nursing staff might apply some Epsom salt to reduce the redness and swelling around the vein puncture site.

When to Get a Blood Culture Test?

A practitioner may suggest a blood culture test due to symptoms related to blood infection. Symptoms of sepsis indicate the presence of bacteria, viruses, and fungi in the human body. If you have the following sepsis symptoms, you need a blood culture test right away:

• Fever
• Chills
• Fast breathing
• Increased heartbeat
• Less than average urination

As the blood infection becomes severe, the patient might experience inflammation in the body. Sudden drops in blood pressure might occur due to serious blood infections. One or more organs can fail due to increased blood infection. Therefore, it is better to opt for a blood culture test before the infection becomes life-threatening.

Cost of a Blood Culture Test

In India, the average culture blood test price is INR 650. In some cities, the cost of a blood culture test can go up to INR 1,200. It is crucial to note that the average price for a blood culture test is for lab tests. You will have to pay around INR 600 for taking the blood culture test in a lab/diagnostic centre. Some people also choose the home sample collection facility for a blood culture test. Costs increase on home sample collection for a blood culture test. Get tested for the presence of microbes in the body now!