docKidneys Ureters Bladder Urethra Adrenal glands Internal and
download 
Report Transcription
Kidneys Ureters Bladder Urethra Adrenal glands Internal and
Martha L. Decker, MD Maternal Fetal Medicine Wake Forest University Fetal skin allows transudation of plasma into amniotic sac Urine produced as early as 9 weeks gestation Kidneys do not contribute significantly to amniotic fluid volume prior to 16 weeks gestation 7 weeks gestation Kidneys Ureters Bladder Urethra Adrenal glands Internal and external genitalia Normal kidneys are identifiable transabdominally in most fetuses by 20 weeks gestation (as early as 10‐12 wks) Normal kidneys generally span 4‐5 vertebral lkd ll b l bodies Length of normal kidney in mm is similar to gestational age in weeks 1 2 3 Pyelectasis Hydronephrosis Cystic kidneys Echogenic kidneys Absent kidneys Duplicated collecting system Progesterone effect on the ureter leads to inefficient removal of urine from pelvis and to vesicoureteral reflux due to poor tone in ureter Genetic disorder Early UPJ obstruction or pathological reflux Graupe et al. Clinics in PerinatologyVolume 28 • Number 2 • June 2001 210 fetuses with pyelectasis (>=4mm dilatation in AP plane in 2nd trimester) Likelihood ratio of 1.3 for trisomy 21 Pyelectasis, in conjunction with other clinical l i j i i h h li i l or sonographic parameters, warrants consideration for amniocentesis Benacerraf et al. Obstet Gynecol 76:58, 1990 4 AP measurement: < 4 mm – normal GA < 33 weeks, 4 – 9 mm – follow‐up after 33 weeks GA > 33 weeks, 7 – 9 mm – notify pediatricians ~ 10 mm – most likely a structural abnormality – follow with serial ultrasounds Pyelectasis Hydronephrosis Cystic kidneys Echogenic kidneys Absent kidneys Duplicated collecting system UVJ obstruction Ureterocele Urethral obstruction 5 6 Fetal bladder fills and empties every 30‐155 minutes Fetal bladder wall not normally seen when normal bladder is distended l bl dd d d d Normal ureters not visible Bladder outlet obstruction Posterior urethral valves (in male) Urethral atresia Other – Other like ureteroceles Sonographic findings: Bilateral hydronephrosis Hydroureter Distended bladder Oligohydramnios 7 Multicystic dysplastic kidney Cystic dysplasia Autosomal recessive polycystic kidney disease (ARPKD) Autosomal dominant polycystic kidney disease (ADPKD) Dilatation of the renal pelvis Hydronephrosis Cystic kidneys Echogenic kidneys h kd Absent kidneys Duplicated collecting system End result of early (first trimester) urinary tract obstruction 70‐80% unilateral Cysts of varying size f No communication between cysts, no uniformity in configuration Reniform contour is lost Non‐functioning 8 9 Occurs from obstructive uropathy in 2nd and 3rd trimester Common causes include UPJ obstruction Bladder outlet obstruction: Bladder outlet obstruction ▪ Urethral atresia ▪ PUV Results in irreversible renal damage Presence of cysts associated with dysplasia ie. echogenicity Usually few small cysts with small, bright kidney Right ureteral obstruction 10 Autosomal recessive; gene locus 6p Symmetrical enlargement of both kidneys with innumerable 1‐2 mm cysts May have hepatic involvement M h h ti i l t Diagnosable by 24 weeks Broad biologic variability, may not present until postnatal period Sonographic findings progress with advancing gestational age Gene mutation (PKD1) in 85% of affected European families on chromosome 16 y p p Severity of parental disease not predictive of offspring disease Cystic echogenic kidneys with normal amniotic fluid volume Systemic disorder: liver/pancreas/intracranial aneurysms/colonic diverticulae Difficult to differentiate from ARPKD Assess family history Renal ultrasound of both parents R l lt d f b th t If normal, consider ARPKD 11 Dilatation of the renal pelvis Hydronephrosis Cystic kidneys Echogenic kidneys h kd Absent kidneys Duplicated collecting system 12 Differential diagnosis: Normal variant Cystic dysplastic renal disease Finnish nephrosis Meckel‐Gruber syndrome Trisomy 13 Beckwith‐Wiedemann syndrome Dilatation of the renal pelvis Hydronephrosis Cystic kidneys Echogenic kidneys h kd Absent kidneys Duplicated collecting system M:F ratio 2.5:1 100% mortality Sonographic findings: Oligo/anhydramnios Bladder not visible Kidneys not visible Other anomalies common 13 14 Dilatation of the renal pelvis Hydronephrosis Cystic kidneys Echogenic kidneys Absent kidneys Duplicated collecting system 15 Kidneys Ureters Bladder Urethra h Adrenal glands Internal and external genitalia 16 Kidneys Ureters Bladder Urethra Adrenal glands Internal and external genitalia 17 18 19
