Comparative evaluation of the aminoglycoside antibiotics for systemic use

Treatment of visceral leishmaniasis in Kenya by aminosidine alone or combined with sodium stibogluconate

The treatment of leishmaniasis, as currently conducted in Kenya with sodium stibogluconate, is unsatisfactory as it is expensive, resistance and relapses may occur, and major adverse effects have been reported. Recently, aminosidine (paromomycin) sulphate has shown good antileishmanial activity on its own as well as synergism with pentavalent antimony, administered concurrently. The present study was designed to assess the effectiveness of parenteral aminosidine, alone or combined with sodium stibogluconate, in visceral leishmaniasis, compared to treatment by stibogluconate alone. 53 patients were allocated to the 3 therapeutic regimes. The presenting signs and symptoms of leishmaniasis were those commonly seen in the visceral form of the disease, particularly in Kenya. At termination, clinical cures were achieved in all 53 patients with no difference between treatment groups. Spleen aspirates revealed the best parasitological results in patients receiving the combined treatment, with only 13% failures (partial cures + relapses), as opposed to 21% failures with aminosidine alone and 45% with stibogluconate alone. Treatment with aminosidine alone was the cheapest and safest regime.

Comparison of venous and capillary blood sampling for the clinical determination of tobramycin serum concentrations

Tobramycin concentrations have been determined in serum from capillary, venous and arterial blood samples taken from 16 patients during and after surgery. In 73 paired samples the concentrations in capillary samples were not significantly different from those measured in venous samples. The small concentration differences were neither dependent upon sampling time nor core-peripheral temperature differences. In 26 paired samples, concentrations in capillary samples were not significantly different from those determined in arterial samples. We conclude that concentrations in capillary samples are precise and unbiased estimators of venous concentrations and may be used in the adjustment of tobramycin dosage regimens.

Tobramycin-furosemide interaction

A 70-year-old, 75-kg white female with a history of congestive heart failure was admitted with a two-week episode of progressive shortness of breath, increased abdominal distension, and ankle edema. Sputum Gram stains revealed gram-negative bacilli, and the patient was started on a loading dose of tobramycin 150 mg (2 mg/kg) over 30 minutes. The peak tobramycin level was 3.7 micrograms/ml drawn 45 minutes after the infusion was completed. Seven hours after the loading dose infusion, a trough level of 1.5 micrograms/ml was obtained. Based on the Sawchuk-Zaske method, the patient was started on a regimen of tobramycin 180 mg iv q8h. The following day, the patient received furosemide 120 mg iv. The trough and peak levels drawn 30 minutes before and after the fourth dose of tobramycin were 5.3 micrograms/ml and 16.2 micrograms/ml, respectively. The half-life of tobramycin remained relatively constant, while the volume of distribution decreased 40 percent after the administration of furosemide. This case illustrates that moderate doses of furosemide, administered to edematous patients receiving tobramycin, may cause an increase in both peak and trough levels, thus increasing the chances of ototoxicity and nephrotoxicity.