Although there has been a few single case series reported describing this condition [1,2,3], it was only recently that Bastian et al. [4] named this as retrograde cricopharyngeal dysfunction and presented the largest case series of 51 patients. Bastian et al. [4] also introduced for the first time the treatment of this condition using botulinum toxin A (botox) into the cricopharyngeal muscle with a long-term cure beyond the pharmaceutical period of the botox in over 90% of cases [5]. Furthermore, a single case report of a patient successfully treated with CO2 laser cricopharyngeal myotomy was reported by Bastian et al. [6] after recurrence following botox injection.
It is important that the treatment is replicated by other authors hence I reported the case series of 72 patients describing a similar condition. This is therefore the second largest case series aside from Bastian et al. [6] after searching the literature. In addition, I have reported the significance of using a larger dose of botox 100 units as standard dose. The reason for the increased dose of botox was because the initial 50 units of botox had a late response. All the patients injected with 100 units started to notice improvement that is, started burping within 48 h of injection all be it initial small burps but resume full burping by fourth week post injection. This effect lasted on average 24 months of the follow-up period.
The diagnosis of this condition is through history and clinical examination using a fiberoptic nasal endoscope and or trans nasal oesophagoscopy. Barium swallow, PH measurement and pressure manometry of the upper and lower oesophageal sphincters might be done to exclude a condition called achalasia, which is a narrowing of the gastro-oesophageal sphincter [7]. The laboratory and clinical findings in these patients might all be normal hence these patients are often told that the symptoms are psychological. For this reason, this is most likely dysfunctional condition as opposed to a physical or mechanical disorder as in achalasia or antegrade cricopharyngeal disorder due to pathologies like cricopharyngeal web or fibrosis that present with dysphagia. Some patients have already seen gastroenterologists and had oesophago-gastro-duodenoscopy (OGD), manometric and pH test and all were reported normal. Others were diagnosed as irritable bowel syndrome (IBS) or simple reflux but their symptoms did not improve after taking proton pump inhibitors and antacid or neither did they get any improvement after treatment for IBS. All patients said their social life was significantly affected and they avoid going out with friends and family due to fear of abdominal pain after eating. Two patients said they contemplated committing suicide as a result of these symptoms. Another patient had to were trousers with elastics waist as her waist line size changes throughout the day. One patient said she looks pregnant by the end of the day due to the excessive bloating of her abdomen. These findings are similar to that published by Bastian et al. [4]. There is a significant social and physical morbidity associated with this condition hence the need for clinician to recognise this whenever patients present with the above symptoms even in a normal laboratory finding.
None of the patients that had 100 units at initial injection reported recurrence. It is assumed that botox injection allows spontaneous expulsion of gas through the upper oesophageal sphincter and by the time the botox action wears off, the afferent–efferent feedback to the brain that initiate belching/burping get re-established.
Early recurrence was possibly due to failure of the afferent neural pathway to respond to the small dose of botox. However, it is unclear why even after a patent upper oesophageal sphincter following the maximum dilatation to 40 mm diameter, these patients still did not burp despite experiencing regurgitation.