Definition: Hydrocolpos is the distension of the vagina by fluid, other than blood or pus, resulting in a cystic mass in the lower abdomen. During fetal life, hydrocolpos involves the dilatation of the vagina due to obstruction of the genital tract, leading to accumulation of secretions. If there is also uterine distension it is called hydrometrocolpos1.
During fetal life, hydrocolpos and hydrometrocolpos arise from accumulation of secretions from the productive glands caused by different etiologies: -obstruction of the vagina by a midplane transverse vaginal septum -vaginal atresia with accumulation of urine caused by a stenotic urogenital sinus and associated vesical-vaginal fistulas, vesical-uterine fistulas, urethral-vaginal fistulas or cloacal anomalies2.
Congenital imperforate hymen is an external urogenital anomaly3. An imperforate hymen is usually detected in the neonatal period when the infant presents with physical signs of lower abdominal swelling and a characteristic bulging membrane at the introitus1. It can also manifest at menarche as either cyclic abdominal pain with pelvic distension or urinary obstruction4.
We report a case of hydrocolpos associated with unilateral kidney dysplasia in which an imperforate hymen was suspected in a fetus at 28 weeks. It appeared in utero as a thin membrane that distended the vagina and spread the labia majora due to retained secretions. At 34 weeks, the hydrocolpos became a hydrometrocolpos. A renal abnormality was also seen, representing either a right multicystic dysplastic kidney or cystic dysplasia. After delivery, the diagnosis was found not to be an imperforate hymen, but rather a hemi-vagina or midplane longitudinal vaginal septum with accumulation of urine, probably caused by uretero-vaginal fistulas2.
Case Report: A 28-year-old woman, G3P2, was referred at 28 weeks to our institution due to a suspicion of fetal renal abnormality detected on a prenatal scan at 24 weeks. The family history and course of pregnancy up to that time were uneventful. An earlier scan at 13 weeks was normal as was the triple test at 16 weeks. A targeted ultrasound examination was performed in our unit at 28 weeks. The examination demonstrated an abnormal, highly echogenic right fetal kidney. It contained two large cysts and multiple peripheral cysts. The left kidney was normal in size and echogenicity. Fetal biometry was within the normal range for gestational age. Otherwise, an anechoic, distended vagina situated posterior to the normal bladder and anterior to the rectum was discovered. At the distal end of the vagina, a thin membrane bulged through the perineum and spread the major labia. Uterine distension was not observed. The obstructed vaginal canal measured 8 x 8 x 18 mm. The prenatal diagnosis of a congenital imperforate hymen with hydrocolpos and a multicystic dysplasia on right kidney was suspected. There were associated anomalies. A MRI confirmed the diagnosis. Karyotyping was offered and chromosomal analysis revealed a normal 46 XX karyotype. Maternal serological testing was negative. On follow-up scans at 30, 32 and 34 weeks, the appearance of the interlabial membrane became more impressive but the distension of the vagina remained stable. At 36 weeks, a detailed scan revealed a female fetus with retrovesical non-septated cystic structure. Fetal echocardiography was normal. At 38 weeks, a cesarean was performed and a 3400 g female infant was delivered. The newborn was admitted to the neonatal intensive care unit for surveillance and further investigation. On day 2, a renal scan showed a 3 cm right kidney with multiple cysts and without residual parenchyme. A retrovesical fluid-filled non septated mass of 30 x 10 x 10 mm was observed without left hydronephrosis. The prenatal diagnosis was not confirmed at birth by gynecologic examination. Indeed physical examination showed left vaginal distension with right abdominal distension caused by dystrophic kidney, the hymen was normal. An incision was performed inside the vagina, on the left, behind the hymen, resulted in complete disappearance of the accumulated vaginal and uterine fluid. The fluid could not have a correct analysis, but seemed urine. Three months later, the baby has a good health.
