On Demand Medical Testing

Hepatitis B surface antibody (HBsAb)usually appears about 4 weeks after HBsAg disappears. The presence of this antibody means that the infection is at the end of its active stage and you cannot pass the virus to others (you are no longer contagious). This antibody also protects you from getting HBV again in the future. The test is done to determine the need for vaccination—the antibody will be present after receiving the HBV vaccine series, showing that you have protection (immunity) from the virus. Occasionally your test may show that you have both the HBsAb antibodies and HBsAg antigen. In this case you are still contagious.

HCV RIBA is an additional test that detects antibodies to HCV. This test can tell whether a positive result was caused by an actual HCV infection or whether the result was a false-positive. This test may be done to double-check a positive EIA test result.

Elevations in serum lactate dehydrogenase occur from myocardial infarction, liver disease, pernicious and megaloblastic anemia, pulmonary emboli, malignancies, and muscular dystrophy. 

Leptin is an adipocyte-derived hormone that is essential for normal body weight regulation. Leptin production is under neuroendocrine control so that serum concentrations vary directly with the amount of triglycerides stored in adipose tissue depots.

A lipase test measures the amount of this enzyme in a blood sample. High amounts of lipase may be found in the blood when the pancreas is damaged or when the tube leading from the pancreas (pancreatic duct) to the beginning of the small intestine is blocked.

A lipid panel is a blood test that measures lipids—fats and fatty substances used as a source of energy by your body. Lipids include cholesterol, triglycerides, high-

Prealbumin is decreased in protein-calorie malnutrition, liver disease, and acute inflammation. It may be used as an indicator of nutritional requirements and response to therapy during total parenteral nutrition and as a biochemical marker of nutritional adequacy in premature infants.

Screening test for abnormalities of coagulation factors that are involved in the extrinsic pathway. Also used to monitor effects of Warfarin therapy and to study patients with hereditary and acquired clotting disorders.

Albumin, BUN/Creatinine Ratio (calculated), Calcium, Carbon Dioxide, Creatinine, Estimated Glomerular Filtration Rate (calculated), Glucose, Phosphate (as Phosphorus), Potassium, Sodium, Urea Nitrogen

Selenium is an element of parenteral nutrition. Monitoring the Selenium concentration is useful in assessing parenteral nutrition, especially recent intake. Concentrations are also monitored in children with proprionic acidemia who require special diets with supplements.