Rare co-occurrence of appendicitis, ovarian dermoid cyst with torsion: a case report

Abstract

Introduction:

Simultaneous presentation of acute appendicitis and ovarian torsion is rare and requires urgent surgical intervention due to the high risk of complications, including sepsis and mortality. While adnexal torsion is a known cause of acute abdomen in reproductive-age women, co-presentation with appendicitis is exceptionally uncommon. This case underlines the importance of considering gynecological differentials in women presenting with acute abdominal pain.

Case presentation:

A 39-year-old woman presented with right lower abdominal pain, fever, and vomiting. Initially diagnosed with an appendicular lump, she was managed conservatively and discharged after symptomatic improvement. Upon recurrence of symptoms, imaging revealed an ovarian dermoid cyst with torsion. Exploratory laparotomy identified a gangrenous ovary with a twisted cyst and adherent appendix. Histopathology confirmed acute appendicitis and a benign dermoid cyst.

Discussion:

Adnexal torsion occurs when the ovary and fallopian tube twist around their ligaments, often caused by ovarian cysts like dermoid cysts. These cysts are common in young women and can lead to acute abdominal pain, requiring urgent surgery to prevent ovarian damage. Diagnosis is challenging, as symptoms mimic other conditions like appendicitis. Imaging such as ultrasonography or computed tomography is used, and treatment involves surgical untwisting or removal of affected tissues. Torsion sometimes affects nearby organs, like an appendix.

Conclusion:

This case highlights the rare occurrence of simultaneous appendicitis and ovarian torsion, emphasizing the importance of early diagnosis and surgical intervention.

Introduction

Acute appendicitis and ovarian lesion torsion together are very uncommon and should be treated surgically^[1]. Early diagnosis and treatment are necessary for patients with both ovarian lesion torsion and appendicitis, since they are at risk for sepsis and higher mortality rates^[2]. In women, adnexal torsion is a major cause of acute abdominal pain; up to 3% of women who arrive at an emergency room with severe abdominal pain have this condition^[3]. Although it can happen to individuals at any age, from prenatal to postmenopausal, it most frequently affects women who are of reproductive age, including who are pregnant. The diagnosis is only made conclusively during surgery, and in certain cases, it may be misdiagnosed if they are not brought to the operating room; therefore, the actual incidence is unclear^[3]. However, the prevalence ranges from 2% to 6% per year^[4]. Usually, torsion takes place against the background of an ovarian mass or cyst^[5]. In the United States, abdominal pain accounts for almost 8% of all emergency room visits, making it one of the most frequent causes of emergency department visits^[6]. Acute appendicitis, cholecystitis, pancreatitis, and diverticulitis are among the common causes of an acute abdomen.^[7] A study was done in Nepal among 675 patients who had acute abdominal pain. The most frequent cause of acute abdomen, accounting for 52% of all admissions, was acute appendicitis^[6]. It is estimated that there is a 4.6% correlation between acute appendicitis and gynecological pathology^[8]. However, it is quite uncommon for acute adnexal torsion and acute appendicitis to occur simultaneously. Only a few cases of acute appendicitis concomitant with acute adnexal torsion have been reported^[1,2,8]. Here we present a case of a 39-year-old female who presented to the emergency department with complaints of right lower quadrant abdominal pain. It is very difficult to diagnose a case similar to this at first instance; it requires imaging for a diagnosis. So it is necessary to rule out not only surgical or medical causes of acute abdomen, rather it is necessary to rule out gynecological cases when a reproductive-age female presents to the emergency department with the complaint of acute abdomen. This work has been reported in line with the SCARE 2025 criteria^[9].

HIGHLIGHTS

• This case presents the rare simultaneous occurrence of acute appendicitis and ovarian torsion involving a dermoid cyst.

• The dual presentation made diagnosis more challenging, requiring imaging for accurate identification.

• Early diagnosis and surgical intervention were crucial to prevent complications like sepsis and gangrenous tissue.

• Computed tomography and ultrasonography were key in confirming the diagnosis.

• The patient underwent surgery, including appendectomy and right salpingo-oophorectomy, with positive recovery outcomes.

