Which ATT will cause transient memory loss
**Core Concept**
Transient memory loss as a side effect of antitubercular therapy (ATT) is associated with the use of isoniazid, a first-line antitubercular medication. Isoniazid interferes with the synthesis of myelin, leading to neurotoxicity and cognitive impairment.
**Why the Correct Answer is Right**
Isoniazid inhibits the enzyme pyridoxal kinase, which is necessary for the conversion of vitamin B6 (pyridoxine) into its active form. This results in a deficiency of pyridoxal phosphate, a coenzyme required for the synthesis of myelin. The deficiency of myelin leads to neurotoxicity, manifesting as peripheral neuropathy and cognitive impairment, including transient memory loss.
**Why Each Wrong Option is Incorrect**
* **Option A:** Ethambutol is associated with optic neuritis, not transient memory loss.
* **Option B:** Rifampicin is a potent inducer of cytochrome P450 enzymes and has various side effects, but it is not typically associated with transient memory loss.
* **Option C:** Pyrazinamide is associated with hepatotoxicity, but not typically with transient memory loss.
**Clinical Pearl / High-Yield Fact**
Isoniazid-induced peripheral neuropathy and cognitive impairment can be prevented or managed with pyridoxine supplementation, highlighting the importance of monitoring for vitamin B6 deficiency in patients receiving isoniazid-based ATT.
**Correct Answer:** C.