One of such acute surgical emergencies is acute appendicitis and its incidence is 7-10 per 10,000 population[1]. Although the majority of the cases have the typical right lower quadrant and systemic evidence of inflammation, the clinical manifestation is subject to considerable change, especially in the special groups, including pregnant women and the reproductive age group[2]. The presence of positive pregnancy test, high β-hCG, and right-sided pelvic mass in women at full reproductive age with acute abdominal pain leaves a high uncertainty of diagnosis[3]. A combination of clinical presentation and radiographics frequently gives the idea of ruptured ectopic pregnancy and the latter would be an obstetrical emergency that could prove fatal unless surgical care is provided at the earliest possible moment[4]. It is estimated that ectopic pregnancy occurs in 1-2 percent of pregnancies, and this disease is a major cause of maternal deaths in the first trimester, causing 5-10 percent of maternal deaths in developed countries[5]. Nonetheless, the location of the appendix to left-sided adnexal structures (fallopian tube and ovary) gives rise to the possibility of diagnostic confusion because appendiceal pathology may mimic an adnexal mass on physical examination and radiology[6]. Perforated appendicitis has a high morbidity and mortality rate of 5-30 per cent based on the age of the patient, comorbid conditions, and the duration of intervention[7]. Mortality rate is high with delay in surgical care especially when the perforation has already taken place [8]. Thus, fast and proper diagnosis is paramount. We provide the case of a young female who reported to the clinic with clinical and radiological features strongly indicating ruptured ectopic pregnancy but it was later confirmed that the patient had perforated appendicitis with suppurative peritonitis on exploration surgery. The case demonstrates the diagnostic difficulty in the distinction of these two acute surgical crises and highlights the necessity of having a wide differentiation diagnosis in women of reproductive age that presented with acute pain in the pelvis and positive pregnancy status [9].

Demographics and Presentation of Patient. An emergency case with a female reproductive age patient reported with severe acute left lower quadrant pain, of acute onset. The patient has complained of the development of pain that is related to nausea and malaise. Physical assessment showed that the patient had much right lower quadrant tenderness and guarding, with rebound tenderness, which is a symptom of peritonitis. The home pregnancy test was reported positive. Lab tests showed high levels of 2hcg with indications of early pregnancy or any other pathology that causes the level of hcg to increase. The levels of white blood cells were high, which is in keeping with the acute inflammatory process. Pregnancy test on urine was also positive. Imaging Findings The positive status of pregnancy and the fear of ectopic pregnancy led to the conduct of pelvic ultrasound. Imaging revealed: • Heterogeneous, complex left-sided adnexal mass. Dimensions of mass that were found to be important. • Mass was observed to be different with the left ovary. • The complex mass does not contain any clear gestational sac, yolk sac or fetal pole. • Free fluid was observed in the ultrasound. • Endometrial findings of possible structure of early intrauterine pregnancy or other intrauterine pathology. The radiological impression was very much concerned with ruptured ectopic pregnancy due to the occurrence of positive pregnancy test, high 8hcg, complex adnexal mass on the left, and clinical presentation with acute pain in the abdomen. Clinical Decision-Making Considering the clinical suspicion of ruptured ectopic pregnancy and the acute appearance of the patient with the symptoms of peritonitis, the emergency surgical exploration was the suitable option. The patient was advised about the fact of the Exploratory laparotomy with possible development into the salpingectomy/salpingostomy had informed consent given in the case of confirmation of ectopic pregnancy. Operative Findings Exploratory laparotomywas carried out under spinal anesthesia. The first pelvic examination showed: • Bilateral ovaries: patients have normal size, appearance and location. • Fallopian tubes: Patent bilaterally, unremarkable. Uterus: of normal size and structure, no apparent abnormality. Free fluid: Pelvic purulent/suppurative peritoneal fluid. Appendix: Significantly thick, indurated, and hyperemic as is characteristic of acute inflammation. Appendicitis, purulent exudate, perforation of the appendix. • Peritoneal contamination: Fibrinous suppurative peritonitis. The results of intraoperative observation were evidently perforated appendicitis and not the