Case presentation

A previously healthy 39-year-old woman presented to the emergency department with a 5-day history of progressively worsening right lower quadrant abdominal pain that began acutely. The pain was non-radiating and unaffected by positional changes or meals. Associated symptoms included low-grade fever (maximum 101°F) for 1 day and three episodes of non-projectile, foul-smelling vomiting containing food particles. On examination, she appeared acutely ill with tachycardia (105 bpm), normal blood pressure (100/80 mmHg), and marked tenderness with a palpable mass in the right iliac fossa. Initial management with intravenous fluids, ceftriaxone, and ondansetron resulted in symptomatic improvement over 72 h, leading to discharge with a presumed diagnosis of appendicular lump. However, she re-presented 2 days later with recurrent severe abdominal pain. Diagnostic imaging revealed an ill-defined hypoechoic mass on ultrasonography (USG) followed by computed tomography (CT) findings of a large fat-containing cystic lesion with a twisted vascular pedicle consistent with ovarian torsion of a dermoid cyst with dilated, fluid-filled appendix marked with blue arrow with a luminal diameter of 7 mm, as shown in Figure 1A–C, along with incidental findings of left hepatic lobar hypoplasia as shown in Figure 2A, B with uterine enlargement. Given the complex cystic nature of the lesion and potential overlap with malignant ovarian pathology (e.g., immature teratoma or mucinous tumor), tumor markers (CA-125, LDH, and CEA) were obtained to assess malignancy risk. While CA-125 was moderately elevated (187 U/mL), likely reflecting inflammatory changes from torsion rather than epithelial ovarian cancer, and LDH (320 U/L) was nonspecifically increased due to tissue ischemia, the normal CEA helped exclude mucinous adenocarcinoma. These results, combined with imaging features favoring a benign dermoid cyst, supported proceeding with fertility-sparing surgery if feasible, although intraoperative findings of gangrenous changes necessitated bilateral salpingo-oophorectomy. However, the ROMA (Risk of Ovarian Malignancy Algorithm) was not calculated. Exploratory laparotomy confirmed a necrotic right ovarian mass with torsion and dense adhesions to both the appendix and adjacent bowel, along with hemorrhagic changes in the contralateral ovary. Gross examination revealed an appendix measuring 4 × 2 × 1 cm, as shown in Fig. 3C. The outer surface showed fibropurulent exudate with congested and dilated serosal blood vessels. In the cut section, the appendiceal lumen was obliterated by a fecolith. The right ovarian cyst measured 10 × 7 × 1 cm. Its outer surface was dark brown and glistening, with congested and dilated blood vessels as shown in Fig. 3D. The cut section revealed pultaceous material, consistent with a mature cystic teratoma. The fallopian tube measured 3 × 2 cm, with a dark brown outer surface. The cut section showed uniform hemorrhagic areas, suggestive of ischemic changes due to torsion. Histopathological examination of resected specimens confirmed acute appendicitis as shown in Fig. 3A and a benign mature cystic teratoma without malignant features as shown in Fig. 3B. The patient had an uncomplicated postoperative recovery and was discharged home on postoperative day 5 in stable condition. The patient was advised to return for follow-up in 2 weeks for reassessment of the tumor marker and postoperative evaluation. However, she was lost to follow-up, and subsequent results could not be obtained. Despite this limitation, the available clinical, surgical, and histopathological findings provide valuable insights into this rare co-occurrence of pathologies.

Figure 1.

(A) CT (computed tomography) of abdominal pelvis view showing large abdominopelvic cystic calcification (marked with black arrow and fat density (marked by white arrow). (B) Axial image in the venous phase shows that the cystic lesion is non-enhancing. (C) Sagittal image in the portal venous phase shows a dilated, fluid-filled appendix (marked with blue arrow) with a luminal diameter of 7.5 mm.

Figure 2.

Porto-venous phase coronal (A) and axial (B) views showing normal right lobe of liver, falciform ligament (marked by blue arrow), and hypoplasia of left lobe of liver.

Figure 3.

(A) Histopathological slide of acute appendicitis. (B) Histopathological slide of dermoid cyst. (C) Jar containing formalin mount appendix. (D) Gross specimen of dermoid cyst.

