Introduction to Chemical Pathology

At the end of this course, students should be able to: 1. explain biological variability and the effects of patient preparation prior to sample collection in order to enable students send suitable samples to the laboratory; 2. describe sample collection, random samples, timed collection, and use of special investigations requests, specimen/sample containers, difference between plasma, serum and whole blood, handling of CSF samples; 3. interpret clinical chemistry results, use of conversion factors for different units and reference intervals; 4. describe acid base homeostasis and disorders, sodium and water homeostasis and disorders, potassium homeostasis and disorders, calcium homeostasis and related disorders, uric acid metabolism and disorders; 5. enumerate potassium balance and disorders; and 6. list calcium, phosphate, magnesium and vitamin D disorders.

General clinical chemistry. General introduction to chemical pathology, branches of chemical pathology, the role of chemical pathology in the diagnosis, monitoring, detection of complication and determination of diseases, burden of non-communicable diseases, importance of reference interval/range, Gaussian distribution, normal distribution curve. Specimen handling and pre-analytical variables. Biological variability. Concept of diurnal rhythm, supracardian rhythm, modifiable and non-modifiable causes of analytical variability, and types of specimen collected and analysed by the chemical pathology laboratory. Patient preparation for chemical pathology investigations, random samples, timed collection, and use of special investigations requests, specimen/sample containers, difference between plasma, serum and whole blood, handling of CSF samples. Interpretation of numerical results. Units in clinical chemistry, SI and conventional units, interpreting clinical chemistry result, use of population specific reference interval, subject base reference interval, significant differences in results, sensitivity, specificity, diagnostic efficiency and odd’s ratio, negative and positive predictive values, handling and abnormal or incongruent laboratory result. Acid base homeostasis and disorders, sodium and water homeostasis and disorders, potassium homeostasis and disorders, calcium homeostasis and related disorders, uric acid metabolism and disorders. Water and sodium homeostasis and disorders. Potassium balance and disorders. Calcium, phosphate, magnesium and vitamin D disorders.