Bilateral lymphadenopathy in a young woman.

A 20-year-old woman presented to the emergency department with bilateral tender neck masses that had been increasing in size for 2 months. Associated symptoms included weakness, headaches, neck pain, dysphagia, and left-sided earache. In the previous week, she had developed a cough productive of white sputum, chest pain, and shortness of breath. She denied fevers, night sweats, and myalgias but did have occasional chills. She had developed a rash on her arms and lower extremities 3 weeks prior, which was now resolving, and tingling in her feet. She had minimal weight loss secondary to decreased appetite over the previous few months. Several weeks prior to admission, she had been diagnosed with mumps. She was also given a 5-day course of azithromycin that did not alleviate her symptoms. She reported that 6 months earlier, her boyfriend and another good friend had been treated for tuberculosis, but she had not been tested. She received standard vaccinations as a child. She denied alcohol, tobacco, and intravenous drug use. Her family history was significant for lung cancer and thyroid disease. She had not recently traveled outside of the United States, and she had been exposed to dogs but not to cats. Physical examination revealed a healthy appearing young woman with significant bilateral cervical lymphadenopathy that was tender to palpation. The skin over the masses was not discolored and did not have draining sinus tracts. Her oropharynx was clear and nonerythematous. Her lungs were clear. She had a resolving rash on her extremities. The remainder of her examination was normal. A posteroanterior and lateral chest radiograph revealed no abnormalities in her lungs. A computed tomography (CT) scan of the neck demonstrated large, bilateral, necrotic lymph nodes extending from the high to low internal jugular lymph node chains (Figure). Figure Contrast-enhanced CT images of the neck. (a) Coronal image demonstrating multiple large necrotic lymph nodes. (b) Coronal image at a more posterior level, showing involvement of nodes in levels 2 to 4. Nodes are centrally hypodense, representing necrosis, ... What are the differential diagnostic considerations? What is the most likely diagnosis? What tests can confirm the diagnosis? DIAGNOSIS: Infectious cervical lymphadenitis, or scrofula, likely caused by M. tuberculosis. The most likely etiology, considering exposures, age, and symptoms, was cervical tuberculous lymphadenitis, or scrofula. However, the broad differential diagnosis of enhancing cervical lymphadenopathy in an adult includes metastatic squamous cell carcinoma, metastatic papillary thyroid carcinoma, lymphoma, tuberculous and nontuberculous mycobacterial lymphadenitis, cat-scratch disease, Kaposi's sarcoma, AIDS-related lymphadenopathy, Kimura's disease, Castleman's disease, and Kikuchi's disease. Fungal and viral infections, such as Epstein-Barr virus, cytomegalovirus, and rubella, also may present with bilateral diffuse lymphadenopathy. Imaging of the chest, abdomen, and pelvis revealed no systemic lymphadenopathy or other abnormalities. A tuberculin skin test (purified protein derivative [PPD]) was positive. Acid-fast bacilli (AFB) and fungal blood cultures were negative. An HIV antibody test, monospot, and cytomegalovirus polymerase chain reaction (PCR) test were negative. Her angiotensin-con-verting enzyme level was within normal limits, an antinuclear antibody screen was minimally positive at 1:80, her sedimentation rate was elevated at 40 mm/h (reference range, 0–20), and her lactic acid dehydrogenase level was elevated at 248 U/L (reference range, 135–214). Lymph node sampling by fine-needle aspiration showed caseating granulomatous inflammation, but AFB and fungal smears and Mycobacterium tuberculosis (MTB) PCR results were negative. This sample eventually grew pansensitive MTB, also identifiable by MTB probe. A QuantiFERON-TB Gold test was sent and returned with a positive result.