Discussion

Adnexal torsion happens when the ovary and fallopian tube rotate around the axis formed by the infundibulopelvic ligament and the utero-ovarian ligament. It typically affects both the ovary and the fallopian tube, although it can sometimes involve only the ovary, and more rarely, only the fallopian tube.^[3] Ovarian torsion typically occurs in the presence of an underlying ovarian condition, most often ovarian cysts or masses^[5]. Ovarian dermoid cysts are responsible for a significant portion of such cases^[8,10]. Ovarian dermoid cysts, also referred to as benign mature cystic teratomas, are fairly common neoplasms, accounting for up to 20% of benign ovarian tumors in young women^[11]. These cysts may be identified as incidental findings during a USG, either in women without symptoms or in those being evaluated for pelvic pain^[12]. Adnexal torsion involving dermoid cysts can lead to acute abdominal pain, requiring urgent surgery to untwist the ovary and remove the cyst. This is crucial to prevent ischemic damage to the ovary, particularly in adolescents and young women^[13]. As for our case, it was quite late to diagnose ovarian dermoid cyst torsion due to the co-occurrence with acute appendicitis. So at the time of diagnosis, the complication was already present. However, there is limited information on the relationship between adnexal torsion involving dermoid cysts and various demographic and surgical characteristics, with most recommendations being primarily based on expert opinion^[11]. The pathophysiology of dermoid cysts causing adnexal torsion is thought to be related to the fatty content of the cyst, which causes it to “float” outside the pelvis, potentially leading to torsion^[14]. Torsion typically occurs in women with moderately enlarged ovaries, often associated with an ovarian cyst. While it is more common in premenarchal girls, normal-appearing ovaries are involved in up to 46% of torsion cases^[15]. A study recently found a high prevalence of torsion at 22%, which may be linked to the younger population in our study, as well as the inclusion of premenarchal girls and adolescents, compared to previous studies^[11]. The size of the dermoid cyst has been suggested as a risk factor for torsion. The highest risk for torsion was believed to be associated with cysts of “intermediate” diameter (i.e., between 60 and 90 mm), while cysts with a diameter smaller than 50 mm were considered less likely to cause torsion. On the other hand, very large cysts with a diameter greater than 100 mm were also thought to be less likely to cause torsion, as their size would limit their movement within the pelvis^[13]. Torsion occurs more frequently on the right side than the left, with an incidence ratio of approximately 3:2. This is likely due to the left ovary’s proximity to the relatively fixed sigmoid colon, whereas the cecum and ileum on the right are more mobile^[16]. The key to making the diagnosis of adnexal torsion requires a detailed patient history and physical examination. Acute abdominal pain is the most typical symptom in women with adnexal torsion. Around 90–100% of the time, the beginning of abdominal pain is localized to one side^[17,18]. The pain can either be steady or intermittent, as the ovary may twist and untwist over time. It may start suddenly, often due to a change in position or activity. In a few cases, the pain can last from several days to months before someone seeks treatment, and there may be a history of similar brief pain episodes, suggesting past partial twisting of the ovary. The pain severity varies and is not always intense. It can be due to the blockage of blood flow, leading to a lack of oxygen. Typically, the veins and lymphatic system are affected first because they operate under lower pressure^[19]. Other symptoms are nausea (70%), vomiting (45%), pain in one localized abdominal side, and fever (20%). If the ovary remains twisted for too long, it can become damaged and infected, leading to signs of peritonitis. These symptoms are similar and can also be present in various other conditions, such as appendicitis, kidney stones, pelvic inflammatory disease, ectopic pregnancy, colitis, death of a fibroid tumor, and ruptured ovarian cysts, making it harder to diagnose the issue^[3]. Adnexal torsion is diagnosed based on clinical signs, and laboratory tests and imaging can help support the diagnosis. However, its symptoms are similar to those of several other conditions. Numerous studies have shown that diagnosing adnexal torsion before surgery is challenging, with laparoscopy confirming the diagnosis in only about 10–44% of cases^[3]. Pelvic ultrasound, with or without Doppler analysis, is the most frequently used imaging technique to help diagnose adnexal torsion. Ultrasound is a cost-effective, radiation-free imaging method that is widely accessible, although its accuracy depends on the skill of the operator. The transvaginal approach is typically preferred, but in pregnant, young, or virgin patients, a transabdominal approach can be used. However, this may make it harder to see the ovarian blood vessels clearly^[20]. But as for our case, due to confusion about symptoms, CT was advised. Adnexal torsion is a surgical emergency and requires immediate surgery. Treatment options for adnexal torsion include both conservative and definitive approaches. The choice of treatment depends on factors such as the patient’s age, future fertility plans, menopausal status, and any signs of ovarian disease. Conservative treatments involve untwisting the adnexa and confirming the tissue viability, removing any associated cysts, or both untwisting and aspirating the cyst. Among surgical approaches, most widely used is the laparoscopic approach. But if necrosis has already occurred, then definitive treatment is salpingectomy and/or oophorectomy^[3]. Although this patient underwent exploratory laparotomy due to concerns about gangrenous changes and dense adhesions seen on imaging, diagnostic laparoscopy could have been considered earlier in her clinical course for several reasons. Laparoscopy allows systematic evaluation of the entire abdominopelvic cavity, including contralateral ovary to rule out synchronous pathology, as seen in this case with the hemorrhagic left ovarian cyst; uterus and fallopian tubes to assess for concurrent pelvic inflammatory disease or endometriosis; appendiceal base to confirm/exclude appendicitis without requiring open surgery; and liver and peritoneal surfaces to detect incidental findings like hepatic hypoplasia earlier^[21].

