Archives of Academic Emergency Medicine. 2019; 7 (1): e44 OR I G I N A L RE S E A RC H One-Month Follow-Up of Patients with Unspecified Ab- dominal Pain Referring to the Emergency Department; a Cohort Study Seyed Mohammad Hoseininejad1, Reza Jahed2, Mohammad Sazgar3, Fatemeh Jahanian3, Seyed Jaber Mousavi4, Seyed Hosein Montazer3, Touraj Assadi3, Hamed Aminiahidashti3∗ 1. Gut and Liver Research Center, Mazandaran University of Medical Sciences, Sari, Iran. 2. Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran. 3. Emergency Department, Mazandaran University of Medical Sciences, Sari, Iran. 4. Department of Community Medicine, Mazandaran University of Medical Sciences, Sari, Iran. Received: June 2019; Accepted: July 2019; Published online: 17 August 2019 Abstract: Introduction: About one third of patients referring to emergency department (ED) with abdominal pain, are discharged without a definite diagnosis. This study aimed to investigate the one-month outcome of patients with unspecified abdominal pain. Methods: This cohort study was conducted on subjects who were evaluated in ED with unspecified abdominal pain and were referred to the gastroenterology clinic and followed for one month. Finally, they were divided into two groups of cases with clear cause of abdominal pain and unclear cause of abdominal pain and patients’ characteristics were compared between the groups. Results: 150 cases with the mean age of 40.68 ± 18.34 years were studied (53.3% female). After one month, 67 (44.7%) patients still complained of abdominal pain. A definitive cause of abdominal pain was established in 88 (58.7%) cases. There was not any significant difference between groups regarding, sex distribution (p = 012), duration of pain (p = 0.11), history of previous similar pain (p = 0.136), pain radiation (p = 0.737), length of hospital stay (p = 0.51), and presence of anorexia (p = 0.09), nausea and vomiting (p= 0.50), fever (p = 1.0), diarrhea (p = 0.23), and constipation (p = 0.07). There was a significant difference between the groups regarding location of pain (p = 0.017), age (p = 0.001) and history of comorbid diseases (p = 0.046). The predictive factors of finding a clear cause for abdominal pain in one-month follow-up, were leukocytosis (OR: 5.92 (95% CI: 2.62 – 13.39); p < 0.001), age (OR: 2.78 (95% CI: 1.15 – 6.71); p = 0.023), and outpatient follow-up (OR: 1.04 (95% CI: 1.02 – 1.07); p < 0.001). Conclusion: Approximately, 40% of patients who were discharged with unspecified abdominal pain did not receive a clear diagnosis after one month of follow-up. Older age, leucocytosis in initial evaluations, and outpatient follow-up increased the probability of finding a clear cause for abdominal pain in the mentioned cases. Keywords: Abdominal pain; patient discharge; follow-up studies; emergency service, hospital Cite this article as: Hoseininejad S M, Jahed R, Sazgar M, Jahanian F, Mousavi S J, Montazer S H, Assadi T, Aminiahidashti H. One-Month Follow-Up of Patients with Unspecified Abdominal Pain Referring to the Emergency Department; a Cohort Study. Arch Acad Emerg Med. 2019; 7(1): e44. 1. Introduction Acute abdominal pain is defined as a non-traumatic pain that has begun less than 5 days before (1). It is one of the ∗Corresponding Author: Hamed Aminiahidashti; Imam Khomeini Hos- pital, Amirmazandarani Boulevard, Sari, Iran. Email: hamedaminiahi- dashti@yahoo.com Tel: +98 9113540546 most common clinical complaints of patients that refer to the emergency department (ED) and is the cause of about 7-10% of all ED referrals (2, 3). Despite the high frequency of these referrals to the ED, there is no definitive diagnostic way to distinguish between emergency and non-emergency causes for abdominal pain (1). 