Concise Book of Medical Laboratory Technology Methods & Interpretations

Book Preface

The definition of health includes a state of complete and perfect physical, mental, social and spiritual well-being and not just the absence of disease or infirmity and good health is a fundamental right of every living human being on earth. However, modern world, though, has to an extent eliminated infectious diseases. But the focus has now shifted to lifestyle diseases. Pollution of every nature too has taken its toll. About half a century back, the predominant diseases used to be infective ones but now you may find individuals in mid-twenties waiting for their turn for open heart surgeries. Also, modern medicine has increased the longevity of life accompanied by attendant geriatric diseases like Alzheimer’s disease and malignancies. The polluted and toxic world has not spared the fetuses in utero and neonates. A new face of disease has emerged, diseases like HIV-AIDS and severe acute respiratory syndrome (SARS), are new entrants in the long list of infective diseases. We may have eradicated smallpox but tuberculosis and malaria have raised their heads with a vengeance. So, do what you might. Some forms of disease, mild or severe will strike every human being living. On getting sick, the patient first comes in contact with a clinician—medical or surgical. The clinician gives a patient hearing (if the patient is conscious) to his problems and symptoms and also takes note of various signs, which he sees or elicits. Sometimes, he may immediately arrive at a diagnosis and may under emergency circumstances institute treatment at first instances. In most cases, however, he will have a differential diagnosis in mind and to arrive at a specific diagnosis he usually orders for a battery of tests.

Various means of diagnosis are available.

1. Most important: Clinical laboratory tests which include any tissue or fluid obtained from the body.
2. Imaging sciences: X-rays, ultrasound, color Doppler, computerized axial tomography (CAT) scan, magnetic resonance imaging (MRI) scan and the latest positron emission tomography (PET) scan.
3. Electrical signal processing techniques: ECG, EMG, EEG and nerve transmission techniques, etc.
4. Direct visualization techniques: With the availability of fiberoptic-based technologies, the clinician is now capable of passing small tubes (called scopes) through natural passage ways of the human body (without actually surgically opening up the part), e.g. gastroscopy, cystoscopy, etc. These techniques, eventually culminate in taking small tissue samples (biopsies) which are sent to histopathology laboratories.

So, whenever, any sample from a human body is taken (either voided naturally or obtained by the clinician or the laboratorian), it is referred to the clinical laboratory for investigation. On receipt of a report from the laboratorian, the clinician, then, makes up his mind and starts a unidirectional or specific treatment against the disease thus diagnosed. It would not be wrong to designate medical laboratory personnel as the backbone of the clinicians. But, for these technologists, the clinicians would forever grope in the dark. Gone are the days when diabetes mellitus was presented with the classical triad of symptoms—increased thirst, hunger and urination; likewise, typhoid seldom presents with a step-ladder pattern fever. Blood testing is absolutely mandatory, to know that they exist, their severity and eventually, after treatment; to know that they are under control or cured. Investigations are diagnostic as well as prognostic tools.