Diagnostic Laparoscopy also has an advantage in stable patients with diagnostic uncertainty. This patient’s initial improvement with antibiotics suggested an inflammatory process, appendiceal mass vs. ovarian torsion. Laparoscopy could have differentiated these earlier by visualizing the appendix directly, avoiding CT radiation, and assessing ovarian viability with Doppler (if torsion was suspected). For ovarian masses, laparoscopy provides real-time assessment of cyst characteristics, for example, smooth walls favoring benign teratoma vs. excrescences suggesting malignancy. Exploratory laparotomy was ultimately required here due to a large cyst size with CT evidence of fat-fluid levels and calcifications, raising concern for mature cystic teratoma, but suspected gangrene and adhesions increased rupture risk during laparoscopic removal. Torsion duration (>72 h) and hemodynamic changes (tachycardia) favored open exploration for safer adhesiolysis and cyst resection^[22].

As a limitation of this case is, a single case report, our findings cannot be generalized. Additionally, the patient was lost to follow-up, limiting our ability to evaluate long-term outcomes or assess postoperative tumor markers. The proposed link between the dermoid cyst and appendicitis remains speculative and should be interpreted with caution. Although a twisted dermoid cyst is unlikely to directly cause appendicitis, the two conditions could occur at the same time, or one might indirectly affect the other because the right ovary and appendix are located near each other in the abdomen. The reason is that when a dermoid cyst twists, it can cause inflammation in the ovary and nearby tissues. This inflammation could spread to nearby organs, such as the appendix, potentially leading to irritation or infection, which may raise the risk of appendicitis. However, this type of secondary inflammation is uncommon or a large right-sided dermoid cyst giving pressure on the appendix, resulting in irritation and inflammation of the appendix, which is more like an indirect effect of the dermoid cyst. The exact mechanism of co-occurrence is still unknown, and hence these are speculative associations. In our case, the presence of a fecolith within the appendiceal lumen suggests a more traditional etiology for appendicitis. While the simultaneous presentation may be coincidental, the overlapping anatomical and inflammatory factors warrant further exploration in future studies. Similar cases have been documented in the literature, although few have reported such co-occurrence with initial presentation as an appendicular lump. The exact mechanism behind hepatic hypoplasia is unclear, but it is believed to result from disrupted portal flow due to thrombosis. Typically asymptomatic, liver hypoplasia does not impact the patient’s health and is often discovered incidentally during imaging studies.^[23]

This case represents an exceptionally rare clinical entity, with only a handful of documented cases worldwide. While reviewing the existing literature, we identified several reports with similar presentations and management approaches. However, this case appears to be unique as it represents the first reported instance where an appendicular lump coexisted with the primary pathology, adding a novel dimension to the existing clinical understanding of this condition^[8,24,25].

Conclusion

This case emphasizes the rarity of the simultaneous occurrence of acute appendicitis and ovarian torsion involving a dermoid cyst, which can present as a diagnostic challenge. A twisted dermoid cyst may not directly cause appendicitis. However, their anatomical proximity may contribute to concurrent inflammation of the ovary and appendix, which might lead to secondary inflammation or irritation of the appendix, potentially complicating the clinical picture. While fecolith presence suggests an obstructive cause, the possibility of torsion-related inflammatory or compressive influence on the appendix cannot be ruled out. The coexistence may represent either a coincidental or multifactorial event. Therefore, conclusions must be drawn cautiously. Early diagnosis and intervention are crucial, as these conditions can result in serious complications like gangrenous tissue and sepsis if left untreated. This case underscores the importance of considering both gynecological and surgical causes in women presenting with acute abdominal pain, particularly when both ovarian torsion and appendicitis may be present. Accurate imaging, including CT or USG, plays a key role in confirming the diagnosis and guiding treatment, which in this case involved surgical management of both the appendix and the affected ovary.

Ethical approval

Ethical approval was not required for this case report in accordance with local and national guidelines.

Consent

Written informed consent was obtained from the patient’s parents for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Sources of funding

No funding or grant support was received.

Author contributions

All authors attest that they meet the current ICMJE criteria for authorship. S.B.: project administration, resources, writing – original draft, and writing – review and editing. S.K.: project administration, resources, writing – original draft, and writing – review and editing. S.D.: writing – original draft and writing – review and editing. S.P.: resources and writing – review and editing. M.K.: resources and writing – review and editing. A.P.: project administration, Resources, Conceptualization, writing orignal draft, writing and review and editing.

Conflicts of interest disclosure

The authors have no conflicts of interest to declare.

Research registration unique identifying number (UIN)

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Guarantor

Anish Paudyal.

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Not applicable.

Data availability statement

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