Can Moxifloxacin Be Continued with SGOT 160 and SGPT 63?
Yes, moxifloxacin can be continued in this patient, but with increased monitoring frequency and careful evaluation for alternative causes of liver enzyme elevation. The transaminase pattern (SGOT 160, SGPT 63) shows mild-to-moderate elevation with SGOT predominance, and these levels do not meet criteria for mandatory drug discontinuation.
Interpreting the Liver Enzyme Pattern
This patient has SGOT (AST) 160 U/L (
2.7× ULN assuming ULN of 60) and SGPT (ALT) 63 U/L (1.6× ULN assuming ULN of 40), representing a hepatocellular pattern with AST predominance 1The British Thoracic Society guidelines state that moxifloxacin should be avoided in patients with chronic liver disease (particularly Child-Pugh C) and in those with transaminase levels fivefold greater than the upper limit of normal 2
This patient's transaminases are well below the 5× ULN threshold that would contraindicate moxifloxacin 2
Evidence on Moxifloxacin and Hepatotoxicity
Moxifloxacin has been associated with transient increases in liver function tests as a common adverse effect, but acute hepatitis is rare 2
Research from the REMoxTB trial demonstrated that moxifloxacin-containing regimens actually had lower median peak ALT/AST levels compared to non-moxifloxacin regimens (p < 0.05), suggesting a hepatic-sparing effect 3
A population-based study found moxifloxacin associated with increased risk of acute liver injury requiring hospitalization (adjusted OR 2.20,95% CI 1.21-3.98), but this represented severe idiosyncratic reactions, not mild transaminase elevations 4
Management Algorithm for This Patient
Continue Moxifloxacin With Enhanced Monitoring:
Increase monitoring frequency to every 1-2 weeks initially, checking ALT, AST, alkaline phosphatase, and total bilirubin 5
Perform baseline ECG if not already done, as metabolic disturbances from hepatic dysfunction can potentiate QT prolongation with moxifloxacin 2, 6
Investigate Alternative Causes:
Review all concurrent medications and supplements for hepatotoxic potential 5
Assess for viral hepatitis (if not done at baseline), alcohol use, and non-alcoholic fatty liver disease 5, 1
Consider imaging (ultrasound) to evaluate for structural liver abnormalities 5
Discontinuation Thresholds:
Stop moxifloxacin if ALT/AST rises to ≥5× ULN, or if ALT/AST ≥3× ULN occurs with total bilirubin >2× ULN (Hy's Law criteria) 2
Discontinue immediately if patient develops symptoms of hepatitis (jaundice, right upper quadrant pain, nausea, fatigue) 6
Critical Considerations
The AST-predominant pattern (AST > ALT) may suggest alcohol use, non-alcoholic steatohepatitis, or cirrhosis rather than drug-induced injury, which typically shows ALT predominance 1
Moxifloxacin is not significantly affected by hepatic impairment in terms of clearance, as it undergoes both hepatic metabolism and renal excretion 6, 7
If the patient is on tuberculosis treatment, isoniazid is far more likely to be the culprit than moxifloxacin, as isoniazid-containing regimens showed higher median peak ALT/AST and earlier onset of elevation 3
Common Pitfalls to Avoid
Do not ignore mild elevations—they require investigation and monitoring, even if moxifloxacin is continued 5
Do not attribute all transaminase elevations to moxifloxacin without excluding other common causes like viral hepatitis, alcohol, or other hepatotoxic medications 5, 1
Do not continue moxifloxacin if combined transaminase and bilirubin elevations develop, as this signals severe drug-induced liver injury 5
Remember that more than 30% of mild transaminase elevations normalize spontaneously during follow-up, so serial monitoring is essential before making definitive attribution 8