Zenker diverticulum (pharyngeal pouch): symptoms, diagnosis and treatment

The swallowing tube has a muscular ring at its top end, the upper oesophageal sphincter, which relaxes to let food through. Patient.info explains that a pharyngeal pouch is a pulsion diverticulum, or false diverticulum, which forms at the back wall between the pharynx and the oesophagus in an area known as Killian's triangle, a region of relative weakness between two parts of the muscle of the throat.

The Dudley Group NHS Foundation Trust describes the pouch as developing because of muscle spasm at the beginning of the gullet. Patient.info says the cause is unknown, but weakness of the muscular wall and malfunction of the upper oesophageal sphincter probably contribute. In practice, the muscle does not relax properly during swallowing, pressure builds up behind it and the lining bulges out through the weak area as a sac.

A pouch can sit unnoticed for a long time. As it enlarges, food and saliva collect in it, and this is when symptoms begin. The condition is not a cancer, but because the symptoms overlap with those of conditions that are more serious, it needs to be investigated.

Patient.info lists the usual presenting features as difficulty swallowing (dysphagia), regurgitation, aspiration, chronic cough and weight loss. There may be a lump in the neck that gurgles when pressed, and bad breath from food decaying in the pouch. The NHS trust describes difficulty swallowing, regurgitation and choking during eating as the most common symptoms, and notes that people sometimes wake at night coughing because food has pooled in the pouch.

• Food sticking in the throat or a sense that it will not go down.

• Bringing up undigested food, sometimes hours after a meal.

• Coughing or choking while eating, or coughing at night.

• Gurgling noises in the neck or a swelling in the neck.

• Bad breath and weight loss as eating becomes harder.

• Repeated chest infections, which can reflect food or saliva being breathed into the lungs.

Difficulty swallowing should never be put down to age. The sensible approach is to see a GP if swallowing has become difficult, if food is coming back up, if you are losing weight without trying or if you have a persistent cough or repeated chest infections. Patient.info lists oesophageal cancer and oesophageal strictures, webs and rings among the conditions that need to be considered when someone has difficulty swallowing, which is why a prompt assessment matters.

Call 999 if you are struggling to breathe or are choking on food that you cannot clear. The NHS trust warns that regurgitation can lead to aspiration pneumonia, so a fever, chest pain or breathlessness after episodes of choking needs prompt medical attention from your GP or NHS 111.

A GP will take a history and examine the neck and throat, and will usually refer you for specialist assessment, often by an ear, nose and throat (ENT) team or gastroenterology. Patient.info says a barium swallow is the initial investigation and may show a residual pool of contrast within the pouch. In a barium swallow you drink a liquid that shows up on X-ray, and pictures are taken as you swallow it.

Patient.info adds that endoscopy should be avoided as an initial investigation for fear of perforating the pouch, so a camera test is normally done by a specialist who already knows the pouch is there. Other tests may be used to look at swallowing function and to exclude other causes of difficulty swallowing.

Patient.info says management depends on the size of the pouch and that the emphasis has shifted from removing the pouch to dividing the cricopharyngeus muscle, the tight muscle that is considered central to the problem. The choice between techniques depends on the size of the pouch, the general health of the person and what the local team offers.

The Dudley Group service describes flexible endoscopic treatment as usually done under deep sedation, and says patients are asked to take only liquids for 24 hours and to have nothing by mouth for at least 12 hours before the procedure. Most patients go home the same day and a small number stay overnight for observation.

The same source says the most serious complication is perforation at the site of the cut, which can be clipped if noticed during the procedure. In a published series of over 500 patients, air leaked through the wall of the gullet in up to five per cent, and in that case a stay in hospital with nothing to eat or drink is needed until it has healed. It also quotes a two to three per cent risk of bleeding. It states that about 15 per cent of patients may develop recurrent symptoms, which can be treated again in the same way.

If you take blood-thinning medicines you must tell the team, because the medicine may need to be monitored or temporarily stopped. The trust says a pacemaker usually does not cause problems but the team should be informed.

Left untreated, a symptomatic pouch usually does not go away. Patient.info lists aspiration causing inhalation pneumonia as a complication, and notes that carcinoma may develop in the pouch although the true level of risk is debated. Outcomes after treatment are generally good, and the NHS trust says that the condition significantly affects quality of life, which treatment aims to restore.

While waiting for treatment, ask your GP or specialist whether a swallowing assessment by a speech and language therapist or advice from a dietitian is available, particularly if you are losing weight. The Dudley service mentions speech and language therapy colleagues supporting assessment of the pouch.

On the NHS the route runs from the GP to ENT or gastroenterology, a barium swallow and then a treatment plan. The Dudley service describes itself as a national referral centre for flexible endoscopic treatment, which shows that the procedure is concentrated in a few units and that referral between NHS trusts is possible. Some people use private specialist care for quicker assessment or a second opinion. Ask which technique is proposed, how often the team performs it and what the plan is if symptoms come back.