6 common causes of lumps behind the ear and when to see a doctor.
Finding a lump on the area of skin behind your ear can cause anxiety. Fortunately, lumps and bumps are usually completely harmless and easily treatable.
Dr Roger Henderson looks at the possible causes for lumps behind your ear, any treatments that may be needed, and when to seek medical advice:
What causes a lump behind the ear?
There are many possible reasons why you may notice a lump behind an ear, including the following:
Skin cysts are small, fluid-filled sacs that can occur anywhere on the skin and are often caused by blocked skin glands. One of the commonest types are called sebaceous cysts which are often seen on the head, neck and back. These arise from blocked sebaceous glands that produce the oily secretions that lubricate the skin. These are harmless but can occasionally become infected when they can be red, painful and increase in size. Skin cysts are typically mobile and so can be moved from side to side.
Acne is a very common skin condition, particularly in younger people. In this condition, pores and follicles in the skin become blocked with oil and dead skin which forms a layer called a comedone. This can cause a lump on the skin which can become infected and inflamed, including behind the ear.
Lipomas are completely harmless fatty lumps that develop under the skin and which may occur anywhere on the body. If these are very small they may not be felt but if larger you can feel them as a small, soft and mobile lump that is usually painless. They range in size from pea-size to an inch or two in diameter. Compared to a skin cyst, lipomas are usually found deeper in the skin and feel much softer.
Enlarged lymph glands are one of the most common reasons for a lump developing behind the ear.
- Skin abscesses
When cells or body tissues become infected, the body’s natural defences send white cells to that area to help fight off the infection. This can lead to a build-up of fluid as well as swelling of the area. If the white cells accumulate then pus can start to develop, which is a mix of white cells, bacteria, and tissue. If this continues then an abscess may form which is painful, warm, tender to the touch and may sometimes discharge yellowish pus.
- Enlarged lymph glands
Enlarged lymph glands are one of the most common reasons for a lump developing behind the ear and is a reaction the body being exposed to potential infection from bacteria and viruses. The lymph nodes behind the ear are called the posterior auricular lymph nodes and if they swell up these are usually felt as small painless pea-sized lumps behind the ear. They should be painless and go back to a normal size within 2-3 weeks, usually being triggered by a skin or ear infection in that area (such as otitis media).
Mastoiditis is a serious ear infection occurs and does not get treated effectively, then the infection may affect the part of the skull bone behind the ear called the mastoid, causing the problem known as mastoiditis. This type of infection is more common in children than adults but is a serious problem requiring medical attention with antibiotics and sometimes assessment by an ear, nose and throat (ENT) specialist. It can cause pus-filled cysts to develop behind the affected ear which are felt as lumps.
How do I know what type of lump it is?
If the lump is soft, painless and moves around when you touch it then it is likely to be a lipoma or a simple skin cyst. If it is painful to the touch, or tender generally it may be an abscess or infected spot or cyst. If other symptoms are present such as a high temperature, headache or feeling generally unwell then an infection is likely.
When should I see a doctor?
Although the majority of lumps behind the ear are completely harmless and will settle over a few weeks with no treatment, seek medical advice if the following occurs:
- The lump remains unchanged after 2-3 weeks
- The lump is painful or discharging
- The lump appears very suddenly
- The lump increases in size or shape
- The lump does not move or feels ‘fixed’ behind the ear
- Other symptoms are present such as a temperature, feeling unwell or weight loss.
Your doctor will usually diagnose the lump by a simple examination and prescribe treatment such as antibiotics if necessary. Occasionally a lump may require further investigation and a sample may be taken from it (a biopsy) or imaging tests such as X-rays and MRI scans may be undertaken.