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Case Reports: Learning from unexpected outcome (positive or negative)
Schistosomiasis presenting as ruptured ectopic pregnancy
  1. Zenab Yusuf Tambawala1,
  2. Haneena Haneefa1,
  3. Badr Ahmed Abdul Hamid2 and
  4. Yusra Iqbal3
  1. 1Department of Obstetrics and Gynecology, Dubai Hospital, Dubai, UAE
  2. 2Department of Pathology and Genetics, Rashid Hospital, Dubai, UAE
  3. 3Dubai Medical College for Girls, Dubai, UAE
  1. Correspondence to Dr Zenab Yusuf Tambawala; drzenabtambawala{at}gmail.com

Abstract

A woman from sub-Saharan Africa living in the Middle East, presented with acute abdominal pain and COVID-19 infection. She underwent a laparotomy and left salpingectomy for a left tubal ruptured ectopic pregnancy. The histopathology report revealed the presence of tubal schistosomiasis in addition to the ectopic sac. The report emphasises the importance of considering female genital schistosomiasis as a potential cause of ectopic pregnancy and the need for collaboration between obstetricians and infectious disease physicians in the definitive treatment of the disease to reduce reproductive morbidity. This case report highlights the possibility of female genital schistosomiasis as a cause of ectopic pregnancy in women from endemic regions.

  • Obstetrics, gynaecology and fertility
  • Urinary and genital tract disorders

https://doi.org/10.1136/bcr-2023-255481

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    Background

    Human schistosomiasis, also known as bilharzia, is a parasitic infection that affects populations in more than 78 countries, most of them in sub-Saharan Africa. It is caused by blood flukes of the genus Schistosoma. There are five types of Schistosoma, from which Schistosoma mansoni, Schistosoma japonicum, Schistosoma mekongi and Schistosoma guinensis cause intestinal schistosomiasis. Schistosoma haematobium infection, formerly known as urinary schistosomiasis, renamed ‘urogenital schistosomiasis’ affects both the urinary and genital tracts in up to 75% of infected individuals.1 2 Urogenital schistosomiasis affects both males and females. In women, female genital schistosomiasis, a subtype of urogenital schistosomiasis, usually presents with dyspareunia, dysmenorrhoea, leucorrhoea, menstrual disorders, post-coital bleeding or simple contact bleeding (during an examination), cervicitis, endometritis and salpingitis. The disease also provokes gynaecological and obstetric complications such as early abortion, ectopic pregnancy and infertility.1 3

    Female genital schistosomiasis is a neglected tropical disease prevalent in sub-Saharan Africa and it has been estimated that 20–120 million women in this region live with the disease. S. haematobium is responsible for nearly half of the morbidity associated with schistosomiasis and is linked to at least 200 000 deaths per year.1 This highlights the significant morbidity and mortality caused by S. haematobium.4

    The COVID-19 pandemic compelled the WHO to temporarily suspend public health interventions for neglected tropical diseases. This was to limit transmission of COVID-19 to the neglected tropical disease endemic population. Community-based surveys, active case finding and mass drug administration of praziquantel for prevention and treatment of schistosomiasis were affected. This has resulted in a resurgence of neglected tropical diseases, including schistosomiasis, during and following the pandemic.5

    Women who are at high risk of female genital schistosomiasis are also at risk of infection with the HIV and human papillomavirus (HPV), which represents a serious threat to their reproductive and sexual health.6 7 Diagnosis of schistosomiasis requires a high level of suspicion, however, there is a lack of awareness about schistosomiasis in general and female genital schistosomiasis in particular among healthcare providers in both endemic and non-endemic regions.8–11 There is a need for increased awareness and education about female genital schistosomiasis among healthcare workers, as well as improved access to diagnostic and treatment services for affected communities.

