Pediatric ImagingE2359. Hunting for Cat-Scratch Disease: A Multisystem Pictorial Review of Key Radiologic Findings
Amin S, McFarland W, Sharma P, Rajderkar D. University of Florida, Gainesville, FL
Address correspondence to S. Amin (email@example.com)
Background Information: Cat-scratch disease (CSD) is caused by the inoculation of Bartonella henselae, a gram-negative bacterium, either by a bite or a scratch from a cat or insect and most frequently occurs in adolescence. The condition most commonly presents with fevers, headaches, fatigue, and tender regional lymphadenopathy which subsides in several weeks with or without antibiotics. However, in 5–10% of cases, CSD may disseminate to involve multiple organ systems and mimic more serious systemic conditions both clinically and radiologically requiring a more in-depth investigation. We present a pictorial review of the common and rare imaging features of regional and multiorgan CSD using a multimodality approach and highlighting key imaging characteristics.
Educational Goals/Teaching Points: We review a typical presentation of cat-scratch disease including the initial signs and symptoms, clinical course, histopathology, diagnosis, and appropriate management in the pediatric population. We present the radiologic manifestations of typical and atypical presentations of CSD using various imaging modalities and identify mimickers and a differential for CSD in each organ involved. Viewers will learn to recognize a multitude of disease patterns for CSD, which could prompt an early diagnosis and appropriate management. We discuss potential complications for dissemination of disease to multiple organs.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques: Cat-scratch disease typically presents with fevers and tender regional lymphadenopathy, however in 5–10% of cases, it can disseminate to multiple organs making diagnosis and treatment more difficult. This is more prevalent in immunocompromised patients and can lead to increased morbidity. The diagnosis is usually made from a combination of clinical history, imaging, and serologic studies and is typically treated with antibiotics. The involved lymph nodes, most commonly axillary or epitrochlear lymph nodes, can be hyperemic, centrally necrotic, easily characterized by ultrasound, and palpable. Systemic involvement of other organs is generally better appreciated with cross-sectional imaging. We present a variety of examples of regional and multiorgan CSD manifesting as lymphadenopathy with suppuration or abscess formation in typical and atypical locations, hepatosplenomegaly, liver and spleen microabscesses and granulomas, bacillary angiomatosis, pulmonary nodules, retinopathy with retinal detachment, encephalitis, multifocal osteomyelitis, and discitis/osteomyelitis in a multimodality manner including radiograph, nuclear medicine, ultrasound, CT, and MRI.
Conclusion: The involvement of each organ system in isolation or in combination can be challenging for both the radiologist and clinician to arrive at the correct diagnosis of CSD. Instead, often a broad differential or multiple diagnoses are presented, which can delay treatment or lead to erroneous management. Therefore, recognizing key imaging characteristics in the appropriate clinical setting could raise suspicion for CSD and allow for a timely diagnosis and management.