- Drug nephropathy are responsible 20% acute renal failure (IRA).
- More than a quarter of the patients should undergo renal replacement more d & rsquo; one in ten guards renal sequelae.
Nephropathy tubulointerstitial chronic and acute direct drug toxicity :
- They manifest as renal organic with urinary urea / urea blood < 5, decreased urine concentration of power, natriurèse conservée > 20mmol/l.
- Proteinuria t are zero or minimal, the blood pressure is normal, no sodium and water retention unless such impairment of renal function is important and / vents excessive intakes.
- Urine output may be normal or decreased (oliguria, anuria egg) rarely raised. L & rsquo; s general condition is preserved. There is no fever, or rash, ni hyperleucocytose ni hyperéosinophilie.
The main classes of drugs are responsible :
A- antibacterial :
1- aminoglycosides it is the most prescribed antibiotics nephrotoxic. The margin between the therapeutic and toxic dose is very étroite.Parmi them gentamicin seems most toxic and & rsquo; amikacin least toxic.
Aminoglycosides s & rsquo; eliminated by the kidneys and s & rsquo; accumulate in the lysosomes of cells of the proximal tubule where their presence will remain detectable for several weeks after the & rsquo; stopping treatment.
Aminoglycoside toxicity depends on multiple factors including the injected dose and the duration of treatment.
A pre-existing renal insufficiency even modest, recent treatment by the same or another aminoglycoside, prolonged treatment over 10 days require to regularly monitor kidney function and serum levels of & rsquo; antibiotic.
2- colimycine Eliminated only by the kidney. It is nephrotoxic from therapeutic doses. It is also neurotoxic. A good sign of overdose is the & rsquo; perioral paresthesia existence. Its parenteral administration should be reserved for absolute indications are exceptional.
3- Vancomycin Éiminée exclusively renally. It should regularly monitor kidney function in d & rsquo; prolonged treatment.
4- sulfonamides Filtered speaks glomerulus and reabsorbed and secreted party talks tube. Sparingly soluble their high dose administration results in a risk of massive precipitation in the renal tubule and in the urinary tract with micro or macroscopic hematuria, renal colic and sometimes trace anuria.
B- L’amphothérécine B :
A pus of antifungal used especially in the art and frequent cryptococos aspergillosis in particular immunocompromised patients with AIDS. She has a very long half-life and an almost obligatory renal toxicity.
C- iodinated contrast agents :
Toxic under specific conditions :
- Diabetes mellitus with renal insufficiency.
- Multiple myeloma with Bence Jones proteinuria.
- Application of high doses.
- repeated administrations within 5 days & rsquo; interval.
- pre-existing renal insufficiency caused some ilo.
- d & rsquo situations renal hypoperfusion.
- obstructive jaundice.
- It must be prevented when & rsquo; there are risk factors:
- Maintaining & rsquo; normal blood volume or slightly increased (500 to 1000ml saline before and after the & rsquo; review) ;
- Maintaining & rsquo; an abundant diuresis and compensated for and the 2 days after the & rsquo; review,
- A urine alkalinization (pH > 6) with sodium bicarbonate ;
- The correction of & rsquo; preexisting hyperuricemia ;
- Limiting doses of contrast agents ;
- The use of iso-osmolar products.
- Curative treatment is based on the same principles. L & rsquo; renal replacement is rarely required.
D- Anticancer and immunomodulatory :
New drugs and new treatment modalities allow survival prolonged in patients with various types of cancer.
L & rsquo; improving the oncologic prognosis balance by including kidney complications related to the toxicity of certain products or certain associations. This toxicity is substantially tubular.
L & rsquo; IRA can be prevented :
By limiting the dose if serum creatinine is greater than 120pmol / l and stopping the processing if it is greater than 160pmol / l; and speaks maintaining & rsquo; an abundant diuresis.
Common risk factors in renal interstitial acute partoxicité direct drugs :
- L & rsquo; pre-existing renal insufficiency.
- Diabetic nephropathy with renal insufficiency.
- L & rsquo; renal hypoperfusion whatever its cause : digestive losses, fever.
- Strict diet without salt, diuretics, effective hypovolemia by heart failure.
- decompensated cirrhosis, nephritic syndrome.
- Shock states.
- L & rsquo; association or succession in time of several nephrotoxic.
- Prolonged treatment.
- The high doses.
- The cholestatic jaundice.
Les néphropathies tubulo-interstitielles chroniques
Analgesics and anti-inflammatory drugs :
Sides intermittent treatment with a given product n & rsquo; not cause severe irreversible kidney damage, the analgesic associations and & rsquo; surunmode chronic aspirin administered on years are responsible for serious chronic interstitial nephropathy.
The renal tubulo-interstitielles dites immuno-allergic :
It s & rsquo; watch 10 days 3 weeks after & rsquo; & rsquo introduction, a drug used in a conventional dose or sooner s & rsquo; s it & rsquo; d & rsquo acts; reintroduction.
The diagnosis is easy if the table combines clinical and biological d & rsquo; hypersensitivity :
(fever,rash cutané, eosinophilia, increased IgEsériques), and if urinary symptoms is rich (renal failure without proteinuria or proteinuria with minimal, gross hematuria, eosinophiluria).
1- Think about it if renal sufficiency ins.
2- In renal insufficient
a- Dose titration
b- Ask for expert advice
3- Use caution in the elderly.
Cours du Pr Y. Kitouni – Faculty of Constantine