28% to 36% of these patients are discharged without definite diagnosis (4-6). The unclear cause of abdominal pain in the ED is commonly associated with insufficient history taking, inadequate use of diagnos- This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem S M. Hoseininejad et al. 2 tic tests, and problems related to follow-up visit and test re- sults (7). This challenge in differential diagnosis of abdom- inal pain can result in adverse consequences and legal and medical lawsuits (8). Although thorough physical examina- tion, careful observation, and repeated diagnostic tests are effective ways to reduce the risk of harmful and unintended consequences (9), in many cases, patients are dissatisfied with the long waiting time in ED (10). In addition, there is no specific guideline for dealing with patients with abdom- inal pain without definite diagnosis in ED (11). Based on above-mentioned points, this study aimed to investigate the one-month outcome of patients with abdominal pain with- out definite diagnosis in ED. 2. Methods 2.1. Study design and setting This cohort study was conducted in Gastroenterology Re- search Center, Imam Khomeini Hospital, Mazandaran Uni- versity of Medical Sciences, Sari, Iran from March 2016 to February 2017. Imam Khomeini Educational Hospital is a public and tertiary referral center in Mazandaran province with 400 beds, and the Gastroenterology Center is one of the first research centers in this area. This study was con- ducted on subjects who were admitted to the ED with ab- dominal pain with ICD 10 code R10.4. All patients with ab- dominal pain (ICD10 code R10) were visited by an emergency medicine specialist and they were admitted to the observa- tion unit of ED for at least 6 hours and the serious causes of abdominal pain were ruled out. Patients with abdominal pain who were diagnosed at this stage were excluded. Pa- tients with unclear diagnosis were referred to the gastroen- terology clinic and followed for one month. Finally, patients were divided into two groups of patients with clear cause of abdominal pain and unclear cause of abdominal pain af- ter one-month follow-up and patients’ characteristics were compared between groups. All information of the participants was confidential and they were enrolled into the study after obtaining the consent of the patient or their relatives. This study was approved by the Ethics Committee of Mazandaran University of Medical Sci- ences with the reference code: IR.MAZUMS.REC.95-1625. 2.2. Participants All patients with non-traumatic abdominal pain who were discharged without a definite diagnosis despite physical ex- amination, laboratory, and imaging studies (ICD 10 code R10.4) were included in the study. Addicts or those with a his- tory of addiction, pregnant women, patients with abdominal pain following trauma, those who left the ED against medical advice, and those who were lost to follow-up after a month, were excluded. In addition, patients who were under obser- vation for 6 hours and a definite cause was diagnosed and those whose clinical condition was not suitable for discharge and were admitted to ward according to the decision of the emergency medicine specialist were excluded. 2.3. Patients’ Follow-up A summary of the patient’s ED clinical profile was given to each patient and referred to the gastroenterology clinic. Ev- ery week the patients’ data were collected from the gastroen- terology clinic and they were contacted via phone after a month. In addition, a visit was arranged with the patient or their relatives, and the completed investigation, definitive di- agnosis, recovery, mortality and morbidity were questioned and recorded. 2.4. Data Gathering Definitive diagnosis, age, sex, duration of pain, severity and location of pain, duration of admission, underlying disease, accompanying signs and symptoms, laboratory findings, as well as the results of one-month follow-up regarding read- mission, pain status, cause of pain, and mortality were col- lected using a predesigned checklist. Data from each of the groups were collected by the main author without any inter- vention in the patient’s treatment and care process. 2.5. Statistical Analysis All data were collected and recorded in SPSS statistical soft- ware version 22.0. Quantitative data were described as mean ± standard deviation. Frequency and percentage of variables were used to describe qualitative data. Chi square (X2) test and logistic regression analysis were used to determine the associated factors of the probability to reach a definite diag- nosis. P value less than 0.05 was considered statistically sig- nificant. 