Evaluation of Patients with Possible Acute Appendicitis

Reynaldo O. Joson, MD

1990

UPCM-PGH Consultant Forum

In the evaluation of patients with possible acute appendicitis, two approaches are being practiced. One approach is with the use of laboratory examinations in consonance with history and physical examination. The other approach is without the use of laboratory examinations, just based on active observation.

This paper addresses two questions. The first question is how Filipino physicians in general evaluate patients with possible acute appendicitis. To answer this question, a survey was done in one private Metro Manila hospital, the Manila Doctors Hospital, and in one government hospital, the Philippine General Hospital. The survey showed 78-100% of patients with possible acute appendicitis had lab exams, 78% in the private hospital and 100% in PGH. The two most common lab exams were CBC and urinalysis, which were practically done on a routine basis.

The second question addressed by this paper is what could be a cost-effective way of evaluating patients with possible acute appendicitis. In other words, is the evaluation without lab exams as accurate as that with lab exams? To answer this question, an analysis was done on the author’s method of evaluation and those of physicians in the private hospital.

In the private hospital, of the 179 operated patients with lab exams, 92% turned out to have acute appendicitis and 8% non-appendiceal diseases. Of the 49 operated patients without lab exams, 94% had acute appendicitis and 6% had non-appendiceal diseases. Comparing the accuracy rates of the two diagnostic approaches, with or without lab exams, they are practically the same.

From 1982 up to the present, I have been using a uniform method of evaluation for patients with possible acute appendicitis. I don’t order for CBC and urinalysis. I just rely on close active observation which consists mainly of serial palpation of the abdomen, especially the right lower quadrant. I palpate the abdomen to look for signs of peritoneal irritation which consist of definite, persistent, increasing direct tenderness and muscle guarding. If a RLQ peritoneal irritation is present, then an operation is carried out as soon as possible. The active observation starts from the time of consultation up to the time that I am confident that RLQ peritoneal irritation is present or not present. This active observation can range from several minutes to 2 to 3 days after initial examination. For those who were not operated on, a final clearance is, however, only made after a total of two-week observation.

Before I discuss the rationale of this approach, I would like to present first my personal series of 504 patients. 202 were females. 242 were males. The age range was from 7 to 71 years old. 245 were not operated and subsequently cleared of surgical abdomen. 259 were operated. Of these patients, 85% turned out to have acute appendicitis and 5% had nonappendiceal diseases. 186 were operated on the first day; 71 were on the second day; and 2 on the third day of observation. There was no mortality. The overall wound infection rate was 6%.

Thus, based on my series and on the series in the Manila Doctors Hospital, I say that the accuracy rate of evaluation without lab exams, just based on active observation, is comparable to that using lab exams. Because of this finding, I say that evaluation without lab exams is more cost-effective. I say further that it is accurate, safe, and it avoids the pain, inconvenience, and expenses of lab exams.

Now, for the rationale of this active observational approach.

First, there is no way of establishing a definite diagnosis of acute appendicitis preoperatively. Clinical diagnosis of acute appendicitis is always only a suspect.

The most common lab exams used are CBC and urinalysis. I don’t know the rationale for their use. An abnormal WBC is not specific for acute appendicitis. A normal WBC count does not rule out acute appendicitis.

A normal urinalysis is not indicative of appendicitis. An abnormal urinalysis does not rule out acute appendicitis.

Establishing a disease other than appendicitis through lab exams does not rule out acute appendicitis because acute appendicitis can coexist with urinary tract infection and other diseases, for that matter.

For those of you who have experienced with patients who were operated with normal CBC and normal or abnormal urinalysis, who do you think was the deciding factor for the operation? It is the abdominal findings!

The type of suspicion that will lead to a high accuracy in the clinical diagnosis of acute appendicitis is one that is based on the presence of RLQ peritoneal irritation and the thinking that acute appendicitis is the most common cause of RLQ peritoneal irritation.

Another rationale for the active observational approach is that acute appendicitis has different pathological stages. When a patient presents in the early stage of acute appendicitis, the diagnosis is difficult because signs of peritoneal irritation are minimal or absent. Acute appendicitis is easy to diagnose when there are already definite signs of peritoneal irritation. This is the rationale for the active observational approach, to look for definite signs of peritoneal irritation.

The main fear for the active observational approach is that there could be an increased incidence of ruptured appendicitis associated with increased morbidity and mortality. The studies of Thomson and Magnant and myself have shown that this fear is unfounded. In my personal series, there was no increase in the incidence of perforation. No mortality was encountered. The wound infection rate was only 6% which falls within the usual range of 6-7% reported in the literature.

Thus, after the above presentation, I say that to rule in and to rule out acute appendicitis, lab exams are not needed. What is needed is an active observation to look for signs of peritoneal irritation.