Liver failure, acute renal impairment

In a retrospective study of 1874 patients with type 2 diabetes taking metformin, 25% had contraindications, including acute myocardial infarction, cardiac failure, renal impairment, and chronic liver disease (33). However, contraindications often did not lead to withdrawal of metformin in 621 episodes, only 10% stopped taking it. Only 25 and 18% stopped taking metformin when they developed renal impairment or myocardial infarction, respectively. One patient developed lactic acidosis, but this may have been a consequence of myocardial infarction. 

Aspirin and similar NSAIDs can cause other toxic side effects if used improperly or if taken by patients who have preexisting diseases. For instance, serious hepato-toxicity is rare with normal therapeutic use, but high doses of aspirinlike drugs can produce adverse changes in hepatic function in patients with liver disease.85,99 Likewise, aspirin does not seem to cause renal disease in an individual with normal kidneys,84 but problems such as nephrotic syndrome, acute interstitial nephritis, and even acute renal failure have been observed when aspirin is given to patients with impaired renal function, or people with decreased body water (volume depletion).35,102... 

Patients with liver impairment, such as cirrhosis with portal hypertension (particularly alcoholic cirrhosis/hepatitis) or acute liver failure, are more susceptible to renal impairment than those without liver impairment. Care should be taken with any drug that is potentially nephrotoxic or could contribute to renal dysfunction in these types of patients. 

Oral acyclovir is a remarkably safe drug. Common side effects include nausea, vomiting, diarrhea, and abdominal pains. Additional side effects include skin rash, photosensitivity, headaches, dizziness, hallucinations, lethargy, confusion, seizures, and coma. Side effects are most frequent in patients with renal impairment. Rarer complications include anemia, leukopenia, thrombocytopenia, increases in blood urea and creatinine, acute renal failure, reversible increases in bilimbin and liver enzymes, hepatitis, and jaimdice. Cautious dosing and monitoring are recommended in elderly and immunocompromised patients and in patients with renal or liver disease. 

After exclusion of these differential diagnostic possibilities in liver diseases with renal symptoms, the likely diagnosis is hepatorenal syndrome. In the case of a severe and protracted course, this functional impairment of the kidneys can progress to true, acute renal failure, even with tubular necrosis. 

NSAIDs are known to inhibit prostaglandin synthesis and as a result may decrease renal blood flow, which in certain circumstances can lead to renal failure. Renal impairment is more likely to occur in the presence of renal vasoconstrictors. Tacrolimus is known to cause renal vasoconstriction and thus the combined effects of ibuprofen and tacrolimus may have led to acute renal failure. Both patients also had a degree of liver impairment, which the authors suggest may have potentiated the toxicity of tacrolimus with ibuprofen. 

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