gynecological pathology. The purulent peritoneal fluid and inflamed and perforated appendix were the reasons behind the high levels of inflammatory markers and the appearance of the complicated right-sided mass during imaging. Surgical Intervention appendectomy was done in the usual manner: Determination and mobilization of the perforated appendix. Cutting of vessels of the appendix at the base with either harmonic scalpel or vessel sealing device. Sectioning of mesoappendix to liberate the appendix of attachments. Silencing or sealing the appendiceal stump. A trocar point was used to extract the specimen to safely prevent spillage of eright fluid. Peritoneal lavage and lavage purulent material with large volumes of normal saline and fibrinous debris. Confirmation of hemostasis, and checking of any other pathology. The working time was about 45 minutes. Blood loss was minimal. The patient was also well tolerant to the procedure with no intraoperative complications reported. Pathological Findings The removed specimen of the appendix presented: • Acute inflammatory suppurative inflammation of the appendix wall. • Bacterial contamination indicated with evidence of perforation. • There is acute inflammatory infiltrate in every layer of the appendix. • None of neoplasia or other chronic pathology. Final histopathology revealed acute perforated appendicitis and suppurative peritonitis. Postoperative Course The postoperative plan of the patient was, in general, not complicated: • Pain management: Sufficient with conventional analgesics. • Antibiotic treatment: Recurring relevant extensive-spectrum antibiotics addressing enteric organisms. • Oral intake: Gradual increase as well as possible. • Ambulation: Early move promoted. Discharge: Patient was discharged on postoperative day 10 and proper follow-up was to be made. The high level of β-hCG was later to be eliminated after appendectomy and this confirmed that the high level was probably as a result of the acute inflammatory process and not pregnancy. When the patient was examined in follow-up, she stated that the symptoms had disappeared entirely and the abdominal pain was no longer experienced.

Diagnostic Considerations This case demonstrates one of the important diagnostic dilemmas that might be met in the emergency department or the gynecological practice. In the reproductive-aged female presenting with acute pelvic pain, positive pregnancy test, high β -hcg with an imaging appearance of a left-sided adnexal mass, the clinical suspicion is that of ectopic pregnancy[10]. Nevertheless, as it is revealed in this case, there are a number of non-gynecological pathologies that may have an identical or very similar clinical presentation: Acute Appendicitis and Perforated Appendicitis. The most prevalent acute surgical of all emergencies is that of acute appendicitis which happens at a rate of around 7-10 cases per 10,000 population[1]. The typical manifestation consists of right lower quadrant pain, anorexia, nausea, vomiting and fever. The normal physical findings include rebound tenderness, guarding, and positive Rovsing sign[11]. In perforated appendicitis, the clinical picture is more acute, which is accompanied by more sharp pain, more clear peritoneal manifestations and increased risk of systemic manifestations such as fever and sepsis[12]. Inflammation of perforation and peritoneal contamination may lead to complicated inflammatory mass that resembles an adnexal mass on the image[13]. The increase in the number of white blood cells that is accompanied by left shift is characteristic of acute appendicitis, but may also be related to ectopic pregnancy, especially when the rupture has already taken place, and inflammatory process has been initiated. Thus, the laboratory results cannot be used to determine the difference between these diagnoses[14]. Imaging Limitations The conventional imaging used to assess pelvic pain in reproductive aged women is ultrasound because it is easily available, it does not expose them to radiation, and the ultrasound has a good resolution of gynecological structures[15]. Nevertheless, ultrasound is of limited use in the examination of the gastrointestinal tract and may falsely define inflammatory masses of the appendix as adnexal pathology[16]. In the case, the left-sided complex mass observed in ultrasound was suspected to be ectopic pregnancy according to: • Location next to the left ovary. • Complex intralobar echogenicity. • Absence of typical ultrasound appearance of normal pregnancy (yolk sac, fetal pole) free fluid. Nevertheless, a number of characteristics ought to have been cause to suspicion appendiceal origin: Mass independent of and different to the ovary. • Peripheral blood flow deficiency associated with ectopic pregnancy. • Gestational sac and products of