Stella A
Divisione di Ostetricia e Ginecologia, Ospedale Civile, Cittadella, Padova.
Minerva Ginecol. 1998 Jun;50(6):255-9.
Renal agenesis is thought to result from a lack of induction of the metanephric blastema by the ureteral bud. Bilateral renal agenesis/dysgenesis (BRA/D) is rare, occurring in only one or two per 10,000 births. Despite its being moreover a sporadic event, there is a male to female ratio of 2.5 to 1 and approximately 20-36% of BRA/D present a familial recurrence, for genetic transmission most probably autosomal dominant with incomplete penetrance and variable expression, termed hereditary renal adysplasia (HRA). A case of prenatal diagnosis by ultrasound of renal agenesis/dysgenesis (left renal agenesis and severe right multicystic dysplastic kidney) is described here. A woman in the 32nd week of pregnancy, who has never undergone any clinical and medical examination, presents at the ultrasound control. A male fetus was born from breech delivery at 34 weeks gestation, weighted 1950 g died after two hours because of severe pulmonary hypoplasia. Autopsy confirmed the antenatal diagnosis of left renal agenesis and right multicystic dysplastic kidney, that measured 42 x 31 x 25 mm, with bilateral complete absence of ureters and renal vessels. No other malformations were present. The infant's chromosomes were normal (46 XY). No specific chromosomal anomaly was identified in either parents. Both the parents had normal genitourinary ultrasound findings. In the wife's family pedigree, a sibling had asymptomatic unilateral renal agenesis, found at ultrasonography, and one maternal aunt had unilateral multicystic kidney and bicornuate uterus. Moreover one maternal uncle died at birth after preterm delivery from respiratory failure, unfortunately kidneys were never examined. Instead, no renal anomaly was identified in the husband's family history. The parents must be made aware not only of the inevitable fatal outcome for the fetus but also of the increased risk of recurrence in a subsequent pregnancy. On the basis of the literature, (of which this case is a further confirmation) it is underlined the necessity that all families of bilateral renal agenesis/dysgenesis patients-should have a detailed evaluation, including a detailed family history and ultrasound study of the kidneys and uterus; in fact all first-degree relatives have an increased risk of having silent genitourinary malformations.
肾缺如被认为是由于输尿管芽未能诱导后肾胚基所致。双侧肾缺如/发育不全（BRA/D）较为罕见，每10000例出生中仅发生一至两例。尽管它是散发性事件，但男女比例为2.5比1，约20 - 36%的BRA/D存在家族复发情况，其遗传方式很可能是常染色体显性遗传，具有不完全外显率和可变表达，称为遗传性肾发育异常（HRA）。本文描述了一例通过超声产前诊断肾缺如/发育不全（左肾缺如和严重的右多囊性发育不良肾）的病例。一名怀孕32周的女性，此前从未接受过任何临床和医学检查，前来接受超声检查。一名男性胎儿在妊娠34周时臀位分娩出生，体重1950克，因严重肺发育不全在两小时后死亡。尸检证实了产前诊断的左肾缺如和右多囊性发育不良肾，右肾大小为42×31×25毫米，双侧输尿管和肾血管完全缺失。未发现其他畸形。婴儿染色体正常（46，XY）。父母双方均未发现特定的染色体异常。父母双方的生殖泌尿系统超声检查结果均正常。在妻子的家族谱系中，一名兄弟姐妹经超声检查发现有无症状的单侧肾缺如，一名姨妈有单侧多囊肾和双角子宫。此外，一名舅舅早产出生后因呼吸衰竭在出生时死亡，遗憾的是肾脏未进行检查。而在丈夫的家族史中未发现肾异常。必须让父母不仅了解胎儿不可避免的致命结局，还要了解后续妊娠复发风险增加的情况。根据文献（本病例进一步证实了这一点），强调了所有双侧肾缺如/发育不全患者的家庭都应进行详细评估的必要性，包括详细的家族史以及肾脏和子宫的超声检查；事实上，所有一级亲属患隐匿性生殖泌尿系统畸形的风险都会增加。
