### Description

Decision making in patients being evaluated for acute appendicitis can be aided by the use of a simple scoring system based on clinical and laboratory parameters. It is intended for use when there is uncertainty as to the diagnosis of appendicitis and the need for immediate surgery.

Parameters:

(1) gender of patient

(2) age

(3) duration of pain

(4) presence of genitourinary (GU) symptoms

(5) muscle spasm in the right lower quadrant

(6) rectal mass on right side

(7) WBC count

 Parameter Finding Points gender male +2 female -1 age 20-39 years of age -1 >= 50 years of age +3 < 20 or 40-49 0 duration 1.5 days (36 hours) +2 2 days (48 hours) +1 3 days or more -3 <= 1 day 0 GU symptoms present -3 absent 0 muscle spasm right lower quadrant involuntary +3 none -3 rectal mass right side present -3 absent 0 WBC < 10,000 per µL -3 10,000 - 13,000 0 > 13,000 per µL +2

where:

• The score for a duration of symptoms if > 3 days is uncertain.

• Scoring muscle spasm in right lower quadrant if present and not involuntary is uncertain.

score =

= SUM(points for all 7 parameters)

Interpretation:

• minimum score: -17

• maximum score: +12

• As the score increases, the probability of appendicitis increases; as the score decreases the probability of non-appendicitis cause increases.

• In the series of patients used for the paper, all patients with scores > 7 had appendicitis and all patients with scores < -7 had non-appendicitis cause, with a large area of overlap in between. About a third of patients with appendicitis had scores < 0, while a third of patients without appendicitis had scores > 0

• Using a cutoff score of -3 to separate observation from surgery, about 5% of patients with appendicitis would be observed. 62% of patients without appendicitis would have surgery while 38% would be observed.

• During observation patients without appendicitis had scores which tended to decrease with time.

Patients with appendicitis and scores < -3

(1) all women

(2) all had a short history of symptoms

(3) all had a normal WBC count

Observation patients:

(1) followed closely with hourly charting of vital signs and symptoms

(2) frequent abdominal examinations, usually every hour

(3) repeat WBC count every 2-4 hours

Indications for surgery:

(1) failure of equivocal signs and symptoms to regress in 4-6 hours

(2) progression in signs and symptoms

(3) clinical evidence of peritonitis of undetermined etiology