On the first day I chanced upon your Black African Ghanaian Beauty I instantly became dumbfounded and mesmerized as though I had been enchanted by a magical spell and as though I had seen an angel brought down from heaven to live amongst men. That experience instantly reminded me of the story of Paul and Barnabas who were seen by the people of Lystra as the gods Hermes and Zeus who had come in the form of humans to visit them after they (Paul and Barnabas) healed a crippled man as recorded in Acts of the Apostles 14:8-18.
Before I met you my love, I have enjoyed till date a very blissful relationship with another very beautiful lady called MEDICAL LABORATORY SCIENCE. Prior to initiating our love relationship, some “background checks” I made led me to some very interesting discoveries. We have kept faith believing that conditions will get better someday in spite of her very challenging past & present “living conditions”.
Medical laboratory science in Ghana at its birth till a certain stage in our history had no school to train its practitioners in the theory and science behind the routine tests performed in hospital laboratories. People with absolutely no form of formal education could be trained on the bench as bench trained medical laboratory professionals.
Practical skills they learnt and practised included:
- Blood sample taking (phlebotomy).
- Preparing blood films (thick and thin blood films) on glass slides.
- Taking bone marrow aspirates.
- Various staining techniques such as the Ziehl-Neelsen, Auramine-phenol, gram stain, Giemsa, etc. that “paint, color or expose” disease causative organisms
- How these stains (dyes) employed in these staining techniques were prepared.
- The quantity of water to be added a certain weight of salt to make it suitable for the laboratory purposes.
- How much water needed to be added to a particular strength or concentration of alcohol for effective antisepsis and use in the laboratory.
With current advancements and automation in the field of medical laboratory science and disease diagnosis & with the advent of Point of Care Testing (POCT) used at wards and clinics and Rapid Diagnostic Test kits (RDT); many people today may not appreciate the very humble beginnings of the profession.
- Hand-operated-centrifuges requiring excessive utilization of physical strength and manpower were used for spinning samples.
- Counting the different types of White Blood Cells (WBCs) in a special type of glass slide called a “counting chamber” with the aid of a microscope. The counting chamber is still used in some parts Ghana and the world though.
- “Blood plasma” (the part of blood made of water) was mixed with various chemicals prepared in our labs for the measurement of analytes such as “blood sugar”, levels of “cholesterol”, “hormones”, “enzymes” and other products resulting from the body’s biological-and-chemical reactions in the body’s states of health and disease.
- Laboratory professionals were solely in charge of taking bone marrow aspirates.
- Frogs or toads were used for conducting tests for pregnancy.
- Human urine was tasted on the tongue’s taste buds.
The practices at the time were very laborious, time consuming whilst (5&6) were very weird and deemed unimaginable in modern day – but these form a part of our history.
Today, people are able to access Rapid Diagnostic Test kits (RDTs) for malaria from pharmacy shops, etc. for malaria self-testing, etc. THAT NOTWITHSTANDING, THE ROLE OF THE MEDICAL LABORATORY SCIENTIST IS INDISPENSABLE. Without performing quality control checks on these RDTs, how can the accuracy of the test result (whether positive or negative) be vouched for? How could false positive & false negative test results be detected?
FALSE NEGATIVE RDT RESULTS could be seen in:
- Cases of low parasitemia (low malaria or plasmodium parasite count).
- “PROZONE EFFECT” – where there are too many plasmodium parasite components competing to be detected by the RDT.
- Non plasmodium falciparum malaria infections – many malaria RDT manufacturers produce those capable of detecting only malaria infections resulting from Plasmodium falciparum as that is the most dominant species and cause of malaria in our subregion. This test kit will be unable to detect malaria caused by Plasmodium malariae, P. ovale, P. vivax and P. knowlesi.
Scientific research has proven that the component of the plasmodium parasite [called the HRP-2 (Histidine Rich Protein 2) detectable by the test kit] is still present in blood circulation for at least a month to two after recuperating from malaria. This is a cause of FALSE POSITIVE RDT RESULTS.
MALARIA MICROSCOPY (not RDT) REMAINS THE GOLD STANDARD FOR THE DETECTION AND DIAGNOSIS OF MALARIA, carried out in our hematology laboratories.
Not only are plasmodium parasites seeable in malaria microscopy but the identification of the exact causative species can be made, be it: P. falciparum, P. malariae, P. ovale, P. vivax or P knowlesi.
Identification of the exact causative species enables treatment with the exact tailor-made drug-combinations most effective against that particular species. Species identification in malaria infection is very important as infections from P. ovale and P. vivax will require an additional treatment regimen with primaquine else would result in a relapse if undetected and not treated. I usually recommend that patients avoid self-medication but visit a health facility where there exists a full complement of health professionals including but not limited to medical laboratory professionals, pharmacists, nurses, etc for comprehensive healthcare.
I believe you might have noticed a drift from the “+, ++, +++ system of malaria results reporting” to a “system of counting the number of plasmodium parasites”. This new system of malaria result reporting has proven clear superiority over the previous system and is an excellent tool for monitoring: the treatment of the disease condition & the efficacy of drugs used.