conception not observed. • Charismatic inflammatory imaging. Role of Advanced Imaging Computed tomography (CT) scan and magnetic resonance imaging (MRI) have better capability to identify the difference between the gynecological structures of the pelvis and the gastrointestinal pathology[17]. The CT findings of acute appendicitis normally show: • Appendiceal wall thickened (> 2 mm ) • Distention of the appendix (>6 mm diameter) • Stranding of peri appendiceal fat. • Collection of perforated cases peri appendiceal fluid. • Appendiceal wall improvement using intravenous contrast. MRI is well resolved in terms of soft tissue contrast and is able to differentiate between the structures of the ovarian/fallopian tube and appendiceal pathology. Besides, MRI is safe to apply during the early stages of pregnancy where CT would expose the unborn baby to ionizing radiations[18]. Clinical guidelines point out that, in case of the equivocal ultrasound findings in a patient presenting with acute pelvic pain and positive pregnancy status, CT or MRI is recommended to further define the diagnosis[19]. Laboratory Investigation Although the positive β-hCG test was assumed to be a sign of pregnancy, the increase in this instance was probably caused by inflammatory process (in acute form) or malignancy (in case it existed) as opposed to actual intrauterine or ectopic pregnancy. This shows the importance of: Serial β-hCG values with reasonable levels of doubling or falling. • Association with ultrasound results. • Other conditions that can increase β-hCG (molar pregnancy, choriocarcinoma, germ cell tumors, and in rare cases appendiceal adenocarcinoma) should be taken into account. Differential Diagnosis Review. In the case of a reproductive-aged female with acute pelvic pain and positive β-hCG, the following should be listed as the differential diagnosis: Ectopic pregnancy (tubal, ovarian, interstitial, abdominal) - The most frequent diagnosis that should be ruled out. Perforated appendicitis - As it is seen in this case. Acute appendicitis (non-perforated) - May manifest in the same way with less peritonitis. Ovarian torsion - The condition is painful, and the inflammatory markers can be elevated. Ruptured ovary cyst - As a rule, self-limiting, but acute pain. Tubo- ovarian abscess- May include fever, high levels of inflammatory markers. Pelvic inflammatory disease - Subacute presentation is normal but acute exacerbations may take place. Diverticulitis- Left-sided, may be right-sided. Ureterolithiasis - Pain on the right, however, the patient may not show peritoneal findings. Inflammatory bowel disease - May be acutely aggravated. Mesenteric adenitis Viral prodrome common, can resemble appendicitis. Acute peritoneal symptoms (rebound, guarding) and unequivocal intraperitoneal fluid is extremely indicative of surgical anatomy that needs an urgent operation[20]. Clinical Bias and Diagnostic Anchoring. Another phenomenon of medical diagnosis that is present in this case is diagnostic anchoring or anchoring bias[21]. The patient had a positive test of her pregnancy and high levels of β-hCG and this background of the patient affected interpretation of radiological studies to which radiologist and clinician were predetermined to the diagnosis of the ectopic pregnancy. The outcome of this cognitive bias may be: • Excessive interpretation of imaging results in favor of the anchored diagnosis. • Lack of use of other diagnostic modalities that could help get a clear picture of the diagnosis. • Latitude in alternative diagnosis. To reduce diagnostic bias: Repeatedly, radiologists should review imaging blind to clinical history. • The pursuance of alternative imaging modalities should be done when results are inconclusive. Repeatedly, there must be a differential diagnosis maintained in the face of clinical suspicion of one diagnosis. The success of preoperative diagnostic impressions[22] should be established or disproved by intraoperative findings. Treatment of Perforated Appendicitis. Perforated appendicitis is an urgent surgical procedure because it requires: • Debridement of the cause of peritoneal contamination (perforated appendix) • Peritoneal infection control by lavage and source control. • Stop the development of sepsis and multi organ failure. Exploratory laparotomy was done under SA Severe peritonitis eliminates proper visualization. • Laparoscopically, it is not possible to control bleeding. • Large fibrils do not allow dissection to be done safely. • Dissection involves associated injuries. It is important that the peritoneal lavage be done using copious normal saline (3-5 liters) to eliminate bacterial contamination and fibrinous debris. It is required to close the visceral perforation and remove the inflamed appendix in order to curb the cause of infection.

