Anal warts and HPV: symptoms and causes. - THDLAB - CO UK

  • Anal warts and HPV: what are they?
  • Anal warts symptoms
  • Diagnosis
  • What causes anal warts?

Anal warts and HPV: what are they?

Anal warts

These are benign lesions caused by the Human papillomavirus (HPV). Otherwise known as anal condylomas, these warts start as little, brown-coloured marks around the anus or genitals that are noticeable to touch.

If ignored they usually develop in size and possibly number. Their appearance will alter becoming cauliflower-like bumps or tiny stem-like protrusions.


A sexually transmitted disease, Human Papilloma Virus can produce irregularities such as warts (condylomas) to the skin and mucous membranes.

Certain strains of HPV may cause genetic changes to some of the cells it affects.  This can lead to tumours around the anus, mouth, throat, penis and cervical carcinoma.  The cells that have been infected with HPV replicate and become resilient, taking place of the normal tissue.


Anal warts symptoms

Anal warts are lesions that can manifest in different, shapes, colours and sizes around the anus and genitals. They may also be present in and around the mouth but this tends to only happen with people who are immunosuppressed.  

To start with the lesions produced are little, raised, brown-coloured marks and are more often than not completely painless. These areas can alter in colour and structure, developing into growths akin to cauliflower heads or stem-like protrusions. These growths can be clustered or sporadic.

It is normal for the warts to then multiply and spread which may bring with it some itching. 

HPV is the cause of condylomas, however, normally there are no symptoms and it will go away naturally. Unfortunately, in the minority of people it can develop into cancer. HPV is associated with about 5% of tumours worldwide – with around one new case diagnosed every eight seconds.

It is highly advised to get yourself seen by a doctor when the symptoms first appear. 



The first method for identifying HPV is usually a Pap Test. A type of brush is used to collect cell samples from the anal canal to test for the genetic makeup of the virus. The Pap Test is not painful and there is no biopsy carried out. 

The samples are used to determine whether or not HPV is present and if so what strain.  This is important as some strains have a higher likelihood of developing into anal cancer (strain 16 and 18 are responsible for over 90% of all anal cancers). 

If there is a positive diagnosis for HPV with a Pap Test then a High-Resolution Anoscopy (HRA) examination may be performed. HRA gives the clinician the ability to fully screen the anal canal for lesions regardless of their development stage.


What causes anal warts?

Anal warts are a very infectious, sexually transmitted infection (STI) caused by the Human Papillomavirus (HPV). It is one of the most common and far reaching STIs in the world.  Transmission occurs during sexual intercourse through direct contact with the skin or mucus membranes with someone carrying the infectionMaterial items such as clothes and towels that have had contact around the genitals may also pass the infection on but this is less likely. 

The appearance of lesions (condylomas) is due to the HPV changing the cells of the skin and mucous membranes. There are strains of HPV classified as “high risk” as they increase the risk of cancer.

The immune system in a healthy individual will more often than not prevent the virus from developing lesions that could lead to tumours. However, some people are immunosuppressed or immunocompromised which can allow the virus to take hold and spread rapidly. These individuals are at a higher risk of getting HPV and anal condylomas.

Immunosuppression can be caused by many factors; chemotherapy, chronic infections, blood diseases, organ transplants, etc. but the major cause is HIV.