Introduction
Table of Contents
“Rifampicin resistant indeterminate” refers to an unclear or inconclusive result in testing for resistance to the antibiotic rifampicin, often used in the treatment of tuberculosis (TB). Here’s a breakdown of the term:
Rifampicin
- Antibiotic: Rifampicin is a key antibiotic used to treat tuberculosis and other bacterial infections.
- Mechanism: It works by inhibiting the bacterial RNA polymerase, thus stopping the bacteria from synthesizing RNA and proteins, which are essential for their survival.
Resistant
- Resistance: Bacteria, such as Mycobacterium tuberculosis, develop resistance when they acquire mutations that allow them to survive despite the presence of the antibiotic.
- Clinical Implications: Rifampicin resistance is a critical concern because it often indicates multidrug-resistant TB (MDR-TB), which is more difficult to treat and requires alternative medication regimens.
Result and Cause
Indeterminate Result: This means the test did not provide a clear answer. The result is neither definitively resistant nor susceptible.

Causes:
- Technical Issues: There might be technical problems with the test, such as inadequate sample quality or issues during the testing procedure.
- Borderline Results: The bacterial strain might show borderline resistance, making it difficult to classify definitively.
- Mixed Infection: There might be a mixed infection with both resistant and susceptible strains of bacteria.
Implication
Further Testing: Additional testing is usually required to clarify the resistance status. This might include repeat testing, using different methods, or more sensitive molecular techniques. Treatment Decisions: An indeterminate result can complicate treatment decisions. Clinicians might need to rely on other clinical factors and possibly empirical treatment adjustments while awaiting more definitive results.

Summary
“Rifampicin resistant indeterminate” indicates an unclear result in determining whether the bacteria are resistant to rifampicin, necessitating further investigation to inform appropriate treatment strategies.