Case Study: Recurrent Unilateral Lower Limb Nodules in a Young Healthcare Worker

Case at a Glance

A 22-year-old female healthcare worker presented with a three-week history of recurrent, painful, erythematous, and indurated lesions appearing sequentially on her right leg. The presentation was highly suggestive of recurrent cellulitis.

Patient's Story

The patient, a 22-year-old female working in a nursing home, presented with a chief complaint of recurring skin lesions on her right leg over the past three weeks. She reported that a new lesion had appeared approximately once a week. The lesions began as small, pimple-like bumps that were not itchy but were tender to the touch. They would progress over a day or two to become red, swollen, hard, and warm. The first two episodes resolved spontaneously within about two days. The current, third lesion, located on her upper thigh, concerned her as it seemed different. While the central redness had decreased, the overall area of erythema and hardness had expanded. The pain prompted her to apply a foam dressing, which provided some symptomatic relief. She noted a faint, dark ring around the lesion, which she attributed to her own manipulation.

Initial Assessment

On physical examination, the patient was afebrile and in no acute distress. Her BMI was calculated to be 31.4 kg/m², which is classified as obesity. Examination of the right upper thigh revealed a tender, indurated, erythematous plaque approximately 5-6 cm in diameter, with poorly defined borders and noticeable warmth on palpation. A faint perilesional ecchymosis was present. There was no fluctuance, drainage, or visible entry point such as a cut or insect bite. No signs of lymphangitis were observed, and inguinal lymph nodes were not palpable. Examination of the sites of the previous two lesions on the same leg showed no residual changes.

The Diagnostic Journey

The patient's clinical presentation—localized erythema, warmth, swelling, and tenderness—was classic for cellulitis, a bacterial infection of the deeper dermis and subcutaneous tissue. The recurrent and unilateral nature of the episodes, combined with her occupation in a healthcare setting, raised suspicion for a potential source of inoculation or colonization with more resistant organisms like MRSA. The differential diagnosis included simple furunculosis (a boil), an inflamed epidermoid cyst, or an insect bite reaction. However, the expanding nature of the erythema and the systemic sign of warmth were more consistent with cellulitis. Given the recurrence, underlying predisposing factors such as minor, unnoticed skin trauma, or folliculitis acting as a portal of entry were considered.

Final Diagnosis

Recurrent Cellulitis of the Right Leg.

Treatment Plan

Based on the clinical diagnosis of cellulitis, a conservative outpatient management plan was initiated. A course of oral antibiotics with coverage for common skin flora (Staphylococcus and Streptococcus) was prescribed. The initial recommendation was for a first-generation cephalosporin. Adjunctive therapies were also recommended, including warm compresses to the affected area to promote circulation and aid resolution, as well as elevation of the limb to decrease swelling. The patient was instructed to avoid manipulating the lesion and was educated on signs of worsening infection that would necessitate immediate re-evaluation, such as fever, rapidly spreading redness, or increased pain.

Outcome and Follow-up

The patient was scheduled for a follow-up in 48-72 hours to assess her response to oral antibiotics. If her condition failed to improve or worsened, the treatment plan would be escalated to include consideration for antibiotics with MRSA coverage or, in a severe case, hospital admission for intravenous (IV) antibiotic therapy. The patient was also counseled on the importance of skin care and hygiene to reduce the risk of future episodes.