3. Results 3.1. Baseline characteristics of studied patients 39,817 patients were admitted to the emergency department during the study period (4162 cases was classified as ICD10 code R10). Only 328 (7.77%) patients were eligible for enroll- ment to the study (ICD10 code R10.4) and, finally, a study was conducted on 150 patients (Figure 1). The subjects’ mean age was 40.68 ± 18.34 (6-85) years (53.3% female). In a re-visit to gastroenterology clinic after one month, 83 (55.3%) patients noted their pain was relieved, and 67 (44.7%) patients still complained of their pain. Meanwhile, 63 (42%) patients com- plained of multiple referrals due to abdominal pain. A defini- tive cause of abdominal pain was established in 88 (58.7%) cases, yet the cause of abdominal pain was still unclear in 62 (41.3%) patients. Most patients were diagnosed with re- nal colic (16.6%), followed by biliary colic (8.7%) and ovarian This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 3 Archives of Academic Emergency Medicine. 2019; 7 (1): e44 Figure 1: Patient selection flowchart. cyst (5.3%). 3.2. Comparing the groups Table 1 and figure 2 compare the baseline characteristics of patients with clear and unclear causes of abdominal pain. There was not any significant difference between patients with clear and unclear cause of abdominal pain regarding, sex distribution (p = 012), duration of pain ( p = 0.11), history of previous similar pain (p = 0.136), pain radiation (p = 0.737), length of hospital stay (p = 0.51), and presence of anorexia ( p = 0.09), nausea and vomiting (p= 0.50), fever (p = 1.0), diar- rhea (p = 0.23), and constipation (p = 0.07). Patients with clear cause of abdominal pain were older than those with unclear cause (p = 0.001). There was a significant difference between groups regarding the location of pain at the time of presenting to ED (p = 0.017) and history of comor- bid disease (p = 0.046). Although the frequency of leukocyto- sis (WBC > 11,000) was not significantly different between the two groups, mean WBC count on the first day of admission was significantly higher in patients with clear cause (10.5 ± 3.40 versus 9.4 ± 3.17 × 103/µL; p = 0.043). Table 2 compares the one-month outcomes of cases with clear and unclear cause of abdominal pain. Based on lo- gistic regression analysis, the predictive factors of finding a clear cause for abdominal pain in one-month follow-up were leukocytosis (OR: 5.92 (95% CI: 2.62 – 13.39); p < 0.001), age (OR: 2.78 (95% CI: 1.15 – 6.71); p = 0.023), and outpatient follow-up (OR: 1.04 (95% CI: 1.02 – 1.07); p < 0.001). 4. Discussion In this study, it was found that approximately 40% of patients who were discharged with abdominal pain without a definite diagnosis did not receive a final definitive diagnosis or clear cause. The most common definite diagnosis in this study was kidney stones. Older age, leucocytosis in initial evaluations, and outpatient follow-up increased the probability of finding a clear cause for abdominal pain in the mentioned patients. In some studies, appendicitis (12) and gastric ulcers (13) were reported as the most common causes of abdominal pain without definite diagnosis. In our study, the pain associ- ated with renal stones (renal colic) was the most common cause of abdominal pain, which was similar to the findings of Cervellin et al. (6). It was previously shown that older age is associated with increased hospitalization length and definitive diagnosis (14), which is consistent with the results of our study. In addition, increased likelihood of problems such as mesenteric ischemia, and rupture of aortic aneurysm in cases with underlying diseases such as diabetes and hyper- tension, makes further workups necessary in these groups of subjects (15, 16). Although in some studies there was no sig- nificant relationship between leukocyte count and definitive diagnosis of abdominal pain (13), in our study the increase in white blood cells had a significant relationship with finding a definitive cause for abdominal pain. In the study of Cervellin, 6.9% of patients with abdominal pain returned to the emer- gency department within the first 5 days, and 7.6% of the pa- tients returned within 5 days to one month after discharge. In the second visit, the initial diagnosis was changed to renal colic in many of these patients (6). In the present study 150 patients were discharged, 87 of whom were readmitted to emergency department and 67(44.67%) had definite diagnosis in readmission. In a study, it was shown that pain in the right lower quadrant of the ab- domen is likely associated with definitive diagnosis and led to surgery, especially in older people (17). Patients with abdominal pain who are discharged without a definite diagnosis are