H Gao, S Yan, SC Chan, L Sun

Abstract

Imperforate hymen (IH) is a rare malformation of the female reproductive tract. Diagnosis is often missed or delayed due to nonspecific symptoms or inadequate physical examination in early stages of life, sometime leading to serious consequences. A 2-day-old girl was found a cystic pelvic mass in on antenatal scans, initially suspected to be a teratoma. Postnatal ultrasound confirmed the presence of the cystic structure and bilateral hydronephrosis. Blood urea nitrogen and creatinine level were elevated and progressively worsen over time. A gynaecological examination revealed the absence of a vaginal opening with bulging at the vaginal introitus. The infant underwent hymenectomy, and the girl remained healthy throughout her follow-up visits. Carefully physical examination is crucial for early diagnosis and a multidisciplinary approach is necessary in paediatric hospital.

Introduction

Imperforate hymen (IH) is a rare malformation of the female reproductive tract, occurring in about 1 in every 1,000 female births.¹ IH can present with obstructive symptoms of the female genital and urinary tract during the perinatal, pediatric, or adolescent years. It is a rare cause of primary amenorrhea. Diagnosing IH in the fetal or neonatal period is particularly challenging, as differentiating pelvic or abdominal cystic masses due to IH from other causes is difficult. We report a case of a newborn girl with a cystic pelvic mass, highlighting the importance of a careful and comprehensive physical examination amongst paediatricians.

Case Report

A 2-day-old newborn girl, delivered vaginally at 39 weeks and 6 days, with a birth weight of 3000 grams, presented with a pelvic mass detected on antenatal scans at 38 weeks. The mass measured 6.0 x 5.0 x 5.6 cm and contained fluid and debris. Her Apgar score was 10 at both 1 and 5 minutes. Due to the antenatal findings, she was transferred to the neonatal department for further management at 2 hours of age for further evaluation. A paediatrician noted abdominal distention and consulted a paediatric surgeon, who suspected an abdominal tumor, such as a teratoma. Abdominal ultrasound revealed a fluid-debris mass located behind the bladder, along with bilateral hydronephrosis. Tumour marker levels were normal. Renal function tests showed elevated blood urea nitrogen (BUN) levels of 8.9 mmol/L (reference range 2.8-7.6 mmol/L) and creatinine levels of 80 μmol/L (reference range 21-65 μmol/L), which progressively increased over the next 2 days. A Paediatric and Adolescent Gynaecologist (PAG) was consulted. Examination by the PAG specialist found no vaginal opening and bulging at the vaginal introitus (Figure 1). Magnetic Resonance Imaging (MRI) and ultrasound showed that the cystic structure was located below the uterus, suggesting hydrocolpos (Figure 2). Additionally, bilateral hydroureter and mild hydronephrosis were also noted. The patient underwent hymenectomy under general anesthesia on 5 day of life, draining 250 milliliter white secretions. BUN and creatinine levels gradually return to normal by day 12 day of life. Follow-up ultrasound showed normal findings and the infant remained heathy.

Figure 1 Physical examination of the patient.

Figure 2 Ultrasound and magnetic resonance imaging results of the patient.

Discussion

IH typically remains asymptomatic until puberty, when obstruction of the outflow tract causes primary amenorrhoea. These patients may experience cyclical pelvic or abdominal pain and urinary retention. Additionally, many patients report genitourinary symptoms, including urinary frequency, dysuria, poor urinary stream and constipation. In severe cases, IH can lead to renal failure, urinary tract infections, or urosepsis. Some patients exhibit infrequent symptoms such as a palpable mass, back pain, and respiratory distress.² Physical examination of adolescents may reveal a bluish, bulging perineal mass.

Before birth, IH usually present as an abdominal or pelvic mass during the prenatal ultrasound. At birth, many cases go undiagnosed due to lack of symptoms. The main reason for seeking medical attention during the neonatal and infant periods is secondary hydrometrocolpos, which can present as irritability, distress, and other non-specific manifestations. Abdominal distention and urinary retention are rare, but some newborns present with lower limb swelling and complications from obstructive uropathy, leading to urosepsis, bladder perforation, or ascites. Shen et al reported a case of pyocolpos and lobar nephronia caused by an obstructed urinary tract.³ Expanding haematocolpos and haematometra can also exert pressure on the rectum, causing defecation difficulties in neonates. Physical examination of newborns may reveal a cystic white mass protruding from the perineum.

It is challenging to differentiate pelvic or abdominal cystic masses due to IH from other causes during the fetal or neonatal periods. When a cystic structure is observed in the lower abdomen or pelvis of a female fetus or neonate, it is important to determine whether it is an ovarian cyst. Giant ovarian serous cystadenomas have been reported in infants.⁴ Additionally, persistent cloaca, a severe anorectal malformation caused by failed partitioning of the genital, rectal, and urinary tracts should be considered.⁵ Furthermore, hydrometrocolpos, which can be caused by IH or vaginal atresia, is another potential cause of pelvic cystic masses.⁶ Unfortunately, timely diagnosis remains difficult in most cases.

