Fatal Streptococcus Pyogenes Pneumonia

Discussion Previous recorded cases of renal failure due to ureteric obstruction in pregnancy' 4 fall into two groups: in the first there is obstruction to a solitary functioning kidney; and in the second, a large gravid uterus secondary to hydramnios or multiple pregnancies has resulted in bilateral ureteric obstruction. In 3 reported cases no obvious cause was detected. Obstructive uropathy in pregnancy has occurred between 21 and 39 weeks' gestation. In advanced pregnancy, treatment to date has been by induction and delivery. Earlier in gestation, patients have been treated with a temporary nephrostomy or a ureteral catheter and in one case by haemodialysis. Our first patient demonstrates that the early substitution of a percutaneous nephrostomy by an internal stent allows the pregnancy to continue without the need for external drainage with its associated inconvenience and risk of infection. Elective surgery was thus usefully deferred until the baby was old enough to be cared for by other members of the family. Unilateral renal obstruction in pregnancy without renal failure (cases 1 and 2) is probably a more common problem which has not been reported. The diagnosis of an acutely obstructed kidney in pregnancy depends largely upon the history and the findings on abdominal ultrasound examination. The latter investigation requires careful interpretation due to the existence of often considerable physiological dilatation of the upper urinary tract in pregnancy. Comparison ofthe degree ofdilatation ofthe affected kidney with the contralateral kidney is important, and the examination is also of value in detecting a urinary calculus which may be the cause of the obstruction. It is interesting to note that the postpregnancy IVPs in cases 2 and 3 were normal, with no demonstrable evidence of a primary pelvic hydronephrosis. It is well recognized, however, that obstruction of the pelviureteric junction can be intermittent, and in such cases urography or isotope renography is required when the patient has loin pain in order to make the diagnosis. An induced diuresis with Lasix at the time of radiology may reveal obstruction, but this was not observed in either case 2 or 3. It would seem from our experience with the cases reported here that a woman with a preexisting tendency to pelviureteric junction obstruction may be particularly prone to obstruct during pregnancy. This may-be contributed to by the attendant physiological dilatation of the upper urinary tract and the increased urine output in pregnancy. Cases 2 and 3 reveal that the prompt insertion ofan internal stent can relieve upper tract obstruction and obviate the need for a percutaneous nephrostomy5. In case 2 the insertion of a double-J stent proved an effective and safer alternative to induction of labour or probable emergency caesarean section. As illustrated by our patients, the stent is self-retaining and may remain in situ until successful delivery. In cases 2 and 3 the stents were voided spontaneously after 8 and 10 weeks respectively, and in the first case it was allowed to remain in position until one year after delivery. The use ofa prophylactic antibiotic is advisable, together with a high fluid intake, to prevent infection and the possible occlusion ofthe lumen and drainage holes in the stent.