Less-affected Side Research Articles

Experience with renal vein renin ratios in the identification of a pressor kidney.

The positive, preoperative recognition of a pressor kidney has many important ramifications, the most important being the ability to predict a reduction in blood pressure following surgical reconstruction or nephrectomy. One hundred forty hypertensive patients were selected for study for renal artery stenosis by measuring the differential plasma renin activity by either radioimmunoassay or bioassay. Bilateral renal vein renin determinations and renal arteriography were made consecutively in supine position and without stimulation of renin secretion. Unilateral or bilateral renal artery stenosis was found in 55 patients (39%). Twenty-eight of the 55 patients (51%) were treated surgically. Eighteen patients (64%) were cured of hypertension and seven (25%) were improved. All but one of the surgically treated patients had renal vein renin ratios of greater than 1.3 on the affected side over the unaffected or less-affected side. Increasing the ratio to greater than 1.5 or greater than 2.0 as a criterion for selection of patients for operation would not have decreased the failure rate. If used as the only criterion, increasing the ratios would have resulted in nonsurgical treatment of up to 50% of the patients cured or improved by surgery. Stimulation of renin secretion, although not used in this study, has been shown by others to more accurately identify a pressor kidney by increasing differential renal vein renin ratios. Although a combination of renin activity with renal plasma flow may lead to more accurate diagnosis, a careful clinical evaluation has not yet been replaced as the best method of selection of the patients for operation.

Multiple pulmonary hydatid cysts.

THE LUNG is the second commonest site in man, where the intermediate larval-cysticercal stage of Echinococcus granulosus develops. It is not unusual to find more than one cyst in the lung in man. However, the successful removal of more than two cysts from the lung is exceptionally rare. The incidence of hydatids occurring in lungs varies in different countries (Spencer, 1962), viz: Greece 30% (Toole et al., 1953) Australia 25% France 9% (Barrett) New Zealand 40% A survey of hydatid disease in the Waikato Hospital Board area from 1942 to 1959 (New Zealand) by Ellis Dick (1962-63) showed that 124 cases were treated and the distribution among them was as follows: liver-55 lung-49 lung and liver combined-10 However, the incidence of multiple pulmonary hydatid cysts was rarely mentioned. d'Abreu & Lambert Rogers (1938) reported the first case of two cysts, one on each side of the lung. Borrie (1962-63), in his report of fifty cases of thoracic hydatid disease, mentions that only seven cases of multiple cysts were seen. The maximum number of cysts was only two, in the seven cases seen. Barrett (1960) reports that the largest number of primary hydatid cysts in the lung was three. One of the three was a simple cyst and the remaining two were ruptured in the bronchial tree and the patient died. Thomas (1965) reports seeing three cysts in the lungs. Deve (Barrett, 1960) analysed thirty-one cases of multiple metastatic hydatid cysts in the lungs and found that the primary cyst was in the heart (twenty cases), liver (eight cases) and iliac bones (three cases). Thus the successful removal of three cysts or more from the lung is very exceptional. The following is a report of three cases of pulmonary hydatid cysts, successfully operated upon, where the number of cysts removed was more than two in each case. Case 1 Mr S., a 40-year-old male, had, at the time of admission, two cysts in the right lung (upper and lower lobe one each), four cysts in the left lung (both lobes involved) and two cysts in the liver. The two cysts on the right side were unequal in size. However, all the cysts on the left side and one on the right (upper lobe) appeared to be almost equal in size, signifying that they were all of almost the same age (Fig. 1). It was decided to do the right thoracotomy first in order to release the right lung, the lessaffected side (10 September 1963). Both cysts were removed and ruptured during removal. The patient went into anaphylactic shock but soon recovered. The second operation (29 October 1963), a laparotomy by a Rutherford Morrison incision on the right side, consisted of marsupialization of a large cyst in the liver. The second cyst, a smaller one, 1 X I1 in., was just attached to the free margin of the liver and was therefore excised with a portion of the liver. Haemostasis was achieved