Therapy needs to address cardiopulmonary dysfunction that may be due directly to the effect of tick toxin and not just respiratory compromise caused by progressive respiratory muscle failure.

Renal venous renin ratio (RVRR) was measured in twenty hypertensive patients before removal of a kidney for unilateral, parenchymal renal disease. They were then followed for 1.3-9 y. Hypertension was cured or improved in six of eight patients with positive unstimulated and stimulated ratios, in none of five whose ratios became positive only on stimulation, and in one of seven with all ratios negative. Patients improved or cured by surgery had a significantly shorter duration of hypertension and a significantly lower serum creatinine after nephrectomy. Unstimulated RVRR was a reliable predictor of the effect of unilateral nephrectomy on blood pressure level.