Glandular tularemia in a Native American child

Ear, Nose & Throat Journal, Nov, 2003 by Patrick J. Collison, Brent Adams

Abstract

This case report details the clinical manifestation and course of glandular tularemia, an uncommon but significant cause of cervical lymphadenopathy in children. We discuss the unique attributes of this disease along with appropriate steps that lead to early identification of the organism and effective treatment. The potential use of the organism as a bioterrorism agent is another interesting aspect of this entity.

Introduction

Children with infectious cervical lymphadenopathy are frequently seen by pediatricians and family practitioners. The etiologic agents in most cases are commonplace, and the diagnosis and treatment are straightforward. But some rare cases require a more thorough approach to identification of the pathogen and the attention of a surgical specialist for biopsy or incision and drainage of an abscess.

One uncommon but significant cause of cervical lymphadenopathy in children is glandular tularemia. The causative pathogen--Francisella tularensis--is of interest for several reasons. First, making a definitive microbiologic identification of F tularensis is challenging because of its fastidious growth characteristics and potential hazard to laboratory workers. Moreover, the risk of morbidity and mortality in patients with glandular tularemia is best minimized by specific antimicrobial therapy that is not usually considered for the more common causes of infectious lymphadenopathy. Finally, F tularensis is considered a potential bioterrorism agent because of its virulence, transmissibility as an aerosolized agent, hardiness in nature, and ability to cause illness with only a small amount of inoculum.

In this article, we describe a case of glandular tularemia in a child, and we review the physical, laboratory, and radiologic findings of this disease as well as the response to medical and surgical therapy.

Case report

A 3-year-old Native American boy was brought to a family physician with symptoms of an upper respiratory tract infection and increasing fever. His medical history was unremarkable, and his immunizations were up to date. He was initially treated with amoxicillin, acetaminophen, and ibuprofen. However, 2 days later, his fever had risen to 105.2[degrees]F, and he had developed a 3 x 4-cm left upper cervical swelling that featured a red streak. Laboratory studies revealed that his white blood cell (WBC) count was 4,640/[mm.sup.3], his segmented neutrophil level was 43%, his band neutrophil level was 18%, his lymphocyte level was 31%, and his monocyte level was 8%.

The boy was admitted to a community hospital and started on intravenous cefotaxime at 500 mg every 8 hours, but he remained febrile and irritable. He was transferred to the Department of Pediatrics at Avera Sacred Heart Hospital in Yankton, S. Dak. Examination there revealed that the 3 x 4-cm tender mass was located deep to the superior sternoeleidomastoid muscle and that the patient's left tympanic membrane was erythematous. His temperature was 102[degrees]F, his WBC count was 4,700/ [mm.sup.3], his band neutrophil level was 17%, and his C-reactive protein level was 10.8 mg/dl (normal: 0.5 to 1.0); a screening test for streptococcal infection was negative. Chest x-ray detected some cardiac enlargement and distention of the pulmonary vessels. Computed tomography (CT), with and without contrast, identified the 3-cm rim-enhancing mass deep to the sternocleidomastoid (figure 1).

[FIGURE 1 OMITTED]

An otolaryngologist was consulted, and the next day the patient was taken to the operating room. During surgery, a multilocular, thick-walled, abscessed lymph node was drained, and necrotic tissue was removed for histologic examination. Stained cultures were obtained to look for aerobic and anaerobic organisms and tuberculosis. Postoperatively, the patient was administered IV clindamycin at 150 mg every 6 hours and IV cefotaxime at 500 mg every 8 hours.

Initially, the patient showed slight improvement. However, by the time his Penrose drain was removed 48 hours after surgery, his mass persisted, his temperature was 102[degrees]F, his WBC count was 21,000/[mm.sup.3], and runs of bradycardia (48 to 50/min) were noted. In the initial culture and sensitivity report, the pathologist suggested a Hemophilus species as a possible pathogen, and the histologic analysis found widespread necrotizing acute inflammation (figure 2).

[FIGURE 2 OMITTED]

The pathologist entertained the possibility of cat-scratch disease, and recommended that additional tests be performed to search for a bacteriologic source. One week after surgery, a reference laboratory in Salt Lake City identified F tularensis in the abscess fluid, which established the diagnosis of glandular tularemia. The patient was treated with IV gentamicin at 60 mg every 12 hours for 2 weeks, and his symptoms resolved completely. During the patient's recovery, his mother noted that the boy often played with several feral cats that frequented the area around their home. These cats were most likely the vector for the infection.