Interstitial nephritis associated with frusemide

Possible case of nafcillin-induced acute interstitial nephritis

PURPOSE

To report a case of acute interstitial nephritis (AIN) secondary to nafcillin.

SUMMARY

A 55-year-old Hispanic man (height, 63 in.; weight, 61.2 kg) with a history of deep vein thrombosis in the right lower extremity, hypertension, hyperlipidemia, and hepatitis C infection was admitted to the hospital with right-sided chest pain that radiated down his right arm and leg. The patient was diagnosed with methicillin-sensitive Staphylococcus aureus endocarditis. A renal ultrasound was performed on hospital day 9 after the patient developed acute renal failure and showed diffusely increasing echogenicity of the renal parenchymal bilaterally with an interpolar cyst in the left kidney. A urine analysis, serum chemistry panels, and complete blood counts were consistent with AIN. The patient received a total of seven days of nafcillin, and cefazolin was initiated. A renal ultrasound and renal biopsy were performed, which confirmed the diagnosis of AIN. The patient received short-term hemodialysis, after which his renal function slowly returned to baseline. He then underwent an aortic valve replacement and tricuspid valve repair. His antibiotics were changed to rifampin and vancomycin after methicillin-resistant S. aureus was found in an aortic valve culture on hospital day 26. Cefazolin was discontinued 3 days after rifampin and vancomycin were added. The patient received 18 more days of antibiotics and was discharged on the last day of therapy (hospital day 45).

CONCLUSION

A 55-year-old, critically ill man developed a possible case of nafcillin-induced AIN after receiving a 7-day course of treatment with the drug.

Risk Factors for Acute Renal Insufficiency Induced by Diuretics in Patients With Congestive Heart Failure

BACKGROUND

In patients with congestive heart failure (CHF), continuous diuretic therapy may result in acute renal insufficiency (ARI). This study examines factors contributing to this complication.

METHODS

We analyzed clinical data from 318 consecutive patients who were hospitalized for CHF. All were treated with diuretics and had echocardiography performed within 4 days of hospitalization. Systolic left ventricular (LV) dysfunction is defined as an ejection fraction less than 50%, and diastolic LV dysfunction, as an ejection fraction of 50% or greater in the presence of LV hypertrophy and a reversed E/A ratio.

RESULTS

ARI, defined as a 25% increase in serum creatinine level, occurred in 110 patients (35%) after diuretic therapy. Risk factors for ARI on univariate analyses were older age, higher baseline serum creatinine level, lower baseline serum sodium level, lower mean arterial pressure (MAP) during diuretic therapy, and greater doses and longer duration of diuretic therapy. In multivariate analyses, ARI occurred more frequently in patients with systolic (40%) than diastolic dysfunction (28%). The use of digoxin in patients with systolic LV dysfunction was observed to decrease the risk for ARI by 61%, independent of other agents used for the treatment of patients with CHF.

CONCLUSION

Age, baseline renal function and serum sodium concentration, MAP, and intensity of diuretic therapy can identify individuals at risk for ARI while receiving diuretic therapy for CHF. This complication is observed more often in individuals with systolic dysfunction, and its risk may be decreased with the use of digoxin.

Urinary C5b-9 excretion and clinical course in idiopathic human membranous nephropathy

Recent reports suggested that the presence of terminal complement complex (C5b-9) in urine from patients with idiopathic membranous nephropathy (IMN) may indicate on-going immunological damage. This report documents the relationship between C5b-9 excretion and clinical outcome in 35 adult patients with biopsy-proven IMN and progressively declining renal function. There were two groups of patients. Group I received one of three treatment regimens: prednisolone alone, prednisolone and chlorambucil, or prednisolone and cyclophosphamide (N = 22). Group II received no immunosuppressive therapy (N = 17). Three of the 18 patients receiving immunosuppressive drugs had more than one treatment regimen as they experienced a clinical relapse during the study period; hence 22 treatments were available for analysis. Urine samples were collected regularly and urinary C5b-9 (uC5b-9) was determined by ELISA. Both groups were similar with respect to age, sex distribution, and the duration of follow-up. An improvement in proteinuria and creatinine clearance was noted in the immunosuppressed group. Thirty-five patients were excreting C5b-9 initially (18 from group I and 17 from group II); 17 patients continued to excrete C5b-9 at the end of the observation period. These 17 patients had a significantly worse clinical outcome when compared to the 18 patients whose C5b-9 excretion became negative, either spontaneously or with treatment (P < 0.005). These results indicate that continuing C5b-9 excretion is correlated with a poor clinical outcome. They also suggest that uC5b-9 is a dynamic marker of ongoing immunological injury, and therefore may be useful in the initial assessment and monitoring of patients with IMN and in identifying patients who may derive benefit from immunosuppressive therapy.

Toxicology and carcinogenicity studies of diuretics in F344 rats and B6C3F1 mice. 2. Furosemide

Toxicology and carcinogenesis studies of furosemide, a widely used diuretic, were conducted by administering diets containing the drug to both sexes of F344 rats and B6C3F1 mice in 14-day, 13-week and 2-year studies. Deaths occurred among rats and mice receiving diets containing 46,000 ppm furosemide in 14-day studies, and animals given diets containing lower concentrations lost weight. No deaths were seen in 13-week studies using top concentrations ranging from 10,000 to 20,000 ppm, but animals at higher concentrations had lower weight gains than controls. Nephrosis in rats and mice was the only significant compound-related lesion observed in the prechronic studies. In 2-year studies, rats received diets containing 0, 350 or 700 ppm furosemide and mice received diets containing 0, 700 or 1400 ppm furosemide. Survival of dosed and control rats of both sexes and male mice was similar; survival of high-dose female mice was lower than controls. Nephropathy was increased in male rats and in male and female mice. In female mice, increased malignant tumors of the mammary gland were associated with furosemide administration. In male rats, marginal increases in tubular cell neoplasms of the kidney and in meningiomas of the brain were observed in dosed animals, but these were not considered to be related clearly to exposure to furosemide.