[The effect of long-term lithium treatment on kidney function]. / Wplyw dlugotrwalego podawania litu na czynnosc nerek.

In 1963 it was first demonstrated that long-term lithium administration exerts a "mood-stabilising" effect, preventing recurrences of mania and depression in bipolar affective disorder. Despite the introduction of many other drugs having mood-stabilising effect, lithium still remains the first choice drug for the prophylaxis of affective episodes in mood disorder. Lithium is eliminated nearly exclusively by the kidneys: lithium clearance is proportional to creatinine clearance and is influenced by natriuretic and antinatriuretic factors. Nowadays, nearly 40-year experience with long-term lithium treatment point to a possibility of nephrotoxic effects of this ion. Impaired urinary concentrating ability, which, in a few patients can reach an intensity of diabetes insipidus, can occur after several weeks of lithium administration. Favourable results in the treatment of diabetes insipidus have been obtained with amiloride, the drug which block epithelial sodium channel. However, after 10-20 years of treatment, lithium-induced interstitial nephropathy may be demonstrated in some patients, which, in small proportion of the latter may lead to end-stage renal disease. Lithium-induced hipercalcemia and nephrotic syndrome are rare complications of lithium therapy. In patients on long-term lithium therapy periodic monitoring of kidney function by measuring serum creatinine concentration and glomerular filtration rate is necessary. In case of detecting nephropathy, a discontinuation of lithium sho uld be considered. The patient in whom lithium was discontinued due to nephropathy should remain in nephrological treatment.

Screening for the markers of kidney damage in men and women on long-term lithium treatment.

BACKGROUND: Lithium is the most effective therapeutic modality for the prevention of recurrences in bipolar disorder. An important adverse effect of lithium, especially with long-term treatment, is a possibility of a toxic effect on kidney function. Therefore, the aim of the study was to assess kidney function in a group of long-term lithium-treated patients. MATERIAL/METHODS: The study comprised 80 patients with bipolar mood disorder (26 male, 54 female), aged 60 ± 11 years. They had been receiving lithium for 5-38 (16 ± 9) years. Random urine sample was examined for albumin and creatinine excretion, and urinary albumin to creatinine ratio (UACR) was calculated. Specific gravity of the urine sample was recorded. Serum concentration of creatinine was measured and estimated glomerular filtration rate (eGFR) was calculated. Serum concentration of albumin was also measured. RESULTS: Decreased eGFR values <60 ml/min/1.73 m² were found in 23% of patients, significantly more frequently in men that in women (38% vs. 16%, p=0.04). Elevated UACR values (>30 mg/g) were found in 25% of men and 12% of women, respectively. Serum albumin concentration >52 g/l was detected in 19% of patients (17% of men and 20% of women). Specific gravity of the urine, equal to or below 1.005, was recorded in 21% of men and 14% of women. CONCLUSIONS: The results confirm the opinion that screening for the markers of kidney damage should be performed in long-term lithium-treated patients for identification of persons with impaired kidney function. Male sex seems to be the risk factor for the development of kidney damage during long-term lithium treatment.