Elevated β-hCG in Non-Pregnancy. The positive β-hCG in this scenario provides a reason to discuss other conditions besides pregnancy that result in the presence of hCG: Molar pregnancy - This is defined by the extreme elevation of β-hCG with ultrasound appearance of snow storm appearance[23]. Gestational trophoblastic disease - Relates to molar pregnancy. Germ cell tumors - Testicular, ovarian, mediastinal (trust, especially choriocarcinoma, embryonal carcinoma) Adenocarcinomas - Infrequently gastric, lung, colon may secrete hCG. Lymphomas - Not common but reported. Acute inflammatory conditions - There are a few reports of small hCG increase in severe infections[24]. The fact that the elevated β-hCG was resolved after appendectomy is an affirmation that the increase was as a result of the appendiceal pathology and not actual pregnancy or malignancy. TEACHING POINTS A number of significant clinical lessons can be drawn in this case: Broader Differential Diagnosis: Have a broad differential diagnosis even when one of the diagnoses (ectopic pregnancy) appears most probable based on initial presentation. Imaging Limitations: Learn the limitations of each imaging modality (ultrasound in the case) and seek out more powerful imaging (CT, MRI) when the initial results are ambiguous. Signs of Peritoneal Instructions: When the rebound tenderness and guarding is present, it indicates peritonitis that requires urgent exploration and this is more threatening in perforated viscus than mere ectopic pregnancy. Anatomical Proximity: The location of the fallopian tube and ovary, right-sided pelvic structures, are close to the appendix, resulting in possible confusion of appendiceal pathology with gynecological pathology. Cognitive Bias: Be aware of the diagnostic anchoring and bias when clinical details tend to be very strong to make a specific diagnosis; be active to get information that questions the diagnosis that has been anchored but not to verify the diagnosis in which the anchored information is. Serial Laboratory Values: Individual high β-hCG or inflammatory items are not diagnostic, serial values with the correct trends are more informative. Intraoperative Confirmation: When there is uncertainty in the diagnosis, surgical exploration can be done to give definite diagnosis and to treat it accordingly.

Perforated appendicitis may have clinical and radiographic manifestations that are very similar to the ruptured ectopic pregnancy in women of reproductive age. The positive pregnancy test plus increased 8-hCG on top of the right lower quadrant pain and visualization of a right-sided pelvic mass causes confusion in diagnosis. Prudent clinical evaluation with consideration of peritoneal manifestations, proper use of high-tech imaging techniques in case of uncertainness of initial ultrasound, and a wide differential diagnosis are crucial in proper diagnosis. In cases of diagnostic doubt, even after the proper investigations, emergency surgical exploration is the treatment of choice to give a definite diagnosis and treatment intervention. The anatomical closeness of the appendix to left-sided adnexal structures would make appendiceal pathology to be included in the list of possible diagnostic issues of the patients with right lower quadrant pain and positive pregnancy status. There should also be a high index of suspicion regarding acute abdominal pathology of non-gynecological etiology, especially when the result of the imaging procedure fails to provide a clear picture of the gynecological pathology.

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