What Causes Pyogenic Granulomas?

Patient Presentation
A 3-year-old female came to clinic with a draining lesion on her upper chest. The lesion had been noted about 4 weeks previously, was red and had grown in size until it was “about half a pea” and looked like a blister per her mother. It then “popped” and had draining fluid that was described as bloody but with also other “stuff” in it. It drained for a couple of days and then left a reddened area that was similar to a crater. There was no pain, redness around the area or fever. She denied any trauma. She lived on a farm with potential animal exposures. They had put a gauze bandage on it because of the non-fouling smelling discharge. The child picked at the bandage but did not seem to have pain, itching or burning of the lesion. No home photographs were available.

The past medical history was non-contributory. The family history was negative for dermatological problems or cancer. The review of systems was negative.

The pertinent physical exam showed a healthy female with normal vital signs. Her growth parameters were 10-50% and appropriate. Her examination was normal. On skin examination she had several bruises on her shins. She had a ~5 mm cafe-au-lait spot on her right lower back. On her right upper chest just below the clavicle she had a 5-6 mm, punched-out, crater-like lesion that was 2-3 mm in depth. The base had normal appearing pink granulation tissue with an area that was still ulcerated and wet. No vascular components were identified. The skin around it was slightly reddened.

The diagnosis of an unknown lesion but possible small skin abscess was made. The patient was treated with oral antibiotics because of age, her irritating the bandage/lesion and the non-specific diagnosis. She was treated for potential methicillin-resistant Staphylococcus as her father was a health care provider.

The patient’s clinical course revealed she returned to clinic 4 weeks later when the lesion reappeared. The patient had taken the entire antibiotic and the lesion healed according to the mother but then started to regrow and was very red. It had bled a small amount once when the child irritated it. The lesion was 4-5 mm, spherical and sitting on top of the surrounding skin but without a specific pedicle. It was non-tender and without erythema. The diagnosis of a pyogenic granuloma was made and the patient was referred to dermatology for confirmation and removal.

Images of similar lesions can be found here or here.

Pyogenic granuloma (PG) is a benign, vascular lesion of the skin. PGs are red, small, often pedunculated nodules that can rapidly increase in size (up to 1-2 cm). They also can often ulcerate and bleed. They frequently occur on the head and neck, with back and chest being the next most common locations but can occur in other locations. They usually are solitary and do not regress. They are seen in children (mean age 6.7 years), young adults and pregnant women (5%). Treatment is electrocautery or excision.

Learning Point
PG’s cause is not fully understood. A gene has recently been identified with PG suggesting it is a benign neoplasm and simply caused by a reactive etiology.

PG is usually an acquired lesion that occurs after skin trauma, insect bites, infection, eczema, burns, oral retinoid therapy, and underlying vascular lesions. Acquired PG can be simple to diagnose if the history and physical examination are more classic or with monitoring over time to evaluate the lesion.

Deep-seated or subcutaneous PG is not common but does occur. Congenital PG is rare and often affects the mucosa. Multiple congenital PG is even less common. It may look like infantile hemangiomas or other vascular tumors. Even on biopsy, congenital or deep-seated PG can be difficult to diagnose.

Questions for Further Discussion
1. What are common congenital vascular cutaneous lesions?
2. What are common acquired vascular lesions?
3. What cutaneous zoonoses might be considered for children exposed to domestic or non-domestic animals?
4. What are indications for referral to a dermatologist?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Skin Conditions and Benign Tumors.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Johnson EF, Davis DM, Tollefson MM, Fritchie K, Gibson LE. Vascular Tumors in Infants: Case Report and Review of Clinical, Histopathologic, and Immunohistochemical Characteristics of Infantile Hemangioma, Pyogenic Granuloma, Noninvoluting Congenital Hemangioma, Tufted Angioma, and Kaposiform Hemangioendothelioma. Am J Dermatopathol. 2018;40(4):231-239. doi:10.1097/DAD.0000000000000983

Putra J, Rymeski B, Merrow AC, Dasgupta R, Gupta A. Four cases of pediatric deep-seated/subcutaneous pyogenic granuloma: Review of literature and differential diagnosis. J Cutan Pathol. 2017;44(6):516-522. doi:10.1111/cup.12923

Schneider MH, Garcia CFV, Aleixo PB, Kiszewski AE. Congenital cutaneous pyogenic granuloma: Report of two cases and review of the literature. J Cutan Pathol. 2019;46(9):691-697. doi:10.1111/cup.13496

Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa