https://orcid.org/0000-0002-6614-3480
Acute appendicitis (AA) is a frequent reason for a visit to the emergency department. It is therefore not surprising that appendectomy represents the most commonly performed emergency surgical procedure worldwide. Pain to the right lower abdomen with or without signs of systemic inflammatory response represents the most common sign of AA. However, pain to the right lower abdomen might be secondary to quite a number of pathologies. The broad spectrum of differential diagnosis for this cardinal symptom and the lack of specific markers for AA render the preoperative diagnosis of AA extremely troublesome.Citation1
Preventing the progression from uncomplicated to complicated appendicitis via a timely intervention remains the focus of management. The risk of perforation has been shown to increase following delayed or missed diagnosis of an uncomplicated appendicitis. Recently, antibiotics have been employed in the management of uncomplicated appendicitis.Citation2 Thus, the risk of progression to complicated appendicitis might be reduced by early use of antibiotics. Nonetheless, complications like perforation with intra-abdominal abscess formation, peritonitis, and abdominal sepsis represent severe complication of acute appendicitis. These complications might be associated with severe morbidity or mortality. Therefore, early diagnosis remains the key to a successful management. For this reason, the indication for emergency appendectomy is lavishly made. On the other hand, the risk of negative appendectomy defined as normal, uninflamed appendix following histopathology must always be considered. Negative appendectomy might be associated with serious postoperative complications.Citation3 Thus there is need for an accurate preoperative diagnosis in cases with suspected acute appendicitis.
The manuscript (UIVS-2017–0420.R2) retrospectively investigated predictive factors for complicated appendicitis.Citation4 The authors investigated the predictive values of inflammatory parameters in peripheral blood including white blood count (WBC), c-reactive protein (CRP), and liver enzymes including bilirubin, Gamma Glutamyl Transferase (GGT), Alkaline Phosphatase (ALP), and Alanine Aminotransferase (ALT) as well as findings from abdominal imaging using ultrasound (US) or/and computed tomography (Ct) in the diagnosis of AA. The decision to perform emergency appendectomy was made after considering patient´s history, findings from physical examination, blood chemistry, and imaging in accordance with common practice.Citation5
This retrospective study included 208 patients, 110 males and 98 females, with a mean age of 29 yrs. managed with AA within a three-year period. Histopathology confirmed acute appendicitis in 88.5% of cases putting the incidence of negative appendectomy in this series at 11.5%. This rate is similar to existing data.Citation6 As expected, the rate of negative appendectomy in female patients was twice that of male patients. This finding is associated with a broader spectrum of pathologies presenting with right lower pain in young females of reproductive age.
The main drawback of this work is the retrospective study design. This is particularly of importance taking into account that inflammatory markers (WBC and CRP) were not available in about 10% of cases. For example, WBC and CRP were missing in 17% and 21% of cases with negative appendectomy compared to 7% and 8% in the group with positive appendectomy, respectively. Looking at the reported positive predictive value for both markers (90.5% for WBC and 92.7% for CRP) the magnitude of this limitation becomes even clearer. This limitation however should not stand alone. As the authors reported, findings from physical examination were considered in the decision-making regarding the need for appendectomy. The clinical judgment of an experienced clinician might warrant exploration even in some cases without pathologic inflammatory markers.
Another important issue highlighted in this paper is the use of imaging in patients with suspected appendicitis. Preoperative imaging was ordered in over half of the study population. Abdominal ultrasound was found to be very sensitive (100%) with a negative predictive value of 100%. Although findings from abdominal ultrasound sonography might differ among sonographers, this is a very encouraging finding for a readily available and cheap imaging tool. While the sensitivity of computed tomography (CT) in diagnosing AA in this series was equally high (97.7%), the negative predictive value was unacceptably low (50%). These findings justify the use of abdominal ultrasound as the primary imaging modality while questioning the need of CT in patients presenting with suspected appendicitis. Besides, pelvic radiation in a population of reproductive age must be considered.Citation7 Nevertheless, both imaging modalities might be used sequentially in unclear situation as reported in this study.
Another critical point discussed in this paper is the importance of routine histopathology following appendectomy, even in cases with macroscopic “normal” appearing vermiform appendix. The underlying pathology might not always be evident during surgery. The authors found among other pathologies neoplasia (neuroendocrine tumor) in 4.2% and reactive lymphoid hyperplasia in 12.5% of cases in this study. These pathologies can only be diagnosed following histopathology and might warrant further intervention. This is a meaningful finding in light of the controversial discussion with regard to the need of routine histopathology following appendectomy.Citation8
Despite the small size of the population and the retrospective study design, this paper deals with a very common disease, which unfortunately is not always easy to diagnose. The importance of this issue is reflected by the intensity of research on diagnostic markers for AA.Citation9,Citation10
In accordance with the principal precept “primum nil nocere” (first, do no harm), clinicians and surgeons must be aware of the potential complication that might result following any surgical procedure. Such complications are even more disastrous in cases without a clear indication for surgery as might be the case following negative appendectomy. Thus, there is a need for more investigation to improve the preoperative diagnostic accuracy of AA with the hope of reducing the rate of negative appendectomy.
DECLARATION OF INTEREST
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.
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