A 57-year-old patient presented with a large, oblong necrotic mass on the left posterior lateral region of his back.
The lesion was 35 cm x 16 cm, tender, but firm with an erythematous border. His last visit was six years prior, during which an inflamed cyst on the mid portion of his back was treated with an intralesional injection of triamcinolone. The patient never returned for follow-up and explained that he had lost his health insurance.
Physical exam revealed a well-developed, well-nourished male in no acute distress, alert to person, place and time. The patient was afebrile and had normal vital signs.
The patient ranked the lesion as 7/10 on the pain scale, and stated that he had been having trouble sleeping. He did not try any home remedies, nor did he take any medications. He denied any constitutional symptoms.
The patient reported smoking and drinking beer on the weekends. He requested to have the lesion lanced.
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On occasion, even common medical problems can present atypically. Cysts are typically considered cosmetic nuisance rather than a significant medical problem.
The lesions are generally benign, filled with keratin, fluid, pus or sebum. They are common on the skin and can appear anywhere, and present as freely mobile nodules under the surface of the skin.
But even a simple cyst can become unusually large and problematic, as is the case with this patient. After years of neglect, his cyst grew to an impressive size with secondary inflammation and necrosis.
Diagnosis & Treatment
Cysts can develop as a result of infection, clogging of sebaceous glands or hair follicles, or around foreign bodies, such as piercings. Most cysts are slow growing and non-tender. Diagnosis is by physical exam, which generally reveals a smooth surface to the touch, mobile and/or fluctuant under the skin.
Cysts usually do not cause pain unless they rupture or become infected or inflamed. Most cysts do not resolve without some kind of intervention, and some may need to be drained to relieve symptoms of pressure or to remove an abscess.
Incision and drainage is most often the treatment of choice. Occasionally, inflamed cysts can be treated with an injection of triamcinolone to reduce the size and/or inflammation. Recalcitrant or infected cysts will require surgical excision.2
In this patient, the cyst was identified as an infected, ruptured epidermal inclusion cyst. It was excised and the surgical specimen was sent to the pathology lab.
The pathology report revealed skin and subcutaneous tissues with cutaneous ulceration, necrosis and abscess formation. There was no evidence of atypia or malignancy. In addition to excision, the patient was also prescribed antibiotics and recovered completely.
Melba Ovalle, MD, is the Medical Director and Assistant Program Chair at Nova Southeastern University’s Physician Assistant Program in Orlando, Fla.
- Pathology Lab, Glenview, Il. 60090.
- Fromm LJ, Zeitouni NC. Epidermal Inclusion Cyst. 6 June 2012. Medscape. Retrieved 4/24/14 from http://emedicine.medscape.com/article/1061582-overview