“Chicago Classification” Should Be Challenged in the Diagnosis of Achalasia: Heterogeneity of Achalasia

138 " Chicago Classification " Should Be Challenged in the Diagnosis of Achalasia: Heterogeneity of Achalasia Figure 1. Clinical findings of a 12-year-old female with solid dysphagia. (A) Upper endoscopy shows dilated esophagus and retained food material. (B) Lower esophageal sphincter is not opened with air inflation. (C) Esophageal dilata-tion with bird-beak narrowing of the esophagogastric junction is noted on the barium esophagogram. (D) High-resolution manometry reveals aperistalsis with normal 4 second-integrated relaxation pressure (3.9 mmHg). TO THE EDITOR: We read with interest the review article by Lee et al 1 regarding " Clinical characteristics and treatment outcomes of 3 subtypes of achalasia according to the Chicago classification in a tertiary institute in Korea. " The study showed that type II achalasia (n = 28 [50.9%]) is the most common subtype followed by type I (n = 21 [38.2%]) and type III (n = 6 [10.9%]). Interestingly, all type III patients responded to calcium channel blocker in the study. The authors suggested that type III should be a different entity from those of type I and II. We strongly agree with their opinion. We have been evaluating patients with suspected achalasia using high-resolution man-ometry (HRM) with special interest for 5 years. To our experience , the definition of achalasia according to " Chicago classification of HRM " is not perfect. We have experienced achalasia patients with normal integrated relaxation pressure (IRP). As one example, a 12-year-old female who began to experience dys-phagia for solid food approximately 2 months before presentation. Physical examination did not reveal signs of scleroderma. Upper endoscopy revealed esophageal dilatation with retained secretion and food material (Fig. 1A and 1B). A barium esophagogram showed severe disturbance in emptying into the stomach (Fig. 1C). HRM at sitting position showed aper-istalsis with normal 4 second-IRP (normal range < 15 mmHg) (Fig. 1D). Eckardt score at that time was 5. Based on this con