Cat at home? Cat scratch disease with atypical presentations and aggressive radiological findings mimicking sarcoma, a potential diagnostic pitfall

Acta Orthop. 2021 Dec;92(6):753-759. doi: 10.1080/17453674.2021.1941624. Epub 2021 Jun 24.

Abstract

Background and purpose - Cat scratch disease (CSD) is a self-limiting disease caused by Bartonella (B.) henselae. It is characterized by granulomatous infection, most frequently involving lymph nodes. However, it can present with atypical symptoms including musculoskeletal manifestations, posing a diagnostic challenge. We describe the prevalence and demographics of CSD cases referred to a sarcoma center, and describe the radiological, histological, and molecular findings.Patients and methods - Our cohort comprised 10 patients, median age 27 years (12-74) with clinical and radiological findings suspicious of sarcoma.Results - 7 cases involved the upper extremities, and 1 case each involved the axilla, groin, and knee. B. henselae was found in 6 cases tested using polymerase chain reaction and serology in 5 cases. 9 cases were soft tissue lesions and 1 lesion involved the bone. 1 patient had concomitant CSD with melanoma metastasis in enlarged axillary lymph nodes. On MRI, 5 soft tissue lesions were categorized as probably inflammatory. In 3 cases, with still detectable lymph node structure and absent or initial liquefaction, the differential diagnosis included lymph node metastasis. A sarcoma diagnosis was suggested in 4 cases. The MRI imaging features of the bone lesion were suspicious of a bone tumor or osteomyelitis.Interpretation - Atypical imaging findings cause a diagnostic challenge and the differential diagnosis includes malignant neoplasms (such as sarcoma or carcinoma metastasis) and other infections. The distinction between these possibilities is crucial for treatment and prognosis.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Anti-Bacterial Agents / therapeutic use
  • Bartonella henselae
  • Cat-Scratch Disease / diagnostic imaging*
  • Cat-Scratch Disease / drug therapy
  • Child
  • Diagnosis, Differential
  • Humans
  • Magnetic Resonance Imaging
  • Middle Aged
  • Sarcoma / diagnostic imaging
  • Soft Tissue Neoplasms / diagnostic imaging
  • Young Adult

Substances

  • Anti-Bacterial Agents