- Weeks to months after starting therapy
- Crystalluria, hematuria, pyuria, flank pain, sometimes increased creatinine
|IDV-related nephrolithiasis is more common in adults (4%–43%) than in children (0%–20%).
ATV nephrolithiasis is rare.
|In adults, high serum IDV concentrations and elevated urine pH (>5.7) associated with persistent pyuria.
Unknown in children.
- Maintain adequate hydration.
- Obtain urinalysis at least every 6–12 months.
|Provide adequate hydration and pain control; consider using alternative ARV.
- Variable; in adults, weeks to months after initiation of therapy.
- Hypophosphatemia appears at a median of 18 months.
- Increased serum creatinine, proteinuria. Hypophosphatemia, usually asymptomatic, may present with bone and muscle pain, weakness.
- Renal failure, acute tubular necrosis, Fanconi syndrome, proximal renal tubulopathy, interstitial nephritis, nephrogenic diabetes insipidus with polyuria
- ~2% with increased serum creatinine
- ~0.5% with severe renal complications
- ~4% with hypophos-phatemia or proximal tubulopathy; higher in advanced HIV infection or concomitant use of ddI
|Risk May Be Increased in Children:
- aged >6 years
- of Black race, Hispanic/
- with advanced HIV infection
- with concurrent use of ddI or PIs (especially LPV/r), and
pre-existing renal dysfunction
- Risk increases with longer duration of TDF treatment.
|Monitor urine protein and glucose or urinalysis, and serum creatinine at intervals of every 3–6 months. For patients taking TDF, some panelists add serum phosphate to the list of routine labs to monitor.
In the presence of persistent proteinuria or glucosuria, or for symptoms of bone pain or muscle pain or weakness, also monitor serum phosphate
Because toxicity risk increases with duration of TDF treatment, frequency of monitoring should not decrease with time. While unproven, routine monitoring intervals of every 3–6 months might be considered. Abnormal values should be confirmed by repeat testing, and frequency of monitoring can be increased if abnormalities are found and TDF is continued.
|If TDF is the likely cause, consider using alternative ARV.