Why lab tests are important

Why lab tests are important

Let us come together to dispel harmful myths.

One of the greatest advances of the 21st century is none other than the Internet.

Doctors are continually prompted to read more about their specialties so as to be in the know as new drugs, technologies and diagnostics come up, even when they are still years away from being available locally.

Patients now make better partners in their care as they get to embrace equal participation in decision-making.

The one part, though, that still has some way to go is patients’ understanding of diagnostics, which are a very critical component of treatment.

Laboratory and imaging tests are key in aiding diagnosis, monitoring treatment progress, monitoring toxicity, monitoring recovery and confirming cure.

With all these functions, it is imperative that patients begin to acknowledge the importance of diagnostics and have a basic understanding of the results.

For example, a full blood count (full haemogram) is a very common and quite basic test done in patients presenting to hospital with almost every complaint.

In layman’s terms, it basically says that the patient has bacteria in the bloodstream, but bacteria in the bloodstream is actually a life-threatening condition called septicaemia that is fairly rare and has an exceedingly high mortality rate.

This displays how, as practitioners, we have failed in helping our patients understand the relevance of the diagnostics we prescribe.

The only patients who seem to have some level of insight on the importance of these diagnostics are those with chronic conditions on long-term follow-up.

These include patients suffering from cancer who understand tumour markers, size of mass and white cell counts, HIV patients on antiretrovirals who fiercely protect their CD4 counts and monitor viral loads, and diabetics who care about their blood sugar levels.

For acute conditions like malaria, pneumonia, sore throats, colds and flu and urinary tract infections, tests serve three main functions.

First, they confirm diagnosis such as a malaria slide for microscopy to show the parasite or a chest X-ray to show lung consolidation in pneumonia.

The tests can also be used to reflect severity. In this case, a full blood count showing a very high level of white blood cell counts shows that the body is in overdrive to try and contain the infection, irrespective of where it is, and hence explaining the high fever; or a urine analysis that shows a high number of pus cells indicating a more severe infection.

Finally, repeating the same test at intervals helps to demonstrate that the body is responding to treatment, hence in malaria, if the density of the malaria parasite is decreasing with treatment, then it means the drug used is working.

In Kenya, we do not have a centralised patient record system. If a patient is seen at the same hospital or clinic, their care is documented in the file or online record.

Once the patient changes hospitals, the doctor is taken back to zero. The patient won’t come with a record showing what has been done so far and what the diagnostic findings have been so far.

Because of this, many tests are repeated unnecessarily and critical information is lost.

For this reason, it is important for patients to wisen up and always keep a copy of all lab reports and imaging records.

It helps to have a personal medical file at home where one stores all these results among other medical records such as discharge summaries from previous admissions, vaccination records and even copies of prescriptions given out over time.

This is the first step towards the patient getting more involved in their care.

It also helps to have your doctor explain each test being ordered, why it is being ordered and how it influences the decision-making process in your care.


Sometimes, tests may be ordered for documentation of your status at the first contact with your doctor.

These allow for future reference in case the situation changes.

This is common in instances such as HIV exposure (such as a needle prick) where one’s liver function tests and kidney function tests are taken in healthy individuals prior to starting a 28-day course of anti-retrovirals to prevent HIV.

Another set of important tests are those ordered in apparently healthy individuals for purposes of screening for medical conditions.

It is paramount that one understands that screening tests are not absolute. They are designed to be highly sensitive to picking out a potential problem.

A negative result is hence really good feedback. A positive result, on the other hand, is not a 100 per cent indication that one has the disease.

Further confirmatory tests are required to ascertain the presence of the condition. Confirmatory tests are mostly expensive and possibly invasive and hence are reserved for those with a positive screening test.

Some people fear going for screening tests especially in cases of cancer screening, because they don’t know the difference between the two aforementioned tests.

With our new-age access to medical information, patients should read up more on diagnostics and their role as they read on their conditions.

Let us come together to dispel harmful myths. For instance, cancer patients who have already been diagnosed with stage four cancer in Kenya with less sophisticated tools, spend so much money to travel to India for a Positron Emission Tomography Magnetic Resonance Imaging Scan, commonly known as the PET-MRI or the PET scan, without realising it is just a sophisticated imaging method and not a treatment option!