Case Presentation: A 22yo woman with no PMH presented with 2 days of right axillary swelling. She endorsed a 5lb unintentional weight loss and a vague 2 year history of night sweats, but no fevers. She denied paraffin wax use. She works on a farm with rabbits, goats, and cats and reported tick exposures.Her exam revealed a 1.5in tender mass in the right axilla with overlying redness. Differential included lymphadenitis, reactive lymphadenopathy, a cystic lesion, abscess, atypical mycobacterial infection, and malignancy. A bedside ultrasound (US) revealed a well-circumscribed, heterogeneously hypoechoic mass in the superficial soft tissues with surrounding hyperemia. While not consistent with an abscess, it raised concerns for an inflamed or malignant lymph node, so bedside drainage was not attempted. Formal ultrasound confirmed the findings. She was started on empiric clindamycin for 14 days.Labs included CBC with WBC 11.9 10*9/L and absolute neutrophils 9.1 10*9/L, normal LDH, and negative HIV, bartonella, and quant gold testing. Despite antibiotics, she had persistent pain and swelling and subsequently had a core biopsy 12 days into her course. Spontaneous drainage of serous fluid resulted in reduction of the mass size on repeat exam. Tularemia serologies returned with “borderline IgM, negative IgG,” prompting treatment with a 10 day course of ciprofloxacin. Surgical pathology showed mixed chronic and granulomatous inflammation, negative Fite, Gram, and Warthin-Starry stains for organisms and no evidence of malignancy. Repeat tularemia serologies again showed borderline IgM and negative IgG, suggesting the final diagnosis of glandular tularemia.
Discussion: Tularemia is an infection caused by the bacteria, Francisella tularensis. Rodents, rabbits, and hares are common reservoirs and humans acquire the infection through contact with an infected animal, via ingestion, or vector bite (particularly ticks) (1). The ulceroglandular form is the most common presentation in the USA, with glandular, oculoglandular, oropharyngeal, pneumonic, and typhoidal forms as well. Diagnosis is initially clinical, as antibodies do not develop until at least 2 weeks after symptom onset. A fourfold or greater increase in titer from the initial to the convalescent serologies confirms the diagnosis. Glandular tularemia can present as lymphadenitis, an abscess, or an undifferentiated fluid collection, most commonly in the cervical region (1). These can be hard to differentiate by physical exam, making the decision about whether or not to incise and drain a difficult one. Bedside US provides additional information that can prevent unnecessary procedural attempts at the bedside, and there is increasing evidence that US increases diagnostic accuracy in skin and soft tissue infections and often changes management (2,3). There are no clear recommendations as to whether fine needle aspiration or excision of the mass is superior, as a portion of those FNAs require full excision (4).
Conclusions: Tularemia should be considered in the differential of lymphadenopathy in patients with the appropriate clinic presentation and risk factors, and empiric treatment should be initiated due to the delayed presence of antibodies. Bedside ultrasound with suspected tularemia-associated lesions may prevent unnecessary procedures and minimize patient risk. More studies are needed to provide guidance on when drainage is needed in patients with glandular/ulceroglandular tularemia.