    Case presentation

    A female patient, in her early 30s, presented to the general emergency department of a tertiary care hospital with a 1-week history of lower abdominal pain and nausea. The patient reported irregular menses in the preceding months, with her last menstrual period commencing 2 days prior to presentation. On examination by the general emergency physician, the patient was found to be alert and stable, however, there was evidence of suprapubic tenderness on abdominal examination. The patient was subsequently referred to the gynaecology emergency department for further investigation to exclude pregnancy and other potential gynaecological pathology as the cause of her symptoms.

    On further inquiry, the patient was found to be a sexually active nulliparous woman with a history of irregular menstrual cycles of variable duration, characterised by bleeding lasting for 3–4 days. There was no reported history of amenorrhoea preceding the current presentation. The patient also disclosed a history of using emergency contraceptive pills following each episode of intercourse. She had no complaints of haematuria, dyspareunia, or any medical or surgical history of relevance.

    On examination, the patient reported a pain score of 6 out of 10, without pallor and with stable vital signs. Abdominal examination was unremarkable. A vaginal examination revealed mild bleeding with cervical excitation. Laboratory tests including a complete blood count, beta human chorionic gonadotropin (beta HCG) titre and pelvic ultrasound were arranged. The laboratory results showed a haemoglobin level of 11.6 g/dL and a beta HCG level of 4130 mIU/mL. The pelvic ultrasound revealed that the uterus was mildly displaced to the left side, with an endometrium measuring 0.4 cm. Bilateral ovaries could not be identified. There was a heterogeneous lesion in the left adnexa, with a small gestational sac-like cystic lesion in the central portion, measuring 6.5×2.6 cm. Additionally, there was a moderate amount of free fluid with echogenic contents present in the lower abdomen and pelvis, raising the possibility of a ruptured ectopic pregnancy.

    While in the emergency department, awaiting the laboratory results, the patient’s pain score increased to 9 out of 10 and she developed tachycardia. She was transferred to the operation theatre for an emergency laparotomy which revealed a hemoperitoneum of 100 mL. The uterus, right fallopian tube and bilateral ovaries were normal. A ruptured left ectopic pregnancy was noted. A left salpingectomy was performed to remove the ectopic pregnancy and the fallopian tube.

    The patient had an uneventful postoperative recovery and was discharged home after 24 hours of observation following the surgery. She was scheduled for follow-up in the gynaecology clinic after 3 weeks. Histopathological examination of the tissue removed during the surgery confirmed a ruptured left tubal ectopic pregnancy with tubal schistosomiasis (figures 1 and 2). The patient was called back to the hospital for treatment of schistosomiasis.

    Figure 1
    Figure 1

    The tubal and peri-tubal tissue shows viable and partly calcified Schistosoma eggs (black arrows) with eosinophil-rich chronic inflammation and foreign body-type multinucleated giant cells (white arrows) engulfing some of the eggs (H&E stain, original magnification ×400).

    Figure 2
    Figure 2

    Tubal lumen fibrinous haemorrhagic ectopic pregnancy trophoblastic cells H&E ×200.

    Global health problem list

    • Challenges in the diagnosis of female genital schistosomiasis.

    • Female genital schistosomiasis as an underlying cause of obstetric and gynaecological complications.

    • Community health measures to eradicate female genital schistosomiasis.

    • Impact of COVID-19 pandemic on female genital schistosomiasis.

    Global health problem analysis

    Challenges in the diagnosis of female genital schistosomiasis

    Our patient, from West Africa, living in the Middle East, was unaware that she had schistosomiasis prior to her visit to the hospital. The physicians only became aware of the patient’s diagnosis of schistosomiasis after the histopathological findings of tubal ectopic pregnancy and fallopian tube scarring caused by Schistosoma eggs. The patient had irregular menstrual periods for a few months (which could have been caused by hormonal drugs), but no other symptoms of schistosomiasis were identified. As a result, diagnosing schistosomiasis would have required a high degree of suspicion. Following surgery, the patient was discharged within 24 hours, but the histopathology results were still pending. At the subsequent follow-up appointment, the patient was informed of the diagnosis of schistosomiasis. Despite recommendations for additional tests and prescribed medication, the patient failed to attend further evaluation or treatment sessions. Even though large populations in Africa are affected by it, female genital schistosomiasis is little known in other parts of the world. Urbanisation and travel for work and education can lead to the dispersal of populations affected with schistosomiasis and other neglected tropical diseases to places where healthcare workers may have limited knowledge about the condition. This can lead to missed diagnoses, incomplete or ineffective treatment, and further spread.11–13