Readily accessible First Response RDT kits for HIV are used by many for HIV diagnosis without the performance of a second independent test. The performance of a second, different & separate independent test will classify patient’s “HIV status” as either: reactive, non-reactive or indeterminate. Testing protocols in some health facilities employs the performance of an additional third separate independent test – thus for instance the utilization of HIV first response, OraQuick & SD Bioline test kits for HIV diagnosis.
Readily accessible TPHA or TPPA test strips are also used by many for diagnosing syphilis without the performance of VDRL (or RPR) for differentiating past treated syphilis infections from present infections.
It will be recalled that a false alarm was once raised about a patient on admission in a health facility issued with blood infected with syphilis for transfusion. This incidence caused some stir in the public domain and was reported by graphic online publications: of 1st December 2018 (KATH ‘contaminated blood’ claim: Investigations underway) & of 2nd December 2018 (KATH ‘contaminated blood’ test negative to HIV, Syphilis).
There have been several “unreported instances” when patients have been administered insulin shots after glucometers have produced outrageously high blood glucose readings at wards & clinics without ascertaining whether: these results are measured in mmol/L or mg/dL; the instrument (glucometer) is working optimally or not; etc.
These are some examples of wrong utilization of RDTs & POCT (Point of Care Testing). I do not seek to downplay its relevance but establish a very important fact that “these tools” (RDT & POCT) could be likened to a very dangerous weapon “when found in wrong hands”. Emphatically, the advent of technology birthing these tools cannot dispense the central role played by medical laboratory scientists in disease diagnosis.
Due to technological advancements and automation in medical laboratory science, it is sometimes not uncommon to find physicians and sometimes patients and their relatives (sometimes incited by physicians) lamenting about: delays in retrieving laboratory reports; questioning as captured in their own words “why a simple task like pushing machine buttons to generate laboratory reports take so long?”
Respectfully, an illiterate could be taught “how to push buttons on our analytical devices or machines to produce laboratory results or reports”. As a matter of fact, ordinary water instead of human samples like blood, plasma, serum, cerebrospinal fluid, urine could be administered to the analytical devices to produce laboratory reports.
ANYONE (aside a qualified medical laboratory professional) can “push buttons on our machines to generate results”, but: will these results necessarily make medical & scientific sense especially in relation to patients’ clinical condition? Can the accuracy & reliability of these results be vouched for? What mechanisms will be instituted for the detection of errors to guarantee quality?
In many versions of our hematological devices, nucleated Red Blood Cells (RBCs) are counted as White Blood Cells (WBCs) producing a falsely elevated WBC count & falsely reduced RBC count in patients suffering from severe anemia, the medical laboratory scientist goes ahead to do a blood film comment to perform a “corrected reticulocyte cell count & corrected WBC count” to correct this machine limitation. Samples which are lipemic & jaundiced affects the measurement of some parameters such as the hemoglobin levels. Some medications taken by patients can also affect the measurement of some parameters by the analytical machines. Gene xpert machines cannot detect Mycobacterium tuberculosis in bloody samples as that will cause blockages in machine components – a different method like either the auramine-phenol or Ziehl-Neelsen staining techniques would then have to be employed for the detection of Mycobacterium tuberculosis. The invention of these highly advanced & sophisticated technological laboratory devices has lessened the extremely laborious, very tiring, manual & time-consuming nature of work involved in the performance of many medical laboratory investigations. The work of the analytical machine is however not foolproof and the need of trained medical laboratory professionals still remains irreplaceable to supervise the operation of these advanced & sophisticated laboratory devices as these devices are obviously faster but not smarter. It is not every result that is printed and issued out because it has been generated by an analytical device (or machine) – a great deal of work goes into determining what results are issued out & which ones are not.
Quality control reagents (chemicals) are employed by medical laboratory professionals to perform quality control checks. These chemicals may consist of a combination of either:
- Chemicals for “normal & abnormal laboratory values”
- Chemicals for “normal, low and high laboratory values”
Measurements of these quality control chemicals is carried out daily at the that start of each shift (morning, afternoon & night shifts) to establish the stability of our analytical machines in generating accurate, reliable and timely laboratory reports.
Mathematical calculations such as the mean, standard deviation, coefficient of variation is done using values obtained from measurements of our quality control chemicals; graphs are drawn using answers derived from our mathematical calculations; on the basis of this and other mathematical & statistical techniques, a range of laboratory values considered acceptable and unacceptable is set to enable the laboratory scientist DETECT ERRORS. These errors may be either: ERRORS OF INACCURATE LABORATORY RESULTS or ERRORS OF IMPRECISE LABORATORY RESULTS. The medical laboratory scientist sometimes also “plays the role of a biomedical engineer” TROUBLESHOOTING & DIAGNOSING MACHINE MALFUNCTION in order to effect corrective remedies else work comes to an abrupt end. These operations are performed DAILY & PERIODICALLY. I dare say that, as simple as “pushing our machine buttons” may look or seem the lab physicians of the GMA & GCPS cannot quality control & troubleshoot our analytical devices.
PLEASE WATCH OUT FOR PART 2
Medical Laboratory Professional
Member, GAMLS National Communications Team