What is Recurrent Respiratory Papillomatosis (RRP)?
Respiratory papillomatosis is the most common non-cancerous tumor of the upper airway in children. It is caused by the human papilloma virus. RRP is a small “wart-like” growth. It can be found in the nose, pharynx (throat), larynx (voice box), trachea (windpipe), esophagus (swallowing tube) and the lungs.
RRP in the voice box is the most common.
Signs and SymptomsThe most common symptom noted with laryngeal (voice box) RRP is a change in voice quality such as hoarseness or loss of voice. The changes are usually gradual and do not get better except when RRP is removed. Children may have recurrent croup symptoms such as a barky or “seal-like” cough or stridor (noisy breathing). Due to the slow growth of RRP within the airway, children rarely have sudden breathing problems but, over a period of time, may develop severe airway blockage.
Diagnosis of RRP
While the child is awake, a small flexible telescope is passed through the nose and throat to look for RRP in the upper airway, to the level of the vocal cords. If RRP is in the upper airway, it can be seen with this scope.
A microscopic laryngoscopy and bronchoscopy (MLB) may need to be done to look at the airway below the level of the vocal cords in addition to the voice box. This is done in the operating room with the child under a general anesthetic.
Treatment for RRP
The goal of treatment for RRP is keeping the airway safe. This is done by repeated removal of RRP. In a small number of children with very severe disease, a tracheotomy may be needed to maintain a safe airway. This is quite rare, however. Surgical treatment will not cure RRP but is the most common treatment for RRP until the child’s immune system fights off the virus (HPV) and the RRP decreases.
Many surgical treatments exist for removing RRP. Lasers are able to destroy the RRP tissue. Mechanical shavers (microdebriders) allow RRP to be suctioned and cut free from the nearby tissue with great accuracy.
Other types of treatment have also been explored in the treatment of RRP. None of these have consistent results. Cidofovir is an antiviral medication that acts against DNA viruses. The use of injections of this medication into the RRP is being studied.
The control of esophageal reflux disease with medications has also been helpful in the treatment and slowing of virus activity in some patients.
The history of RRP is naturally solved in time in most children. When this will occur is unknown. Surgery is needed to keep a safe airway until the RRP lessens. Though treatments used should not create damage to nearby airway structures, any surgery can have problems. Movement of RRP into the trachea and lungs can occur. This makes treatment of the disease much more difficult, and life-threatening problems may develop.
RRP is thought to be caused by acquisition of human papillomavirus (HPV) during passage through the birth canal of an infected mother. HPV6 and HPV11 are most commonly involved.
There are three different vaccines that have been clinically developed, varying in the number of HPV types they contain and target. In the United States, the 9-valent vaccine is available. The CDC recommends routine vaccination at 11 to 12 years of age for all children, but they may start as early as 9 years of age.