recommended to refer to a medical center if abdominal pain continues for 2 consecutive days (18). In our study, abdominal pain patients discharged with- out a definite diagnosis who were re-visited in the gastroen- terology clinic were more likely to receive a definite diagno- sis. This demonstrates the importance of follow-up. If there is suspicion of patients’ inability to follow up, they should remain in the ED under observation and the emergency de- partment should provide the needed facilities. Patients with abdominal pain discharged without a definite diagnosis should be carefully evaluated. Patients with older age, readmission, and leukocytosis may be at risk for pres- ence of a clear cause for abdominal pain. So they may bene- fit from longer observation and consultation for hospitaliza- This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem S M. Hoseininejad et al. 4 Figure 2: Location of pain in cases with clear and unclear cause of abdominal pain (p = 0.017). RLQ: right lower quadrant of abdomen, LLQ: left lower quadrant of abdomen, RUQ: right upper quadrant of abdomen, LUQ: left upper quadrant of abdomen. Table 1: Comparing the baseline characteristics of patients with clear and unclear cause of abdominal pain Variable Cause of abdominal pain P value Clear (n = 88) Unclear (n = 62) Age (years) Mean ± SD 44.9 (18.7) 34.5 (15.9) 0.001 Gender Male 45 (51.1) 25 (40.3) 0.12 Female 43(48.9) 37(59.7) Duration of pain before admission (hours) Mean ± SD 35.1(47.5) 58.7(128.1) 0.11 History of similar pain Yes 17 (70.8) 7 (29.2) 0.136 No 71 (56.3) 55 (43.7) Length of hospital stay (days) Mean ± SD 6.7 (4.4) 6.1 (5.1) 0.51 History of comorbidity1 Yes 48 (54.5) 23 (37.1) 0.046 No 40 (50.6) 39 (49.4) Pain radiation Yes 6 (66.7) 3 (33.3) 0.737 No 82 (58.2) 59 (41.8) Presenting sign and symptom Anorexia 13 (14.8) 16 (25.8) 0.09 Nausea and vomiting 51(58.0) 32 (51.6) 0.50 Fever 7 (8.0) 5 (8.1) 1.0 Diarrhea 5 (5.7) 7 (11.3) 0.23 Constipation 5 (5.7) 9 (14.5) 0.08 Laboratory findings Leukocytosis2 33 (40.7) 15 (25.9) 0.07 Anemia3 32 (39.5) 25 (43.1) 0.32 Data are presented as mean ± standard deviation (SD) or number (%). 1: diabetes mellitus, hypertension, renal stone, menorrhagia, ovarian cyst, discopathy, GI bleeding, end stage renal disease, and etc., 2: White blood cell count ≥11×103 /µL, 3: Hemoglobin<10 mg/dl. tion. In case of discharge, patients with abdominal pain who are discharged without a definite diagnosis should be moni- tored by family physicians and/or as an outpatient referring again after a specific interval with specific instructions at the time of discharge. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 5 Archives of Academic Emergency Medicine. 2019; 7 (1): e44 Table 2: Comparing the one-month outcomes of cases with clear and unclear cause of abdominal pain Variables Cause of abdominal pain P value Clear (n = 88) Unclear (n = 62) Pain condition Painless 55 (62.5) 48 (77.4) 0.07 Painful 33 (37.5) 14 (22.6) Readmission Yes 27 (35.5) 40 (64.5) <0.001 No 61 (69.3) 22 (35.5) Mortality Yes 7 (8.0) 2 (3.2) 0.308 No 81 (42.6) 60 (57.4) Data are presented as number (%). 5. Limitation There were several limitations in this study. Many of the pa- tients who enrolled did not fully cooperate or provided in- correct information on their diagnostic and therapeutic pro- cedures. Patients’ medical records were incomplete in some cases, which caused a limitation in the number of samples. 6. Conclusion Approximately 40% of patients who were discharged with ab- dominal pain without definite cause did not receive a clear diagnosis. Older age, leucocytosis in initial evaluations, and outpatient follow-up increased the probability of finding a clear cause for abdominal pain in the mentioned patients. 7. Appendix 7.1. Acknowledgements This research is based on the thesis of Dr. Reza Jahed, who graduated from Mazandaran University of Medical Sciences. We sincerely thank staff of the Emergency Department, gastroenterology clinic and medical records department of Imam Khomeini Hospital, Sari, Mazandaran province, Iran. 7.2. Author contribution All authors met the standard criteria of authorship based on the recommendations of the international committee of medical journal editors. Authors ORCIDs Seyed Mohammad Hoseininejad: 0000-0002-1713-5791 Mohammad Sazgar: 0000-0001-7497-3364 Fatemeh Jahanian: 0000-0002-5961-6315 Seyed Jaber Mousavi: 0000-0002-9623-2708 Seyed Hosein Montazer: 0000-0002-9785-586X Touraj Assadi: 0000-0003-2336-6470 Hamed Aminiahidashti: 0000-0002-2115-1903 7.3. Funding/Support None. 7.4. Conflict of interest There are no conflicts of interest. References 1. Gans SL, Pols MA, Stoker J, Boermeester MA, expert steering g. Guideline for the diagnostic pathway in pa- tients with acute abdominal pain. Digestive surgery. 