Case Study: Persistent Inflamed Sternal Nodule in a Young Woman

Case at a Glance

A 22-year-old female presented with a tender, inflamed nodule on her chest that had been present for several months and intermittently discharged purulent material, consistent with an inflamed epidermoid cyst.

Patient's Story

The patient, a 22-year-old female, presented for evaluation of a persistent skin lesion on her central chest. She reported the onset of the lesion approximately 2 to 3 months prior to the visit. She described it as a firm, subcutaneous "bump" that felt like a deep cyst. The area was erythematous and tender to palpation. The patient noted that at times, the lesion would become irritated and painful without any stimulus. She admitted to intermittently manipulating and squeezing the lesion, which resulted in the expression of purulent material, described as varying in color from white to brown or black. Occasionally, she observed a small, dark central point on the surface of the nodule.

Initial Assessment

On physical examination, a solitary, tender, erythematous nodule measuring approximately 1.5 cm in diameter was noted on the sternal area of the chest. The lesion was firm and mobile, located within the dermis and subcutaneous tissue. A central punctum was visible. There was localized warmth and erythema but no evidence of surrounding cellulitis or systemic signs of infection.

The Diagnostic Journey

The patient's history and the physical findings were highly suggestive of an inflamed epidermoid cyst. The presence of a central punctum, the subcutaneous nature, and the expression of keratinous and purulent material upon manipulation are classic features. Other differential diagnoses were considered, including a pilar cyst (less common on the chest), an inflamed lipoma (unlikely to have a punctum or discharge), or a deep folliculitis. However, the chronicity and specific characteristics strongly pointed towards an epidermoid cyst that had become repeatedly inflamed, likely due to manual manipulation and secondary bacterial colonization. Given the clear clinical picture, further diagnostic imaging or biopsy was not deemed necessary at this stage.

Final Diagnosis

Inflamed Epidermoid Cyst

Treatment Plan

The initial treatment plan focused on managing the acute inflammation and educating the patient.

1. Patient Education: The patient was strongly advised to cease all manipulation and squeezing of the lesion, as this exacerbates inflammation, increases the risk of cyst rupture under the skin, and can lead to more significant infection and scarring.
2. Conservative Management: Application of warm compresses to the area for 10-15 minutes, 3-4 times daily, was recommended to promote drainage and reduce inflammation.
3. Medical Management: Due to the signs of inflammation and purulent discharge, a short course of oral antibiotics (e.g., cephalexin) was prescribed to manage the bacterial component.
4. Surgical Consideration: The patient was informed that the definitive treatment to prevent recurrence is the complete surgical excision of the cyst, including the entire cyst wall. This procedure would be scheduled as an elective outpatient procedure once the acute inflammation resolved.

Outcome and Follow-up

The patient followed the conservative management plan. Within a week, the pain, redness, and tenderness significantly decreased. She was scheduled for a follow-up appointment in four weeks to assess the lesion and discuss elective excision. The patient was counseled that without complete removal of the cyst sac, there is a high likelihood of recurrence and future episodes of inflammation.