Inadequate physical examination of neonates or children is a major contributor of diagnostic failure. A systematic physical examination improve diagnostic accuracy and optimises medical resource utilisation. Our experience underscores the importance of a multidisciplinary approach. IH is not a complex condition, yet a study revealed that only 64% of 139 paediatric chief residents correctly identified the hymen in prepubertal female genitalia photographs.⁷ Inadequate knowledge and limited experience contribute to diagnostic uncertainty, emphasizing the need for multidisciplinary collaboration.

Appropriate imaging techniques are crucial for accurate diagnosis. Ultrasound is a reasonable, cost-effective first line imaging modality. This could be due to the late accumulation of mucus in the vagina, not necessarily indicating that the ultrasound scan missed the findings. There is a good correlation between prenatal ultrasound images and MRI.⁸ MRI, with its superior contrast resolution, can distinguish uterine and vaginal components and is recommended in complex cases when resources permit. However, when resources are limited, ultrasound remains a feasible option.

Management of IH depends on the age at presentation and the severity of symptoms. Asymptomatic infants can be managed conservatively, with surgical intervention delayed until puberty. Spontaneous rupture of the hymen is possible. Hamouda et al reported two cases where the imperforate hymen ruptured spontaneously on the 4th and 7th days of life, with favorable outcome at 1 month of age.⁹ However, if obstructive symptoms are present, hymenectomy is recommended to prevent long-term complications. Surgical techniques include hymenectomy using cruciate or annular incisions or electrocautery. Due to the lack of estrogen, prepubertal children are at risk of recurrence post-hymenectomy. Therefore, annular sutures are recommended to prevent recurrence, reduce the risk of infection, and maintain hymenal patency during healing. A history of hymenectomy may be associated with significant long-term obstetrical and gynaecological complications, such as vaginal and perineal laceration-associated blood loss and preterm delivery.¹⁰

Conclusion

In conclusion, we presented a rare case of a newborn girl with a pelvic mass and bilateral hydronephrosis. This atypical presentation poses diagnostic challenge for pediatricians and pediatric surgeons. A gynaecological examination revealed the absence of a vaginal opening with bulging at the vaginal introitus. It highlights the importance of thorough examination. Routine neonatal examination should also include gynaecological assessment as a form of screening for an abdominal or pelvic mass. A multidisciplinary approach is necessary in paediatric hospital.

Conflict of Interest

The authors declare no conflicts of interest.

Acknowledgment

We would like to express our gratitude to Poh Ching Lee and Leek Mei Lim for their assistance in English language editing.

References

1. Abdelrahman HM, Jenkins SM, Feloney MP. Imperforate Hymen. StatPearls. Treasure Island (FL): StatPearls Publishing Copyright©2024, StatPearls Publishing LLC.; 2024.

2. Lee KH, Hong JS, Jung HJ, et al. Imperforate Hymen: A Comprehensive Systematic Review. J Clin Med 2019;8:56.

3. Shen MC, Yang LY. Imperforate hymen complicated with pyocolpos and lobar nephronia. J Chin Med Assoc 2006;69:224-7.

4. Vimal M, Chatterjee P, Nangia A, Choudhury SR. Giant Ovarian Serous Cystadenoma in an Infant: Report of a Rare Case. J Lab Physicians. 2021;13:388-90.

5. Shields LBE, White JT, Peppas DS, Rosenberg E. Challenges in the Prenatal Diagnosis of Cloaca. Glob Pediatr Health 2020;7:2333794X20958929.

6. Wang L, Chen L, Li D, Wang B, Yang Z. Characteristics of fetal physiological and pathological uterine effusion observed on prenatal ultrasonography: a case report. BMC Pregnancy Childbirth 2022;22:405.

7. Dubow SR, Giardino AP, Christian CW, Johnson CF. Do pediatric chief residents recognize details of prepubertal female genital anatomy: a national survey. Child Abuse Negl 2005;29:195-205.

8. Garcia Rodriguez R, Pérez González J, Garcia Delgado R, et al. Fetal hydrometrocolpos and congenital imperforate hymen: Prenatal and postnatal imaging features. J Clin Ultrasound 2018;46:549-52.

9. Ben Hamouda H, Ghanmi S, Soua H, Sfar MT. [Spontaneous rupture of the imperforate hymen in two newborns]. Arch Pediatr 2016;23:275-8.

10. Amitai E, Lior Y, Sheiner E, Saphier O, Leron E, Silberstein T. The impact of hymenectomy on future gynecological and obstetrical outcomes. J Matern Fetal Neonatal Med 2020;33:1400-4.