Skin Lump
Is this your child's symptom?
- A skin lump or bump covered by normal skin
- Skin swelling just in one spot (localized) is also included
Causes of Skin Lumps
- Insect Bites. The most common cause of an itchy bump is a mosquito bite. Other insects can also cause little bumps.
- Stings. A bee sting can cause a painful bump. The swelling can become quite large.
- Lymph Nodes. Most common cause of a lump or mass felt under the skin. Commonly found in the neck or groin. Nodes have a boundary or edge and are movable. This is not the case for the swelling seen with insect bites. Lymph nodes become larger with infections.
- Scalp Hematoma. The most common cause of a lump on the head is a scalp hematoma (goose egg). In a child under 2 years of age the injury may not have been seen.
- Injuries. New lumps anywhere can be caused by an injury that wasn't observed. A bruise is often present with the swelling.
- Callus. Broken bones heal with new bone formation. The medical term is callus. The callus feels like a bony knot that is larger than the bone itself. A callus is most commonly felt after a collarbone fracture.
- Boils. A boil is a skin abscess. It causes a very painful red lump.
Lumps that are a Normal Part of the Body
- Breast Bud. A small disc-shaped lump felt under the nipple. It indicates the onset of puberty in 7-12 year old girls.
- External Occipital Protuberance. The bony lump felt at the base of the skull in back.
- Mastoid Process. The bony lump felt behind each lower ear.
- Xiphoid Process. A small hard lump felt at the lower end of the sternum (breastbone).
Common Objects Used to Guess the Size
- Pea or pencil eraser: ¼ inch or 6 mm
- Dime: ¾ inch or 1.8 cm
- Quarter: 1 inch or 2.5 cm
- Golf ball: 1 ½ inches or 3.8 cm
- Tennis Ball: 2 ½ inches or 6.4 cm
When to Call for Skin Lump
Call Doctor or Seek Care Now
- Redness spreading from the lump with fever
- Groin swelling and painful
- Age less than 12 months and on scalp. Exception: normal bump in back at base of skull.
- Your child looks or acts very sick
- You think your child needs to be seen, and the problem is urgent
Contact Doctor Within 24 Hours
- Redness spreading from the lump without fever
- Boil suspected (painful, non-itchy, red lump)
- Age 12 months or older and on scalp. Exception: normal bump in back at base of skull.
- Can't move nearest joint normally (bend and straighten completely)
- Swelling is painful and cause not known
- You think your child needs to be seen, but the problem is not urgent
Contact Doctor During Office Hours
- Large lump more than 1 inch (2.5 cm) and cause not known
- Small lump lasts more than 7 days and cause not known
- You have other questions or concerns
Self Care at Home
- Small lump present 7 days or less and cause not known. Reason: probably due to insect bite not observed.
- Breast bud - normal lump under the nipple
- External occipital protuberance - normal lump on back of head
- Mastoid process - normal lump behind each lower ear
- Xiphoid process - normal lump at bottom of breastbone
Seattle Children's Urgent Care Locations
If your child’s illness or injury is life-threatening, call 911.
Care Advice
Treatment for a Small Lump or Swelling
- What You Should Know:
- Most new swellings are due to insect bites. Mosquito bites account for 90% of them. Your child may not even know that he got bit.
- Suspect an insect bite if there are bites on other parts of the body.
- While most insect bites cause a small red bump, some are larger (like a hive).
- This does not mean your child has an allergy or the bite is infected.
- Here is some care advice that should help.
- Cold Pack for Swelling:
- Apply a cold pack or cold wet washcloth for 20 minutes.
- Steroid Cream for Itching:
- If the swelling is itchy, use 1% hydrocortisone cream (such as Cortaid). No prescription is needed.
- Do this 3 times per day.
- Allergy Medicine for Itching:
- If itching becomes severe, give a dose of Benadryl.
- No prescription is needed. Age limit: 1 and older.
- What to Expect:
- Most insect bites itch or hurt for 1 or 2 days.
- The swelling usually peaks in 2 days, but may last a week.
- If the swelling becomes larger or doesn't go away, it needs to be examined.
- Call Your Doctor If:
- Swelling becomes very painful
- Fever occurs
- Swelling becomes large (over 1 inch or 2.5 cm)
- Swelling lasts over 7 days
- You think your child needs to be seen
- Your child becomes worse
Lumps that are a Normal Part of the Body
- Breast Buds - Normal Lump Under the Nipple:
- Breast buds are normal, small disc-shaped rubbery lumps felt under the nipple.
- Age. They normally occur in 8-12 year old girls and are the first sign of puberty. Sometimes, they are even normal in 7 year olds.
- One Side. They sometimes start just on one side. Don't worry about that. Within 2 or 3 months, a breast bud will also appear on the other side.
- Importance. The entire breast develops entirely from the breast bud, taking 2 or 3 years to completion.
- Symptoms. Breast buds normally can be somewhat tender.
- Caution: Never squeeze or massage breast buds. Reason: Can cause a serious infection.
- Risks. None. Breast buds have no risk of turning into cancer.
- Follow-up. You can have your child's doctor check the breast bud during the next regular office visit.
- External Occipital Protuberance - Normal Lump on Back of Head:
- The lump you feel at the base of the skull in back is normal. It is a bony part of the skull that sticks out and feels hard.
- If you feel carefully, you will find one on yourself or other children.
- This is not caused by any injury.
- Mastoid Process - Normal Lump Behind the Ear:
- The mastoid process is a bony lump you can feel behind the lower ear.
- Muscles that turn the neck attach to the mastoid process.
- The process is larger in men because of larger neck muscles.
- The mastoid is filled with air cells that connect to the inner ear.
- Xiphoid Process - Normal Lump at Bottom of Breastbone:
- The small hard lump at the lower end of the sternum (breastbone) is normal. It is called the xiphoid process. You can feel it.
- It is more prominent in babies and slender children. Sometimes, it's more visible when breathing in.
- If you feel carefully, you will find one on yourself or other children.
- It's made of cartilage, but turns to bone in adults.
- Call Your Doctor If:
- You have other questions or concerns
And remember, contact your doctor if your child develops any of the 'Call Your Doctor' symptoms.
Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.
Last Reviewed: 10/11/2023
Last Revised: 12/30/2022
Copyright 2000-2023. Schmitt Pediatric Guidelines LLC.