2015;32(1):23-31. 2. Hastings RS, Powers RD. Abdominal pain in the ED: a 35 year retrospective. The American journal of emergency medicine. 2011;29(7):711-6. 3. Niska R, Bhuiya F, Xu J. National Hospital Ambulatory Medical Care Survey: 2007 emergency department sum- mary. National health statistics reports. 2010(26):1-31. 4. Cooper JG, Hammond-Jones D, O’Neill E, Patel R, Mur- phy R, Clamp SE, et al. The Clinical Decision Unit has a role to play in the management of acute undifferen- tiated abdominal pain. European journal of emergency medicine : official journal of the European Society for Emergency Medicine. 2012;19(5):323-8. 5. Caporale N, Morselli-Labate AM, Nardi E, Cogliandro R, Cavazza M, Stanghellini V. Acute abdominal pain in the emergency department of a university hospi- tal in Italy. United European gastroenterology journal. 2016;4(2):297-304. 6. Cervellin G, Mora R, Ticinesi A, Meschi T, Comelli I, Catena F, et al. Epidemiology and outcomes of acute ab- dominal pain in a large urban Emergency Department: retrospective analysis of 5,340 cases. Annals of transla- tional medicine. 2016;4(19):362. 7. Medford-Davis L, Park E, Shlamovitz G, Suliburk J, Meyer AN, Singh H. Diagnostic errors related to acute ab- dominal pain in the emergency department. Emergency This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem S M. Hoseininejad et al. 6 medicine journal : EMJ. 2016;33(4):253-9. 8. Kachalia A, Gandhi TK, Puopolo AL, Yoon C, Thomas EJ, Griffey R, et al. Missed and delayed diagnoses in the emergency department: a study of closed malprac- tice claims from 4 liability insurers. Annals of emergency medicine. 2007;49(2):196-205. 9. Agresta F, Ansaloni L, Catena F, Verza LA, Prando D. Acute appendicitis: position paper, WSES, 2013. World journal of emergency surgery : WJES. 2014;9(1):26. 10. Decadt B, Sussman L, Lewis MP, Secker A, Cohen L, Rogers C, et al. Randomized clinical trial of early la- paroscopy in the management of acute non-specific abdominal pain. The British journal of surgery. 1999;86(11):1383-6. 11. Banz VM, Sperisen O, de Moya M, Zimmermann H, Can- dinas D, Mougiakakou SG, et al. A 5-year follow up of patients discharged with non-specific abdominal pain: out of sight, out of mind? Internal medicine journal. 2012;42(4):395-401. 12. Lin WC, Lin CH. Multidetector computed tomography in the evaluation of pediatric acute abdominal pain in the emergency department. BioMedicine. 2016;6(2):10. 13. Coskun A, Yavasoglu I, Sargin G, Ok IM, Bircan M, Avcil M, et al. The role of mean platelet volume in patients with non-specific abdominal pain in an emergency depart- ment. Przeglad gastroenterologiczny. 2015;10(3):156-9. 14. Pappas A, Toutouni H, Gourgiotis S, Seretis C, Kouk- outsis I, Chrysikos I, et al. Comparative approach to non-traumatic acute abdominal pain between elderly and non-elderly in the emergency department: a study in rural Greece. Journal of clinical medicine research. 2013;5(4):300-4. 15. Espinoza R, Balbontin P, Feuerhake S, Pinera C. [Acute abdomen in the elderly]. Revista medica de Chile. 2004;132(12):1505-12. 16. Esses D, Birnbaum A, Bijur P, Shah S, Gleyzer A, Gallagher EJ. Ability of CT to alter decision making in elderly pa- tients with acute abdominal pain. The American journal of emergency medicine. 2004;22(4):270-2. 17. Marco CA, Schoenfeld CN, Keyl PM, Menkes ED, Doehring MC. Abdominal pain in geriatric emer- gency patients: variables associated with adverse out- comes. Academic emergency medicine : official jour- nal of the Society for Academic Emergency Medicine. 1998;5(12):1163-8. 18. Forouzanfar MM, Hatamabadi HR, Hashemi B, Majidi A, Baratloo A, Shahrami A, et al. Outcome of nonspecific ab- dominal pain in the discharged patients from the emer- gency department. Journal of Gorgan University of Med- ical Sciences. 2014;16(2):62-8. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem Introduction Methods Results Discussion Limitation Conclusion Appendix References