Chloroquine influences renal function in rural Zimbabweans with acute transient fever.

To establish the effects of chloroquine on kidney function we monitored renal parameters in age and sex matched control subjects and patients who presented with acute transient fever. The patients were immediately treated with chloroquine diphosphate in the recommended dosage. Blood samples for creatinine, urea, Na+ and K+ determinations were collected before treatment (Day 0), on the 3rd day of treatment (Day 3) and two days after the last dose of chloroquine (Day 5). 24 h urine collections were collected for five consecutive days from the second day of treatment. Spot urine samples showed the absence of blood cells, bilirubin, glucose, protein and ketones. Examination of thick blood smears over three days did not reveal any forms of malaria parasites. Urinary tract infection in the patients was also excluded. Therefore, these patients were a suitable group to assess the effects of chloroquine on renal function. The blood pressure in females and males decreased significantly after two days of chloroquine treatment compared with Day 0. The plasma concentration of creatinine in females and females was increased by chloroquine 2 days after the last dose by comparison with the Day 0 (females, 66 +/- 2 mumol/L versus 83 +/- 2 mumol/L n = 20, p < 0.01 and males, 78 +/- 6 mumol/L versus 81 +/- 9 mumol/L, n = 20, p < 0.01). This was paralleled by a reduction in urinary creatinine excretion during the same period (females 15 +/- 1 mg/kg body weight/24 h versus 12 +/- 1 mg/kg body weight/24 h and males 23 +/- 3 mg/kg/24 h versus 18 +/- 2 mg/kg/24 h, p < 0.01 in both instances). Urinary urea excretion in females was reduced from 290 +/- 6 mumol/kg/24 h to 215 +/- 5 mumol/kg/24 h 2 days after treatment. The results of the study suggest that the effects of chloroquine in patients with acute transient fever include lowered urinary urea and creatinine excretion.