    Schistosomiasis is highly endemic in this part of West Africa. Since measures to eradicate schistosomiasis were started in 2008 by the WHO, the prevalence rates of schistosomiasis have come down from 72.5% (1989) to 23.3% (2015).14 15 In sub-Saharan African countries, schistosomiasis poses a significant health burden, yet there is a notable lack of awareness regarding its reproductive health implications within endemic communities. Health education efforts concerning urogenital schistosomiasis must encompass not only symptoms but also the reproductive health consequences and the potential for HIV transmission. Unfortunately, urogenital and female genital schistosomiasis may go unnoticed by healthcare workers. Thus, there is a pressing need for nationwide campaigns aimed at raising awareness, monitoring and treatment of the neglected aspects of the disease.13 16

    Diagnosis of female genital schistosomiasis can be challenging as the symptoms are often absent, non-specific or may be mistaken for other gynaecological conditions. While microscopy of urine can detect eggs of S. haematobium in the urinary tract, the diagnosis of female genital schistosomiasis not only requires a high index of suspicion but also more specialised methods. Cervical swab samples can detect the presence of the parasite’s eggs. However, this method is not always reliable and may miss cases of female genital schistosomiasis.1 Genital self-sampling followed by pre-amplified PCR on room temperature-stored DNA is another method which can simplify diagnoses.17 The majority of these procedures are unavailable in endemic nations, making diagnosis more difficult.

    A colposcopy can help identify the grainy sandy patches, homogenous yellow sandy patches, rubbery papules and atypical vascular patterns that occur in the chronic form of genital schistosomiasis. S. haematobium is the most common cause of female genital schistosomiasis occurring in 50%–80% of parasitised females. Histopathological examination of surgical specimens has shown that S. haematobium ova can be found in all female genital organs; most commonly in the cervix and vagina but rarely in tubal specimens.18 19

    Clinicians should indeed consider the possibility of schistosomiasis and its associated complications when providing healthcare to women and girls from endemic areas. It is crucial to adapt diagnostic and treatment protocols specifically for female genital schistosomiasis and ensure that other conditions such as HPV, HIV and other sexually transmitted diseases are appropriately ruled out.6 7 20–22

    Female genital schistosomiasis as an underlying cause of obstetric and gynaecological complications

    Female genital schistosomiasis can lead to reproductive organ damage, infertility and an increased risk of ectopic pregnancy. Its association with tubal ectopic pregnancies can be severe, as seen in our patient.2

    Women affected by female genital schistosomiasis may exhibit signs and symptoms that resemble those of sexually transmitted infections.21 These can include a burning sensation in the genital area, vaginal bleeding, abnormal vaginal discharge, lower abdominal pain, haematuria (blood in the urine) and the presence of genital ulcers.2 Women develop uterine enlargement, menstrual disorders, cervicitis and infertility. Externally, vulvar or perianal lesions develop in 30% of women.4 These lesions can appear ulcerated, hypertrophic or even fistulous.2 4 However, many women, like our patient, are unaware of their condition, and female genital schistosomiasis remains a silent infection until it manifests as a major emergency.

    Clinicians need to consider schistosomiasis as a potential cause of pelvic inflammatory disease and ectopic pregnancy, even in patients from non-endemic regions. This consideration becomes particularly relevant if the patients have travelled or lived in endemic areas. Approximately, 10 million women in Africa have schistosomiasis during pregnancy. Female genital schistosomiasis can cause a variety of obstetric complications including spontaneous abortion, low birth weight, preterm birth, severe anaemia, low birth weight infants as well as increased infant and maternal mortality.23 24

