In an LDH assay, the diluted sample value is 120 IU after two successive dilutions. What should be the reported undiluted LDH value?

In an LDH assay, the diluted sample value is 120 IU after two successive dilutions. What should be the reported undiluted LDH value?

• A. 120 IU
• B. 6000 IU
• C. 2400 IU
• D. 60000 IU

Answer: (B)

In this LDH assay, you must report the undiluted value by accounting for how much the sample was diluted. When there are two successive dilutions, multiply the measured value by the product of the two dilution factors to get the undiluted concentration. Here, the diluted sample reads 120 IU after two dilutions. The combined dilution factor is 50 (for example, 1:5 followed by 1:10, giving 1:50 total). Multiply: 120 × 50 = 6000 IU. So the reported undiluted LDH value is 6000 IU.

In this LDH assay, you must report the undiluted value by accounting for how much the sample was diluted. When there are two successive dilutions, multiply the measured value by the product of the two dilution factors to get the undiluted concentration.

Here, the diluted sample reads 120 IU after two dilutions. The combined dilution factor is 50 (for example, 1:5 followed by 1:10, giving 1:50 total). Multiply: 120 × 50 = 6000 IU. So the reported undiluted LDH value is 6000 IU.