History: Winderl et al detected by ultrasonography one case (1995), one earliest case of hydrocolpos1. Mirk (1994) described one case and Respondek-Liberska at 1997. Geipel described one case at 34 weeks.
Prevalence: Hydrocolpos and hydrometrocolpos account for 15% of abdominal masses in female neonates, surpassed in frequency by hydronephrosis5-6. The estimated global prevalence is 2:10,000. The estimated incidence of hydrocolpos is 0.6:10,000 4-6. There are two types:
-
The urinary type is often associated with a persistent urogenital sinus or cloacal anomaly (as cloacal dysgenesis)7.
-
The secretory type, a large amount of mucoid material collects in the genital tract fluid and is the result of an excessive secretion by uterine gland, in response of maternal estrogenic hormones6. In this case, an imperforate hymen is mostly a sporadic and isolated malformation with a reported incidence of 0.014 %8.
Etiology: The obstruction can be due to a transverse vaginal septum, or vaginal or cervical atresia. Literature reports an occasional association with other congenital anomalies; simple imperforate hymen is almost always an isolated finding. Nevertheless, it is essential to recognize hydrometrocolpos and hydrocolpos.
Pathogenesis: During fetal life, the lumen of the vagina is separated from the cavity of the urogenital sinus by the hymen, which is usually ruptures during the perinatal period and remains as a fold of mucous membrane around the entrance to the vagina. Failure of this membrane to rupture results in an imperforate hymen. There is then significant accumulation of fetal cervical and vaginal secretions that develop secondary to circulating maternal oestrogen1. The result is hydrocolpos or hydrometrocolpos. Vaginal outflow obstruction leading to accumulate of secretions and subsequent hydro (metro) colpos might be secondary to the presence of a transverse vaginal septum, vaginal atresia or imperforate hymen, often as a result of Müllerian duct failure4.
Ultrasound Findings: As ultrasound becomes more and more reliable, prenatal diagnosis of a anomaly is possible as early as in the second trimester as in our case. Nevertheless during pregnancy hydrometrocolpos is frequently associated by urinary tract obstruction, causing hydronephrosis, oligohydramnios. So, it requires a systematic evaluation of the fetus, as a high number of these females may present with associated malformations and syndromes. Paradoxically, about our case, the first sign discovered was the kidney anomaly. Hydrocolpos is almost always an isolated finding. But the following associated anomalies can be seen9:
-
Bifid clitoris4
-
Polydactyly11
-
Ureteral duplicationHypoplastic kidney with ectopic ureter; urethral membrane;
-
Multicystic dysplastic kidney2
-
Imperforate anus10
About our case, we believe that the baby has certainly an ureteral duplication with ectopic ureter and vaginal insertion.
Implications for Targeted Examinations: With careful antenatal sonographic evaluation of the female perineum, identification of a thin protruding membrane consistent with imperforate hymen can be made. Nevertheless, it is important to perform a detail scan because some syndromes can be associated with hydro (metro)colpos9-10. McKusick-Kaufman9 associates hydrometrocolpos, congenital heart disease and polydactyly. It is an inherited autosomal recessive. Other associated malformations such as an imperforate anus, a recto-vaginal fistula, a persistent urogenital sinus, polycystic kidneys, renal hypoplasia and an urethrovaginal fistula have also been reported.
Differential Diagnosis: In our case, different diagnosis should be considered:
-
Congenital imperfurate hymen : is an external urogenital anomaly that has a small differential diagnosis. It must be distinguished from: labial fusion or labial adhesion
-
Vaginal atresia or agenesia
-
Transverse vaginal septum
-
Vaginal cyst
-
Hymeneal cyst of hymenal skin tag
-
Paraurethral cyst or Skene ducts cyst: it is a cystic mass located to right or left of the urethral meatus, which is approximatively 1 cm in diameter. These cyst are generally asymptomatic and disappear spontaneously 11. Only 28 cases have been reported in the English literature.
