Chemical Pathology

Clinical Biochemistry (Chemical Pathology)

Head of Department: Dr. Saroja Siriwardene

The Clinical Biochemistry section carries the largest workload in any medical laboratory. It performs chemical analysis of blood, urine and body fluids for a wide range of chemical constituents, selected and requested by a medical practitioner. Once a disease is suspected, the biochemical tests become useful in multiple ways: viz. identify the disease, follow-up the course of the current illness, indications of prognosis, monitor the long-term progress and give early warning on recurrence.

The categories of tests include the determination of the concentration of glucose, electrolytes (Na / K), lipids (cholesterol / triglycerides), proteins (albumin / immunoglobulins / CRP), enzymes (amylase / lipase), hormones (thyroxine / cortisol), nitrogenous waste products (creatinine / urea), tumour markers (thyroglobulin / PSA), cardiac markers (cardiac troponin I and T), trace metals (copper / zinc), therapeutic drugs (tacrolimus, valproate), glycated proteins (HbA1c and fructosamine) and vitamins (B12, D) in blood.

Early morning or random urine samples are commonly analysed for microalbumin, proteins, electrolytes and osmolality while supporting the results with urine creatinine to provide a meaningful analyte:creatinine ratio where relevant (e.g. albumin:creatinine ratio). Accurate 24-hour urine samples are required for the measurement of creatinine clearance and to evaluate the daily renal loss of chemical components.

In order to provide comprehensive pathology reports on target organs or functions, tests are grouped into profiles (e.g. renal, liver, cardiac, lipid and iron profiles). Dynamic endocrine function tests (e.g. short Synacthen test) facilitate early diagnosis of endocrine disorders.

Accuracy and Precision of tests are two main features that would distinguish a well performing laboratory above others. LHD ensures these qualities by using fully-automated analysers together with dedicated, certified reagents from internationally recognised suppliers. The laboratory staff is well-trained and are supervised by an experienced Biochemist (MSc) and a Consultant Chemical Pathologist (MD Chemical Pathology), both working full-time. There is provision for medical practitioners to get laboratory assistance in interpreting difficult case scenarios by providing the relevant clinical history.

LHD is accredited by the College of American Pathologists (CAP) and the Sri Lanka Accreditation Board (SLAB) ranking it as the Number one medical laboratory in Sri Lanka for the quality of service it offers.