    Women who have incorrect or missed diagnoses must face the ongoing physical and mental health consequences of female genital schistosomiasis, which are often associated with untreated infertility, the stigma of suspected sexually transmitted infection as well as the burden of HIV and HPV infection due to their increased susceptibility.25

    Community health measures to eradicate female genital schistosomiasis

    Schistosomiasis particularly affects agricultural and fishing populations. Women performing domestic chores in infested water, such as washing clothes, are also at risk. Hygiene and play habits make children vulnerable to infection. The distribution of schistosomiasis is very focal and determined by the presence of competent snail vectors, inadequate sanitation, and infected humans.1

    Implementing regular mass drug administration programmes in schools and endemic communities can significantly contribute to the prevention and control of schistosomiasis.26 These programmes, in combination with improved sanitation and hygiene practices, help reduce the overall transmission of the disease and mitigate the burden of female genital schistosomiasis. Additionally, health education and awareness campaigns play a vital role in promoting preventive measures and encouraging early treatment-seeking behaviour among affected populations.10 27 Praziquantel is the primary medication used for female genital schistosomiasis; its use has proven to be safe in both the obstetric and paediatric populations.28 29 Praziquantel, administered orally at doses of 20–40 mg/kg every 4–6 hours for 1 day, effectively eliminates adult worms.26 Praziquantel does not damage the schistosome eggs in tissues, preventing the release of egg antigens that could trigger harmful inflammatory immune responses.30

    Data for 2021 reveal that only 29.9% of people in need of praziquantel treatment were reached globally, with only 43.3% of school-aged children receiving preventive chemotherapy for schistosomiasis. Compared with pre-pandemic years, there has been a 38% decrease in availability of praziquantel. The COVID-19 pandemic has halted WHO mass drug administration campaigns in several endemic locations. The limited availability of praziquantel poses a significant obstacle to effectively controlling schistosomiasis.1

    Impact of COVID-19 pandemic on female genital schistosomiasis

    The COVID-19 pandemic has severely disrupted the WHO programme for control and eradication of neglected tropical diseases including schistosomiasis. These diseases disproportionately affect marginalised populations. The delay in mass drug administration and active case-finding due to pandemic-related challenges increases the resurgence of neglected tropical diseases, undermining the progress achieved over the last decade in their control and elimination.

    A 12-month delay in mass drug administration owing to the pandemic has pushed back the effort of schistosomiasis elimination by up to 2 years, particularly in locations where the target was on track to be met by 2030 without interruption. The length of this delay is influenced by factors such as initial prevalence of infection, adult prevalence and treatment programme duration. To counteract this setback, strategies have been developed to address the halt in WHO-recommended schistosomiasis therapies. These initiatives include administering praziquantel to 85% of school-age children and 40% of adults each year, up from 75% pre-pandemic coverage.5 Successful implementation of remedial strategies and their efficacy will determine whether neglected tropical diseases like schistosomiasis will be effectively controlled or not.

    Learning points

    • Female genitourinary schistosomiasis can cause serious complications such as ectopic pregnancy requiring urgent intervention.

    • Neglected tropical diseases such as schistosomiasis need to be prevented.

    • Healthcare providers should be knowledgeable about the clinical presentation, diagnostic methods and treatment options specific to schistosomiasis.

    • There can be an overlap in infection by HIV, human papillomavirus and female genital schistosomiasis in young women from areas where schistosomiasis is endemic.

    • Chemoprophylaxis with praziquantel in endemic communities is vital for reducing the prevalence of female genitourinary schistosomiasis.

    Ethics statements

    Patient consent for publication

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    Footnotes

    • Contributors ZYT, HH, BAAH and YI were responsible for drafting of the text, sourcing and editing of clinical images, investigation results, drawing original diagrams and algorithms, and critical revision for important intellectual content. ZYT, HH, BAAH and YI gave final approval of the manuscript.

    • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

    • Case reports provide a valuable learning resource for the scientific community and can indicate areas of interest for future research. They should not be used in isolation to guide treatment choices or public health policy.

    • Competing interests None declared.

    • Provenance and peer review Not commissioned; externally peer reviewed.