-
Distended urinary bladder (Obstruction of the posterior valve with megacystis)
-
Cloacal dysgenesis sequence: Cloacal dystrophy or persistent cloaca is a rare developmental defect affecting pelvic embryogenesis resulting in the persistence of a common cloaca receiving ureters, ileum and rudimentary hindgut in association with a wide range of urogenital tract anomalies, spinal dysraphism and imperforate anus5. The frequency is 1/200 000.
-
Others: Ovarians neoplasm; sigmoid duplications; Omental cyst; Mesenteric cyst. Cystic sacrococcygeal teratoma anterior meningocele5.
Associated Anomalies: Hydrocolpos can be associated (1/3) with:
-
Anomalies of the urinary system: Müllerian duct dysplasia, Müllerian hypoplasia, Renal agenesis, renal ectopy
-
Several deformities of the spine and the extremities are also common.
-
Imperforate hymen: which is usually isolated. Nevertheless imperfurate hymen can be associated with bifid clitoris, polydactyly, ureter duplication, hypoplastic kidney with ectopic ureter, multicystic dysplastic kidney, imperforate anus, ureteral membrane. The presence of prenatally detected hydro (metro) colpos warrants a systematic evaluation of fetal and neonatal anatomy to rule out a large variety of possibly associated malformations and syndromes.
-
Fryns wrote that the high resolution chromosome studies should be systematically performed in all female newborns with hydrometrocolpos, especially if associated dysmorphic or malformative stigmata are present (Indeed Fryns discovered one case of Trichorhino-phalangeal syndrome type II or langer-Giedon syndrome)9.
Prognosis: The prognosis of a simple hydrocolpos is excellent but familial recurrence has been observed. By surgical incision of the bulging membrane, the trapped utero-vaginal secretions are drained. However, if vaginal obstruction is caused by a mild plane transverse septum or vaginal atresia, the prognosis largely depends on the presence and severity of associated disorders. When there is hydrometrocolpos, retrograde passage of the secretions through the Fallopian tube into the peritoneal cavity led to an aseptic peritonitis and secondary ascites especially during the third trimester6. The postnatal course might be complicated by cardio-respiratory distress secondary to marked abdominal distension.
Management: Hydrocolpos or hydrometrocolpos can be diagnosed early during the pregnancy, as the second trimester. Because of the renal anomaly associated, it is suggested that the presence of prenatally diagnosed imperforate hymen warrants a careful survey of the remaining fetal anatomy to rule out associated abnormalities. The establishment of a correct preoperative diagnosis is important, but difficult. Incision after delivery of the imperforate hymen resulted in a complete resolution of the fluid accumulation. If complicated hydrometrocolpos or hydrocolpos arrived, management is immediately incision and drainage to establish vaginal patency. Neonatal hydrometrocolpos can be indeed a surgical emergency. The abdominal distension resulting from an intra-abdominal cystic mass may cause respiratory distress, urinary tract obstruction persistent pressure on the inferior vena cava and lower limb edema4.
Long-term follow up is necessary because the distended hypertrophic vagina can develop infection. After delivery, the girl newborn must be observed because abnormal uterus can be discovered (uterus didelphys, septate vagina). But vaginal catheterization for hydrometrocolpos and surgical correction give good results.
Conclusion: For conclusion, ultrasonography remains the most widely used diagnostic imaging technique for routine evaluation of the fetus. Nevertheless, the ability of ultrasonography to detect fetal anomalies is limited in some cases, (maternal obesity, oligohydramnios, and inappropriate fetal lie). So MRI enables high quality fetal images to be acquired. MRI is helpful for the diagnosis of pelvis anomalies, but not in all cases as in our case. In our case, the scans established more precise pictures than MRI pictures, but not a more precise diagnosis.
Left image: Parasagital view of the kidney at 28 weeks. showing a normal left kidney and a polycystic right kidney with no corticomedular differenciation.