Cervical Lymphadenitis Caused by Group D Non-typhoidal Salmonella Associated with Concomitant Lymphoma
A 66-year-old woman was admitted to Samsung Medical Center on August 13, 2012, with a 10-day history of a palpable mass in the right supraclavicular area. The lesion had grown in size to 5 cm over 10 days and was complicated with pain, redness, and purulent discharge. Chest computed tomography (CT), which was performed in a other hospital on August 11, had shown a mass extending from the right cervical area to the anterior mediastinum. The patient was transferred to our hospital for further evaluation.\nThe patient had been treated for hypertension for 10 years. Two years prior to admission, she had undergone partial thyroidectomy for treating papillary thyroid carcinoma. Thyroid cancer had been localized to the right lobe of the thyroid with a size of 0.4 cm. The pathologic findings had shown no evidence of lymph node metastasis of thyroid cancer. The patient was examined periodically by a surgeon. There was no abnormal finding on a thyroid ultrasonography performed in January 2012.\nThe patient had complained of febrile sensation for 3 days. She had experienced weight loss of approximately 7 kg over the 6 previous months. On physical examination, her body weight was 54.6 kg and height was 153.4 cm. Her vital signs were as follows: blood pressure of 110/73 mmHg, body temperature of 36.6℃, heart rate of 71 beats per minute, and respiration rate of 18 breaths per minute. The size of the palpable mass was approximately 5 cm; it was located in the right supraclavicular area and complicated with redness, tenderness, and discharge.\nHer complete blood count revealed the following: white blood cells (WBC), 4,330/mm3 (neutrophils, 68.7%); hemoglobin, 12.1 g/dL; and platelets, 183,000/mm3. Chemistry profiles showed the following: aspartate transaminase (AST), 61 IU/L; alanine aminotransferase (ALT), 40 IU/L; C-reactive protein (CRP), 13.86 mg/dL; procalcitonin, 1.56 ng/mL; and lactate dehydrogenase, 661 IU/L. Thyroid function tests showed the following: triiodothyronine (T3), 42.26 ng/dL; thyroxine (T4), 8.6 ug/dL; thyroid-stimulating hormone (TSH), 0.01 uIU/mL; and free thyroxine, 1.53 ng/dL. The test result for anti-hepatitis B surface (HBs) antibody was positive. Anti-human immunodeficiency virus (HIV) antibody test were also negative. Amoxicillin/clavulanate was given empirically at a dose of 1.0 g/0.2 g, 3 times per day intravenously.\nThe chest CT showed a mass that was 66 mm in size, extending from the right supraclavicular area through the anterior mediastinum with extensive necrotic lymphadenopathy (). As the chest CT findings suggested probability of thymic carcinoma and right supraclavicular nodal metastasis, 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) was performed to assess potential cancer. PET-CT showed a visible mass in the anterior mediastinum that was seen as high 18F-2-fluoro-2-deoxy-glucose (FDG) uptake, the maximum standardized uptake value (SUVmax) of the lesion being 7.3. Further, there was high FDG uptake in the right prevascular lymph node, left mediastinal lymph node, both supraclavicular lymph nodes, and right infraclavicular lymph node; soft tissue swelling was also observed in the right supraclavicular area. These findings suggested a probability of cancer associated with infection ().\nTo confirm a diagnosis of infection and cancer, ultrasonography-guided biopsy and culture were performed. Multiple enlarged lymph nodes were observed in both supraclavicular areas. Their size was measured to range from 1.5 cm to 4 cm, and they were found to contain a variety of materials including fluid and debris (). Cultures for bacteria, mycobacteria, and fungi were performed. On hospital day 4, Gram stain results of the lymph node revealed that there were a few gram-negative bacilli. Pathologically, both of the cervical lymph nodes and the mass in the mediastinum showed infarction and granulation tissue with focal viable lymphoid cells and no bacteria observable by light microscopy (). On hospital day 7, tissue samples from the cervical lymph nodes and the mass in the anterior mediastinum were finally confirmed as diffuse large B-cell lymphoma by immunohistochemical staining.\nOn the same day, group D non-typhoidal Salmonella was isolated from cultures obtained from the lymph nodes. Growth of cultured organisms that were oxidase negative was observed on MacConkey agar, necessitating the use of an automated microbial analyzing system (Microscan system, gram negative combo panel type 53, Siemens Healthcare, Sacramento, CA, USA) to identify Salmonella to the genus level. The pathogen was confirmed to be group D non-typhoidal Salmonella using polyvalent antisera (Joongkyeom, Kyungki, Korea). Group D non-typhoidal Salmonella isolated from culture was sensitive to most antibiotics except for ampicillin/sulbactam, ticarcillin, and colistin. The results of the drug sensitivity test revealed that the minimal inhibitory concentration (MIC) for the various drugs were as follows: ampicillin/sulbactam, > 16/8 mg/L; amikacin, ≤ 8 mg/L; aztreonam, ≤ 1 mg/L; ceftazidime, ≤ 1 mg/L; colistin, > 4 mg/L; ciprofloxacin, ≤ 0.5 mg/L; cefepime, ≤ 1 mg/L; fosfomycin, ≤ 16 mg/L; gentamicin, ≤ 1 mg/L; imipenem, ≤ 1 mg/L; levofloxacin, ≤ 1 mg/L; meropenem, ≤ 1 mg/L; minocycline, ≤ 4 mg/L; piperacillin/tazobactam, ≤ 8 mg/L; trimethoprim/sulfamethoxazole, ≤ 2/38 mg/L; tigecycline, ≤ 0.5 mg/L; ticarcillin, > 64 mg/L; and tobramycin, ≤ 2 mg/L.\nOn the basis of antimicrobial susceptibility results, the antibiotic treatment was changed to ciprofloxacin. Oral ciprofloxacin (500 mg twice daily) was administered to the patient for 14 days. The mass in the right supraclavicular area improved after the administration of ciprofloxacin and the initiation of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy. The PET-CT after 2 months of treatment showed small mild hypermetabolic tumors in the right anterior mediastinum (SUVmax = 2.1) and right supraclavicular lymph node, (SUVmax = 2.4), a marked improvement compared to that in the previous scans. The patient has been receiving chemotherapy without serious complication.